JP6685873B2 - Lens unit, LED head, exposure device, image forming device, and reading device - Google Patents

Description

  The present invention relates to a lens unit, an LED head, an exposure device, an image forming device and a reading device.

  Some conventional lens units use a lens plate in which a plurality of microlenses are arranged in the longitudinal direction. There is also an LED head, an exposure device, an image forming device, and a reading device using the lens unit (for example, refer to Patent Document 1).

JP, 2013-015847, A

  However, in the conventional technology, it is required to stabilize the productivity of the lens unit.

  An object of the present invention is to stabilize the productivity of lens units.

Therefore, the present invention is a lens unit that includes a lens member in which a plurality of microlenses are arranged in the longitudinal direction, and a protective member that is arranged to be stacked with the lens member and that covers the lens member , wherein the lens unit is supported by a holding member having an opening, said protective member, in the lateral direction perpendicular to the longitudinal direction of the lens member, together with the width is wide rather than the said lens member, said retaining member It is characterized in that a sealing material is provided between the surface portion that is arranged outside the opening and that forms the opening, and the protruding portion that is wider than the lens member .

  The present invention thus configured has the effect of stabilizing the productivity of the lens unit.

Explanatory drawing of the print head in the first embodiment. Sectional drawing of the print head in a 1st Example. Sectional drawing of the print head in a 1st Example. 1 is a perspective view of a lens unit according to a first embodiment. Explanatory drawing of the laminated structure of the lens unit in a 1st Example. Exploded view of the laminated structure of the lens unit in the first embodiment. Enlarged view of the laminated structure of the lens unit in the first embodiment. Explanatory drawing of the engagement structure other than the center part of the lens unit in 1st Example. Explanatory drawing of the engagement structure of the central part of the lens unit in 1st Example. Explanatory drawing of the clamp structure of the lens unit in a 1st Example. 1 is a schematic side sectional view showing the configuration of a printer according to a first embodiment. Sectional drawing of the image sensor head in 1st Example. 1 is a perspective view showing a configuration of an image scanner according to a first embodiment. Explanatory drawing of a print head in the second embodiment The perspective view of the lens unit in a 2nd Example. Explanatory drawing of a print head in a third embodiment Sectional drawing of the print head in a 3rd Example. Perspective view of a lens unit in a third embodiment. Explanatory drawing of the laminated structure of the lens unit in a 3rd Example. Enlarged view of the laminated structure of the lens unit in the third embodiment. Enlarged view of the laminated structure of the lens unit in the third embodiment. Enlarged view of the laminated structure of the lens unit in the third embodiment. Enlarged view of the laminated structure of the lens unit in the third embodiment. Enlarged view of the clamp structure of the lens unit in the third embodiment. Explanatory drawing of the concave portion of the lens cover plate in the third embodiment. Sectional drawing of the recessed part of the lens cover plate in a 3rd Example. Sectional drawing of the recessed part of the lens cover plate in a 3rd Example. Explanatory drawing of the clamp member in a 3rd Example. Explanatory drawing of the operation | movement which fits the clamp member in a 3rd Example in a lens unit. Sectional drawing of the lens unit and clamp member in a 3rd Example. Explanatory drawing after fitting the clamp member in a 3rd Example to a lens unit. Sectional drawing of the lens unit and clamp member in a 3rd Example.

  Embodiments of a lens unit, an LED head, an exposure device, an image forming device, and a reading device according to the present invention will be described below with reference to the drawings.

  FIG. 1 is an explanatory view of a print head according to the first embodiment, and FIGS. 2 and 3 are sectional views of the print head according to the first embodiment. 1A is a perspective view of the print head, and FIG. 1B is a plan view of the print head. 2 is a sectional view taken along the line XX in FIG. 1A, and FIG. 3 is a sectional view taken along the line YY in FIG.

  The print head of this embodiment will be described with reference to FIGS.

  As shown in FIG. 1, a print head 101 as an exposure device and an LED (Light Emitting Diode) head includes a lens unit 102 held by a lens holder 109.

  As shown in FIGS. 2 and 3, the lens unit 102 includes a lens cover plate 103 and a first lens array plate in order from the side opposite to the semiconductor light emitting element 107 in the optical axis 107a direction of the semiconductor light emitting element 107 (the upper side in the drawings). The members 104a, the partition light-shielding plate 105, the second lens array plate 104b, and the incident light-shielding plate 106 are laminated and configured.

  The lens cover plate 103 as a protection member is arranged to be laminated on the first lens array plate 104a, covers the first lens array plate 104a, and protects the lens unit 102. The lens cover plate 103 is formed wider than the first lens array plate 104a in the lateral direction orthogonal to the longitudinal direction of the first lens array plate 104a.

  The first lens array plate 104a and the second lens array plate 104b as lens members are plate-shaped in which a plurality of microlenses as lenses are arranged in rows in the longitudinal direction. The first lens array plate 104a and the second lens array plate 104b are arranged such that the optical axes of the respective microlenses are aligned with each other, and the image of the semiconductor light emitting element 107 is formed by the combination thereof, for example, the photosensitive drum 508 of the printer 501 shown in FIG. An erecting equal-magnification image is formed on the latent image surface of.

  The partition light-shielding plate 105 as a light-shielding member is provided on the opposite side of the lens cover plate 103 with the first lens array plate 104a interposed therebetween. Further, the partition light-shielding plate 105 is arranged between the first lens array plate 104a and the second lens array plate 104b, and has a plate-like shape having an aperture serving as a diaphragm aligned with the optical axis of each microlens. Is. The partition light-shielding plate 105 shields a stray light component in a light beam emitted from the second lens array plate 104b toward the first lens array plate 104a, and separates the first lens array plate 104a and the second lens array plate 104b. It is to secure the space between them.

  The incident light shielding plate 106 shields the stray light component incident from the semiconductor light emitting element 107 to the second lens array plate 104b.

  The respective members of the lens cover plate 103, the first lens array plate 104a, the partition light-shielding plate 105, the second lens array plate 104b, and the incident light-shielding plate 106 are sandwiched by a clamp member 114 as a fixing member shown in FIG. It is fixed to each other.

  As shown in FIG. 3, the lens cover plate 103 of the lens unit 102, the first lens array plate 104a, and the partition light-shielding plate 105 are provided at a plurality of locations including the central portion in the longitudinal direction of the print head 101 shown in FIG. 1B. The second lens array plate 104b and the incident light shielding plate 106 are clamp members at the clamp portion 114a at both ends in the stacking direction and the direction orthogonal to the longitudinal direction of the lens unit 102 (the lateral direction of the lens unit 102). They are sandwiched by 114 in the stacking direction and fixed to each other.

  Here, the clamp member 114 is a sandwiching member that is arranged in plural in the longitudinal direction of the lens unit 102 and sandwiches each member of the laminated lens unit 102 at both ends in the lateral direction.

The lens unit 102 is inserted into an upper surface opening 109a as an opening between two facing surface portions 109b of a lens holder 109 as a holding member, and a sealing material 113 seals between the lens cover plate 103 and the surface portion 109b. Then, the lens holder 109 is fixed and supported.
In the lens unit 102, the distance Lo between the surface of the semiconductor light emitting elements 107 arranged in a line on the printed wiring board 108 and the bottom extreme point of the second lens array plate 104b becomes the designed optical distance. It is adjusted and fixed.

At this time, the member stacking interface of the lens unit 102 is configured such that only the interface between the lens cover plate 103 and the first lens array plate 104a is positioned outside the upper opening 109a of the lens holder 109 (upper side in FIG. 2). To be done.
As shown in FIG. 3, the lens unit 102 is fixed to the lens holder 109 by filling an adhesive 115 between the lens holder 109 and the clamp member 114 of the lens unit 102.

  Further, as shown in FIG. 2, in the lens unit 102, the first lens array plate 104 a of the lens unit 102 and the partition light-shielding plate 105 are provided in the entire outer contour of the lens cover plate 103 except the clamp portion 114 a of the lens unit 102. The width of the second lens array plate 104b and the width of the incident light-shielding plate 106 in the lateral direction of the lens unit 102 are larger than the outer contours of the lens unit 102 by d1. Similarly, also in the longitudinal direction of the lens unit 102, the outer contour of the lens cover plate 103 is the outer contours of the first lens array plate 104 a, the partition light-shielding plate 105, the second lens array plate 104 b, and the incident light-shielding plate 106 of the lens unit 102. It is formed wider than the width d1. That is, the lens cover plate 103 is formed so as to extend beyond the first lens array plate 104a by the width d1. The width d1 can be set to 0.3 mm, for example.

  Here, when the lens unit 102 is fixed to the lens holder 109, a gap (hereinafter referred to as “clearance”) is generated between the lens unit 102 and the lens holder 109. The clearance is filled with the sealing material 113 for the purpose of preventing the amount of light of the semiconductor light emitting element 107 from leaking through this clearance and the purpose of preventing foreign matter such as toner from entering the inside of the lens holder 109 through the clearance. And seal.

  Further, the sealing material 113 not only seals the clearance between the lens unit 102 and the lens holder 109, but also, as shown in FIG. 2, the interface between the lens cover plate 103 and the first lens array plate 104a. Also sealed.

  It is desirable that the sealing material 113 is filled so as to fit within the width d1 of the protruding portion of the lens cover plate 103 with respect to the first lens array plate 104a. This is to prevent the emitted light from being obstructed by the encapsulating material 113 sticking out to the upper surface of the lens cover plate 103.

  In the clamp portion 114a shown in FIG. 3, since the interface between the lens cover plate 103 and the first lens array plate 104a is covered by the clamp member 114, the entry of foreign matter from the interface is suppressed. You can

  Therefore, at least the portion where the interface between the lens cover plate 103 and the first lens array plate 104a is not covered by the clamp member 114 needs to be sealed with the sealing material 113, but the clamp portion shown in FIG. In 114a, a film sufficient to shield only the amount of light emitted from the semiconductor light emitting element 107 propagating inside the adhesive 115 may be formed.

  As shown in FIG. 2, the printed wiring board 108 on which the semiconductor light emitting element 107 is mounted has its surface abutted against a board abutting portion 110 provided in advance on the lens holder 109 so that the direction of the optical axis 107a of the lens unit 102 is increased. Positioning (vertical direction shown in FIGS. 2 and 3) is performed.

  The printed wiring board 108 is moved to the board contact portion 110 side provided on the lens holder 109 side by the base clamp member 111 by engaging the base clamp member 111 with the clamp hole 112 provided on the side surface of the lens holder 109. It is biased and fixed.

  As described above, in the lens unit 102 of this embodiment, the plate-shaped members such as the lens cover plate 103, the first lens array plate 104a, the partition light-shielding plate 105, the second lens array plate 104b, and the incident light-shielding plate 106 are laminated. Is configured. In this embodiment, one partition light-shielding plate 105 is arranged between the first lens array plate 104a and the second lens array plate 104b, but two or more light-shielding member plates or the like are used. You may make it arrange | position a shaped member.

  Next, the laminated structure of the lens unit 102 will be described with reference to FIGS. 4 to 10.

  4 is a perspective view of a lens unit in the first embodiment, FIG. 5 is an explanatory view of a laminated structure of the lens unit in the first embodiment, and FIG. 6 is an exploded view of a laminated structure of the lens unit in the first embodiment. Is. FIG. 5 shows a state before the constituent members of the lens unit 102 are stacked. Further, FIG. 7 is an enlarged view of the region 44 in FIG.

  4, 5, and 6, the lens unit 102 includes a lens cover plate 103, a first lens array plate 104a, a partition light-shielding plate 105, a second lens array plate 104b, and an entrance in order from the top in the figure as constituent members. The light blocking plates 106 are laminated.

  The first lens array plate 104a and the second lens array plate 104b are injection-molded by the same mold, and are arranged so as to be rotationally symmetrical about the longitudinal direction of the partition light-shielding plate 105 as a rotation axis. As shown in FIG. 7, the optical axis of each lens is aligned by shifting in the longitudinal direction by a half period (P / 2) of the lens pitch P. It should be noted that the first lens array plate 104a and the second lens array plate 104b have a plurality of microlenses arranged in two rows in a zigzag pattern in the longitudinal direction. Further, the intervals between the optical axes (for example, the optical axis 102b and the optical axis 102c) of the microlenses in the same row in the longitudinal direction are arranged as a lens pitch P.

  The reason for stacking the first lens array plate 104a and the second lens array plate 104b in this manner is that the molding precision of the mold and the resin are used when the first lens array plate 104a and the second lens array plate 104b are manufactured by injection molding. This is because by aligning the flow directions, it is possible to suppress the deviation of the lens optical axes of the first lens array plate 104a and the second lens array plate 104b as much as possible. This is because the lens pitch may be slightly different from the front side of the gate toward the back side of the gate due to the influence of the fluidity of the resin during injection molding.

  With such a laminated structure of the first lens array plate 104a and the second lens array plate 104b, in the laminated structure of the lens unit 102 shown in FIG. 7, the lens cover plate 103, the first lens array plate 104a, and the partition light-shielding plate. 105, the second lens array plate 104b, and the incident light-shielding plate 106 are laminated while being shifted in the longitudinal direction by a half period (P / 2) of the lens pitch P.

  Next, an engagement structure and a clamp structure of each member forming the lens unit 102 will be described.

  It should be noted that the engaging and clamping points of each member constituting the lens unit 102 are a plurality of points including at least the central portion in the longitudinal direction of the lens unit 102 shown in FIG. 4, and in the lateral direction of the lens unit 102. On both sides.

  First, the engagement structure of each member other than the central portion in the longitudinal direction of the lens unit 102 will be described with reference to FIG. 8A and 8B are explanatory views of an engaging structure other than the central portion of the lens unit in the first embodiment, FIG. 8A is an enlarged view of a region 45 of FIG. 6, and FIG. 8B is FIG. It is an enlarged view of the area | region 42 in.

  In FIG. 8, the lens cover plate 103, the first lens array plate 104a, the partition light-shielding plate 105, the second lens array plate 104b, and the incident light-shielding plate 106 have their outer edge portions engaged with adjacent members. The convex portion 123, the concave portion 124a, the convex portion 125a, the concave portion 126a, the concave portion 126b, the convex portion 125b, the concave portion 124b, and the convex portion 127 are formed.

  That is, the convex portion 123 on the lens cover plate 103, the concave portion 124a and the convex portion 125a on the first lens array plate 104a, the concave portion 126a and the concave portion 126b on the partition light-shielding plate 105, the convex portion 125b and the concave portion 124b on the second lens array plate 104b, A convex portion 127 is formed on the incident light blocking plate 106.

  The first lens array plate 104a and the second lens array plate 104b are arranged symmetrically about the partition light-shielding plate 105, and are shifted by a half cycle (P / 2) of the lens pitch P in the longitudinal direction of the lens unit 102. Are disposed in the first lens array plate 104a, the recesses 126a provided on the outer edge of the partition light-shielding plate 105 corresponding to the protrusions 125a of the first lens array plate 104a and the partition light-shielding corresponding to the protrusions 125b of the second lens array plate 104b. The concave portion 126b provided on the outer edge portion of the plate 105 is formed so as to be shifted by a half period (P / 2) of the lens pitch P in the longitudinal direction of the lens unit 102.

  The convex portion 123, the concave portion 124a, the convex portion 125a, the concave portion 126a, the concave portion 126b, the convex portion 125b, the concave portion 124b, and the convex portion 127 which are formed in this manner are provided in the optical axis direction of each lens (the laminating direction of each member) and the lens. By engaging the unit 102 in the lateral direction, the position of each member in the optical axis direction and the lateral direction of the lens unit 102 is determined.

  The convex portion 123, the concave portion 124a, the convex portion 125a, the concave portion 126a, the concave portion 126b, the convex portion 125b, the concave portion 124b, and the convex portion are formed so that the maximum tolerances of the lens unit 102 in the optical axis direction and the lateral direction are about 10 μm. 127 is to be formed.

  Further, in the optical axis (stacking) direction of the lens cover plate 103 and the first lens array plate 104a, the convex portion 123 and the concave portion 124a as the engaging portion may directly contact each other, but the lens cover plate 103 is also possible. The outer edge of the first lens array plate 104a is preferably brought into direct contact with the positioning.

  The reason is that, as shown in FIG. 2, the contact interface between the lens cover plate 103 and the first lens array plate 104a exposed on the surface of the lens holder 109 can be blocked as much as possible.

  In the present embodiment, as shown in FIG. 8B, the convex portion 123 as the engaging portion and the concave portion 124a are prevented from directly contacting each other so that the space between the lens cover plate 103 and the first lens array plate 104a is reduced. Is configured to secure the clearance c4.

  On the other hand, the optical axis (stacking) direction of the other members, that is, the first lens array plate 104a, the partition light-shielding plate 105, the second lens array plate 104b, and the incident light-shielding plate 106, is different from the convex portion 125a and the concave portion as the engaging portion. 126a, the concave portion 126b and the convex portion 125b, and the concave portion 124b and the convex portion 127 directly contact each other for positioning. Therefore, the outer edge portions of the respective members of the first lens array plate 104a, the partition light-shielding plate 105, the second lens array plate 104b, and the incident light-shielding plate 106 do not directly abut, and a clearance c5 is secured in the stacking direction between the respective members. It has a laminated structure.

  Further, in the longitudinal direction of the lens unit 102, a clearance c1 is formed between both ends of the convex portion 123 and both ends of the concave portion 126a, and a clearance c2 is formed between both ends of the convex portion 125a and both ends of the concave portion 124a. A clearance c2 is secured between both end portions of the concave portion 124b and the convex portion 125b, and a clearance c3 is secured between both end portions of the concave portion 124b and the convex portion 127.

  This is because the lens cover plate 103, the first lens array plate 104a, the partition light-shielding plate 105, the second lens array plate 104b, and the incident light-shielding plate 106, which are the respective members constituting the lens unit 102 due to ambient temperature fluctuations or humidity fluctuations. This is because each member can freely slide in the longitudinal direction of the lens unit 102 even when a difference in expansion and contraction occurs.

  By configuring the engaging portion in this way, the bending of the lens unit 102 in the optical axis direction can be suppressed.

  The clearances c1, c2, and c3 described above are at least the members that form the lens unit 102, that is, the lens cover plate 103, the first lens array plate 104a, the partition light-shielding plate 105, the second lens array plate 104b, and the incident light-shielding plate 106. It is determined in consideration of the temperature and the coefficient of linear expansion due to water absorption.

  Next, the engagement structure of each member in the central portion in the longitudinal direction of the lens unit 102 will be described with reference to FIG. 9A and 9B are explanatory views of the engagement structure of the central portion of the lens unit in the first embodiment, FIG. 9A is an enlarged view of the region 46 of FIG. 6, and FIG. It is an enlarged view of the area | region 43.

  In FIG. 9, the lens cover plate 103, the first lens array plate 104a, the partition light-shielding plate 105, the second lens array plate 104b, and the incident light-shielding plate 106 have their outer edge portions engaged with adjacent members. The convex portion 118, the concave portion 119a, the convex portion 120a, the concave portion 121a, the concave portion 121b, the convex portion 120b, the concave portion 119b, and the convex portion 122 are formed.

  That is, the convex portion 118 on the lens cover plate 103, the concave portion 119a and the convex portion 120a on the first lens array plate 104a, the concave portion 121a and the concave portion 121b on the partition wall shading plate 105, the convex portion 120b and the concave portion 119b on the second lens array plate 104b, A convex portion 122 is formed on the incident light blocking plate 106.

  The convex portion 118 and the concave portion 119a, the convex portion 120a and the concave portion 121a, the concave portion 121b and the convex portion 120b, and the concave portion 119b and the convex portion 122 engage with each other, whereby the lens cover plate 103, the first lens array plate 104a, and the partition wall. The members of the light blocking plate 105, the second lens array plate 104b, and the incident light blocking plate 106 are positioned in the longitudinal direction and the lateral direction of the lens unit 102.

  In the present embodiment, as shown in FIG. 9B, the convex portion 118 as the engaging portion and the concave portion 119a are prevented from directly contacting each other so that the space between the lens cover plate 103 and the first lens array plate 104a is reduced. Is configured to secure the clearance c4.

  On the other hand, the optical axis (stacking) direction of the other members, that is, the first lens array plate 104a, the partition light-shielding plate 105, the second lens array plate 104b, and the incident light-shielding plate 106, is different from the convex portion 125a and the concave portion as the engaging portion. 126a, the concave portion 126b and the convex portion 125b, and the concave portion 124b and the convex portion 127 directly contact each other for positioning. Therefore, the outer edge portions of the respective members of the first lens array plate 104a, the partition light-shielding plate 105, the second lens array plate 104b, and the incident light-shielding plate 106 do not directly abut, and a clearance c5 is secured in the stacking direction between the respective members. It has a laminated structure.

  It should be noted that the convex portion 118 and the concave portion 119a, the convex portion 120a and the concave portion 121a, the concave portion 121b and the convex portion 120b, and the concave portion 119b and the convex portion 122 fit with each other without a gap, so that in the longitudinal direction of the lens unit 102, as shown in FIG. The clearances c1, c2, c3 described in b) are not secured.

  In the central portion of the lens unit 102 in the longitudinal direction, the convex portion 118, the concave portion 119a, the convex portion 120a, the concave portion 121a, the concave portion 121b, the convex portion 120b, the concave portion 119b, so that the maximum tolerance in the longitudinal direction is about 10 μm. The convex portion 122 is formed.

  In this way, by forming the convex portion 118, the concave portion 119a, the convex portion 120a, the concave portion 121a, the concave portion 121b, the convex portion 120b, the concave portion 119b, and the convex portion 122 as the engaging portion, the lens unit 102 in the longitudinal direction. A fulcrum of expansion and contraction in the longitudinal direction of the lens unit 102 is formed in the central portion.

  Next, a clamp configuration of each member of the lens unit 102 will be described based on FIG. FIG. 10 is an explanatory view of the clamp structure of the lens unit in the first embodiment, and is an enlarged view of the area 41 in FIG. The clamp structure sandwiching each member of the lens unit 102 is the same at the central portion in the longitudinal direction of the lens unit 102 and the other portions.

  In FIG. 10, the upper side of the clamp member 114 in the drawing (the upper side in the stacking direction of each member) is engaged with the recess 116 as a recess formed in the lens cover plate 103, and the lower side of the clamp member 114 in the drawing (each side). The lens cover plate 103, the first lens array plate 104a, the partition light-shielding plate 105, and the second lens array plate 104b are engaged by engaging the lower side of the member in the stacking direction) with the recess 117 as a recess formed in the incident light-shielding plate 106. , And the respective members of the incident light shielding plate 106 are clamped by the clamp member 114 and fixed to each other.

  The clamp member 114 is formed such that the length of the lens unit 102 in the longitudinal direction is L1.

  In the longitudinal direction of the lens unit 102, clearances c6 are respectively secured between the inner walls on both sides of the recess 116 formed in the lens cover plate 103 and both ends of the clamp member 114, and formed on the incident light shielding plate 106. Clearances c7 are secured between the inner walls on both sides of the recess 117 and the clamp member 114.

  The recesses 116 and the recesses 117 are recesses that are inclined so that the depths of the recesses become deeper toward the central portions of the lens cover plate 103 and the incident light blocking plate 106 in the lateral direction (the lateral direction of the lens unit 102). Has become.

  Further, the widths of the clearance c6 and the clearance c7 in the longitudinal direction of the lens unit 102 are such that when the lens holder 109 and the clamp member 114 of the lens unit 102 shown in FIG. A width is secured so that the clamp member 114 does not interfere with the lens cover plate 103 and the incident light shielding plate 106 so that the lens cover plate 103 and the incident light shielding plate 106 can freely slide.

Therefore, the clearance c6 and the clearance c7 should be determined in consideration of at least the temperature of the lens cover plate 103, the incident light blocking plate 106, and the lens holder 109 and the linear expansion coefficient due to water absorption.
Therefore, in the longitudinal direction of the lens unit 102, the width of the recess 116 is (L1 + 2 × c6), and the width of the recess 117 is (L1 + 2 × c7).

  Next, material materials of the print head 101 shown in FIG. 2 will be described.

  Acrylic resin is used for the lens cover plate 103 described above. However, in order to match the linear expansion coefficient with other members, polycarbonate or the like can be used.

  Cycloolefin polymer resin (product name: ZEONEX (registered trademark), manufactured by Nippon Zeon Co., Ltd.) is used for the first lens array plate 104a and the second lens array plate 104b. Further, an acrylic resin, a polycarbonate, or an epoxy resin can be used, but in a long structure like this example, it is desirable to use a cycloolefin polymer resin having a small water absorption rate from the viewpoint of dimensional stability. .

  Polycarbonate is used for the partition light-shielding plate 105 and the incident light-shielding plate 106. Further, although ABS (acrylonitrile butadiene styrene) resin can be used, it is desirable to match the linear expansion coefficients of the lens cover plate 103, the first lens array plate 104a, and the second lens array plate 104b as much as possible. Is preferred.

  The clamp member 114 is made of a stainless steel material for spring.

  The lens holder 109 is made of sheet metal. However, LCP (liquid crystal polymer) resin or aluminum die cast may be used.

  The printed wiring board 108 is formed by patterning copper foil using a glass cloth epoxy resin substrate as a core material.

  The semiconductor light emitting device 107 is a device in which light emitting diode devices mainly made of GaAs (gallium arsenide) are arranged in a substantially linear shape of, for example, 600 dpi (dots per inch) or 1200 dpi. You can also do it.

  Polycarbonate is used for the base clamp member 111. However, nylon or the like can also be used.

  The adhesive 115 is a UV (UltraViolet) curable resin whose main component is an acrylic resin.

  The sealing material 113 is a silicone sealing material.

  Next, an image sensor head including the lens unit of this embodiment will be described.

  FIG. 12 is a sectional view of the image sensor head in the first embodiment.

  As in the print head 101 shown in FIG. 2, the image sensor head 140 includes a lens unit 102 as shown in FIG. 12, and the lens cover plate 103, the first lens array plate 104a, and the partition wall constituting the lens unit 102. The respective members of the light shielding plate 105, the second lens array plate 104b, and the incident light shielding plate 106 are clamped in the stacking direction by the clamp member 114 in the clamp portion 114a and fixed to each other.

  A semiconductor light receiving element 149 is mounted on the printed wiring board 108.

  The semiconductor light receiving element 149 is one in which a COMS sensor or a CCD sensor manufactured on a Si substrate is arranged in a substantially linear shape of, for example, 600 dpi, 1200 dpi or 2400 dpi.

  The same parts as those of the print head 101 shown in FIG. 2 are designated by the same reference numerals, and the description thereof will be omitted.

  The operation of the above configuration will be described.

  The operation of the lens unit 102 shown in FIGS. 2 to 10 used in the print head 101 shown in FIG. 1 will be described with reference to FIGS. 1 to 10.

  The lens unit 102 has a structure in which resin plate members such as the lens cover plate 103, the first lens array plate 104a, the partition light-shielding plate 105, the second lens array plate 104b, and the incident light-shielding plate 106 are laminated, and thus When the linear expansion coefficient due to heat or water absorption of the member is different, expansion and contraction of each member occurs according to each linear expansion coefficient.

  As shown in FIG. 4, the lens unit 102 of the present embodiment includes the lens cover plate 103, the first lens array plate 104a, the partition light-shielding plate 105, the second lens array plate 104b, and the incident light-shielding plate 106, as shown in FIG. The clamp members 114 are used to sandwich and fix each other.

  Further, as shown in FIG. 8, a convex portion 123, a concave portion 124a, a convex portion 125a, a concave portion 126a, a concave portion 126b, a convex portion 125b, and a concave portion as engaging portions at portions other than the central portion in the longitudinal direction of the lens unit 102. The lens cover plate 103, the first lens array plate 104a, the partition light-shielding plate 105, the second lens array plate 104b, and the incident light-shielding plate 106 are arranged in the longitudinal direction of the lens unit 102 on the convex portion 124b and the convex portion 127. Clearances c1, c2, and c3 are secured to allow free sliding.

  Therefore, except for the central portion in the longitudinal direction of the lens unit 102, the lens cover plate 103, the first lens array plate 104a, the partition light-shielding plate 105, the second lens array plate 104b, and the incident light-shielding plate 106 are the lens unit 102. It is possible to freely slide in the longitudinal direction while being restricted only in the optical axis 107a direction (see FIG. 2) and in the lateral direction.

  Further, as shown in FIG. 9, the central portion in the longitudinal direction of the lens unit 102 has a convex portion 118, a concave portion 119a, a convex portion 120a, a concave portion 121a, a concave portion 121b, a convex portion 120b, a concave portion 119b, which serve as an engaging portion, and By engaging the respective members of the lens cover plate 103, the first lens array plate 104a, the partition light-shielding plate 105, the second lens array plate 104b, and the incident light-shielding plate 106 with the convex portion 122, the respective members become the lens unit 102. In addition to being regulated in the optical axis 107a direction (see FIG. 2) and the lateral direction, it is also regulated in the longitudinal direction of the lens unit 102, and in the central portion of the lens unit 102 in the longitudinal direction, in the longitudinal direction of the lens unit 102. A fulcrum of sliding (expansion and contraction) can be formed.

  Further, each member of the lens cover plate 103, the first lens array plate 104a, the partition light-shielding plate 105, the second lens array plate 104b, and the incident light-shielding plate 106 of the lens unit 102 is provided at a plurality of portions in the longitudinal direction of the lens unit 102. By engaging with each other, the lens unit 102 can suppress fluctuations in the lens optical axis direction due to changes in ambient temperature and humidity environment.

  Further, when the lens unit 102 is fixed to the lens holder 109 of the print head 101, the clamp member 114 and the lens holder 109 are directly adhered, so that the lens cover plate 103 and the first lens sandwiched by the clamp member 114. Each member of the array plate 104a, the partition light-shielding plate 105, the second lens array plate 104b, and the incident light-shielding plate 106 can freely slide in the clamp member 114 in the longitudinal direction of the lens unit 102.

  Therefore, even when the clamp member 114 is fixed to the lens holder 109, it is possible to suppress the warpage of the lens unit 102 in the lens optical axis direction caused by changes in the ambient temperature and the humidity environment, and at the same time, the lens unit 102 and the lens. It is possible to prevent the holder 109 from breaking.

  Further, in the print head 101 equipped with the lens unit 102 of the present embodiment, since the outer shape of the lens cover plate 103 is formed wider than the outer shape of the first lens array plate 104a by the width d1, the lens unit 102 and the lens holder 109 are formed. In the work of sealing the clearance formed between the first lens array plate 104a and the lens cover plate 103, which is a member exposed from the upper surface of the lens holder 109, it is possible to reliably seal the bonding interface. . Further, since the width d1 is secured as the protruding portion of the lens cover plate 103, the sealing material 113 can be suppressed from seeping out to the surface of the lens cover plate 103.

  Further, since the lens cover plate 103 having a width wider than that of the first lens array plate 104a is arranged in the lateral direction orthogonal to the longitudinal direction of the first lens array plate 104a, foreign matter such as dust on the lens unit 102 is arranged. Since it is possible to prevent the invasion of the lens unit 102, it is possible to stabilize the productivity of the lens unit 102.

  Here, an example in which the print head 101 shown in FIG. 1 is applied to a printer as an image forming apparatus will be described.

  FIG. 11 is a schematic side sectional view showing the structure of the printer in the first embodiment.

  In FIG. 11, a printer 501 as an image forming apparatus is an LED printer equipped with the print head 101 shown in FIG.

  The printer 501 includes four process units 502, 503, 504, and 505 that form images of yellow (Y), magenta (M), cyan (C), and black (K) using electrophotography. Have

  The process units 502, 503, 504, and 505 are arranged in the order of the process unit 502 (Y), the process unit 503 (M), the process unit 504 (C), and the process unit 505 (K) along the transport path 507 of the recording medium 506. It is arranged.

  Each of the process units 502, 503, 504, and 505 is charged with a photosensitive drum 508 as an image carrier and a charging device 509 arranged around the photosensitive drum 508 and charging the surface of the photosensitive drum 508. An exposure device 510 that selectively irradiates the surface of the photoconductor drum 508 with light to form an electrostatic latent image is provided. This exposure apparatus 510 uses the print head 101 shown in FIG. 1 as a light source.

  Further, each of the process units 502, 503, 504, and 505 includes a developing device 511 that conveys toner as a developer to the surface of the photoconductor drum 508 on which the electrostatic latent image is formed, and forms a toner image, and a photoconductor. The cleaning device 512 removes the toner remaining on the surface of the drum 508.

  The photosensitive drum 508 rotates in the direction indicated by the arrow in the figure by a drive source such as a motor and a drive mechanism such as a gear.

  Further, the printer 501 has a paper cassette 513 for accommodating a recording medium 506 such as paper, and a hopping roller 514 for separating and conveying the recording media 506 accommodated in the paper cassette 513 one by one.

  The pinch rollers 515, 516 and the recording medium 506 are sandwiched downstream of the hopping roller 514 in the conveying direction of the recording medium 506, and the skew of the recording medium 506 is corrected together with the pinch rollers 515, 516 to correct the process units 502, 503. Registration rollers 517 and 518 for conveying to 504 and 505 are arranged. The hopping roller 514 and the registration rollers 517 and 518 are connected to a drive source such as a motor and rotate in conjunction with each other.

  The printer 501 has a transfer roller 519 arranged to face the photosensitive drum 508. The transfer roller 519 is made of semiconductive rubber or the like, and the potential of the photosensitive drum 508 and the potential of the transfer roller 519 are set so that the toner image on the photosensitive drum 508 is transferred onto the recording medium 506. To be done.

  Further, the printer 501 includes a fixing device 524 that fixes the toner image transferred onto the recording medium 506 by heat and pressure, and discharge rollers 520 and 521 that discharge the recording medium 506 on which the toner image is fixed to a stacker 525 outside the device. 522, 523.

  The recording media 506 stacked on the paper cassette 513 are separated one by one by the hopping roller 514 and are conveyed. The recording medium 506 passes through the registration rollers 517 and 518 and the pinch rollers 515 and 516, and then passes through the process units 502, 503, 504, and 505 in this order. In each of the process units 502, 503, 504, and 505, the recording medium 506 passes between the photosensitive drum 508 and the transfer roller 519, the toner images of the respective colors are sequentially transferred, and the fixing device 524 heats and pressurizes the toner images. The toner image of each color is fixed on the recording medium 506. After that, the recording medium 506 is ejected to the stacker 525 by the ejection rollers 520, 521, 522, 523.

  Next, an example in which the image sensor head 140 shown in FIG. 12 is applied to an image scanner as an image reading device will be described.

  FIG. 13 is a perspective view showing the configuration of the image scanner in the first embodiment.

  In FIG. 13, an image scanner 401 includes a housing 402, an original table 409 provided on an upper surface of the housing 402 for placing an original to be read, and a lid 410 for sandwiching the original between the original table 409. Have

  Inside the housing 402, a contact image sensor head 403 having the image sensor head 140 shown in FIG. 12 is arranged. The contact image sensor head 403 is supported and attached by two guides 404 fixed to the housing 402.

  In order to slide the contact image sensor head 403 along the guide 404 in the sub scanning direction, the contact image sensor head 403 is connected to the drive belt 406 connected to the stepping motor 405.

  A control circuit 408 for controlling the contact image sensor head 403 is connected to the contact image sensor head 403 via a flexible flat cable 407.

  As described above, in the first embodiment, the lens cover plate having a width wider than that of the first lens array plate is arranged in the lateral direction of the first lens array plate. Since foreign matter such as dust can be prevented from entering, the productivity of the lens unit can be stabilized.

  Further, since the outer shape of the lens cover plate is formed wider than the outer shape of the first lens array plate, it is exposed from the upper surface of the lens holder in the work of sealing the clearance formed between the lens unit and the lens holder. The effect of being able to reliably seal the bonding interface of the members to be joined is obtained.

  Further, by forming the protruding portion of the lens cover plate, it is possible to obtain an effect that it is possible to prevent the sealing material from seeping out to the surface of the lens unit.

  14A and 14B are explanatory views of the print head in the second embodiment. FIG. 14A is a plan view of the print head 201, FIG. 14B is a sectional view taken along line XX in FIG. FIG. 14C is an enlarged view of the area 47 in FIG. 14B.

  FIG. 15 is a perspective view of a lens unit in the second embodiment, FIG. 15 (a) is a perspective view of the entire lens unit 202, and FIG. 15 (b) is an enlarged view of a region 48 in FIG. 15 (a). .

  The same parts as those in the first embodiment described above are designated by the same reference numerals, and the description thereof will be omitted.

  In FIGS. 14 and 15, the lens unit 202 of the print head 201 is the same as the lens unit 102 shown in FIG. 2 of the first embodiment, on the side opposite to the semiconductor light emitting element 107 in the optical axis 107a direction of the semiconductor light emitting element 107. The lens cover plate 203, the first lens array plate 204a, the partition light-shielding plate 205, the second lens array plate 204b, and the incident light-shielding plate 206 are laminated in this order from the upper side in the drawing.

  The lens cover plate 203, the first lens array plate 204a, the partition light-shielding plate 205, the second lens array plate 204b, and the incident light-shielding plate 206 are the lens cover plate 103 and the first lens cover plate 103 of the first embodiment shown in FIG. It corresponds to the lens array plate 104 a, the partition light-shielding plate 105, the second lens array plate 104 b, and the incident light-shielding plate 106. Further, the clamp member 214 described below is the clamp member 114 of the first embodiment shown in FIG. 3, the lens holder 209 and the sealing material 213 are the lens holder 109 and the sealing material of the first embodiment shown in FIG. It corresponds to 113.

  As shown in FIG. 15, the lens unit 202 has a plurality of locations including at least the central portion in the longitudinal direction, and the clamp members 214 are attached to both sides in the lateral direction of the lens unit 202.

  Further, the outer contour of the lens cover plate 203 is formed wider than the outer contour of the first lens array plate 204a by a width d1 as in the first embodiment.

  In the lens unit 202 of the present embodiment, the outer contour of the partition light-shielding plate 205 is formed wider than the outer contour of the first lens array plate 204a by a width d2, except where the clamp member 214 is attached. It should be noted that the width d2 is such that when the lens unit 202 is inserted in the opening 209a between the facing surface portions 209b of the lens holder 209 shown in FIG. 14 in the longitudinal direction, the outer contour of the partition light-shielding plate 205 in the lateral direction is the surface portion 209b. The width is set so that it does not interfere.

  As shown in FIG. 14, for example, the clearance c21 formed between the first lens array plate 204a of the lens unit 202 and the opening 209a of the lens holder 209 is 0.2 mm, the width d1 is 0.3 mm, and the width d2. Can be 0.1 mm.

  The lens unit 202 used in the print head 201 is fixed to the lens holder 209 as in the first embodiment. Similar to the first embodiment, in the present embodiment, the sealing material 213 is filled between the first lens array plate 204a of the lens unit 202 and the lens holder 209 so that the lens unit 202 and the lens holder 209 are separated from each other. The clearance formed therebetween is sealed, and at the same time, the laminated interface between the lens cover plate 203 and the first lens array plate 204a is sealed.

  Further, the sealing material 213 is dammed by the protruding portion 205a having the width d2 formed by the outer difference between the first lens array plate 204a and the partition light-shielding plate 205, and exudes downward from the protruding portion 205a. Is suppressed.

  As described above, in the present embodiment, the partition light-shielding plate 205 is formed wider than the first lens array plate 204a in the lateral direction orthogonal to the longitudinal direction of the first lens array plate 204a, and the respective surface portions 209b are formed. Is disposed between the first lens array plate 204a and the partition light-shielding plate 205, and the surface portion 209b and the first lens array plate 204a and the partition light-shielding plate 205 are sealed with a sealing material 213.

  The lens unit 202 and the print head 201 according to this embodiment can be made of the same materials as those of the lens unit and the print head described in the first embodiment.

  The operation of the above configuration will be described.

  The operation of the lens unit 202 used in the print head 201 shown in FIG. 14 will be described with reference to FIGS. 14 and 15.

  In the lens unit 202 of this embodiment, the protruding portion 205a having the width d2 formed by the outer difference between the first lens array plate 204a and the partition light-shielding plate 205 is provided between the first lens array plate 204a and the lens holder 209. It is prevented that the sealing material 213 filled in is drooping downward from the protruding portion 205a, efficiently sealing the clearance formed between the lens unit 202 and the lens holder 209, and the lens cover plate 203. And the laminated interface between the first lens array plate 204a and the first lens array plate 204a is sealed.

  In this embodiment, as in the first embodiment, the print head 201 can be applied to the image forming apparatus, the lens unit 202 can be used to form an image sensor head, and the image sensor head can be used. Can be applied to an image reading device.

  As described above, in the second embodiment, in addition to the effect of the first embodiment, the protruding portion is formed by the outer difference between the first lens array plate and the partition light-shielding plate. It is possible to obtain an effect that the stopper can be prevented from seeping out below the protruding portion.

  FIG. 16 is an illustration of the print head in the third embodiment. 16 (a) is a perspective view of the print head, FIG. 16 (b) is a plan view of the print head, and FIG. 16 (c) is a longitudinal central portion (region 50 shown in FIG. 16 (a)) of the print head. FIG. 6 is an enlarged view of a fixing portion between a lens unit and a holder.

  FIG. 17 is a cross-sectional view of the print head in the third embodiment and is a cross-sectional view taken along the line XX in FIG.

  FIG. 18 is a perspective view of a lens unit according to the third embodiment.

  The print head 301 and the lens unit 302 of this embodiment will be described with reference to FIGS. 16, 17 and 18.

  In the print head 301 shown in FIGS. 16 and 17, in order to easily understand the fixing structure of the lens unit 302 and the lens holder 309, a structure in which the silicone sealing material between the lens unit 302 and the lens holder 309 is omitted is used. As shown, a silicone sealant is placed between the lens unit 302 and the lens holder 309 in order to prevent foreign matter from entering the inside of the print head 301 through the gap created between the lens unit 302 and the lens holder 309. It may be provided.

  As shown in FIG. 16, the print head 301 is configured such that the lens unit 302 is fixed (held) to the lens holder 309 with an adhesive 313.

  As shown in FIG. 17, the lens unit 302 has a lens cover plate 303, a first lens array plate 304a, a partition light shielding plate 305, a second lens array plate 304b, and an incident light shielding plate 306.

  The lens cover plate 303, the first lens array plate 304a, the partition light blocking plate 305, the second lens array plate 304b, and the incident light blocking plate 306 are the lens cover plate 103, the first lens blocking plate 103, and the first light blocking plate 306 of the first embodiment shown in FIG. It corresponds to the lens array plate 104 a, the partition light-shielding plate 105, the second lens array plate 104 b, and the incident light-shielding plate 106.

  As shown in FIG. 18, the lens unit 302 includes a lens cover plate 303, a first lens array plate 304a, a partition light-shielding plate 305, a second lens array plate 304b, and an incident light-shielding plate 306, which are laminated to form a plurality of members. It is clamped by a clamp member 314 and held and fixed. Further, in the lens unit 302, the respective members laminated at the substantially central portion in the longitudinal direction are fixed by an adhesive 316 for fixing each other.

  The clamp member 314 as a fixing member of the present embodiment fixes the first lens array plate 304a to the lens cover plate 303.

  The lens unit 302 thus unitized is fixed to the lens holder 309 with an adhesive 313 as shown in FIGS. 16 and 17.

  As shown in FIG. 16A, the circular holes 308a and the long holes 308b at both ends in the longitudinal direction of the print head 301 are fitted to the protrusions provided on the printer side to position the print head 301. It is a hole for doing.

  Further, contact portions are provided near both ends of the print head 301 in the longitudinal direction. The contact part of the print head 301 contacts the contact part formed on the printer side, whereby the latent image surface 508a of the photosensitive drum in the direction of the lens optical axis 107a shown in FIG. 17 and the first lens array plate 304a. Positioning is performed so that the distance Li from the upper extreme point of is the designed optical distance.

  By providing an eccentric cam mechanism at the contact portion of the print head 301, a mechanism that can adjust the distance Li to be the optical design distance can be provided.

  As shown in FIG. 17, the lens unit 302 is fixed to the lens holder 309 by bonding an adhesive 313 via a clamp member 314 at a slit portion 309a on the upper surface of the lens holder 309.

  The fixing height of the lens unit 302 to the lens holder 309 is, as shown in FIG. 17, the surface of the semiconductor light emitting elements 107 arranged in a row in the longitudinal direction on the printed wiring board 108 and the second lens in the lens unit 302. The distance Lo to the bottom surface extreme point of the array plate 304b is adjusted to be the designed optical distance.

  Here, the lens unit 302 will be described.

  The lens unit 302 includes a lens cover plate 303, a first lens array plate 304a, a partition light-shielding plate 305, a second lens array plate 304b, and an incident light-shielding plate 306, which are stacked from the latent image surface 508a side of the photosensitive drum. have.

  The lens cover plate 303 serving as a protection member is disposed so as to be laminated on the first lens array plate 304a, covers the first lens array plate 304a, and protects the lens unit 302. The lens cover plate 303 is formed wider than the first lens array plate 304a in the lateral direction orthogonal to the longitudinal direction of the first lens array plate 304a.

  The first lens array plate 304a and the second lens array plate 304b as lens members are plate-shaped in which a plurality of microlenses as lenses are arranged in rows in the longitudinal direction. The first lens array plate 304a and the second lens array plate 304b are arranged so that the optical axes of the respective microlenses are aligned with each other, and by combining them, the image of the semiconductor light emitting element 107 is erected on the latent image surface 508a of the photosensitive drum. A double image is formed.

  The partition light-shielding plate 305 as a light-shielding member is provided on the opposite side of the lens cover plate 303 with the first lens array plate 304a interposed therebetween. Further, the partition light-shielding plate 305 is a plate-like member that is arranged between the first lens array plate 304a and the second lens array plate 304b, and has an aperture as a diaphragm formed in accordance with the optical axis of each microlens. Is. The partition light-shielding plate 305 shields a stray light component in a light beam emitted from the second lens array plate 304b toward the first lens array plate 304a, and serves as a first lens array plate 304a and a second lens array plate 304b. It is to secure the space between them.

  The incident light shielding plate 306 shields the stray light component incident from the semiconductor light emitting element 107 to the second lens array plate 304b.

  The respective members of the lens cover plate 303, the first lens array plate 304a, the partition light-shielding plate 305, the second lens array plate 304b, and the incident light-shielding plate 306 are sandwiched by clamp members 314 and fixed to each other.

  The printed wiring board 108 on which the semiconductor light emitting element 107 is mounted is brought into contact with the board shown in FIG. 17 so that the distance Lo from the lower surface extreme point of the second lens array plate 304b in the lens unit 302 becomes the designed optical distance. Positioning is performed by bringing the portion 310 and the surface of the printed wiring board 108 into contact with each other.

  The printed wiring board 108 is fixed by being clamped to the board contact portion 310 provided on the lens holder 309 side by engaging the base clamp member 111 shown in FIG. 17 with the clamp hole provided on the side surface of the lens holder 309. To be done.

  Next, the laminated structure of the lens unit 302 will be described with reference to FIGS. 18 to 24.

  First, FIG. 18 is a perspective view of a lens unit in the third embodiment.

  At the central portion in the longitudinal direction of the lens unit 302 shown in FIG. 18, the respective constituent members of the lens unit 302 are fixed to each other by an adhesive 316, and at a plurality of positions in the longitudinal direction of the lens unit 302, the lens unit 302 is clamped by the clamp members 314. The constituent members are sandwiched in a laminated state.

  FIG. 19 is an explanatory view of the laminated structure of the lens unit in the third embodiment, and FIG. 20 is an enlarged view (enlarged view of a region 51 in FIG. 19) of the laminated structure of the lens unit in the third embodiment. The state before stacking the respective constituent members 302 is shown.

  19 and 20, in the lens unit 302, a lens cover plate 303, a first lens array plate 304a, a partition light-shielding plate 305, a second lens array plate 304b, and an incident light-shielding plate 306 are laminated in this order from the top as constituent members. ,It is configured.

  The first lens array plate 304a and the second lens array plate 304b are preferably injection-molded by the same mold, and are arranged so as to be rotationally symmetric with respect to the longitudinal direction of the partition light-shielding plate 305 as a rotation axis. The optical axis of the lens is adjusted.

  FIG. 20 is an enlarged view of the laminated structure of the lens unit in the third embodiment, and is an enlarged view of the region 51 at the central portion in the longitudinal direction of the lens unit 302 in FIG. FIG. 21 is an enlarged view of a laminated state of the lens unit in the third embodiment, and is a diagram showing a state in which the respective members of the lens unit shown in FIG. 20 are laminated.

  20 and 21, in the vicinity of the central portion in the longitudinal direction of the lens unit 302 shown in FIG. 19, the outer peripheral edge portion of the lens cover plate 303 and the apertures in which the diaphragms in the partition light-shielding plate 305 and the incident light-shielding plate 306 are arranged. Engagement that regulates and positions the longitudinal direction of each member at the outer peripheral edge of the region and further at the outer peripheral edge of the region where the lens arrays are arranged in the first lens array plate 304a and the second lens array plate 304b. Grooves 323a as parts, recesses 325a, 325b, 326a, 326b as engaging parts, and convex parts 3241a, 3241b, 3242a, 3242b as engaging parts are formed.

  When the groove 323a and the concave portions 325a, 325b, 326a and the convex portions 3241a, 3241b, 3242a, 3242b are fitted to each other as shown in FIG. 21, the respective members are engaged with each other in the longitudinal direction, For example, the positioning can be performed with high accuracy so that the maximum tolerance is about 10 μm.

  The groove 323a is on the outer peripheral edge of the lens cover plate 303, the recesses 325a and 325b are on the outer peripheral edge of the partition light-shielding plate 305, the recesses 326a and 326b are on the outer peripheral edge of the incident light-shielding plate 306, and the convex portions 3241a and 3241b are the first. The convex portions 3242a and 3242b are formed on the outer peripheral edge of the first lens array plate 304a, and the convex portions 3242a and 3242b are formed on the outer peripheral edge of the second lens array plate 304b.

  22 is an enlarged view of the laminated structure of the lens unit in the third embodiment, and is an enlarged view of a region 52 other than the central portion in the longitudinal direction of the lens unit 302 in FIG. FIG. 23 is an enlarged view of a laminated state of the lens unit in the third embodiment, and is a diagram showing a state in which each member of the lens unit shown in FIG. 22 is laminated.

  22 and 23, the outer peripheral edge portion of the lens cover plate 303 and diaphragms in the partition light-shielding plate 305 and the incident light-shielding plate 306 are arranged at a plurality of locations other than the central portion in the longitudinal direction of the lens unit 302 shown in FIG. In the outer peripheral edge of the aperture area and the outer peripheral edge of the area in which the lens arrays are arranged in the first lens array plate 304a and the second lens array plate 304b, the lateral direction and the optical axis direction of each member. Convex portions 323b, 323c, 325c, 325d, 325e, 325f, 326c, 326d serving as engaging portions for restricting and positioning are formed, and concave portions 3241c, 3241d, 3242c, 3242d serving as engaging portions are formed.

  As shown in FIG. 23, when the convex portions 323b, 323c, 325c, 325d, 325e, 325f, 326c, 326d and the concave portions 3241c, 3241d, 3242c, 3242d are fitted to each other, the respective members are mutually fitted. They are engaged with each other and are fitted and laminated with high precision in the lateral direction and the optical axis direction so that the maximum tolerance is, for example, about 10 μm.

  The convex portions 323b and 323c are on the outer peripheral edge portion of the lens cover plate 303, the convex portions 325c, 325d, 325e and 325f are on the outer peripheral edge portion of the partition light-shielding plate 305, and the convex portions 326c and 326d are the outer peripheral edge portion of the incident light-shielding plate 306. The recesses 3241c and 3241d are formed on the outer peripheral edge of the first lens array plate 304a, and the recesses 3242c and 3242d are formed on the outer peripheral edge of the second lens array plate 304b.

  Also, after laminating each member on the side surfaces of the ribs of the lens cover plate 303, the first lens array plate 304a, the partition light-shielding plate 305, the second lens array plate 304b, and the incident light-shielding plate 306, the adhesive shown in FIG. In order to be able to bond and fix each member with the agent 336, recesses 323j, 3241e, 325g, 3242e, 326e shown in FIG. 20 that extend in the stacking direction on the side surface of each member and in which the adhesive 336 is loaded are formed.

  FIG. 24 is an explanatory view of a clamp structure of a lens unit in the third embodiment, and is a view showing a state in which each member of the lens unit shown in FIG. 23 is clamped and fixed by a clamp member.

  A plurality of portions other than the central portion in the longitudinal direction of the lens unit 302 shown in FIG. 19 may have a lens cover plate 303, a first lens array plate 304a, a partition wall depending on the temperature and humidity environment around the print head 301 (see FIG. 16). In consideration of the occurrence of expansion and contraction depending on the linear expansion coefficient of each material of the light blocking plate 305, the second lens array plate 304b, and the incident light blocking plate 306, in the present embodiment, the respective members are fixed to each other with an adhesive. Instead of engaging each other at the engaging portion, the lateral direction orthogonal to the longitudinal direction of each member and the optical axis direction of the lens are regulated, and the lens unit 302 freely slides in the longitudinal direction. I am able to do it.

  As shown in FIG. 23, sliding protrusions 323b, 323c, 325c, 325d, 325e, 325f, 326c, 326d as engaging portions and sliding concave portions 3241c as engaging portions are provided on the outer peripheral edge portion of each member. , 3241d, 3242c, and 3242d are formed.

  The sliding concave portions 3241c, 3241d, 3242c, 3242d are formed so as to correspond to the sliding convex portions 323b, 323c, 325c, 325d, 325e, 325f, 326c, 326d.

  In addition, the sliding convex portions 323b, 323c, 325c, 325d, 325e, 325f, 326c, 326d and the sliding concave portions 3241c, 3241d, 3242c, 3242d are fitted to each other in the longitudinal direction of the lens unit 302. In order to allow free sliding only, the dimensions of the sliding concave portions 3241c, 3241d, 3242c, 3242d in the longitudinal direction of the lens unit 302 are the same as those of the sliding convex portions 323b, 323c, 325c, 325d, 325e, 325f, 326c. It is formed to be longer than the longitudinal dimension of the lens unit 302 of 326d by the slidable distance.

  As described above, in the present embodiment, a plurality of sliding projections 323b, 323c, 325c, 325d, 325e, 325f, 326c, 326d arranged in the longitudinal direction of the lens unit 302, and sliding recesses 3241c, 3241d, 3242c, The fitting structure 330 is formed by 3242d, and the respective members of the laminated lens unit 302 are engaged with each other so that the optical axes of the respective lenses are aligned.

  As shown in FIG. 24, the clamp member 314 is formed on the concave portion 323d formed on the outer edge portion of the lens cover plate 303 and on the outer edge portion of the incident light shielding plate 306 so as to cover the fitting structure 330 shown in FIG. The recessed portion 326f is fitted and attached. The clamp member 314 is arranged at a position corresponding to at least one fitting structure 330 in the longitudinal direction of the lens unit, and sandwiches all the laminated members at both ends in the lateral direction.

  The recesses 323d and 326f, which are engaging portions that engage with and come into contact with the clamp member 314, prevent the clamp member 314 from coming off, so that the recess amount increases toward the center of the lens unit 302 in the lateral direction. It is formed in a tapered shape.

  Further, in the longitudinal direction of the lens unit 302, both ends of the clamp member 314 and the recesses 323d, 326f are provided so that a clearance c8 is provided between the end of the clamp member 314 and the end of the recesses 323d, 326f. End portions are formed and the clamp member 314 is fitted therein.

  As described above, the clamp member 314 and the recesses 323d and 326f are formed when the lens unit 302 expands and contracts in the longitudinal direction due to the ambient temperature and humidity environment of the print head 301 (see FIG. 16) used. This is for absorbing the amount of displacement caused by the difference in linear expansion coefficient from 309, the clamp member 314, the lens cover plate 303, the first lens array plate 304a, the partition light-shielding plate 305, the second lens array plate 304b, and the incident light. The light shielding plate 306 is allowed to freely slide with each member.

  The clearance c8 is determined in consideration of the temperature of the lens cover plate 303, the partition light-shielding plate 305, the incident light-shielding plate 306, and the lens holder 309 which form the lens unit 302 shown in FIG. 17, and the linear expansion coefficient due to water absorption. It

  Here, the configuration of the recess 323d formed in the lens cover plate 303 will be described with reference to FIGS. 25, 26 and 27.

  FIG. 25 is a perspective view of the recess of the lens cover plate in the third embodiment, and FIGS. 26 and 27 are sectional views of the recess of the lens cover plate in the third embodiment. 26 is a sectional view taken along the line EE in FIG. 25, and FIG. 27 is a sectional view taken along the line FF in FIG.

  25, 26, and 27, the width W1 in the lateral direction of the lens cover plate 303 is defined by the lateral width of the first lens array plate 304a, the partition light-shielding plate 305, the second lens array plate 304b, and the incident light-shielding plate 306. It is formed larger than the width W2 in the direction.

  The recesses 323d are formed at both ends in the lateral direction of the lens cover plate 303, and the lens cover plate 303, the first lens array plate 304a, the partition light shielding plate 305, the second lens array plate 304b, and the incident light shielding plate that are stacked. A clamp member 314 that holds each member of 306 is engaged.

  At both ends in the longitudinal direction of each recess 323d, an inclined portion 323e with which the tip end 314a of the clamp member 314 abuts is formed.

  As shown in FIG. 26, the inclined portion 323e is formed so that the center portion in the lateral direction of the lens cover plate 303 is higher in the stacking direction of the respective members, and the tip portion of the clamp member 314 inserted into the recess 323d. Guide 314a.

  Further, a taper portion 323g is formed which is recessed toward the center side from the inclined portion 323e in the lateral direction of the lens cover plate 303. The tapered portion 323g is formed so as to be continuous with the inclined portion 323e, and holds the tip portion 314a of the clamp member 314 guided by the inclined portion 323e so as not to come off from the concave portion 323d.

  As described above, in the present embodiment, the concave portion 323d as the engaging portion and the inclined portion 323e as the first inclined portion that is convexly inclined toward the central portion of the lens cover plate 303 in the lateral direction, and the inclined portion It has a taper portion 323g as a second inclined portion that inclines concavely from the portion 323e toward the central portion in the lateral direction.

  As shown in FIG. 25, a notch portion 323f having a width W3 is formed between two inclined portions 323e in the longitudinal direction of the lens cover plate 303, and the width W3 is a fitting clamp member. It is formed wider than the width W4 between the two notches 314c of 314.

  Further, as shown in FIG. 27, the depth of each cutout portion 323f in the lateral direction of the lens cover plate 303 is such that the lens cover plate 303, the first lens array plate 304a, the partition light-shielding plate 305, and the second lens array. The plate 304b and the side surface of each member of the incident light shielding plate 306 in the lateral direction are formed to have a depth W3a so as to form the same surface.

  As described above, in this embodiment, the inclined portions 323e are formed on one end side and the other end side of the clamp member 314 in the longitudinal direction of the lens cover plate 303 (one end side and the other end side in the longitudinal direction of the lens cover plate 303). It is formed as two inclined portions that come into contact with the front end portion 314a serving as the front end contact portion, and a cutout portion 323f is formed between the two inclined portions.

  Further, the tapered portion 323g is formed so as to be continuous in the longitudinal direction of the lens cover plate 303, and even in a region where the inclined portion 323e is cut out (a region corresponding to the cutout portion 323f), the tapered portion 323g is formed. Abutting.

  In this embodiment, the width W1 in the lateral direction of the lens cover plate 303 is set to be the width in the lateral direction of the first lens array plate 304a, the partition light-shielding plate 305, the second lens array plate 304b, and the incident light-shielding plate 306. Although the width of the incident light shielding plate 306 in the lateral direction is set to be larger than W2, the lateral direction of the lens cover plate 303, the first lens array plate 304a, the partition light shielding plate 305, and the second lens array plate 304b. It may be formed to have a width larger than the width. That is, the width of the uppermost or lowermost member of the lens unit 302 forming the recess 323d in the lateral direction may be set to be larger than the width of the other members in the lateral direction.

  Next, the structure of the clamp member will be described based on the explanatory view of the clamp member in the third embodiment of FIG.

  In FIG. 28, the clamp member 314 has a tip portion 314a that engages with the recess 323d (see FIG. 23) of the lens cover plate 303 and a tip portion 314b that engages with the recess 326f (see FIG. 23). .

  The opening width h1 between the front end portion 314a and the front end portion 314b of the clamp member 314 is the lens cover plate 303, the first lens array plate 304a, the partition light-shielding plate 305, and the second partition light shielding plate 305 as the stacked members shown in FIG. It is set to be narrower than the width (height) h2 of the lens array plate 304b and the incident light blocking plate 306.

  Therefore, by inserting the tip end portion 314a and the tip end portion 314b of the clamp member 314 into each laminated member of the lens unit 302, the tip end portion 314a and the tip end portion 314b of the clamp member 314 bend, and the tip end portion 314a and the tip end portion 314a and the tip end portion 314b are bent. By sandwiching the respective members laminated by the portion 314b, the respective members are held and fixed.

  Further, at both ends of the clamp member 314 in the vertical direction in the drawing (the stacking direction of each member shown in FIG. 27), two cutouts 314c continuous with the tip 314a and two cutouts continuous with the tip 314b are provided. 314c is formed.

  A narrow portion 314d holding a width W4 is formed between two notch portions 314c continuous with the tip end portion 314a of the clamp material 314, corresponding to the notch portion 323f shown in FIG.

In the present embodiment, the cutout portions 314c are formed at both ends of the clamp member 314 in the vertical direction in the drawing, but they may be formed at either one of the end portions.
Further, the lens unit 302 and the print head 301 according to this embodiment can be made of the same material as that of the lens unit and the print head described in the first embodiment.

  The operation of the above configuration will be described.

  The operation of the lens unit 302 used in the print head 301 shown in FIGS. 16 and 17 will be described with reference to FIGS. 29 to 32.

  FIG. 29 is an explanatory view of the operation of fitting the clamp member into the lens unit in the third embodiment, and FIG. 29 (b) is an enlarged view of the area 52 in FIG. 29 (a). FIG. 30 is a sectional view of the lens unit and the clamp member in the third embodiment, and is a sectional view taken along the line GG in FIG. 29 (a).

  FIG. 31 is an explanatory diagram after the clamp member according to the third embodiment is fitted into the lens unit, and FIG. 31 (b) is an enlarged view of the region 53 in FIG. 31 (a). 32 is a cross-sectional view of the lens unit and the clamp member in the third embodiment, and is a cross-sectional view taken along the line H-H in FIG. 31 (a).

  As shown in FIGS. 29 and 30, first, one (lower) tip end portion of the clamp member 314 is formed in the concave portion 306d formed in the incident light shielding plate 306 arranged in the lowermost layer of the lens unit 302 in which the respective members are stacked. 314b is brought into contact, and the clamp member 314 is rotated toward the central portion side in the lateral direction of the lens unit 302 with the ridge line portion of the tip portion 314b brought into contact with the concave portion 306d as a fulcrum of rotation.

  When the clamp member 314 is rotated, the tip portion 314a formed on the other side (upper side) of the clamp member 314 contacts the inclined portion 323e formed on the lens cover plate 303.

  Further, when the clamp member 314 is pushed toward the center portion side in the lateral direction of the lens unit 302, the clamp member 314 bends, the tip portion 314a of the clamp member 314 is guided along the inclined portion 323e, and the tip portion 314a. When passing through the top of the inclined portion 323e and further past the tapered portion 323g, the tip end 314a of the clamp member 314 reaches the lowermost portion 323h of the recess 323d as shown in FIG.

  The inclined portion 323e deforms the tip end portion 314a in the laminating direction of the lens cover plate 303 and the first lens array plate 304a so as to open, and the taper portion 323g pulls in the tip end portion 314a, so that the lens cover plate 303 is extended in the lateral direction. I will guide you toward the central part of.

  When the tip portion 314a of the clamp member 314 reaches the lowermost portion 323h of the recess 323d, the cutout portion 323f and the narrow portion 314d correspond to each other, and the clamp member 314 causes the first lens array plate 304a of the lens unit 302, the partition light-shielding plate. The members 305, the second lens array plate 304b, and the incident light-shielding plate 306 are arranged so as to sandwich each member, and the end faces in the lateral direction of each member are flush with each other and face the surface portion 314e of the clamp member 314.

  As shown in FIGS. 31 and 32, when the tip end portion 314a of the clamp member 314 reaches the lowermost portion 323h of the recess 323d, each member of the laminated lens unit 302 is sandwiched by the clamp member 314, and the force is applied to the lamination. The state is retained and fixed.

  Further, when the tip portion 314a of the clamp member 314 reaches the lowermost portion 323h of the recess 323d, the cutout portion 314c formed in the clamp member 314 avoids the inclined portion 323e formed in the lens cover plate 303, and the clamp member 314 is formed. The front end portion 314a of the above is housed in the recess 323d of the lens cover plate 303.

  As shown in FIG. 17, the lens unit 302 in which each member is sandwiched and held by the clamp member 314 is adhered to the lens holder 309 via the clamp member 314 at the slit portion 309a on the upper surface of the lens holder 309. The agent 313 is adhered and fixed.

  As described above, in the present embodiment, the width in the lateral direction of one of the lowermost layer and the uppermost layer of the lens unit 302 in which a plurality of members are stacked is made larger than the width in the lateral direction of the other members. By forming the inclined portion 323e with which the tip end portion 314a of the clamp member 314 abuts when the clamp member 314 is fitted, the tip portion 314a of the clamp member 314 to be fitted is guided by the inclined portion 323e and the clamp portion 323e is provided. The member 314 can be flexed.

  Therefore, each member of the lens unit 302 can be easily clamped by the clamp member 314, and the lens unit 302 can be easily assembled. Furthermore, since the number of steps for assembling the lens unit 302 can be reduced, it is possible to provide the print head 301 as an inexpensive exposure apparatus.

  In addition, the width of the clamp member 314 (width W4 of the narrow portion 314d shown in FIG. 28) is larger than the width of the clamp member 314 between the two inclined portions 323e formed on one of the lowermost layer and the uppermost layer of the lens unit 302. A cutout portion 323f having a width (width W3 shown in FIG. 25) is formed, and the depth of the cutout portion 323f in the lateral direction of the lens unit 302 is set to the lens cover plate 303, the first lens array plate 304a, and the partition light-shielding plate. By setting the respective members of 305, the second lens array plate 304b, and the incident light shielding plate 306 to form the same surface, the opening width of the lens holder 309 into which the lens unit 302 is inserted can be narrowed, and the print The size of the head 301 can be reduced.

  Further, by forming the notches 314c in the upper and lower ends of the clamp member 314, it is possible to secure a sufficient width of the clamp member 314 in the longitudinal direction of the lens unit 302, and to stack the stacked lenses. Each member of the unit 302 can be held and fixed by being sandwiched by a sufficient force. Therefore, it is possible to make the lens unit 302 less susceptible to environmental changes such as temperature and humidity and changes over time.

  Further, as in the first embodiment, since the lens cover plate 303 having a width wider than that of the first lens array plate 304a is arranged in the lateral direction orthogonal to the longitudinal direction of the first lens array plate 304a, Since foreign matter such as dust can be prevented from entering the lens unit 302, the productivity of the lens unit 302 can be stabilized.

  In the present embodiment as well, as in the first embodiment, the print head 301 can be applied to the image forming apparatus, and the image sensor head can be configured by using the lens unit 302. Can be applied to an image reading device.

  As described above, in the third embodiment, the lens cover plate that is wider than the first lens array plate is arranged in the lateral direction of the first lens array plate. The foreign matter such as dust can be prevented from entering, and the productivity of the lens unit can be stabilized.

  In addition, the tip of the clamp member fitted into the lens unit can be guided by the inclined portion, and the clamp member can be bent. Therefore, each member of the lens unit can be easily clamped by the clamp member. The effect that it can be easily assembled is obtained.

  Further, the opening width of the lens holder into which the lens unit is inserted can be narrowed, and the print head can be downsized.

  In addition, each member of the laminated lens units can be sandwiched with a sufficient force, held and fixed, and it is possible to obtain an effect that it is less likely to be affected by environmental changes such as temperature and humidity of the lens units and temporal changes. To be

  Although the image forming apparatus has been described as a printer in the first to third embodiments, the invention is not limited to this, and may be a copying machine, a facsimile machine, a multi-function peripheral (MFP), or the like.

  Further, although the image forming apparatus has been described as a direct transfer type printer, the invention is not limited thereto, and may be an intermediate transfer type printer having an intermediate transfer body, a copying machine, a facsimile apparatus, a multifunction peripheral (MFP), or the like.

  Further, although the image reading device is described as an image scanner, the image reading device is not limited to this, and may be a copying machine, a facsimile device, a multi-function peripheral (MFP), or the like.

  Further, although the clamp member for sandwiching the laminated lens units is formed of the stainless steel material for the spring, the clamp member may be formed of a plastic material formed by injection molding.

101, 201, 301 Print heads 102, 202, 302 Lens units 103, 203, 303 Lens cover plates 104a, 204a, 304a First lens array plates 104b, 204b, 304b Second lens array plates 105, 205, 305 Partition light-shielding plates 106, 206, 306 Incident light shielding plate 107 Semiconductor light emitting element 108 Printed wiring board 109, 209, 309 Lens holder 110, 310 Substrate abutting portion 111 Base clamp member 113, 213 Sealing material 114, 214, 314 Clamp member 115, 313 316 Adhesive 118, 120a, 120b, 122, 123, 125a, 125b, 127, 323b, 323c, 3241a, 3241b, 3242a, 3242b, 326 326d convex portion 119a, 119b, 121a, 121b, 124a, 124b, 126a, 126b, 323d, 325a, 325b, 326a, 326b, 326f concave portion 140 image sensor head 309a slit portion 314a, 314b tip portion 314c, 323f cutout portion 314d Narrow part 323a Groove 323e Inclined part 323g Tapered part 323h Bottom part 401 Image scanner 501 Printer

Claims (11)

A lens member having a plurality of microlenses arranged in the longitudinal direction,
A protective member which is disposed in a laminated manner with the lens member and covers the lens member;
A lens unit having
The lens unit is supported by a holding member having an opening,
The protective member is
Wherein in the lateral direction perpendicular to the longitudinal direction of the lens member, together with the width is wide rather than the said lens member is disposed outside the opening of the holding member,
The lens unit is characterized in that a space between a surface portion forming the opening and a protruding portion wider than the lens member is sealed with a sealing material . The lens unit according to claim 1,
A boundary portion between the lens member and the protection member is arranged outside the opening of the holding member,
The lens unit, wherein the boundary portion is also sealed with the sealing material . A lens member having a plurality of microlenses arranged in the longitudinal direction,
A protective member which is disposed in a laminated manner with the lens member and covers the lens member;
A light blocking member provided on the opposite side of the protective member with the lens member interposed therebetween;
A lens unit to have a,
The lens unit is supported by a holding member having an opening,
The protective member is formed to have a width wider than that of the lens member in a lateral direction orthogonal to the longitudinal direction of the lens member, and is sealed with a sealing material between a surface portion forming the opening. ,
The light shielding member is formed to have a width wider than that of the lens member in a lateral direction orthogonal to the longitudinal direction of the lens member,
The surface portion is disposed between the lens member and the light shielding member,
A lens unit, wherein a space between the surface portion and the lens member and the light shielding member is sealed with the sealing material. A lens member having a plurality of microlenses arranged in the longitudinal direction,
A protective member which is disposed in a laminated manner with the lens member and covers the lens member;
A fixing member for fixing the lens member to the protection member ,
Have
The protective member is
In the lateral direction orthogonal to the longitudinal direction of the lens member, the width is formed wider than the lens member , and has an engaging portion that engages with the fixing member,
The engagement portion has a first inclined portion that is convexly inclined toward a central portion in the lateral direction of the protection member, and a second inclined portion that is concavely inclined toward the central portion from the first inclined portion. have a and of the inclined portion,
The lens unit, wherein the first inclined portion is formed at a protruding portion of the protection member having a width wider than that of the lens member . The lens unit according to claim 4,
The fixing member has a tip end portion that engages with the engagement portion of the protection member,
The first inclined portion deforms the tip end portion in an opening direction in a stacking direction of the lens member and the protection member,
The lens unit, wherein the second inclined portion draws in the tip portion and guides it toward the central portion. The lens unit according to claim 5,
The first inclined portion is formed as two inclined portions that come into contact with tip abutting portions formed on one end side and the other end side of the fixing member in the longitudinal direction of the protection member,
A lens unit, wherein a notch is formed between the two inclined parts. The lens unit according to claim 6,
The second inclined portion, a lens unit, characterized in that in contact with the fixing member even in the longitudinal direction, are notched previous SL first inclined region of the protective member. A reading device comprising the lens unit according to any one of claims 1 to 7 . An LED head comprising the lens unit according to any one of claims 1 to 7 . An exposure apparatus comprising the lens unit according to any one of claims 1 to 7 . An image forming apparatus comprising the LED head according to claim 9 or the exposure device according to claim 10 .

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