JP7797249B2 - Lens barrel and imaging device - Google Patents

Description

The present invention relates to a lens barrel and an imaging device.

Lens barrels are required to prevent misalignment of optical components due to impact or environmental fluctuations. Patent Document 1 discloses an optical device equipped with a means for fixing an optically adjusted lens holding member to a base member. Specifically, a convex portion on the lens holding member is positioned inside a through-hole portion in the base member, and with a sealing member installed in the through-hole portion, an adhesive is filled around the convex portion, thereby fixing the lens holding member to the base member.

Japanese Patent Application Laid-Open No. 2020-194104

In the optical device described in Patent Document 1, the area filled with adhesive is cylindrical, with the convex portion at its center, and the contact area between the adhesive and the convex portion is small when an impact occurs. As a result, if the optical element is heavy, the adhesive will be crushed by the impact, causing the lens holding element to shift position and reducing product performance. Furthermore, because the sealing element is not fixed to the lens holding element until the adhesive has hardened, the adhesive work must be performed in each location, reducing assembly workability.

The objective of the present invention is to provide a lens barrel that combines impact resistance with ease of assembly.

A lens barrel according to one aspect of the present invention includes a base member, a holding member that holds an optical element, a positioning member fixed to the holding member for adjusting the position of the holding member relative to the base member, and an impact-resistant member fixed to the holding member. The base member has a first hole formed therein for incorporating the impact-resistant member, and the shape of the fitting portion provided on the impact-resistant member that fits with the holding member and the fitting portion provided on the holding member that fits with the impact-resistant member are polygonal. The first hole is formed in the base member to fit the optical element. The optical member is formed from a first surface parallel to the optical axis and a second surface parallel to a plane perpendicular to the optical axis, the outer shape of the impact-resistant member is formed from a third surface parallel to the optical axis and facing the first surface, and a fourth surface parallel to a plane perpendicular to the optical axis and facing the second surface, a first gap is formed between the first surface and the third surface, and a second gap is formed between the second surface and the fourth surface, and at least one of the first gap and the second gap is filled with an adhesive.

The present invention makes it possible to provide a lens barrel that combines impact resistance with ease of assembly.

FIG. 1 is a perspective view of a camera system according to a first embodiment. FIG. 2 is an exploded perspective view of the lens unit of the first embodiment. FIG. 2 is an explanatory diagram of an impact-resistant piece according to the first embodiment. FIG. 2 is a side view of the lens unit of the first embodiment. FIG. 2 is a partial enlarged view of the lens unit of the first embodiment. FIG. 6 is a cross-sectional view of the lens unit of Example 1 taken along line AA in FIG. 5. FIG. 6 is a cross-sectional view of the lens unit of Example 1 taken along line BB in FIG. 5. FIG. 10 is a partial enlarged view of the lens unit of the second embodiment. FIG. 9 is a cross-sectional view of the lens unit of Example 2 taken along line CC in FIG. 8. FIG. 9 is a cross-sectional view of the lens unit of Example 2 taken along line DD in FIG. 8. FIG. 10 is a partial enlarged view of the lens unit of Example 3. FIG. 12 is a cross-sectional view of the lens unit of Example 3 taken along line EE in FIG. 11. FIG. 12 is a cross-sectional view of the lens unit of Example 3 taken along the line FF in FIG. 11. FIG. 10 is a partial enlarged view of the lens unit of Example 4. FIG. 15 is a cross-sectional view of the lens unit of Example 4 taken along line GG in FIG. 14. FIG. 15 is a cross-sectional view of the lens unit of Example 4 taken along line HH in FIG. 14.

Embodiments of the present invention will now be described in detail with reference to the drawings. In each drawing, identical components will be assigned the same reference numbers, and duplicate descriptions will be omitted.

Figure 1 is a perspective view of the camera system of this embodiment. The camera system includes a lens barrel 100 and a camera (imaging device) 200. The lens barrel 100 is configured to be detachable from the camera 200 via a mount (not shown). The lens barrel 100 also includes a lens unit 101. The lens barrel 100 also includes a control unit, lens drive instruction means, and contact unit capable of communicating with the camera 200 (all not shown). The camera 200 also includes a control unit, an imaging element, and contact unit capable of communicating with the lens barrel 100 (all not shown). The imaging element included in the camera 200 receives light from the lens barrel 100. The camera 200 may also be configured integrally with the lens barrel 100.

Figure 2 is an exploded perspective view of the lens unit 101 of this embodiment. The lens unit 101 includes a lens (optical element) 102, a lens holding barrel (holding member) 103, a base 104, rollers (positioning members) 105, screws 106, shock-resistant blocks (shock-resistant members) 107, and screws 108. The lens holding barrel 103 holds the lens 102. The base 104 holds the lens holding barrel 103. The rollers 105 are fixed to the lens holding barrel 105 and adjust the position of the lens holding barrel 103 relative to the base 104. The screws 106 secure the rollers 105 to the lens holding barrel 103. The shock-resistant blocks 107 absorb shocks over a wide area. The screws 108 secure the shock-resistant blocks 107 to the lens holding barrel 103. Because the shock-resistant blocks 107 are fixed with the screws 108, the gluing process is not limited to one location at a time, improving workability.

The outer periphery of the lens holding tube 103 is provided with a lens holding portion 103a, a roller fitting portion 103b, and an impact-resistant piece fitting portion (fitting portion) 103c. The shape of the impact-resistant piece fitting portion 103c is a rectangle formed by a surface 103d parallel to the optical axis 300 of the lens 102 and a surface 103e parallel to a plane perpendicular to the optical axis 300. Note that the shape of the impact-resistant piece fitting portion 103 is not limited to a rectangle, and may be any polygonal shape that allows for rotation restriction.

A roller mounting hole (second hole) 104a and an impact-resistant block mounting hole (first hole) 104b are provided on the outer periphery of the base 104. The impact-resistant block mounting hole 104b is formed by a surface (first surface) 104c parallel to the optical axis 300 and a surface (second surface) 104d parallel to a plane perpendicular to the optical axis 300. A notch (third notch) 104e is formed in part of surface 104d. Notch 104e includes a surface 104f parallel to the optical axis 300 and a surface 104g parallel to the plane perpendicular to the optical axis 300. Because the length of surface 104f is longer than the thickness of side surface 104h, when an impact is applied after the adhesive application process to notch 104e, side surface 104h elastically deforms before the adhesive is completely crushed.

After the lens holding barrel 103 is assembled into the inner periphery of the base 104, the rollers 105 are assembled from the outer periphery of the base 104 and fixed to the lens holding barrel 103 with screws 106. At this time, the outer periphery of the rollers 105 and the roller assembly holes 104a are fitted or press-fit, thereby regulating the position of the lens holding barrel 103. In this embodiment, a press-fit setting is preferred. To position the lens holding barrel 103, the outer portion of the rollers 105 that abut the roller assembly holes 104a may be coaxial with the fitting portion or may be eccentric. Therefore, the lens holding barrel 103 may be a fixed group whose position is not adjustable, or a position-adjustable group whose position is adjusted by the rotation of the rollers 105.

Figure 3 is an explanatory diagram of the shock-resistant top 107. Figures 3(a) to 3(c) are a perspective view, a front view, and a rear view, respectively, of the shock-resistant top 107. The shock-resistant top 107 has a lens holding barrel fitting portion 107a for restricting rotation when assembled into the lens holding barrel 103. The shape of the lens holding barrel fitting portion 107a is a rectangle formed by a surface 107b parallel to the optical axis 300 and a surface 107c parallel to a plane perpendicular to the optical axis 300. Note that the shape of the lens holding barrel fitting portion 107a is not limited to a rectangle, and may be any polygonal shape that allows for rotation restriction. Furthermore, when incorporated into lens holding barrel 103, shock-resistant piece 107 has an outer shape formed by outer portion (third surface) 107d that is parallel to optical axis 300 and faces surface 104c, and outer portion (fourth surface) 107e that is parallel to a plane perpendicular to optical axis 300 and faces surface 104d. Shock-resistant piece 107 also has hole 107f through which screw 108 is inserted, and notch portion (fourth notch portion) 107g formed by cutting out a portion of outer portion 107e. When incorporated into lens holding barrel 103, notch portion 107g includes surface 107h that is parallel to optical axis 300 and surface 107i that is parallel to the plane perpendicular to optical axis 300.

Figure 4 is a side view of the lens unit 101 of this embodiment. Figure 5 is a partially enlarged view of the lens unit 101 of this embodiment. Figure 6 is a cross-sectional view of the lens unit 101 of this embodiment taken along line A-A in Figure 5. Figure 7 is a cross-sectional view of the lens unit 101 of this embodiment taken along line B-B in Figure 5. The configuration of this embodiment is preferably used for fixed groups or decentering adjustment groups.

The lens holding barrel 103 is positioned in a direction parallel to the optical axis 300 and a direction perpendicular to the optical axis 300 by press-fitting three rollers 105, which are fixed with screws 106, into the base 104 at equal intervals of 120°. It is preferable that the number of rollers 105 is at least three. The lens holding barrel 103 also has six shock-resistant blocks 107 fixed with screws 108. It is preferable that the number of shock-resistant blocks 107 is at least three.

As mentioned above, the shape of the shock-resistant piece fitting portion 103c and the lens holding barrel fitting portion 107a is square, which restricts rotation around the screw 108 when the shock-resistant piece 107 is fixed with the screw 108. As a result, the surface 104c of the shock-resistant piece mounting hole 104a faces the outer portion 107d of the shock-resistant piece 107, forming a gap (first gap) 400. Because the surface 104c and the outer portion 107d are parallel to the optical axis 300, the contact area in the direction perpendicular to the optical axis 300 can be increased in the event of an impact, improving shock resistance. Furthermore, the surface 104d of the shock-resistant piece mounting hole 104a faces the outer portion 107e of the shock-resistant piece 107, forming a gap (second gap) 401. Because surface 104d and outer portion 107e are perpendicular to the optical axis, the contact area in the direction parallel to optical axis 300 can be increased in the event of an impact, improving impact resistance. At least one of gaps 400, 401 is filled with adhesive.

When the lens holding barrel 103 is an eccentricity adjustment group, gap 400 does not change and gap 401 is left open by the amount of eccentricity adjustment, allowing eccentricity adjustment without increasing resistance in directions parallel to and perpendicular to the optical axis 300. Furthermore, cutouts 104e and 107g face each other to form an adhesive groove 402. By filling gaps 400 and 401 and adhesive groove 402 with adhesive and allowing it to harden, the gap between the shock-resistant assembly hole 104b and the shock-resistant piece 107 can be eliminated and shock resistance can be improved. Adhesive groove 402 allows for a larger adhesive bonding area, improving shock resistance in particular in directions parallel to the optical axis 300.

If the lens holding barrel 103 is a fixed group whose position is not adjusted, it is preferable to provide a notch in the surface 104c and the outer portion 107d. Furthermore, if the lens holding barrel 103 is a tilt-adjustable group, it is preferable to configure the shock-resistant top 107 so that it can be assembled by rotating it 90° when viewed from the assembly direction, and to form a notch 104e in the surface 104c. Furthermore, the adhesive groove 402 may be formed in multiple locations rather than just one.

As a shock-resistant measure, it is possible to make the positioning rollers rectangular in shape, but if the lens holding barrel 103 is a position adjustment group, the positioning rollers, which have eccentric shapes, would need to be rotated. This means that the screws securing the rollers must be loosened each time the position is adjusted, reducing workability. In this embodiment, shock-resistant blocks 107 secured by screws 108 are provided separately from the rollers 105, making it possible to provide a lens barrel that combines shock resistance with ease of assembly.

The lens barrel of this embodiment differs from the lens barrel of Example 1 in the configuration of the lens unit 101. In this embodiment, a description of the configuration that is the same as in Example 1 will be omitted, and only the different configuration will be described.

Figure 8 is a partially enlarged view of the lens unit 101 of this embodiment. Figure 9 is a cross-sectional view of the lens unit of this embodiment taken along line CC in Figure 8. Figure 10 is a cross-sectional view of the lens unit of this embodiment taken along line DD in Figure 8. The configuration of this embodiment is preferably used for fixed groups or decentering adjustment groups.

In this embodiment, a cutout portion (first cutout portion) 104i is formed in a portion of surface 104c. Cutout portion 104i includes surface 104j parallel to optical axis 300 and surface 104k parallel to a plane perpendicular to optical axis 300. Outer portion 107d also includes arm portion (first arm portion) 107j extending radially of shock-resistant piece 107 (a direction parallel to optical axis 300 and a direction perpendicular to the assembly direction of shock-resistant piece 107). Gaps 403 and 404 are formed between cutout portion 104i and arm portion 107j. As shown in FIG. 9, in a plane perpendicular to optical axis 300 (as viewed from a direction parallel to optical axis 300), cutout portion 104i and arm portion 107j overlap radially of shock-resistant piece 107. When the lens holding barrel 103 is an eccentricity adjustment group, the notch 104i and the arm 107j always overlap in the radial direction of the shock-resistant piece 107 on a plane perpendicular to the optical axis 300, even at maximum eccentricity adjustment. This increases the creepage distance compared to Example 1, preventing the adhesive from wrapping around the inner diameter and improving workability. Additionally, the contact area of the adhesive can be increased compared to Example 1, improving impact resistance.

If the lens holding barrel 103 is a tilt-adjustable group, it is preferable to configure the shock-resistant top 107 so that it can be installed by rotating it 90° when viewed from the installation direction, and to form a notch 104e on the surface 104c.

The lens barrel of this embodiment differs from the lens barrels of Examples 1 and 2 in the configuration of the lens unit 101. In this embodiment, a description of the configuration that is the same as in Examples 1 and 2 will be omitted, and only the different configuration will be described.

Figure 11 is a partially enlarged view of the lens unit 101 of this embodiment. Figure 12 is a cross-sectional view of the lens unit of this embodiment taken along line E-E in Figure 11. Figure 13 is a cross-sectional view of the lens unit of this embodiment taken along line F-F in Figure 11. The configuration of this embodiment is preferably used for fixed groups or tilt-adjustable groups.

In this embodiment, a cutout portion (second cutout portion) 107k is formed in a portion of outer portion 107d. Cutout portion 107k includes a surface 107l parallel to optical axis 300 and a surface 107m parallel to a plane perpendicular to optical axis 300. Outer portion 107e also has an arm portion (second arm portion) 107n extending in a direction parallel to optical axis 300. Gaps 405 and 406 are formed between cutout portion 104e and arm portion 107n. As shown in FIG. 13 , on a plane parallel to optical axis 300 (as viewed from a direction parallel to optical axis 300 and a direction perpendicular to the assembly direction of shock-resistant piece 107), cutout portion 104e and arm portion 107n overlap in the radial direction of shock-resistant piece 107. When the lens holding barrel 103 is a tilt-adjustable group, the notch 104e and the arm 107n always overlap in the radial direction of the shock-resistant piece 107 on a plane parallel to the optical axis 300, even when adjusted to the maximum tilt. This increases the creepage distance and prevents the adhesive from wrapping around the inner diameter, improving workability. Furthermore, increasing the contact area of the adhesive also improves impact resistance.

The lens barrel of this embodiment differs from the lens barrels of Examples 1 to 3 in the configuration of the lens unit 101. In this embodiment, a description of the configuration that is the same as in Examples 1 to 3 will be omitted, and only the different configuration will be described.

Figure 14 is a partially enlarged view of the lens unit 101 of this embodiment. Figure 15 is a cross-sectional view of the lens unit of this embodiment taken along line G-G in Figure 14. Figure 16 is a cross-sectional view of the lens unit of this embodiment taken along line H-H in Figure 14. The configuration of this embodiment is preferably used for tilt adjustment groups and decentering adjustment groups.

In this embodiment, outer portion 107d includes arm 107j. Gaps 403, 404 are formed between notch 104e and arm 107j. As shown in FIG. 15, in a plane perpendicular to optical axis 300, notch 104i and arm 107j overlap in the radial direction of shock-resistant top 107. When lens holding barrel 103 is an eccentricity adjustment group, notch 104i and arm 107n always overlap in the radial direction of shock-resistant top 107 in a plane perpendicular to optical axis 300, even at maximum eccentricity adjustment.

Furthermore, outer portion 107e includes arm portion 107n. Gaps 405, 406 are formed between notch portion 104e and arm portion 107n. As shown in FIG. 15 , in a plane parallel to optical axis 300, notch portion 104e and arm portion 107n overlap in the radial direction of shock-resistant top 107. When lens holding barrel 103 is a tilt adjustment group, in a plane parallel to optical axis 300, notch portion 104e and arm portion 107n always overlap in the radial direction of shock-resistant top 107, even at maximum eccentricity adjustment.

The above configuration increases creepage distance and prevents the adhesive from wrapping around the inner diameter, improving workability. It also increases the contact area of the adhesive, improving impact resistance.

The above describes preferred embodiments of the present invention, but the present invention is not limited to these embodiments, and various modifications and variations are possible within the scope of the invention.

100 Lens barrel 102 Lens (optical member)
103 Lens holding barrel (holding member)
103c Impact-resistant piece fitting part (fitting part)
104 Base 104b Impact-resistant piece installation hole (first hole)
104c surface (first surface)
104d surface (second surface)
105 Roller (positioning member)
107 Impact-resistant piece (impact-resistant member)
107a Lens holding barrel fitting portion (fitting portion)
Surface 107d (third surface)
Surface 107e (fourth surface)
300 Optical axis 400 Gap (first gap)
401 Gap (second gap)

Claims (9)

A base member;
a holding member for holding an optical member;
a positioning member fixed to the holding member for adjusting the position of the holding member relative to the base member;
an impact resistant member fixed to the holding member,
a first hole for incorporating the impact resistant member is formed in the base member;
a fitting portion provided on the impact resistant member to be fitted with the holding member and a fitting portion provided on the holding member to be fitted with the impact resistant member each have a polygonal shape;
the first hole is formed by a first surface parallel to an optical axis of the optical member and a second surface parallel to a plane perpendicular to the optical axis,
an outer shape of the impact-resistant member is formed by a third surface that is parallel to the optical axis and faces the first surface, and a fourth surface that is parallel to a plane perpendicular to the optical axis and faces the second surface;
a first gap is formed between the first surface and the third surface;
a second gap is formed between the second surface and the fourth surface;
The lens barrel according to claim 1, wherein at least one of the first gap and the second gap is filled with an adhesive. The lens barrel according to claim 1, characterized in that the base member has a second hole formed therein for incorporating the positioning member. a first cutout portion including a surface parallel to the optical axis and a surface parallel to a plane perpendicular to the optical axis is formed in the first surface;
a second cutout portion including a surface parallel to the optical axis and a surface parallel to a plane perpendicular to the optical axis is formed in the third surface;
3. The lens barrel according to claim 1, wherein the first cutout portion and the second cutout portion face each other to form an adhesive groove. a first cutout portion including a surface parallel to the optical axis and a surface parallel to a plane perpendicular to the optical axis is formed in the first surface;
the third surface includes a first arm portion extending in a radial direction of the impact-resistant member;
3. The lens barrel according to claim 1, wherein the first arm and the first cutout overlap in the radial direction when viewed in a direction parallel to the optical axis. a third cutout portion including a surface parallel to the optical axis and a surface parallel to a plane perpendicular to the optical axis is formed in the second surface;
a fourth cutout portion including a surface parallel to the optical axis and a surface parallel to a plane perpendicular to the optical axis is formed in the fourth surface;
5. The lens barrel according to claim 1, wherein the third cutout portion and the fourth cutout portion face each other to form an adhesive groove. a third cutout portion including a surface parallel to the optical axis and a surface parallel to a plane perpendicular to the optical axis is formed in the second surface;
the fourth surface includes a second arm portion extending in a direction parallel to the optical axis,
5. The lens barrel according to claim 1, wherein the second arm portion and the third cutout portion overlap in the radial direction of the impact-resistant member when viewed in a direction parallel to the optical axis and a direction perpendicular to the direction in which the impact-resistant member is assembled into the holding member. A lens barrel according to any one of claims 1 to 6, wherein the holding member is an eccentricity adjustment group. A lens barrel according to any one of claims 1 to 7, wherein the holding member is a tilt adjustment group. The lens barrel according to any one of claims 1 to 8,
and an image sensor that receives light from the lens barrel.