JP5321638B2 - Laser scanning optical device - Google Patents

Description

  The present invention relates to a laser scanning optical apparatus.

2. Description of the Related Art Conventionally, image forming apparatuses such as laser printers and digital copying machines are equipped with a laser scanning optical device that scans a laser to expose a photosensitive member.
The laser scanning optical device is provided with a light source for irradiating a laser and a holder for holding the light source. The holder has, for example, a substantially flat plate shape, and a light source is mounted on one surface thereof. The posture of the light source is controlled by applying a force, for example, with a screw or the like in a direction orthogonal to the surface direction of the holder, and tilting the entire holder (see, for example, Patent Documents 1 and 2). ).

JP 2000-258710 A JP 2008-112111 A

By the way, in the above-mentioned laser scanning optical device, a force is directly applied in a direction orthogonal to the surface direction of the holder to control the posture of the laser, but this force may distort the entire holder. There is a risk that the accuracy of the attitude control of the light source may be hindered.
The subject of this invention is suppressing the distortion of the holder which arises when adjusting the attachment attitude | position of a light source, and improving the precision of the attitude | position control of a light source.

A laser scanning optical device according to the invention of claim 1 is provided.
A light source having a plurality of light emitting points;
A light source frame attached around the light source;
A collimator lens that converts emitted light from the light source into parallel light;
A light source holder for holding the light source via the light source frame,
The light source holder is
An accommodating recess for slidably accommodating the light source frame along the outer peripheral surface of the light source frame;
A first adjusting member housed in the housing recess so as to be rotatable around the optical axis of the collimator lens;
The light source frame is formed with at least one abutting protrusion that abuts on the first adjustment member,
At least one first taper surface that is inclined with respect to a plane perpendicular to the optical axis direction is formed on the contact surface with which the contact protrusion of the first adjustment member contacts,
By rotating the first adjustment member around the optical axis and changing the contact position between the contact protrusion and the first taper surface, the light source frame is moved along the first taper surface. It swings and the posture of the light source is adjusted.

The invention according to claim 2 is the laser scanning optical apparatus according to claim 1,
Three of the first tapered surfaces are formed,
Three contact protrusions are provided so as to contact the three first tapered surfaces, respectively.

The invention described in claim 3 is the laser scanning optical device according to claim 1 or 2,
The light source holder is:
A second adjusting member disposed on the opposite side of the abutting surface of the first adjusting member and rotatably accommodated around the optical axis of the collimator lens in the accommodating recess;
On the opposite side of the first adjustment member from the contact surface, at least one second contact protrusion that contacts the second adjustment member is formed,
At least one second tapered surface that is inclined with respect to a plane orthogonal to the optical axis direction is formed on the second contact surface with which the second contact protrusion of the second adjustment member contacts,
By rotating at least one of the first adjustment member and the second adjustment member about the optical axis and changing the contact position between the second contact protrusion and the second tapered surface, One adjusting member swings along the second tapered surface, and the posture of the light source is adjusted through the first adjusting member.

According to a fourth aspect of the present invention, in the laser scanning optical apparatus according to the third aspect,
The swing center when the light source frame swings along the first tapered surface and the swing center when the first adjustment member swings along the second tapered surface are It is characterized in that it intersects the optical axis and has different angles with respect to the optical axis.

The invention according to claim 5 is the laser scanning optical apparatus according to claim 4,
Three of the second tapered surfaces are formed,
Three second abutting protrusions are provided so as to abut on the three second tapered surfaces, respectively.

  ADVANTAGE OF THE INVENTION According to this invention, the distortion of the holder which arises when adjusting the attachment attitude | position of a light source can be suppressed, and the precision of the attitude | position control of a light source can be improved.

It is a schematic diagram which shows schematic structure of the laser scanning optical apparatus which concerns on this embodiment. It is a front view which shows schematic structure of the laser irradiation part which concerns on this embodiment. It is a perspective view of the laser irradiation part of FIG. It is sectional drawing seen from the IV-IV cutting line in FIG. It is a disassembled perspective view of the laser irradiation part of FIG. It is a perspective view which shows schematic structure of the 1st adjustment member and 2nd adjustment member which concern on this embodiment. It is a front view of the 1st adjustment member of FIG. 6, and the 2nd adjustment member.

  The best mode for carrying out the present invention will be described below with reference to the drawings. However, although various technically preferable limitations for implementing the present invention are given to the embodiments described below, the scope of the invention is not limited to the following embodiments and illustrated examples.

  FIG. 1 is a schematic diagram showing a schematic configuration of a laser scanning optical apparatus according to the present embodiment. As shown in FIG. 1, the laser scanning optical device 1 irradiates a photoconductor 2 with a laser to expose the photoconductor 2. The laser scanning optical device 1 includes a laser irradiation unit 10 that irradiates a laser, a first optical system 3 that converts divergent light generated by the laser irradiation unit 10 into parallel light, and parallel light converted by the first optical system 3. Is converted into convergent light only in the sub-scanning direction, a polarizer 5 that polarizes the convergent light converted by the second optical system 4, and a laser beam after polarization is condensed on the photoreceptor 2. The third optical system 6 is provided with a fourth optical system 7 and a sensor 8 for adjusting the timing of the writing start position, and these are held by the optical housing 9.

  2 is a front view showing a schematic configuration of the laser irradiation unit 10, FIG. 3 is a perspective view of the laser irradiation unit 10, FIG. 4 is a cross-sectional view taken along the IV-IV cutting line in FIG. 2, and FIG. FIG. As shown in FIGS. 2 to 5, the laser irradiation unit 10 includes a main body unit 11, a lens holder 12 that holds a collimator lens as the first optical system 3, a light source 13, and a light source holder that holds the light source 13. 14.

  The main body 11 holds the lens holder 12 and the light source holder 14 so that the first optical system 3 and the light source 13 face each other. The main body 11 is formed with a guide rail 111 for sliding the lens holder 12 along the optical axis.

  The lens holder 12 is in a cylindrical state, and the first optical system 3 is accommodated therein. The lens holder 12 is slidable along the optical axis by the guide rail 111. As a result, the distance between the first optical system 3 and the light source 13 can be adjusted.

The light source 13 has a plurality of light emitters 131, which are arranged in a line from the front side to the back side of FIG. 4, for example. A light source frame 15 is attached around the light source 13.
The light source frame 15 is formed in a ring shape having an outer diameter substantially the same as the inner diameter of an accommodating recess 16 described later, and three contact protrusions 151 are circumferentially provided on the main surface on the first optical system 3 side. Are formed at predetermined intervals. Further, the outer peripheral surface of the light source frame 15 is a curved surface that is slightly convex outward.

  The light source holder 14 includes a housing recess 16 that houses the light source frame 15, a first adjustment member 17 and a second adjustment member 18 that are housed in the housing recess 16, and a light source frame that is housed in the housing recess 16. A lid member 19 that covers the body 15 is provided.

  The housing recess 16 is recessed in a cylindrical shape, and a slit 161 is formed along the axial direction at a part of the peripheral edge. In addition, a passage hole 162 for allowing the laser emitted from the light source 13 to pass to the first optical system 3 is formed at the bottom of the housing recess 16. The bottom surface inside the housing recess 16 is formed in a plane perpendicular to the optical axis of the first optical system 3.

  The first adjustment member 17 and the second adjustment member 18 adjust the posture of the light source 13 by swinging the light source frame 15. The first adjustment member 17 is disposed closer to the first optical system 3 than the light source frame 15, and the second adjustment member 18 is disposed closer to the first optical system 3 than the first adjustment member 17. The first adjustment member 17 and the second adjustment member 18 are both formed in a ring shape having an outer diameter substantially the same as the inner diameter of the housing recess 16, and the optical axis of the first optical system 3 is centered in the housing recess 16. It is designed to rotate.

FIG. 6 is a perspective view showing a schematic configuration of the first adjustment member 17 and the second adjustment member 18, and FIG. 7 is a front view of the first adjustment member 17 and the second adjustment member 18. Three contact protrusions 171 and 181 are formed on the main surfaces of the first adjustment member 17 and the second adjustment member 18 on the first optical system 3 side at predetermined intervals in the circumferential direction. On the other hand, the main surface (contact surface, second contact surface) on the light source 13 side of the first adjustment member 17 and the second adjustment member 18 is inclined with respect to a plane orthogonal to the optical axis of the first optical system 3. Three tapered surfaces 172, 182 are provided.
The tapered surface 172 of the first adjustment member 17 is the first tapered surface according to the present invention. The three contact protrusions 151 of the light source frame 15 are in contact with the three tapered surfaces 172 of the first adjustment member 17 one by one.
Further, the tapered surface 182 of the second adjustment member 18 is the second tapered surface according to the present invention. The three contact protrusions 171 of the first adjustment member 17 are in contact with the three tapered surfaces 182 of the second adjustment member 18 one by one. The three contact protrusions 181 of the second adjustment member 18 are in contact with the bottom surface of the housing recess 16.

  The three tapered surfaces 172 and 182 of the first adjustment member 17 and the second adjustment member 18 will be described. The first taper surfaces 172a and 182a among the three taper surfaces 172 and 182 are inclined so as to gradually fall toward the first optical system 3 in the counterclockwise direction A1 in FIG. Of the three taper surfaces 172 and 182, the second taper surfaces 172 b and 182 b are inclined so that they gradually rise from the lower ends of the first taper surfaces 172 a and 182 a counterclockwise A1 toward the light source 13. Has been. Of the three taper surfaces 172 and 182, the third taper surfaces 172 c and 182 c are inclined so as to gradually fall toward the first optical system 3 counterclockwise from the upper ends of the second taper surfaces 172 b and 182 b. An angle is set. The joint between the lower end of the third tapered surfaces 172c and 182c and the upper end of the first tapered surfaces 172a and 182a is a step.

  The operation of the contact protrusion 151 of the light source frame 15 that contacts the first adjusting member 17 will be described. The contact protrusion 151 corresponding to the first taper surface 172a is the first protrusion 151a, the contact protrusion 151 corresponding to the second taper surface 172b is the second protrusion 151b, and the third taper surface 172c. The corresponding contact protrusion 151 is referred to as a third protrusion 151c. FIG. 6 shows a case where each contact protrusion 151 is disposed at an intermediate position of the tapered surface 172, and this state is set as a reference position.

When only the first adjustment member 17 is rotated counterclockwise A1 from the reference position, the first protrusion 151a is raised toward the light source 13 by the first taper surface 172a, and the second protrusion 151b is the second taper. The surface 172b is lowered to the first optical system 3 side, and the third protrusion 151c is raised to the light source 13 side by the third tapered surface 172c.
On the other hand, when only the first adjustment member 17 is rotated clockwise A2 from the reference position, the first protrusion 151a is lowered to the first optical system 3 side by the first tapered surface 172a, and the second protrusion 151b is The third taper surface 172b moves upward toward the light source 13, and the third protrusion 151c moves downward toward the first optical system 3 side through the third taper surface 172c.
As described above, when the first adjustment member 17 is rotated, each contact protrusion 151 moves up and down while changing the contact position with the taper surface 172, and in conjunction with this, the light source frame 15 moves the swing center B1. The light source 13 swings along the arrow C in the center.

  Next, the operation of the contact protrusion 171 of the first adjustment member 17 that contacts the second adjustment member 18 will be described. The contact protrusion 171 corresponding to the first taper surface 182a is the first protrusion 171a, the contact protrusion 171 corresponding to the second taper surface 182b is the second protrusion 171b, and the third taper surface 182c. The corresponding contact protrusion 171 is referred to as a third protrusion 171c.

When only the second adjustment member 18 is rotated counterclockwise A1 from the reference position, the first protrusion 171a is raised to the light source 13 side by the first taper surface 182a, and the second protrusion 171b is the second taper. The surface 182b is lowered to the first optical system 3 side, and the third protrusion 171c is raised to the light source 13 side by the third tapered surface 182c.
On the other hand, when only the second adjustment member 18 is rotated clockwise A2 from the reference position, the first protrusion 171a is lowered to the first optical system 3 side by the first tapered surface 182a, and the second protrusion 171b is The third taper surface 182b moves upward toward the light source 13, and the third protrusion 171c moves downward toward the first optical system 3 side through the third taper surface 182c.
As described above, when the second adjustment member 18 is rotated, each contact protrusion 181 moves up and down while changing the contact position with respect to the tapered surface 182, and in conjunction with this, the first adjustment member 17 and the light source frame 15 are moved. The light source 13 also swings along the arrow C about the swing center B2.

Here, the swing centers B1 and B2 of the first adjustment member 17 and the second adjustment member 18 correspond to the first optical member when the first adjustment member 17 and the second adjustment member 18 are disposed in the housing recess 16. It intersects the optical axis of system 3. The first adjusting member 17 and the second adjusting member 18 are disposed in the housing recess 16 so that the angles formed by the swing centers B1 and B2 and the optical axis are different from each other.
As a result, when the posture of the light source 13 is adjusted, the light source 13 can be swung by the two swing centers B1 and B2, and finer posture adjustment is possible.

  Further, the first adjusting member 17 and the second adjusting member 18 are formed with notches 173 and 183 facing the slit 161. The first adjusting member 17 or the second adjusting member 18 can be rotated by inserting a tool from the slit 161 into the notches 173 and 183 and operating the notches 173 and 183.

  And the outer peripheral surface of the 1st adjustment member 17 becomes a curved surface which becomes slightly convex toward the outer side, as shown in FIG. The curvature of this curved surface is 1 / r where r is the radius of the first adjusting member 17. The same applies to the curvature of the outer peripheral surface of the light source frame 15. Thus, since the outer peripheral surfaces of the light source frame 15 and the first adjustment member 17 are curved, when the light source frame 15 and the first adjustment member 17 swing, the inner periphery of the housing recess 16 It will slide smoothly along the surface.

Next, the operation of this embodiment will be described.
When adjusting the posture of the light source 13, the operator inserts a tool into the slit 161 and rotates at least one of the first adjustment member 17 and the second adjustment member 18. By this rotation, the light source frame 15 and the first adjustment member 17 swing, and the posture of the light source 13 changes. When the light source 13 is in a desired posture, the operator removes the tool from the slit 161.

As described above, according to the present embodiment, since the posture of the light source 13 can be controlled while the light source frame 15 is housed in the housing recess 16, the light source holder 14 is distorted during posture adjustment. It is difficult to apply such a force. In particular, at least one of the first adjustment member 17 and the second adjustment member 18 is rotated about the optical axis, and the contact positions between the contact protrusions 151 and 171 and the tapered surfaces 172 and 182 are changed, so that Since the frame body 15 swings along the tapered surfaces 172 and 182 and the posture of the light source 13 is adjusted, a force is directly applied in a direction perpendicular to the surface direction of the light source holder as in the prior art to The posture of the light source 13 can be controlled without controlling the posture. Therefore, the distortion of the light source holder 14 that occurs when the mounting posture of the light source 13 is adjusted can be suppressed, and the accuracy of posture control of the light source 13 can be improved.
In addition, since the first adjustment member 17, the second adjustment member 18, and the light source frame 15 for adjusting the posture of the light source 13 are housed in the housing recess 16 together with the light source 13, a mechanism for adjusting the posture is provided. It can be made compact as a whole. This saves space.

In addition, since the three contact protrusions 151 of the light source frame 15 are provided so as to contact the three tapered surfaces 172 of the first adjustment member 17, the light source frame 15 is in contact with the tapered surface 172. Therefore, the posture of the light source frame 15 can be stably maintained even during posture adjustment.
Similarly, since the three contact protrusions 171 of the first adjustment member 17 are provided so as to contact the three taper surfaces 182 of the second adjustment member 18, the first adjustment member 17 is formed on the taper surface 182. On the other hand, it is supported at three points, and the posture of the first adjustment member 17 can be stably maintained even during posture adjustment.
Note that the present invention is not limited to the above embodiment, and can be modified as appropriate.

DESCRIPTION OF SYMBOLS 1 Laser scanning optical apparatus 2 Photoconductor 3 First optical system (collimator lens)
DESCRIPTION OF SYMBOLS 4 2nd optical system 5 Polarizer 6 3rd optical system 7 4th optical system 8 Sensor 9 Optical housing 10 Laser irradiation part 11 Main body part 12 Lens holder 13 Light source 14 Light source holder 15 Light source frame 16 Accommodation recessed part 17 First adjustment Member 18 Second adjustment member 19 Lid member 111 Guide rail 131 Light emitter 151 Contact protrusion 161 Slit 162 Passing hole 171 Contact protrusion (second contact protrusion)
172 Tapered surface (first tapered surface)
173 Notch 181 Abutting protrusion 182 Tapered surface (second tapered surface)
183 Notch B1 Center of swing B2 Center of swing

Claims (5)

A light source having a plurality of light emitting points;
A light source frame attached around the light source;
A collimator lens that converts emitted light from the light source into parallel light;
A light source holder for holding the light source via the light source frame,
The light source holder is
An accommodating recess for slidably accommodating the light source frame along the outer peripheral surface of the light source frame;
A first adjusting member housed in the housing recess so as to be rotatable around the optical axis of the collimator lens;
The light source frame is formed with at least one abutting protrusion that abuts on the first adjustment member,
At least one first taper surface that is inclined with respect to a plane perpendicular to the optical axis direction is formed on the contact surface with which the contact protrusion of the first adjustment member contacts,
By rotating the first adjustment member around the optical axis and changing the contact position between the contact protrusion and the first taper surface, the light source frame is moved along the first taper surface. A laser scanning optical apparatus that swings and adjusts a posture of the light source. The laser scanning optical apparatus according to claim 1, wherein
Three of the first tapered surfaces are formed,
3. The laser scanning optical device according to claim 1, wherein three contact protrusions are provided so as to contact each of the three first tapered surfaces. The laser scanning optical apparatus according to claim 1 or 2,
The light source holder is:
A second adjusting member disposed on the opposite side of the abutting surface of the first adjusting member and rotatably accommodated around the optical axis of the collimator lens in the accommodating recess;
On the opposite side of the first adjustment member from the contact surface, at least one second contact protrusion that contacts the second adjustment member is formed,
At least one second tapered surface that is inclined with respect to a plane orthogonal to the optical axis direction is formed on the second contact surface with which the second contact protrusion of the second adjustment member contacts,
By rotating at least one of the first adjustment member and the second adjustment member about the optical axis and changing the contact position between the second contact protrusion and the second tapered surface, A laser scanning optical device, wherein an adjustment member swings along the second tapered surface, and an attitude of the light source is adjusted via the first adjustment member. The laser scanning optical apparatus according to claim 3, wherein
The swing center when the light source frame swings along the first tapered surface and the swing center when the first adjustment member swings along the second tapered surface are A laser scanning optical apparatus characterized by intersecting an optical axis and having different angles with respect to the optical axis. The laser scanning optical apparatus according to claim 4, wherein
Three of the second tapered surfaces are formed,
3. The laser scanning optical apparatus according to claim 3, wherein the second contact protrusions are provided in contact with the three second taper surfaces.

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