JP2008122636A - Camera module - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a camera module in which large load is not imposed on an adhesive for fixing a member in a lens barrel and fatigue failure of the adhesive can be prevented as a result. <P>SOLUTION: The camera module has a lens barrel 4 holding a lens group 6 constituted by superposing a plurality of lenses in an optical axis direction inside, a diaphragm plate 33 is interposed between a first lens 30 and a second lens 31 constituting the lens group 6, and the first lens is constituted so that one surface 30c at its circumference part may abut on the lens barrel or the surface of the other lens to be positioned, and the other surface 30d at the circumference part interposes the diaphragm plate. The second lens is constituted so that one surface 31c at its circumference part may interpose the diaphragm plate and may be fixed on the lens barrel with the adhesive 34 at the periphery part. Projection parts 30e and 31e interposing the diaphragm plate respectively are formed on one-side surfaces at the circumference parts of the first lens and the second lens, and the projection part 30e of the first lens and the projection part 31e of the second lens are formed at different positions in the plane direction of the diaphragm plate. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a camera module configured by housing a lens in a housing, and more particularly to a camera module in which a lens held in a lens barrel constituting the housing is fixed with an adhesive.

  A camera module configured by housing a lens in a housing is provided with a housing on a substrate on which an image sensor is arranged, and the housing is fixed to the substrate, and the lens barrel is fixed to the base and holds the lens. It is made up of. In order to obtain a good image on the image sensor, the lens needs to be arranged at an accurate position in the optical axis direction with respect to the image sensor. For this reason, it is necessary to accurately position the lens in the optical axis direction in the lens barrel.

A contact surface serving as a reference surface is formed on the lens barrel, and the lens and the lens can be accurately positioned by contacting the peripheral surface of the lens with the contact surface. Further, when a plurality of members are accommodated in the lens barrel, for example, when a plurality of lenses are accommodated or when a diaphragm plate or a filter is accommodated in addition to the lens, the lens abutting against the abutting surface of the lens barrel is used. Positioning was performed sequentially by contacting the opposite surface and overlapping. Further, in order to fix the plurality of members, the end portion is fixed to the lens barrel with an adhesive. As such a camera module, there is one as disclosed in Patent Document 1, for example.
JP 2003-114308 A

  However, when a plurality of members are superposed in the lens barrel, stress may be generated between the members due to external force applied to the lens barrel or thermal stress due to temperature change. At this time, the stress is finally applied to the adhesive, but if this occurs repeatedly, fatigue failure may occur. In order to prevent this, measures such as increasing the amount of adhesive or increasing the number of bonding points can be considered, but since the degree of stress generation varies from individual to individual, it is possible to reliably prevent the adhesive from being destroyed. Was difficult.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a camera module capable of preventing fatigue breakage without applying an excessive burden to the adhesive for fixing the member in the lens barrel. And

In order to solve the above problems, a camera module according to the present invention is a camera module having a lens barrel that holds therein a lens group formed by superposing a plurality of lenses in the optical axis direction.
A plate-shaped aperture plate is sandwiched between the first lens and the second lens constituting the lens group, and one surface of the peripheral portion of the first lens is a surface of a lens barrel or another lens. Positioned in contact with each other, the other surface of the peripheral portion sandwiches the diaphragm plate, and the second lens has one surface of the peripheral portion sandwiching the diaphragm plate and is bonded to the lens barrel at the peripheral portion. Fixed by the agent,
Projections that sandwich the diaphragm plate are formed on one surface of the periphery of the first lens and the second lens, respectively, and the projection of the first lens and the projection of the second lens are formed on the diaphragm plate. It is configured to be formed at different positions in the plane direction.

  In the camera module according to the present invention, the protrusions of the first lens and the second lens are each formed in an annular shape along the circumferential direction of each lens, and are formed at different positions in the radial direction. It is configured as a feature.

  Furthermore, in the camera module according to the present invention, the lens barrel has an abutting surface on which one surface of a peripheral portion of the third lens constituting the lens group is abutted and positioned. The lens of the first lens is positioned with one surface of the peripheral portion in contact with the other surface of the peripheral portion of the third lens, and the diaphragm plate is positioned with contact with the protrusion of the first lens, The second lens is characterized in that the protrusion is positioned in contact with the diaphragm plate.

  Furthermore, the camera module according to the present invention is characterized in that the diaphragm plate is formed of a resin material.

  According to the camera module of the present invention, the first lens and the second lens have protrusions that sandwich the diaphragm plate on one surface thereof, and the first lens protrusion and the second lens. The projections of the diaphragm are formed at different positions in the planar direction of the diaphragm plate, so that when the stress is generated between the first lens and the second lens, the projection parts are located at different positions so that the diaphragm plate Can be bent and absorbed, and an excessive load can be prevented from being applied to the adhesive for fixing the second lens, so that fatigue failure can be prevented.

  According to the camera module of the present invention, the protrusions of the first lens and the second lens are each formed in an annular shape along the circumferential direction of each lens, and are formed at different positions in the radial direction. Thus, the diaphragm plate can be securely clamped and fixed by the protrusions, and the diaphragm plate can be reliably bent to absorb the stress.

  Furthermore, according to the camera module of the present invention, the lens barrel has an abutting surface in which one surface of the peripheral portion of the third lens abuts and is positioned, and the first lens One surface is positioned in contact with the other surface of the periphery of the third lens, the diaphragm plate is positioned in contact with the projection of the first lens, and the second lens is positioned in contact with the diaphragm. By abutting and positioning, each lens and the diaphragm plate can be reliably positioned in the optical axis direction.

  Furthermore, according to the camera module of the present invention, the diaphragm plate is formed of a resin material, so that the diaphragm plate can have an appropriate elasticity, and therefore, the projections can be surely bent. Stress can be absorbed.

  Embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 shows a cross-sectional view of the camera module in the present embodiment. As shown in this figure, the camera module according to the present embodiment has a housing 2 disposed on a substrate 1. The substrate 1 has an image sensor 5 disposed on the upper surface, and the housing 2 is fixed on the substrate 1. And a lens barrel 4 that holds a lens group 6 that is fixed to the base 3 and includes a plurality of lenses. Here, the lens group 6 includes three lenses, a first lens 30, a second lens 31, and a third lens 32.

  The substrate 1 is formed in a flat plate shape, and an image sensor 5 made of CMOS or CCD is placed on the upper surface thereof. Light from the imaging target captured via the lens of the lens group 6 is imaged on the imaging device 5, and the imaging device 5 converts the received light into an electrical signal and outputs it.

  The base 3 constituting the housing 2 is formed by molding a resin material, a base portion 10 serving as a fixing portion with respect to the substrate 1 is provided at the lower portion, and a substantially cylindrical storage for storing the lens barrel 4 at the upper portion. The portions 11 are formed respectively. A bottom surface portion 12 having an opening 12a is formed in the lower part of the inner periphery of the storage portion 11, and a filter 13 is placed on the upper surface so as to close the opening 12a. In addition, a screw portion 14 provided with a screw thread is formed on the inner peripheral surface of the storage portion 11.

  The lens barrel 4 constituting the housing 2 is formed by molding a resin material in the same manner as the base 3 and is formed in a cylindrical shape so that the lens group 6 can be held on the inner peripheral surface thereof. In the upper end portion, a flange portion 23 is formed over the entire circumference. The lens group 6 collects light from the imaging target, and in this embodiment, a convex lens and a concave lens are combined.

  On the outer peripheral surface of the lens barrel 4, a screw portion 24 provided with a screw thread is formed and can be screwed to the screw portion 14 of the storage portion 11. Accordingly, the lens barrel 4 is movable with respect to the storage portion 11 so that the lens barrel 4 can be adjusted in the optical axis direction of the lens group 6.

  The lens barrel 4 has an opening 20 formed on the imaging target side, and a first holding part 21 having a small opening diameter for holding the third lens 32 inside the imaging element side, and a first The second holding part 22 that holds the lens 30 and the second lens 31 and has an opening diameter larger than that of the first holding part 21 is formed continuously through the step part 23. Further, the first holding portion 21 is formed with a contact surface 21a serving as a reference surface for positioning the third lens 32 so as to face the imaging element side.

  In the lens group 6, the third lens 32 is disposed closest to the imaging target side, and the first lens 30 and the second lens 31 are sequentially disposed from the third lens 32 toward the imaging element side. The third lens 32 arranged closest to the imaging target side is formed as a lens part 32a having a central function as a lens, and a peripheral part 32b to be held by the lens barrel 4 is formed in the peripheral part. Is done. The peripheral portion 32b is formed to have an outer shape that substantially matches the inner diameter of the first holding portion 21, and the imaging target side surface is a planar outer periphery that contacts the contact surface 21a of the first holding portion 21. It is formed as a surface 32c. When the outer peripheral surface 32c is brought into contact with the contact surface 21a of the first holding portion 21, the third lens 32 is accurately positioned in the optical axis direction. A planar inner peripheral surface 32d is formed on the surface opposite to the peripheral portion 30b facing the outer peripheral surface 32c.

  The first lens 30 provided so as to overlap with the third lens 32 is formed as a lens portion 30a having a central portion functioning as a lens, and the periphery thereof is a periphery for being held by the lens barrel 4 Part 30b is formed. The peripheral portion 30b is formed so as to have an outer shape substantially matching the inner diameter of the second holding portion 22, and the imaging target side surface of the peripheral portion of the lens portion 30a is in contact with the inner peripheral surface 32d of the third lens 32. A planar outer peripheral surface 30c in contact therewith is formed. The outer peripheral surface 30c comes into contact with the inner peripheral surface 32d of the third lens 32 that is accurately positioned with respect to the lens barrel 4, so that the first lens 30 is accurately positioned in the optical axis direction. . A planar inner peripheral surface 30d is formed on the surface opposite to the peripheral portion 30b facing the outer peripheral surface 30c. Note that only the outer peripheral surface 30c is in contact with the imaging lens side surface of the first lens 30 toward the outside, and other portions are not in contact with the lens and the lens barrel 4. Accordingly, accurate positioning can be achieved by abutting the outer peripheral surface 30c against the inner peripheral surface 32d of the third lens 32.

  A diaphragm plate 33 is sandwiched between the first lens 30 and the second lens 31. The diaphragm plate 33 has an opening 33a having a predetermined diameter at the center, and adjusts the amount of light collected from the imaging target onto the imaging device 5. The diaphragm plate 33 is formed of a resin material and is formed to be a thin flat plate as a whole.

  A protrusion 30e protruding in the circumferential direction is formed on the inner peripheral surface 30d of the first lens 30, and the imaging target side surface of the diaphragm plate 33 is in contact with and held by the tip of the protrusion 30e. Yes. The second lens 31 is formed as a lens portion 31a having a central function as a lens, and a peripheral portion 31b to be held by the lens barrel 4 is formed in the peripheral portion, and an imaging target of the peripheral portion 30b An outer peripheral surface 31c facing the inner peripheral surface 30d of the first lens 30 is formed on the side surface. The outer peripheral surface 31c is also formed with a protruding portion 31e that protrudes in the circumferential direction, and the image sensor side surface of the diaphragm plate 33 is in contact with and held by the tip of the protruding portion 31e. That is, the diaphragm plate 33 is sandwiched and fixed on both sides by the protrusion 30e of the first lens 30 and the protrusion 31e of the second lens 31. The second lens 31 has a planar inner peripheral surface 31d on the surface opposite to the peripheral portion 31b facing the outer peripheral surface 31c. An adhesive 34 is provided on the peripheral edge portion of the inner peripheral surface 31 d and is fixedly bonded to the lens barrel 4.

  As described above, the third lens 32 is positioned in the optical axis direction by the outer peripheral surface 32 c abutting against the lens barrel 4, and the outer peripheral surface 30 c of the first lens 30 is the inner peripheral surface of the third lens 32. The second lens 31 is positioned in the optical axis direction by contacting the outer peripheral surface 31c with the inner peripheral surface 31d of the second lens 31. In addition, the lens group 6 is fixed in the optical axis direction by the second lens 31 being bonded and fixed to the lens barrel 4 by the adhesive 34.

  FIG. 2 shows a plan view of the first lens 30, the second lens 31 and the diaphragm plate 33. In this figure, each lens and the structure formed thereon are indicated by solid lines, and the diaphragm plate 33 is indicated by broken lines. As shown in this figure, the protrusion 30e formed on the first lens 30 and the protrusion 31e formed on the second lens 31 are both formed in an annular shape over the entire circumference in the circumferential direction of each lens. Is done. Further, the protrusion 30e of the first lens 30 is formed on the inner peripheral side with respect to the protrusion 31e of the second lens 31, and these protrusions 30e and 31e are formed at positions different from each other in the radial direction. In other words, the diaphragm plate 33 is sandwiched between the projection 30e of the first lens 30 and the projection 31e of the second lens 31 at different positions in the radial direction.

  FIG. 3 is a cross-sectional view of the vicinity of the first lens 30, the second lens 31, and the diaphragm plate 33, in which the protrusions 30e and 31e are exaggerated. As shown in FIG. 3A, the diaphragm plate 33 is held on the inner peripheral side by the protruding portion 30 e of the first lens 30 and on the outer peripheral side by the protruding portion 31 e of the second lens 31. FIG. 3B shows a case where stress is applied to each lens from this state. As shown in FIG. 3B, when stress is applied between the first lens 30 and the second lens 31, the diaphragm plate 33 causes the protrusion 30 e of the first lens 30 and the protrusion of the second lens 31. It is pressed from both sides by the part 31e. Here, the protrusion 30e of the first lens 30 and the protrusion 31e of the second lens 31 are formed at different positions in the radial direction, and the diaphragm plate 33 itself is formed of a resin material. By having elasticity, the diaphragm plate 33 can be bent in the optical axis direction of the lens. As a result, the stress is absorbed, and the stress applied to the adhesive 34 that fixes the second lens 31 can be reduced.

  Although the embodiment of the present invention has been described above, the application of the present invention is not limited to this embodiment, and can be applied in various ways within the scope of its technical idea. For example, in the present embodiment, the protrusion 30e of the first lens 30 and the protrusion 31e of the second lens 31 are each formed in an annular shape over the entire circumference, but are not necessarily formed over the entire circumference. However, the protrusions 30e and 31e may be provided on a part of the circumference, or a plurality of protrusions 30e and 31e may be formed to be provided in the circumferential direction. However, the diaphragm plate 33 can be stably held by providing the protrusions 30e and 31e all around the circumference.

  In the present embodiment, the protrusion 30e of the first lens 30 and the protrusion 31e of the second lens 31 are formed so as to be different from each other in the radial direction, but are different from each other in the circumferential direction. You may form as follows. In any case, the protrusion 30e of the first lens 30 and the protrusion 31e of the second lens 31 are formed at different positions in the planar direction of the diaphragm plate 33, so that the first lens 30 and the second lens 31 When a stress is applied between the lenses 31, the diaphragm plate 33 can be bent so that a large stress is not applied to the fixing portion by the adhesive 34.

  Furthermore, in this embodiment, the lens group 6 is composed of three lenses from the first lens 30 to the third lens 32. However, the number and configuration of the lenses are not limited to this, and two or more lenses are used. What is necessary is just to be comprised by this, Comprising: The aperture_diaphragm | restriction board 33 is pinched | interposed between them.

It is sectional drawing of the camera module in this embodiment. It is a top view of a 1st lens, a 2nd lens, and an aperture plate. It is sectional drawing of the 1st lens, the 2nd lens, and diaphragm aperture vicinity, Comprising: It is the figure which exaggerated and showed the projection part.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Board | substrate 2 Housing | casing 3 Base part 4 Lens tube 5 Image pick-up element 6 Lens group 10 Base part 11 Storage part 12 Bottom part 13 Filter 14 Screw part 20 Opening part 21 First holding part 21a Contact surface 22 Second holding part 23 Step part 24 Screw part 30 First lens 30e Projection part 31 Second lens 31e Projection part 32 Third lens 33 Diaphragm plate 34 Adhesive

Claims (4)

In a camera module having a lens barrel that internally holds a lens group formed by superposing a plurality of lenses in the optical axis direction,
A plate-shaped stop plate is sandwiched between the first lens and the second lens constituting the lens group, and one surface of the peripheral portion of the first lens is a surface of a lens barrel or another lens. Positioned in contact with each other, the other surface of the peripheral portion sandwiches the diaphragm plate, and the second lens has one surface of the peripheral portion sandwiching the diaphragm plate and is bonded to the lens barrel at the peripheral portion. Fixed by the agent,
Projections that sandwich the diaphragm plate are formed on one surface of the periphery of the first lens and the second lens, respectively, and the projection of the first lens and the projection of the second lens are formed on the diaphragm plate. A camera module formed at different positions in a planar direction.   The protrusions of the first lens and the second lens are respectively formed in an annular shape along the circumferential direction of each lens, and are formed at different positions in the radial direction. The camera module.   The lens barrel has an abutting surface in which one surface of a peripheral portion of a third lens constituting the lens group is abutted and positioned, and the first lens has one surface of the peripheral portion. The diaphragm is positioned in contact with the other surface of the peripheral portion of the third lens, the diaphragm plate is positioned in contact with the protrusion of the first lens, and the protrusion of the second lens is positioned in the diaphragm plate. The camera module according to claim 1, wherein the camera module is positioned in contact with the camera module.   The camera module according to claim 1, wherein the diaphragm plate is formed of a resin material.

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