JP2007104288A - Imaging apparatus and method for assembling imaging apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an imaging apparatus capable of obtaining an image of high image quality although being capable of focusing operation, and to provide a method for assembling the same. <P>SOLUTION: A first lens L1 as a focusing lens and lenses L2 to L4 as fixed lenses can be aligned, so the lens L1 and lenses L2 to L4 are aligned and positioned with high precision during assembling operation to stop the lens L1 from exceeding a permissible range of misalignment even moved for focusing along the optical axis during operation, thereby obtaining an image of high picture quality. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a compact imaging lens, an imaging apparatus, and an assembling method of the imaging apparatus using a solid-state imaging device such as a CCD type image sensor or a CMOS type image sensor, and in particular, an assembling apparatus of an imaging apparatus and an imaging apparatus having a focusing mechanism. Regarding the method.

2. Description of the Related Art In recent years, an imaging apparatus equipped with an autofocus mechanism (hereinafter referred to as an AF mechanism) is mounted along with improvement in performance of an imaging apparatus using a CCD (Charged Coupled Device) type or a CMOS (Complementary Metal Oxide Semiconductor) type solid-state imaging element. Mobile phones are becoming popular. In addition, there is an increasing demand for further downsizing of these imaging devices. An image pickup apparatus having such an AF mechanism is disclosed in Patent Document 1, for example.
JP 2004-347890 A

  Incidentally, the imaging device disclosed in Patent Document 1 is configured to perform a focusing operation by fixing the lens closest to the subject and moving the two lenses on the image side in the optical axis direction. Here, since the imaging device used for a mobile phone etc. is miniaturized, the miniaturization request | requirement with respect to the full length of a lens has become strong. In general, when the total lens length is reduced, each lens has a strong refractive power, and the allowable range for the misalignment between the lenses is narrowed. However, as disclosed in Patent Document 1, the lens is used for the focusing operation. Is moved in the optical axis direction, it may exceed the allowable range for misalignment due to the problem of accuracy of parts, and a high-quality image may not be formed.

  The present invention has been made in view of the problems of the prior art, and an object of the present invention is to provide an imaging apparatus capable of obtaining a high-quality image while enabling a focusing operation, and an assembling method thereof. .

The imaging device according to claim 1, wherein the imaging device includes an imaging lens including a plurality of lenses and a solid-state imaging device.
In the imaging lens, an effective diameter of the most image side lens located closest to the image side is larger than an effective diameter of other lenses, and a focusing lens including at least the first lens located closest to the subject side is fixed to the imaging lens. The lens is configured to perform focusing by moving it in the optical axis direction with respect to the lens.
At the time of assembly, the focusing lens and the fixed lens can be aligned.

  According to the present invention, since the focusing lens and the fixed lens can be aligned at the time of assembly, the focusing lens and the fixed lens are aligned at the time of assembly to achieve high accuracy. When the focusing lens is moved in the operation, even when the focusing lens is moved in the optical axis direction, it is suppressed from exceeding the allowable range of misalignment, and thereby a high-quality image can be obtained.

  According to a second aspect of the present invention, in the invention of the first aspect, the imaging device moves to a space generated around the first lens due to a difference in outer diameter between the first lens and the most image side lens during focusing. At least a part of a focus actuator for driving the focusing lens is arranged.

  By arranging an actuator for driving all the lenses including the most image side lens in the optical axis direction as a focusing lens by using a space radially outside the lens having the smallest outer diameter, the outer dimension can be reduced. It is possible to provide an imaging apparatus capable of realizing a focusing operation while suppressing it.

  In addition, “the space generated around the minimum lens due to the difference between the outer diameter of the minimum lens and the outermost lens” is “the smallest lens as a result of the difference between the outer diameter of the minimum lens and the outermost lens. For example, when the smallest lens and the most image side lens are both held by the holding member, the space created around the smallest lens due to the difference in the outer diameter of the holding member is the “smallest lens”. Corresponds to a space formed around the minimum lens due to the difference between the outer diameter of the lens and the outer diameter of the most image side lens.

  According to a third aspect of the present invention, in the invention of the second aspect, the focusing lens is configured by only the first lens, and the alignment is performed by integrating the focus actuator and the first lens, Since this is performed by displacing the fixed lens in a direction crossing the optical axis, the weight of the focusing lens can be reduced to reduce the load on the actuator and to save energy. it can.

  According to a fourth aspect of the present invention, in the invention of the second aspect, the focusing lens is configured only by the first lens, and the alignment is performed by the holding frame that holds the first lens. On the other hand, since it is characterized by being displaced in a direction crossing the optical axis, alignment can be further easily performed.

  According to a fifth aspect of the present invention, in the invention according to any one of the first to fourth aspects, the actuator includes a voice coil motor. The voice coil motor is suitable for driving a focusing lens because it is relatively small and can be driven at high speed and with high precision.

  According to a sixth aspect of the present invention, in the invention according to any of the first to fifth aspects, the actuator includes a shape memory alloy, so that the size of the imaging apparatus can be reduced. A shape memory alloy refers to an alloy whose shape changes when a voltage is applied, and may be used in the form of a wire.

  An imaging apparatus according to a seventh aspect is the invention according to any one of the first to sixth aspects, wherein a substrate having an external connection terminal that holds the solid-state imaging element and transmits and receives an electrical signal; and an object side And a housing made of a light-shielding member is integrally formed, and the height of the imaging device in the optical axis direction of the imaging lens is 10 [mm] or less. Since it is a feature, a smaller imaging device can be obtained.

The imaging device assembly method according to claim 8, wherein the imaging device includes an imaging lens including a plurality of lenses and a solid-state imaging device.
In the imaging lens, an effective diameter of the most image side lens located closest to the image side is larger than an effective diameter of other lenses, and a focusing lens including at least the first lens located closest to the subject side is fixed to the imaging lens. The lens is configured to perform focusing by moving it in the optical axis direction with respect to the lens.
One of the focusing lens and the fixed lens is fixed after being aligned with respect to the other.

  According to the present invention, since one of the focusing lens and the fixed lens is fixed after being aligned with respect to the other, the focusing lens and the fixed lens are aligned during assembly. By positioning with high accuracy, even when the focusing lens is moved in the direction of the optical axis during operation, it is possible to suppress exceeding an allowable range of misalignment, thereby obtaining a high-quality image.

  According to a ninth aspect of the present invention, there is provided an imaging device assembly method according to the eighth aspect of the invention, wherein the focusing lens is constituted by only the first lens, and the alignment is performed by integrating the focus actuator and the first lens. In particular, it is performed by displacing the fixed lens in a direction crossing the optical axis.

  According to a tenth aspect of the present invention, there is provided an imaging device assembly method according to the eighth aspect, wherein the focusing lens is configured by only the first lens, and the centering holds the first lens. This is performed by displacing the holding frame in a direction crossing the optical axis.

  According to the present invention, it is possible to provide an imaging apparatus capable of obtaining a high-quality image while enabling a focusing operation.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a perspective view of an imaging device 50 according to the present embodiment, and FIGS. 2 and 3 are cross-sectional views of the imaging device 50 of FIG. 1 cut along a plane including the II-II line. 2 is in a non-energized state with respect to the coil of the actuator, and FIG. 3 is in a conductive state with respect to the coil of the actuator.

  The imaging apparatus 50 includes a CMOS image sensor 51 as a solid-state imaging device having a photoelectric conversion unit 51a, an imaging lens 10 as an imaging lens that causes the photoelectric conversion unit 51a of the image sensor 51 to capture a subject image, and an image sensor. IR cut filter F disposed between 51 and imaging lens 10, substrate 52 having external connection terminal 54 (FIG. 1) for holding image sensor 51 and transmitting and receiving electrical signals, and imaging lens An assembly housing 20 to be supported and an actuator (also referred to as a focus actuator) 30 for driving a focusing lens are provided, and these are integrally formed. The height Δ in the optical axis direction of the imaging apparatus 50 is 10 mm or less.

  In the image sensor 51, a photoelectric conversion unit 51a as a light receiving unit in which pixels (photoelectric conversion elements) are two-dimensionally arranged is formed in the center of a plane on the light receiving side. A processing circuit (not shown) is formed. Such a signal processing circuit includes a drive circuit unit that sequentially drives each pixel to obtain a signal charge, an A / D conversion unit that converts each signal charge into a digital signal, and a signal that forms an image signal output using the digital signal. It consists of a processing unit and the like. A number of pads (not shown) are arranged near the outer edge of the plane on the light receiving side of the image sensor 51, and are connected to the substrate 52 via wires W. The image sensor 51 converts the signal charge from the photoelectric conversion unit 51 a into an image signal such as a digital YUV signal, and outputs the image signal to a predetermined circuit on the substrate 52 via the wire W. Here, Y is a luminance signal, U (= R−Y) is a color difference signal between red and the luminance signal, and V (= BY) is a color difference signal between blue and the luminance signal. Note that the image sensor is not limited to the above CMOS image sensor, and other devices such as a CCD may be used.

  The substrate 52 includes a support flat plate 52a that supports the image sensor 51 and the outer cylinder 21 on one plane, and a flexible substrate 52b (FIG. 1) having one end connected to the support flat plate 52a.

  The support flat plate 52a has a large number of signal transmission pads provided on the surface thereof, which are connected to the wires W from the image sensor 51 described above and to the flexible substrate 52b.

  As described above, one end of the flexible substrate 52b is connected to the support flat plate 52a, and the support flat plate 52a and an external circuit (for example, a host device on which an imaging device is mounted) are connected via an external connection terminal 54 provided at the other end. Control circuit), and a voltage and a clock signal for driving the image sensor 51 are supplied from an external circuit, and a digital YUV signal can be output to the external circuit. Furthermore, the intermediate portion in the longitudinal direction of the flexible substrate 52b is flexible or easily deformable, and the deformation gives freedom to the orientation and arrangement of the external output terminals with respect to the support flat plate 52a.

  The assembly housing 20 made of a light-shielding member is disposed so as to surround the image sensor 51, and has an outer cylinder 21 having a lower end bonded to the support flat plate 52a using an adhesive B, and an inner side of the outer cylinder 21. The inner cylinder 22 is disposed, the movable cylinder 23 is disposed above the inner cylinder 22 and is movable, and the cover member 24 is disposed outside the movable cylinder 23.

  An IR cut filter F is attached to a flange portion 21 a extending radially inward from the inner periphery of the outer cylinder 21. The inner cylinder 22 whose outer periphery at the lower end is fitted to the outer cylinder 21 holds and holds these fixedly in the order of the second lens L2, the third lens L3, and the fourth lens L4 from the object side.

  The movable cylinder 23 has a cylindrical main body 23a and a flange portion 23b formed at the lower end which is the image side end. The main body 23a of the movable cylinder 23 includes a holder (also referred to as a holding frame) 25 that holds the first lens L1. The holder 25 includes a hollow cylindrical main body 25a having an inner periphery larger than the outer periphery of the first lens L1 (for example, a radius of 100 μm or more), and a flange portion 25b disposed on the image side of the first lens L1, The central opening is an aperture stop S. Further, a donut disk-shaped holding member 26 is attached to the object side of the first lens L1 on the inner periphery of the main body 25a. The first lens L1 has an optical axis formed by the holding member 26 and the flange portion 25b. Sandwiched in the direction.

  The lower surface of the flange portion 23 b of the moving cylinder 23 is in contact with the upper surface of a spring disk 27 whose outer peripheral side is fixed by a screw member 29 screwed to the upper end of the outer cylinder 21. The upper part of the main body 23 a of the moving cylinder 23 is in contact with the lower surface of the spring member 28 whose outer peripheral side is sandwiched between the cover member 24 attached to the upper end of the outer cylinder 21 and the yoke 31 of the actuator 30. The spring members 27 and 28 in the free state have substantially the shape shown in FIG. 2, that is, in the deformed state shown in FIG. 3, the moving cylinder 23 is urged downward by its elastic force.

  The actuator 30 which is an annular voice coil motor is sandwiched between the outer cylinder 21 and the cover member 24 in the space outside the first lens L1 in the radial direction and above the outer cylinder 21 and within the outer diameter thereof. The yoke 31 arranged as described above, a magnet 32 fixed in the yoke 31, and a coil 33 having a lower end attached to the flange portion 23b of the movable cylinder 23 are included. The plus terminal of the coil 33 is connected to the spring member 28 via a wiring H + extending through the outer wall of the main body 23 a of the movable cylinder 23. Further, the negative terminal of the coil 33 is connected to the spring member 27 via a wiring H− that extends through the outer wall of the flange portion 23 b of the movable cylinder 23. A part of the spring members 27 and 28 are connected to the substrate 52 through the outer wall of the outer cylinder 21 as wiring portions 27a and 28a (which are insulated from each other). The principle of driving the voice coil motor is well known and will be omitted. However, the magnet 32 is caused by the magnetic force generated by supplying electric power to the coil 33 from the outside via the spring members 27 and 28 and the wirings H + and H−. On the other hand, the coil 33 can be displaced according to the supplied electric power.

  The imaging lens 10 has, in order from the object side, a first lens L1 having a positive refractive power and a convex surface facing the object side, an aperture stop S, a second lens L2 having a negative refractive power, and a positive refractive power. The third lens L3 and the fourth lens L4 having negative refractive power are included. Each lens L1, L2, L3, L4 is housed inside the assembly housing 20 in a state where its optical axis and the center line of the outer cylinder 21 coincide with each other by being assembled by an assembly method described later. In the present embodiment, the fourth lens L4 constitutes the most image side lens, and the first lens L1 constituting the focusing lens located on the object side from the fourth lens L4 is the smallest lens having the smallest outer diameter. This structure is suitable for disposing the actuator 30 radially outward of the lens L1.

  The imaging lens 10 is used to form a subject image on a solid-state imaging device using the aperture stop S and the lenses L1, L2, L3, and L4 as an optical system. The aperture stop S is a member that determines the F number of the entire imaging lens system.

  The IR cut filter F held by the flange portion 21a of the outer cylinder 21 between the imaging lens 10 and the image sensor 51 is a member formed in, for example, a substantially rectangular shape or a circular shape.

  Further, a light-shielding mask SM is disposed between the third lens L3 and the fourth lens L4 to prevent unnecessary light from entering outside the effective diameter of the fourth lens L4 close to the solid-state image pickup device, and ghost And flare generation can be suppressed.

  A method for assembling the imaging device 50 according to the present embodiment will be described. First, the lower end of the outer cylinder 21 is bonded onto the support flat plate 52a to which the image sensor 51 is attached. An IR cut filter F is attached thereto, and the inner cylinder 22 to which the lenses L2 to L4 are fixed using the adhesive B so that the optical axes coincide with each other is fitted. Furthermore, after fixing the actuator 30 and the movable cylinder 23 to which the holder 25 is fixed to the upper end of the outer cylinder 21 using the cover member 24, the first lens L 1 is assembled in the holder 25 and temporarily assembled using the pressing member 26. To do.

  In this state, when the inspection light is incident from the first lens L1, an image is formed on the light receiving surface of the image sensor 51 via the lenses L1 to L4. Therefore, by analyzing the signal from the image sensor 51, the lens The degree of misalignment between L1 and the lenses L2 to L4 is known. Therefore, if the lens L1 is displaced in the direction orthogonal to the optical axis so as to suppress the misalignment, the optical axes of the lens L1 and the lenses L2 to L4 are aligned, and thus the center L is suppressed while maintaining the alignment state. Fixing the first lens L1 to the holder 25 via the member 26 completes the misalignment adjustment. The fixing of the first lens L1 is not limited to adhesion using an adhesive, but may be laser welding or the like.

  According to the present embodiment, since the first lens L1 that is a focusing lens and the lenses L2 to L4 that are fixed lenses can be aligned, the lens L1 and the lenses L2 to L2 are assembled during assembly. By aligning with L4 and positioning with high accuracy, even when the lens L1 is moved in the optical axis direction for focusing during operation, it is suppressed from exceeding the allowable range of misalignment. A high-quality image can be obtained.

  A usage mode of the imaging apparatus 50 described above will be described. FIG. 4 is a diagram illustrating a state in which the imaging device 50 is installed in a mobile phone 100 as a mobile terminal. FIG. 5 is a control block diagram of the mobile phone 100.

  In the imaging device 50, for example, the object-side end surface of the outer cylinder 21 in the imaging lens is provided on the back surface of the mobile phone 100 (the liquid crystal display unit side is the front surface), and is arranged at a position corresponding to the lower side of the liquid crystal display unit. Established.

  The external connection terminal 54 of the imaging device 50 is connected to the control unit 101 of the mobile phone 100 and outputs an image signal such as a luminance signal or a color difference signal to the control unit 101 side.

  On the other hand, as shown in FIG. 5, the mobile phone 100 controls each part in an integrated manner, and supports and inputs a control part (CPU) 101 that executes a program corresponding to each process, and a number and the like with keys. An input unit 60, a display unit 70 for displaying captured images and videos in addition to predetermined data, a wireless communication unit 80 for realizing various information communication with an external server, and a mobile phone 100 By a storage unit (ROM) 91 that stores necessary data such as system programs, various processing programs, and terminal IDs, and various processing programs and data executed by the control unit 101, or processing data, or the imaging device 50 And a temporary storage unit (RAM) 92 that is used as a work area for temporarily storing imaging data and the like.

  When the photographer holding the mobile phone 100 directs the optical axis of the imaging lens 10 of the imaging device 50 toward the subject, an image signal is captured by the image sensor 51. For example, by performing image plane AF processing or the like, The focus shift can be detected. Since the control unit 101 supplies power to the actuator 30 so as to drive the first lens L1 in a direction to eliminate this defocus, the spring members 27 and 28, the wirings H + and H− are supplied from the external connection terminal 54. Electric power is supplied to the coil 33 via. By balancing the magnetic force generated thereby and the urging forces of the deformed spring members 27 and 28, the movable cylinder 23 is moved to the optimum in-focus position between the position shown in FIG. 2 and the position shown in FIG. Since one lens L1 can be moved and held, an appropriate autofocus operation can be realized. If the driving force of the voice coil motor 30 disappears due to the interruption of power supply, the movable cylinder 23 returns to the state shown in FIG.

  Further, when the photographer presses the button BT shown in FIG. 4 with a desired photo opportunity, the release is performed, and the image signal is taken into the imaging device 50. The image signal input from the imaging device 50 is stored in the storage unit 92 or displayed on the display unit 70 by the control system of the mobile phone 100, and further externally as video information via the wireless communication unit 80. Will be sent to.

  FIG. 6 is a cross-sectional view similar to FIG. 2 of an imaging apparatus 150 according to the second embodiment that can be used in the mobile phone 100. In addition, this Embodiment attaches | subjects the same code | symbol about the structure shown with respect to Embodiment shown in FIGS. 1-3, and abbreviate | omits description.

  In FIG. 6, the outer cylinder 21 is composed of two parts, an upper part 21A and a lower part 21B. In the present embodiment, no restraining member is provided, and the first lens L1 is directly fixed to the holder 25. An aperture stop S is formed in the center of the flange portion 25b formed on the image side of the holder 25. A clearance of 100 μm or more is provided between the outer peripheral surface of the inner cylinder 22 and the inner peripheral surface of the upper portion 21 </ b> A and the inner peripheral surface of the movable cylinder 23.

  A method for assembling the imaging apparatus 150 according to the present embodiment will be described. First, the actuator 30 and the movable cylinder 23 to which the holder 25 holding the first lens L <b> 1 is fixed are fixed to the upper end of the upper portion 21 </ b> A of the outer cylinder 21 using the cover member 24. On the other hand, the lenses L <b> 2 to L <b> 4 are fixed using the adhesive B so that the optical axis coincides with the inner cylinder 22. The inner cylinder 22 is fitted into the lower part 21B bonded to the support flat plate 52a to which the image sensor 51 is attached. Furthermore, the lower end of the upper part 21A and the upper end of the lower part 21B are temporarily fixed.

  In this state, when the inspection light is incident from the first lens L1, an image is formed on the light receiving surface of the image sensor 51 via the lenses L1 to L4. Therefore, by analyzing the signal from the image sensor 51, the lens The degree of misalignment between L1 and the lenses L2 to L4 is known. Therefore, if the upper portion 21A is relatively displaced in the direction orthogonal to the optical axis with respect to the lower portion 21B so that the misalignment is suppressed, the optical axes of the lens L1 and the lenses L2 to L4 are aligned. The center misalignment adjustment is completed by fixing the upper portion 21A and the lower portion 21B to each other while maintaining the state. Such fixation is not limited to adhesion using an adhesive, but may be laser welding or the like.

  As a modification of the present embodiment, in the imaging device 150 of FIG. 6, the moving cylinder 23 is mounted together with the first lens L <b> 1 and the holder 25 using the fact that the magnet 32 and the coil 33 of the actuator 30 are not in contact with each other. The screw member 29 (that is, the outer cylinder 21) may be configured to be displaceable in the direction perpendicular to the optical axis. More specifically, the spring members 27 and 28 and the movable cylinder 23 are temporarily assembled in a state in which they can be relatively displaced, and after adjusting the misalignment between the lens L1 and the lenses L2 to L4, the alignment state is changed. The spring members 27 and 28 and the movable cylinder 23 can be fixed using a screw (not shown) or the like while being maintained. In such a case, there is an advantage that the outer cylinder 21 does not need to be divided.

  FIG. 7 is a cross-sectional view similar to FIG. 2 of an imaging apparatus 250 according to the second embodiment that can be used in the mobile phone 100. In addition, this Embodiment attaches | subjects the same code | symbol about the structure shown with respect to Embodiment shown in FIGS. 1-3, and abbreviate | omits description.

  In FIG. 7, the outer cylinder 21 includes two parts, an upper part 21A and a lower part 21B. In the present embodiment, no restraining member is provided, and the first lens L1 is directly fixed to the holder 25. An aperture stop S is formed in the center of the flange portion 25b formed on the image side of the holder 25. The inner cylinder 22 is configured to be fixed to the upper portion 21A without fitting into the lower portion 21B. A clearance of 100 μm or more is provided between the outer peripheral surface of the inner cylinder 22 and the inner peripheral surface of the upper portion 21 </ b> A and the inner peripheral surface of the movable cylinder 23.

  A method for assembling the imaging apparatus 250 according to the present embodiment will be described. First, the actuator 30 and the movable cylinder 23 to which the holder 25 holding the first lens L <b> 1 is fixed are fixed to the upper end of the upper portion 21 </ b> A of the outer cylinder 21 using the cover member 24. Further, the lenses L <b> 2 to L <b> 4 are fixed to the inner cylinder 22 using the adhesive B so that the optical axis coincides. A flange portion 21c protruding from the inner peripheral surface of the upper portion 21A placed with a jig (not shown) so that the first lens L1 side is positioned downward (that is, with the top and bottom reversed from FIG. 7). In addition, the end surface of the inner cylinder 22 on the second lens L2 side is bottomed and placed in an inspection apparatus (not shown) provided with an image sensor in a temporarily assembled state.

  In such a state, when inspection light is incident from the first lens L1, an image is formed on the light receiving surface of the image sensor of the inspection apparatus via the lenses L1 to L4. By analyzing the signal from the image sensor, The degree of misalignment between the lens L1 and the lenses L2 to L4 is known. Therefore, if the inner cylinder 22 is relatively displaced in the direction orthogonal to the optical axis with respect to the upper portion 21A so as to suppress misalignment, the optical axes of the lens L1 and the lenses L2 to L4 are aligned. The core deviation adjustment is completed by adhering and fixing the inner cylinder 22 to the upper portion 21A with the adhesive B while maintaining the core state. Such fixation is not limited to adhesion using an adhesive, but may be laser welding or the like.

  Thereafter, the upper part 21A to which the inner cylinder 22 is fixed is removed from an inspection device (not shown), and the upper part 21A is turned upside down so that the first lens L1 side is up, and the lower part is bonded onto the support plate 52a to which the image sensor 51 is attached. Fixing to the upper end of 21B completes the assembly.

  8 and 9 are top views of the imaging device 350 according to the fourth embodiment that can be used in the mobile phone 100. FIG. 8 shows a state where the actuator 30 ′ is not energized, and FIG. The actuator 30 'is energized. 10 and 11 are diagrams showing the relationship between the cam and the follower corresponding to FIGS. 8 and 9, respectively. Since the present embodiment is different from the embodiment shown in FIGS. 1 to 3 only in the configuration of the actuator, the description of the common configuration is omitted by attaching the same reference numerals.

  In the present embodiment, the actuator 30 '(hereinafter referred to as a wire SMA) uses a shape memory alloy in the form of a wire. The shape memory alloy refers to an alloy that is arbitrarily deformed by supplying electric power from the outside, and is described in detail in, for example, JP-T-2003-507625.

  Referring to FIGS. 2 and 3, the moving cylinder 23 ′ urged downward with respect to the cover member 24 by the spring plate 28 forms a follower 23c ′ (FIGS. 10 and 11) on the lower surface of the flange portion 23b ′. ing. On the other hand, the adjustment ring 35 (FIGS. 8 and 9) attached to the upper portion of the outer cylinder 21 has a cam portion 35a (FIG. 10, FIG. 10) in which the height continuously changes in the circumferential direction and the follower 23c ′ slides. 11).

  8 and 9, the left end of the wire SMA made of shape memory alloy is fixed by caulking to the outer cylinder 21, and the right end of the wire SMA is fixed to the moving cylinder 23 '. The left end of the wire SMA is electrically connected to the wiring H +, and the right end of the wire SMA is electrically connected to the wiring H−. The movable cylinder 23 'is connected to the outer cylinder 21 by a tension spring 36, and is biased clockwise in FIGS.

  When power is supplied to the wire SMA via the wirings H + and H− by the control of the control unit 101 (FIG. 5), the wire SMA is reduced from the state shown in FIG. 8 by an amount corresponding to the power. The state changes to the state shown in FIG. 9 against the urging force of the tension spring 36. At this time, the wire SMA rotates the moving cylinder 23 ′ with respect to the outer cylinder 21, but the moving cylinder 23 ′ holds the lens L1 by moving the follower 23c ′ along the cam 35a as shown in FIG. As it moves, the outer cylinder 21 moves in the optical axis direction, so that an appropriate focusing operation can be performed. If the wire SMA returns to its original shape due to the interruption of power supply, the movable cylinder 23 ′ returns to the state shown in FIGS.

  The present invention has been described above with reference to the embodiments. However, the present invention should not be construed as being limited to the above-described embodiments, and can be modified or improved as appropriate. For example, as the actuator, various drive sources can be used in addition to the above-described embodiment.

It is a perspective view of imaging device 50 concerning a 1st embodiment. It is sectional drawing which cut | disconnected the imaging device 50 of FIG. 1 in a non-energized state along the surface containing an II-II line. It is sectional drawing which cut | disconnected the imaging device 50 of FIG. 1 in an electricity supply state along the surface containing an II-II line. It is a figure which shows the state equipped with the imaging device 50 in the mobile telephone 100 as a portable terminal. 3 is a control block diagram of the mobile phone 100. FIG. It is a perspective view of imaging device 150 concerning a 2nd embodiment. It is a perspective view of the imaging device 250 concerning 3rd Embodiment. It is the figure which looked at the actuator 30 'of the imaging device 350 concerning 4th Embodiment in the optical axis direction. It is the figure which looked at the actuator 30 'of the imaging device 350 concerning 4th Embodiment in the optical axis direction. It is a figure which shows the relationship of a cam follower corresponding to FIG. It is a figure which shows the relationship of a cam follower corresponding to FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Imaging lens 20 Assembly housing | casing 21 Outer cylinder 21A Upper part 21B Lower part 21a Flange part 22 Inner cylinder 23 Moving cylinder 23a Main body 23b Flange part 23c Follower 23c Cylindrical surface 24 Cover member 25 Holder 25a Main body 25b Flange part 26 Holding member 27 Spring member 27a Wiring portion 28 Spring member 29 Screw member 30, 30 ′ Actuator 31 Yoke 32 Magnet 33 Coil 35 Adjustment ring 35a Cam portion 50 Imaging device 51 Image sensor 51a Photoelectric conversion portion 52 Substrate 52a Support plate 52b Flexible substrate 54 External connection terminal 60 Input Unit 70 Display unit 80 Wireless communication unit 92 Storage unit 100 Mobile phone 101 Control unit 150 Imaging device 250 Imaging device 350 Imaging device B Adhesive BT Button F IR cut filter H +, H- Wirings L1 to L 4 Lens S Aperture stop SM Shading mask SMA Wire W Wire

Claims (10)

In an imaging device having an imaging lens composed of a plurality of lenses and a solid-state imaging device,
In the imaging lens, an effective diameter of the most image side lens located closest to the image side is larger than an effective diameter of other lenses, and a focusing lens including at least the first lens located closest to the subject side is fixed to the imaging lens. The lens is configured to perform focusing by moving it in the optical axis direction with respect to the lens.
An imaging apparatus characterized in that the focusing lens and the fixed lens can be aligned when assembled.   At least a part of a focus actuator for driving a focusing lens that moves during focusing is disposed in a space generated around the first lens due to a difference in outer diameter between the first lens and the most image side lens. The imaging apparatus according to claim 1, wherein the imaging apparatus is characterized.   The focusing lens is constituted only by the first lens, and the alignment is performed by displacing the focus actuator and the first lens integrally in a direction intersecting the optical axis with respect to the fixed lens. The imaging apparatus according to claim 2, wherein the imaging apparatus is performed.   The focusing lens includes only the first lens, and the alignment is performed by displacing the first lens in a direction intersecting the optical axis with respect to a holding frame that holds the first lens. The imaging device according to claim 2.   The imaging apparatus according to claim 1, wherein the actuator includes a voice coil motor.   The imaging device according to claim 1, wherein the actuator includes a shape memory alloy.   A substrate having an external connection terminal for holding the solid-state imaging device and transmitting / receiving an electric signal, and a housing made of a light-shielding member having an opening for light incidence from the object side are integrally formed. The imaging apparatus according to claim 1, wherein a height of the imaging lens in the optical axis direction of the imaging apparatus is 10 [mm] or less. In an assembling method of an imaging device having an imaging lens composed of a plurality of lenses and a solid-state imaging device,
In the imaging lens, an effective diameter of the most image side lens located closest to the image side is larger than an effective diameter of other lenses, and a focusing lens including at least the first lens located closest to the subject side is fixed to the imaging lens. The lens is configured to perform focusing by moving it in the optical axis direction with respect to the lens.
An assembling method of an imaging apparatus, wherein one of the focusing lens and the fixed lens is fixed after being aligned with respect to the other.   The focusing lens is constituted only by the first lens, and the alignment is performed by displacing the focus actuator and the first lens integrally in a direction intersecting the optical axis with respect to the fixed lens. 9. The method of assembling an image pickup apparatus according to claim 8, wherein the method is performed.   The focusing lens includes only the first lens, and the alignment is performed by displacing the first lens in a direction intersecting the optical axis with respect to a holding frame that holds the first lens. A method for assembling the imaging apparatus according to claim 8.

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