JP2010139622A - Driving device and imaging apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a technology that reduces possibility that each elastic member supporting a lens may be, for example, damaged by movement of a driven body due to external force. <P>SOLUTION: A camera module 500A includes: a lens layer 16 formed in a wafer level; an imaging section disposed on one main side of the lens layer 16; a cover 20 disposed on the other main side of the lens layer 16; a first parallel spring elastically connecting the lens layer 16 and the imaging section; a second parallel spring elastically connecting the lens layer 16 and the cover 20; and a driving layer for driving the driven body including the lens layer 16, first parallel spring, and second parallel spring. The cover 20 accommodates the driven body. When an external force is applied to the driven body, the driven body comes into contact with the internal wall NK of the cover 20. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a driving technique for driving a lens.

  2. Description of the Related Art In recent years, small electronic devices (for example, mobile phones) to which a photographing function is added by mounting a micro camera unit (MCU) are rapidly spreading. Accordingly, further miniaturization of the camera module used as the MCU is desired.

  In a conventional camera module, a lens barrel and a lens holder that support a lens, a holder that supports an infrared (IR) cut filter, a substrate, and a casing that holds a laminate including an imaging element and an optical element, such a stack Resins that seal the body are required. For this reason, it has been difficult to produce a camera module by miniaturizing a large number of components and combining the components with high accuracy.

  With respect to such a problem, in Patent Document 1, a laminated member in which a substrate, a semiconductor sheet on which a large number of imaging elements are formed, and a lens array sheet on which a large number of imaging lenses are formed are attached via a resin layer. A technique for forming individual camera modules by dicing the laminated member is proposed.

JP 2007-12995 A

  However, in the technique described in Patent Document 1, since each functional layer such as a layer including an image sensor and a layer including a lens is formed in a wafer state (at the wafer level), the camera module is formed. In this case, a driving space for driving the lens for autofocus or zooming is not secured, and the lens cannot be driven.

  Therefore, for example, a layer including an elastic member that can be elastically deformed in the optical axis direction of the lens is interposed between the lens and the upper and lower layers that sandwich the lens, and the upper and lower layers that sandwich the lens and the lens with each elastic member. It is conceivable that each lens is connected and one lens layer is separated from the other layer sandwiching the lens to secure the lens driving space and drive the lens.

  However, if the lens drive space is secured and the lens can be moved as a driven body, when an impact is applied to the camera module due to a collision caused by dropping or the like, the lens moves in the drive space. There is a high possibility that each elastic member to be supported is damaged.

  Therefore, an object of the present invention is to provide a technique capable of reducing the possibility that each elastic member supporting a lens is damaged by the movement of a driven body by an external force.

  In order to solve the above-described problem, the invention of claim 1 is an imaging apparatus, wherein a lens unit manufactured at a wafer level, a first fixing unit disposed on one main surface side of the lens unit, and the A second fixing part disposed on the other main surface side of the lens part; a first elastic member that elastically connects the lens part and the first fixing part; and the lens part and the second fixing part. A second elastic member that is elastically connected; and a driving layer that drives a driven body including the lens unit, the first elastic member, and the second elastic member. A housing that houses a driving body, and the driven body hits an inner wall of the housing when an external force is applied to the driven body.

  The invention of claim 2 is the imaging device according to claim 1, wherein, in a cross section of the lens unit in a plane perpendicular to the optical axis of the lens unit, the longest distance from the optical axis to the outer edge of the cross section. Is longer than the shortest distance from the optical axis in the plane to the inner wall of the housing.

  According to a third aspect of the present invention, in the imaging apparatus according to the first or second aspect of the present invention, the lens unit is composed of one or more layers having lenses.

  According to a fourth aspect of the present invention, there is provided an imaging apparatus comprising: a lens manufactured at a wafer level; a first fixed portion disposed on one principal surface side of the lens portion; and the other principal surface side of the lens portion. A second fixing part disposed on the first elastic member, a first elastic member elastically connecting the lens part and the first fixing part, and a second elastically connecting the lens part and the second fixing part. An elastic member; and a driving layer that drives a driven body including the lens portion, the first elastic member, and the second elastic member, and the second fixing portion is a housing that houses the driven body. And the cross-sectional shape of the lens portion in a plane perpendicular to the optical axis of the lens portion is a rectangle, and the longest distance from the center of the rectangular cross section to the outer edge of the rectangular cross section is from the center of the rectangular cross section to the housing. Longer than the shortest distance to the inner wall.

  Further, the invention of claim 5 is an imaging apparatus, wherein a lens unit manufactured at a wafer level, a first fixing unit disposed on one main surface side of the lens unit, and the other main surface of the lens unit. A second fixing portion disposed on the side, a first elastic member that elastically connects the lens portion and the first fixing portion, and a first elastic member that elastically connects the lens portion and the second fixing portion. A second elastic member; and a driving layer that drives a driven body including the lens portion, the first elastic member, and the second elastic member, and the second fixing portion is a housing that houses the driven body. The cross-sectional shape of the lens portion in a plane perpendicular to the optical axis of the lens portion is a polygon having a circumscribed circle, and the radius of the circumscribed circle is from the outer center of the circumscribed circle to the inner wall of the housing. Longer than the shortest distance.

  Further, the invention of claim 6 is a driving device, which is a lens unit manufactured at a wafer level, a first fixing unit disposed on one main surface side of the lens unit, and the other main surface of the lens unit. A second fixing portion disposed on the side, a first elastic member that elastically connects the lens portion and the first fixing portion, and a first elastic member that elastically connects the lens portion and the second fixing portion. A second elastic member; and a driving layer that drives a driven body including the lens portion, the first elastic member, and the second elastic member, and the second fixing portion is a housing that houses the driven body. The driven body hits the inner wall of the housing when an external force is applied to the driven body.

  According to the first to sixth aspects of the present invention, since the movement of the driven body due to an external force can be suppressed, the influence of the external force on each elastic member that supports the lens can be reduced.

  Embodiments of the present invention will be described below with reference to the drawings.

<Embodiment>
FIG. 1 is a schematic diagram showing a schematic configuration of a mobile phone 100 equipped with a camera module 500A according to an embodiment of the present invention. In FIG. 1 and the drawings after FIG. 1, three axes XYZ orthogonal to each other are appropriately attached in order to clarify the orientation relationship.

  As shown in FIG. 1, the mobile phone 100 is configured as a foldable mobile phone, and includes a first housing 200, a second housing 300, and a hinge part 400.

  Each of the first casing 200 and the second casing 300 is a plate-shaped rectangular parallelepiped, and has a role as a casing for storing various electronic members. Specifically, the first casing 200 includes a camera module 500A and a display (not shown), and the second casing 300 includes a control unit that electrically controls the mobile phone 100, buttons, and the like. An operation member (not shown) is provided.

  The hinge part 400 connects the first casing 200 and the second casing 300 so as to be rotatable. Thereby, the mobile phone 100 can be folded.

  FIG. 2 is a schematic cross-sectional view of the mobile phone 100 focusing on the first housing 200.

  As shown in FIG. 2, the camera module 500A has a small imaging device having a XY cross section of about 5 mm square and a thickness (depth in the Z direction) of about 3 mm, a so-called micro camera unit (MCU). It is configured as.

  Hereinafter, the configuration of the camera module 500A, the manufacturing process thereof, and the like will be sequentially described.

<Configuration of camera module>
FIG. 3 is a schematic cross-sectional view of the camera module 500A, and the direction indicated by the arrow YJ1 is the + Z direction.

  As shown in FIG. 3, the camera module 500 </ b> A includes a drive mechanism KB that drives a lens layer (also referred to as a “lens unit”) 16 as an imaging optical system, and an imaging unit PB that acquires a captured image related to a subject image. The drive mechanism KB and the imaging unit PB are connected via a spacer SA.

  The imaging unit PB has a configuration in which, for example, an imaging element layer 11 having an imaging element 111 such as a COMS sensor or a CCD sensor, an imaging element holder layer 12, and an infrared (IR) cut filter layer 13 are stacked in this order. Have.

  In the space covered with the imaging unit PB and the cover 20, both are manufactured in a wafer state (at the wafer level), the lens layer 16, the first parallel spring (lower layer parallel spring) 15 that holds the lens layer 16, and A second parallel spring (upper layer parallel spring) 17 and an actuator layer (drive layer) 14 functioning as a drive unit are stored. The functional layers stored in the space constitute a drive mechanism KB that drives the lens layer 16 in cooperation with each other.

  Specifically, in the camera module 500 </ b> A, the cover 20 and the imaging unit PB are fixing units for the lens layer 16.

  The lens layer 16 is supported by a first parallel spring 15 and a second parallel spring 17 coupled to the fixed portion. More specifically, a first parallel spring 15 is interposed between the imaging unit PB and the lens layer 16 on one main surface side (−Z side) of the lens layer 16, and the other main surface side of the lens layer 16. A second parallel spring 17 is interposed between the cover 20 and the lens layer 16 on the (+ Z side).

  In a non-driving state (for example, a stationary state before driving), the first parallel spring 15 and the second parallel spring 17 are in an elastically deformed state, and the elastic force of the first parallel spring 15 and the elastic force of the second parallel spring 17 are obtained. The lens layer 16 is stationary at a position where the two are balanced.

  The actuator layer 14 has a displacement generating portion that generates a drive displacement in a direction (+ Z direction) from the one main surface side to the other main surface side of the lens layer 16, and is disposed on the one main surface side of the lens layer 16. . The displacement generating unit comes into contact with the protruding portion 161 protruding toward the one main surface side of the lens layer 16, and the drive displacement generated in the displacement generating portion is transmitted to the lens layer 16 through the protruding portion 161.

  As described above, in the camera module 500A, the lens layer 16 is coupled to the elastic members disposed at positions facing each other via the lens layer 16, and the elastic member is in a direction perpendicular to the lens layer 16 (lens The lens layer 16 is held in a state of being elastically deformed in the vertical direction of the layer 16. In this state, when a driving force is transmitted from the displacement generating portion of the actuator layer 14 to the lens layer 16, the lens layer 16 and each elastic member are displaced as driven bodies.

  As described above, the driving mechanism KB provided in the camera module 500A can displace the lens layer 16 manufactured at the wafer level in the optical axis direction of the lens layer 16, and causes the camera module 500A to function as a driving device.

<About each functional layer>
Below, the detail of each functional layer which comprises camera module 500A is demonstrated. In each functional layer, a surface on the −Z direction side is referred to as a surface on one main surface side, and a surface on the + Z direction side is referred to as a surface on the other main surface side.

○ Image sensor layer 11:
As shown in FIG. 3, the image sensor layer 11 includes an image sensor 111 that receives subject light that has passed through the photographing optical system and generates an image signal related to the subject image, its peripheral circuit, and an outer periphery that surrounds the image sensor 111. It is a member provided with a part.

  Note that a solder ball HB for performing reflow soldering is provided on one main surface (the surface on the −Z side) of the imaging element layer 11. Although not shown here, a wiring for applying a signal to the image sensor 111 and reading a signal from the image sensor 111 is connected to one main surface of the image sensor layer 11. Various terminals are provided.

○ Image sensor holder layer 12:
The imaging element holder layer 12 is a member that holds the imaging element layer 11 that is formed of, for example, a material such as a resin and is joined by an adhesive or the like. An opening is provided substantially at the center of the image sensor holder layer 12.

○ Infrared cut filter layer 13:
The infrared cut filter layer 13 is formed by multilayering transparent thin films having different refractive indexes on a transparent substrate.

  Specifically, the infrared cut filter layer 13 is formed by, for example, sputtering a large number of transparent thin films having different refractive indexes on the upper surface of a substrate made of glass or transparent resin, and the thickness and refractive index of the thin film. In combination, the wavelength band of the transmitted light is limited. As the infrared cut filter layer 13, for example, a layer that blocks light in a wavelength band of 600 nm or more is employed.

○ Lens layer 16:
The lens layer 16 is manufactured at a wafer level using a glass substrate as a base material, and is formed by superposing one or more layers (also referred to as “lens constituent layers”) having lenses. In this embodiment, the case where the lens layer 16 is configured by superimposing three lenses is illustrated. FIG. 4 is a schematic cross-sectional view of the lens layer 16, and the direction indicated by the arrow YJ2 is the + Z direction. FIG. 5 is an external view of the lower surface of the lens layer 16.

  As shown in FIG. 4, the lens layer 16 includes a lens constituent layer LY1 having the first lens G1, a lens constituent layer LY2 having the second lens G2, and a lens constituent layer LY3 having the third lens G3. The lens constituent layers LY1 to LY3 are coupled via the ribs RB in this order.

  As shown in FIGS. 4 and 5, a protrusion 161 is provided on one main surface of the lens constituent layer LY1 having the first lens G1 in a non-lens portion that does not function as a lens.

  Each of the lens constituent layers LY1 to LY3 is produced by the same method using the glass substrate 162 as a base material. FIG. 6 is a diagram showing how the lens constituent layer LY3 having the third lens G3 is produced.

  Specifically, as shown in FIG. 6, a highly transparent acrylic or epoxy ultraviolet (UV) curable resin is applied to both surfaces of the glass substrate 162. Then, a transparent lens molding die 163 having the shape of each lens (in FIG. 6, the third lens G3) is pressed from both sides with a predetermined pressure and irradiated with ultraviolet rays UV1 to each surface of the glass substrate 162. The polymer lenses GP1 and GP2 are respectively molded.

  In each of the lens constituent layers LY1 to LY3 thus manufactured, alignment marks for alignment are formed at two or more predetermined positions. The lens constituent layers LY1 to LY3 are assembled into an integrated lens layer 16 with a rib layer having a rib RB sandwiched between the lens constituent layers LY1 to LY3.

  Specifically, the lens constituent layers LY1 to LY3 and the rib layer are aligned and bonded in the shape of the substrate while confirming the respective alignment marks using a mask aligner or the like. As a bonding method, a UV cured layer is provided on the surface of the rib layer to be bonded to each of the lens constituent layers LY1 to LY3, and a method of bonding by irradiating ultraviolet rays, or irradiation of an inert gas plasma on the surface of the rib layer is performed. Then, a technique (surface activated bonding method) is employed in which the surfaces of the rib layers are bonded together while being activated.

  When forming a diaphragm on the camera module 500A, a method of forming a light shielding material thin film after applying a shadow mask to the layer having the second lens G2, or a resin material that is colored black is used. A configuration method or the like is used.

○ First parallel spring 15:
FIG. 7 is a top external view of the first parallel spring 15. FIG. 8 is a view showing the first parallel spring 15 attached to the lens layer 16.

  As shown in FIG. 7, the first parallel spring 15 is an elastic member having a fixed frame 151 and an elastic portion 152, and becomes a layer (elastic layer) that forms a spring mechanism in the camera module 500A.

  The fixed frame 151 constitutes the outer periphery of the first parallel spring 15 and is joined to an adjacent actuator layer 14 (specifically, a frame 142 (described later) of the actuator layer 14).

  The elastic part 152 is composed of an elastically deformable plate member EB, and is connected to the fixed frame 151 at a connection part PG1 of the plate member EB. The elastic portion 152 is joined to the lens layer 16 at the joint portion PG2 of the plate-like member EB. That is, the first parallel spring 15 is joined to the actuator layer 14 in the fixed frame 151, and is joined to the lens layer 16 in the joint part PG <b> 2 provided in the elastic part 152.

  When the lens layer 16 is moved in the + Z direction and the lens layer 16 and the actuator layer 14 are separated from each other, the connection portion PG1 and the joint portion PG2 are displaced in the Z direction, and the connection portion PG1 and the joint portion are separated. The plate-like member EB that connects PG2 is bent by bending deformation (bending deformation). As described above, the first parallel spring 15 functions as a spring mechanism in which the plate member EB is elastically deformed in a state where the lens layer 16 and the actuator layer 14 are separated from each other.

  The first parallel spring 15 is manufactured using a SUS metal material or phosphor bronze. For example, when the first parallel spring 15 is made of a SUS-based metal material, the shape of the parallel spring is patterned on the metal material by photolithography, and is immersed in an iron chloride-based etchant to perform wet etching. A pattern of parallel springs is formed.

○ Actuator layer 14:
The actuator layer 14 is a thin plate-like member in which a displacement element (also referred to as “actuator element”) 143 for generating a driving force is provided on a metal or silicon (Si) substrate. FIG. 9 is a top view of the actuator layer 14, and FIG. 10 is a side view of the actuator layer.

  Specifically, as shown in FIG. 9, the actuator layer 14 includes a frame 142 constituting the outer peripheral portion and two sheets extended from the frame 142 with respect to a hollow portion inside the frame 142. And a plate-like beam portion 141. A thin film-like actuator element 143 is provided on the other main surface side of the beam portion 141, and the beam portion 141 and the actuator element 143 have a relationship in which the other follows and deforms according to the deformation of one of them. It has become. For example, when the beam portion 141 functions as a thin film actuator, the beam portion 141 is deformed according to the deformation of the actuator element 143.

As the actuator element 143, for example, a member containing a shape memory alloy (SMA) is used. In this case, after an insulating layer such as SiO ₂ , a metal heater layer, and an SMA layer are formed on the substrate by using a sputtering method or the like, the beam portion 141 is set in a mold having a shape to be memorized, and a predetermined temperature (eg , 600 ° C.) heating (shape memory processing) is performed.

  The SMA has a characteristic that when it reaches a predetermined temperature by heating or the like, it is restored to a predetermined contracted shape (also referred to as “memory shape”) stored in advance. For this reason, when the SMA is heated by energizing the heater layer, the SMA contracts and deforms into a memorized shape, and the free end (extended end) FT of the beam portion 141 moves in the + Z direction (see FIG. 10). That is, the free end FT side of the beam portion 141 functions as a displacement generating portion.

  The heater layer is energized by the wiring 144 (broken line in FIG. 9) connected to the electrode of the imaging element layer 11. The conduction from the electrode to the heater layer is performed by the actuator layer 14 and the infrared cut. What is necessary is just to carry out through the thin conductive member (not shown) affixed on the side surface of the filter layer 13 and the image pick-up element holder layer 12.

  Further, the actuator element 143 may be constituted by an insulating layer and an SMA layer, and the SMA may be directly energized. In this case, the SMA is self-heated by the Joule heat generated by energizing the SMA, and is deformed into a predetermined contracted shape.

  The frame 142 of the actuator layer 14 is joined to the fixed frame 151 (see FIG. 8) of the first parallel spring 15. In the joined state, each beam portion 141 comes into contact with the projection 161 on the free end FT side, and the displacement generated at the free end FT of each beam portion 141 passes through each projection 161 to the lens layer 16. To be told. Thus, the beam portion 141 functions as an action portion that transmits displacement to the lens layer 16.

  Note that the amount of displacement generated on the free end FT side of the beam portion 141 differs depending on the heating temperature of the SMA, and the amount of displacement can be adjusted by controlling the amount of current supplied to the heater layer.

  In addition, the heater layer is also deformed with the deformation of the SMA, but the electric resistance value of the heater layer is also changed according to the deformation of the heater layer. For this reason, the amount of displacement may be controlled by monitoring the current resistance value of the heater layer with a driver IC provided to drive the actuator element 143.

○ Second parallel spring 17:
As shown in FIG. 7, the second parallel spring 17 is an elastic member having the same configuration and function as the first parallel spring 15, and includes a fixed frame body 171 and an elastic portion 172.

  The fixed frame body 171 of the second parallel spring 17 is joined to the cover 20, and the joint part PG <b> 2 provided on the elastic part 172 is joined to the other main surface of the lens layer 16.

  In this state, when the lens layer 16 and the cover 20 are pulled apart, elastic deformation occurs in the plate-like member EB, and the second parallel spring 17 functions as a spring mechanism.

○ Cover 20
The cover 20 is formed by press working using a mold using a resin material as a raw material. The cover 20 functions as a housing that houses and protects the first parallel spring 15, the second parallel spring 17, and the lens layer 16 as driven bodies, and serves as a fixing portion for the driven body.

  In addition, the cover 20 is diced for each camera module 500 </ b> A after being formed in a large number of lattice shapes by pressing a resin material.

<Relationship Between Lens Layer 16 and Cover 20>
In the camera module 500A, the lens layer 16 and the inner wall of the cover 20 functioning as a housing are usually spatially separated and in contact with each other. However, when the lens layer 16 moves due to the influence of external force, The layer 16 is configured to hit (collision) the inner wall of the cover 20.

  According to this, for example, even when an unexpected impact is given to the camera module 500A, the influence of the external force due to the impact on the first parallel spring 15 and the second parallel spring 17 that support the lens layer 16 is reduced. Can do.

  Specifically, this will be described with reference to FIGS. 11, 13, and 14 are cross-sectional views of the camera module 500 </ b> A on a plane parallel to the stacking direction of the lens layer 16. FIG. 12 is a diagram illustrating how the lens layer 16 moves due to external force.

  As shown in FIG. 11, in this embodiment, the cross-sectional shape of the lens layer 16 in a plane perpendicular to the stacking direction of the lens layer 16 (also simply expressed as “parallel to the lens layer 16”) is a rectangle including a square. Shape. The inner wall NK of the cover 20 on a plane parallel to the lens layer 16 is also formed in a rectangular shape. Then, when an external force acts on the driven body including the first parallel spring 15, the second parallel spring 17, and the lens layer 16 and the driven body moves, the driven body (here, the lens layer 16) is moved to the cover 20. It is comprised so that it may contact with inner wall NK.

  For example, as shown in FIG. 12, when the lens layer 16 rotates in the direction indicated by the arrow YA under the influence of external force, each corner KP <b> 1 to KP <b> 4 of the lens layer 16 comes into contact with the inner wall NK of the cover 20. Thus, when the lens layer 16 comes into contact with the inner wall NK of the cover 20 that functions as a fixed portion, the movement of the driven body due to the external force is limited (suppressed), so that the external force is applied to each elastic member that supports the lens layer 16. The influence given can be reduced. According to this, it is possible to prevent the first parallel spring 15 and the second parallel spring 17 holding the lens layer 16 from being plastically deformed or damaged by the movement of the lens layer 16 due to an external force.

  In order to bring the lens layer 16 into contact with the inner wall NK of the cover 20 when the lens layer 16 is moved by an external force, the lens layer 16 and the cover 20 are configured to have the following relationship.

  Specifically, as shown in FIG. 13, a rectangular cross section ML1 is formed from the center (center point) CP of the cross section (also referred to as “rectangular cross section”) ML1 of the lens layer 16 in a plane perpendicular to the stacking direction of the lens layers 16. The longest distance to the outer edge GF1 to be defined (distance represented by a double arrow LD1 in FIG. 13) is the shortest distance from the center CP of the rectangular cross section ML1 to the inner wall NK of the cover 20 (represented by the double arrow SD1 in FIG. 13). The lens layer 16 and the cover 20 are configured to be longer than (distance).

  Note that the center point CP of the cross section ML1 of the lens layer 16 is also expressed as a symmetric point that is point-symmetric with respect to the figure indicated by the cross section ML1.

  Further, the relationship between the lens layer 16 and the cover 20 can be expressed by using the optical axis LJ1 of the lens instead of the center CP of the rectangular cross section ML1. That is, the lens layer 16 and the cover 20 have a longest distance (double arrow LD1) from the optical axis LJ1 to the outer edge GF1 of the cross section in the cross section of the lens layer 16 in a plane perpendicular to the optical axis LJ1 of the lens layer 16. It is configured to be longer than the shortest distance (double arrow SD1) from the optical axis LJ1 on the plane to the inner wall NK of the cover 20. In FIG. 13, the position of the optical axis LJ1 in the rectangular cross section ML1 coincides with the center CP of the rectangular cross section ML1.

  In addition, the relationship between the lens layer 16 and the cover 20 is such that a circumscribed circle EG1 (passing through each vertex TP1 to TP4 of the cross section ML1 in the cross section ML1 of the lens layer 16 in a plane perpendicular to the stacking direction of the lens layers 16 ( (See FIG. 14).

  That is, when the cross-sectional shape of the lens layer 16 is a polygon having a circumscribed circle EG1, the radius ED1 of the circumscribed circle EG1 is the shortest distance from the outer center LP1 of the circumscribed circle EG1 to the inner wall NK of the cover 20 (FIG. 14). The lens layer 16 and the cover 20 are configured to be longer than the distance represented by the double arrow SD1.

<Manufacturing process of camera module 500A>
Here, the manufacturing process of the camera module 500A will be described in detail.

  FIG. 15 is a flowchart showing a manufacturing process of the camera module 500A. As shown in FIG. 15, (Process A) Sheet preparation (Step SP1), (Process B) Sheet joining (Step SP2), (Process C) Dicing (Step SP3), (Process D) Attachment of cover 20 ( Step SP4) and (Step E) securing the drive space (Step SP5) are sequentially performed, and the camera module 500A is manufactured. Hereinafter, each step will be described.

○ Preparation of sheet (process A):
First, in step SP1, a sheet relating to each functional layer forming the camera module 500A is formed for each layer. FIG. 16 is a plan view illustrating a configuration example of a sheet to be prepared. Here, it is assumed that a disk-shaped sheet is prepared.

  In the sheet for each functional layer, a large number of chips corresponding to members related to the functional layer are formed in a matrix in a predetermined arrangement.

  For example, as shown in FIG. 16, a large number of chips corresponding to the image sensor holder layer 12 are formed in a predetermined arrangement on the sheet (image sensor holder sheet) HU2 of the image sensor holder layer 12. Here, the expression “predetermined arrangement” is used to include a state in which a large number of chips are arranged at predetermined intervals in a predetermined direction.

  The imaging element holder sheet HU2 is manufactured by, for example, press working using a metal mold using a resin material as a raw material.

  As described above, in step SP1, each of the imaging element layer 11, the infrared cut filter layer 13, the actuator layer 14, the first parallel spring 15, the lens layer 16, and the second parallel spring 17 is the same as in the imaging element holder sheet HU2. Each of the sheets HU1, HU3 to HU7 including chips related to the functional layer is prepared.

○ Sheet joining (process B):
In step SP2, the sheets HU1 to HU7 are joined to each other. FIG. 17 is a diagram schematically illustrating a state in which the prepared sheets HU1 to HU7 are sequentially stacked and joined.

  Specifically, as shown in FIG. 17, the imaging element sheet HU1, the imaging element holder sheet HU2, the infrared cut filter sheet HU3, the actuator sheet HU4, the first parallel spring sheet HU5, the lens sheet HU6, and the second parallel. The spring sheet HU7 is aligned (aligned) with the sheet shape so that the chips included in the sheets HU1 to HU7 are stacked on each other. And each sheet | seat HU1-HU7 is joined using an adhesive agent etc.

○ Dicing (Process C):
In the next step SP3, the laminated member formed by laminating the seven sheets HU1 to HU7 is protected by a dicing tape or the like and then separated for each chip by a dicing apparatus. Thus, a large number of optical system units (optical units) 50 having seven layers 11 to 17 stacked as shown in FIG. 18 are generated.

  In the optical unit 50 immediately after the cover 20 is attached, the lens layer 16 cannot be driven because the drive space for the lens layer 16 is not yet secured. Further, in the optical unit 50 immediately after the cover 20 is attached, the beam portion 141 of the actuator layer 14 is pushed in the −Z direction by the protrusion 161 on the free end FT side of the beam portion 141 and is in a curved state.

○ Attaching the cover 20 (process D):
In step SP4, the cover 20 is attached to the optical unit 50. FIG. 19 is a diagram showing the optical unit 50 to which the cover 20 is attached.

  Specifically, as shown in FIG. 19, the optical unit 50 is installed on the assembly jig JG1. Then, the cover 20 is put on the optical unit 50, and the fixed frame body 171 of the second parallel spring 17 and the cover 20 are joined by an adhesive or the like.

  The inclination of the installation surface of the assembly jig JG1 is preferably within 5 minutes (1/12 degrees) with respect to the horizontal plane.

○ Secure drive space (Process E):
In step SP5, the drive space of the driven body (lens layer 16) is secured. FIG. 20 is a diagram for explaining a process of securing a driving space for the lens layer 16.

  Specifically, as shown in FIG. 20, a cover push-up jig JG <b> 2 is installed on the upper part of the cover 20. The cover lifting jig JG2 has a vacuum chuck portion JG3 capable of holding the cover 20. Further, the cover push-up jig JG2 has a submicron push-up accuracy by a combination of an AC servo motor and a piezo actuator. Using this mechanism, the cover 20 is pulled up in the + Z direction as indicated by the arrow YJ3.

  In the present embodiment, the cover 20 is pulled up by a predetermined amount (for example, 200 μm) according to the driving amount of the lens layer 16.

  Then, the UV curable resin KJ1 is inserted into the gap KG between the lower portion of the raised cover 20 and the optical unit 50 (see FIG. 3), and the UV curable resin KJ1 is cured by irradiation with ultraviolet rays. By the curing of the UV curable resin KJ1, the cover 20 and the imaging unit PB are relatively fixed.

  When the cover 20 is fixed, the inclination of the cover 20 is suppressed by monitoring the distance that the cover 20 is pulled up and the change in the inclination of the cover 20.

  As the cover 20 is lifted, the cover 20 and the imaging unit PB are separated in the vertical direction of the lens layer 16, and the first parallel spring 15 and the second parallel spring 17 are elastically deformed. Then, the lens layer 16 is movable in the Z direction.

  Thus, in step SP5, the attached cover 20 is pulled up in the + Z direction, and the drive space of the lens layer 16 is ensured.

  Further, the bending deformation (see FIG. 19) in the beam portion 141 of the actuator layer 14 that has been pushed and bent in the −Z direction by the protruding portion 161 is alleviated by pulling up the cover 20 (see FIG. 20).

  In a state where the cover 20 is fixed by the UV curable resin KJ1 (see FIG. 3), the beam portion 141 preferably has a slight bending deformation due to the bending in the −Z direction by the protrusion 161. In other words, in a state where the cover 20 is fixed, the beam portion 141 is preferably in contact with (in contact with) the protrusion 161.

  When the lens layer 16 is driven by a focusing operation or the like, the beam portion 141 of the actuator layer 14 pushes up the projection 161 in the + Z direction. For example, the beam 141 and the projection in a stationary state before driving. In the case where the distance between the beam 161 and the protruding portion 161 is required, a predetermined time is required. That is, when the beam portion 141 and the projection portion 161 are separated in a stationary state, an idle swing section exists during driving.

  However, when the beam part 141 and the protrusion 161 are in contact with each other in a state where the cover 20 is fixed, that is, in a stationary state before driving, since there is no idle swing section, the driving displacement generated in the beam part 141 is not detected. It can be transmitted to the protrusion 161 without waste.

  Thus, the protrusion 161 plays a role of efficiently transmitting the driving displacement generated in the beam 141 to the lens layer 16 that is a driven body.

<Modification>
Although the embodiments of the present invention have been described above, the present invention is not limited to the contents described above.

  For example, in the above embodiment, the cross-sectional shape of the lens layer 16 in a plane perpendicular to the stacking direction of the lens layers 16 is a rectangular shape, but is not limited thereto. 21 to 24 are cross-sectional views in a plane parallel to the stacking direction of the lens layer 16 according to the modification.

  Specifically, the cross-sectional shape of the lens layer 16 in a plane perpendicular to the stacking direction of the lens layers 16 may be a pentagon as shown in FIG. 21 or a hexagon as shown in FIG.

  For example, as shown in FIG. 21, when the cross-sectional shape of the lens layer 16B is a pentagon, the cross-section ML2 from the optical axis LJ2 in the cross-section ML2 of the lens layer 16B in a plane perpendicular to the optical axis LJ2 of the lens layer 16B. The lens layer 16B and the cover 20B so that the longest distance to the outer edge GF2 (double arrow LD2) is longer than the shortest distance (double arrow SD2) from the optical axis LJ2 to the inner wall of the cover 20 in a plane perpendicular to the optical axis LJ2. Is composed.

  Further, as shown in FIG. 22, when the cross-sectional shape of the lens layer 16C is a regular hexagon, the cross-sectional shape of the lens layer 16C has a circumscribed circle EG3, and the radius ED3 of the circumscribed circle EG3 is equal to the circumscribed circle EG3. The lens layer 16C and the cover 20C are configured to be longer than the shortest distance from the outer center LP3 to the inner wall of the cover 20C (a distance represented by a double arrow SD3 in FIG. 22).

  The shape of the internal space of the cover 20 may be changed according to the lens layers 16B and 16C accommodated as shown in FIGS.

  Further, the cross section of the lens layer 16 in a plane perpendicular to the stacking direction of the lens layers 16 has a shape in which the rectangular four corners FS1 to FS4 are missing, as in the lens layer 16D in FIG. 23, or the lens layer 16E in FIG. In addition, the shape may include a protrusion VP for preventing rotation.

  In the above embodiment, when an impact is applied to the camera module 500A, the lens layer 16 of the driven body hits the inner wall NK of the cover 20, but the first parallel spring 15 and the first parallel spring 15 included in the driven body A configuration in which at least one of the two parallel springs 17 hits the inner wall NK of the cover 20 may be adopted.

  In the above embodiment, the conductive property from the electrode provided on the imaging element layer 11 to the heater layer is reduced to the thin conductive property provided on the side surfaces of the actuator layer 14, the infrared cut filter layer 13, and the imaging element holder layer 12. Although it went through the member (not shown), it is not limited to this. FIG. 25 is a diagram illustrating a camera module 500B according to a modification.

  Specifically, as shown in FIG. 25, a conductive adhesive having conductivity is adopted as the adhesive KJ2 that fills the gap KG between the cover 20 and the optical unit 50, and the conductive adhesive is used as the actuator layer 14, red You may make it provide over the side surface of the outer cut filter layer 13 and the image pick-up element holder layer 12. FIG. According to this, it becomes possible to conduct electricity from the electrode of the imaging element layer 11 to the heater layer via the conductive adhesive.

It is a schematic diagram which shows schematic structure of the mobile telephone carrying the camera module which concerns on embodiment. It is a cross-sectional schematic diagram which paid its attention to the 1st housing | casing among mobile phones. It is a cross-sectional schematic diagram of a camera module. It is a cross-sectional schematic diagram of a lens layer. It is a lower surface external view of a lens layer. It is a figure which shows the mode of preparation of the lens structure layer which has a 3rd lens. It is an upper surface external view of a 1st parallel spring. It is a figure which shows the 1st parallel spring with which the lens layer was mounted | worn. It is a figure which shows the upper surface external view of an actuator layer. It is a figure which shows the side external view of an actuator layer. It is sectional drawing of the camera module in the plane parallel to the lamination direction of a lens layer. It is a figure which shows a mode that a lens layer moves with external force. It is sectional drawing of the camera module in the plane parallel to the lamination direction of a lens layer. It is sectional drawing of the camera module in the plane parallel to the lamination direction of a lens layer. It is a flowchart which shows the manufacturing process of a camera module. It is a top view which shows the structural example of the sheet | seat to prepare. It is a figure which shows typically a mode that the prepared sheet | seat was laminated | stacked sequentially and joined. It is a cross-sectional schematic diagram of an optical unit. It is a figure which shows the optical unit with which the cover was attached. It is a figure for demonstrating the process of ensuring the drive space of a lens layer. It is sectional drawing in the plane parallel to the lamination direction of the lens layer which concerns on a modification. It is sectional drawing in the plane parallel to the lamination direction of the lens layer which concerns on a modification. It is sectional drawing in the plane parallel to the lamination direction of the lens layer which concerns on a modification. It is sectional drawing in the plane parallel to the lamination direction of the lens layer which concerns on a modification. It is a figure which shows the camera module which concerns on a modification.

Explanation of symbols

500A, 500B Camera module 100 Mobile phone 11 Imaging element layer 111 Imaging element 12 Imaging element holder layer 13 Cut filter layer 13 Infrared cut filter layer 14 Actuator layer 15 First parallel spring 16, 16B, 16C, 16D, 16E Lens layer 17 Second parallel spring 20, 20B, 20C Cover 143 Actuator element CP center LJ1, LJ2 Optical axis EG1, EG3 circumscribed circle KB drive mechanism ML1 cross section (rectangular cross section)
NK inner wall

Claims (6)

A lens unit fabricated at the wafer level;
A first fixing part disposed on one main surface side of the lens part;
A second fixing portion disposed on the other main surface side of the lens portion;
A first elastic member that elastically connects the lens portion and the first fixing portion;
A second elastic member that elastically connects the lens portion and the second fixing portion;
A driving layer for driving a driven body including the lens unit, the first elastic member, and the second elastic member;
With
The second fixing portion is a housing that houses the driven body,
The image pickup apparatus in which the driven body hits the inner wall of the housing when an external force is applied to the driven body.   The longest distance from the optical axis to the outer edge of the cross section in a cross section of the lens section in a plane perpendicular to the optical axis of the lens section is longer than the shortest distance from the optical axis to the inner wall of the housing in the plane. Item 2. The imaging device according to Item 1.   The imaging device according to claim 1, wherein the lens unit includes one or more layers having lenses. A lens manufactured at the wafer level;
A first fixing part disposed on one main surface side of the lens part;
A second fixing portion disposed on the other main surface side of the lens portion;
A first elastic member that elastically connects the lens portion and the first fixing portion;
A second elastic member that elastically connects the lens portion and the second fixing portion;
A driving layer for driving a driven body including the lens unit, the first elastic member, and the second elastic member;
With
The second fixing portion is a housing that houses the driven body,
The cross-sectional shape of the lens part in a plane perpendicular to the optical axis of the lens part is a rectangle,
An imaging apparatus in which a longest distance from the center of the rectangular cross section to an outer edge of the rectangular cross section is longer than a shortest distance from the center of the rectangular cross section to the inner wall of the housing. A lens unit fabricated at the wafer level;
A first fixing part disposed on one main surface side of the lens part;
A second fixing portion disposed on the other main surface side of the lens portion;
A first elastic member that elastically connects the lens portion and the first fixing portion;
A second elastic member that elastically connects the lens portion and the second fixing portion;
A driving layer for driving a driven body including the lens unit, the first elastic member, and the second elastic member;
With
The second fixing portion is a housing that houses the driven body,
The cross-sectional shape of the lens part in a plane perpendicular to the optical axis of the lens part is a polygon having a circumscribed circle,
An imaging apparatus in which a radius of the circumscribed circle is longer than a shortest distance from an outer center of the circumscribed circle to an inner wall of the housing. A lens unit fabricated at the wafer level;
A first fixing part disposed on one main surface side of the lens part;
A second fixing portion disposed on the other main surface side of the lens portion;
A first elastic member that elastically connects the lens portion and the first fixing portion;
A second elastic member that elastically connects the lens portion and the second fixing portion;
A driving layer for driving a driven body including the lens unit, the first elastic member, and the second elastic member;
With
The second fixing portion is a housing that houses the driven body,
The driven body is a driving device that hits the inner wall of the housing when an external force is applied to the driven body.

Images