JP2013222132A - Camera module - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a camera module that allows a simple structure suitable for miniaturization and thinness to achieve an image of high quality.SOLUTION: According to an embodiment, the camera module includes an apodizer 32 that serves as a diaphragm mechanism and an optical image stabilizer (OIS) 31 that serves as a vibration correction part. The diaphragm mechanism adjusts the amount of light to be taken in and advanced to a pixel part by an imaging optical system. The vibration correction part performs vibration correction of a subject image. The diaphragm mechanism includes a light modulation element, and the light modulation element is capable of adjusting the amount of light allowed to pass through in accordance with an application voltage. The vibration correction part includes a liquid crystal element, and the liquid crystal element is capable of adjusting a refraction amount of incident light in accordance with a voltage distribution. The diaphragm mechanism and the vibration correction part are integrally formed to interpose a glass substrate 42 serving as a support substrate transmitting light.

Description

  Embodiments described herein relate generally to a camera module.

  2. Description of the Related Art Conventionally, a camera module having a camera shake correction function for suppressing image blur due to camera shake during shooting is known. Some camera modules use a diaphragm with gradation on the outer edge as a mechanism for adjusting the amount of light captured by the lens, thereby achieving both resolution and sharpness. . It is desired that these functions for obtaining a high-quality image can be realized by a simple configuration suitable for downsizing and thinning in a camera module mounted on a portable electronic device.

JP 2007-248604 A JP 2005-352318 A

  An object of one embodiment of the present invention is to provide a camera module that can realize a function for obtaining a high-quality image with a simple configuration suitable for downsizing and thinning.

  According to one embodiment of the present invention, the camera module includes an imaging optical system, a pixel unit, a diaphragm mechanism unit, a camera shake correction unit, and a focus adjustment unit. The imaging optical system captures light from the subject. The imaging optical system forms a subject image. The pixel unit captures a subject image. The aperture mechanism unit adjusts the amount of light that is captured by the imaging optical system and travels to the pixel unit. The camera shake correction unit performs camera shake correction of the subject image. The focus adjustment unit performs focus adjustment of the imaging optical system. The aperture mechanism unit includes a light modulation element. The light modulation element can adjust the amount of light passing therethrough according to the applied voltage. The camera shake correction unit includes a liquid crystal element. The liquid crystal element can adjust the amount of refraction of incident light in accordance with the voltage distribution. The focus adjustment unit includes a liquid crystal element. The liquid crystal element can adjust the amount of refraction of incident light according to the applied voltage. The aperture mechanism unit, the camera shake correction unit, and the focus adjustment unit are integrally configured with a support substrate through which light is transmitted.

1 is a block diagram showing a schematic configuration of a digital camera including a camera module according to an embodiment. FIG. 3 is a schematic cross-sectional view illustrating a schematic configuration of a liquid crystal unit and an imaging optical system. The cross-sectional schematic diagram which shows schematic structure of the part which comprises an apodizer among liquid crystal parts. The front schematic diagram of the liquid crystal element in the case of applying a voltage. The cross-sectional schematic diagram of a liquid crystal element in the case of applying a voltage. The figure explaining the optical characteristic at the time of applying the aperture_diaphragm | restriction which gave gradation to the outer edge part. The block diagram which shows the structure for controlling the drive of an apodizer among camera modules. The flowchart which shows the procedure which controls the drive of an apodizer. The cross-sectional schematic diagram which shows schematic structure of the part which comprises OIS among liquid crystal parts. The figure explaining the application and distribution of the voltage in a 2nd electrically conductive film. The block diagram which shows the structure for controlling the drive of OIS among camera modules. The block diagram which shows the modification of the structure for controlling the drive of OIS. The cross-sectional schematic diagram which shows the modification of the part which comprises OIS. The cross-sectional schematic diagram which shows schematic structure of the part which comprises AF part among liquid crystal parts. The block diagram which shows the structure for controlling the drive of a liquid-crystal part among camera modules. The cross-sectional schematic diagram which shows schematic structure of a liquid-crystal part among the camera modules concerning the modification of embodiment.

  Hereinafter, a camera module according to an embodiment will be described in detail with reference to the accompanying drawings. In addition, this invention is not limited by this embodiment.

(Embodiment)
FIG. 1 is a block diagram illustrating a schematic configuration of a digital camera including the camera module according to the embodiment. The digital camera 1 includes a camera module 2 and a post-processing unit 3.

  The camera module 2 includes a front lens 11, a liquid crystal unit 12, a rear lens 13, a solid-state imaging device 10, a control unit 16, and an angular velocity sensor 17. The post-processing unit 3 includes an image signal processor (ISP) 21, a storage unit 22, and a display unit 23. In addition to the digital camera 1, the camera module 2 is applied to an electronic device such as a mobile terminal with a camera.

  The front lens 11 and the rear lens 13, which are imaging optical systems, capture light from a subject and form a subject image. The liquid crystal unit 12 includes various liquid crystal elements described later. The solid-state imaging device 10 is, for example, a complementary metal oxide semiconductor (CMOS) image sensor. The solid-state imaging device 10 may be a CCD (charge coupled device) in addition to a CMOS image sensor.

  The solid-state imaging device 10 includes a pixel unit 14 and an imaging processing circuit 15. The pixel unit 14 converts the light captured by the imaging optical system into signal charges in the photodiode, and captures a subject image. The imaging processing circuit 15 performs signal processing of the image signal from the pixel unit 14. The control unit 16 controls driving of the liquid crystal unit 12. The angular velocity sensor 17 detects blurring of the digital camera 1. As the angular velocity sensor 17, for example, a gyro sensor is used.

  The ISP 21 performs signal processing of an image signal obtained by imaging with the solid-state imaging device 10. The storage unit 22 stores an image that has undergone signal processing in the ISP 21. The storage unit 22 outputs an image signal to the display unit 23 according to a user operation or the like. The display unit 23 displays an image according to the image signal input from the ISP 21 or the storage unit 22. The display unit 23 is, for example, a liquid crystal display.

  FIG. 2 is a schematic cross-sectional view illustrating a schematic configuration of the liquid crystal unit and the imaging optical system. The liquid crystal unit 12 is disposed, for example, in the optical path between the front lens 11 and the rear lens 13. For example, the front lens 11, the liquid crystal unit 12, and the rear lens 13 are mounted in a lens holder (not shown).

  The liquid crystal unit 12 includes an OIS (optical image stabilizer) 31, an apodizer 32, and an AF (auto focus) unit 33. The OIS 31 is a camera shake correction unit that performs camera shake correction of a subject image. The apodizer 32 is a diaphragm mechanism unit that adjusts the amount of light that is captured by the imaging optical system and travels to the pixel unit 14. The AF unit 33 is a focus adjustment unit that performs focus adjustment of the imaging optical system.

  The OIS 31, the apodizer 32, and the AF unit 33 include liquid crystal elements 34, 35, and 36, respectively. In the liquid crystal unit 12, each internal layer is sandwiched between two glass substrates 41 and 44. The OIS 31, the apodizer 32, and the AF unit 33 are integrally configured with the glass substrates 42 and 43 inside the liquid crystal unit 12 interposed therebetween. The glass substrates 41, 42, 43, and 44 function as a support substrate that transmits light.

  FIG. 3 is a schematic cross-sectional view showing a schematic configuration of a portion of the liquid crystal unit that constitutes the apodizer. The apodizer 32 includes a first polarizing plate 48, a glass substrate 42, a first conductive film 45, a liquid crystal element 35, a dielectric layer 47, a second conductive film 46, a glass substrate 43, and a second polarizing plate 49.

  The liquid crystal element 35 functions as a light modulation element that can adjust the amount of light to be transmitted according to the applied voltage. The liquid crystal element 35 is provided around the optical axis of the imaging optical system. The liquid crystal element 35 is formed, for example, as a flat surface on the first conductive film 45 side and a curved surface close to a spherical surface on the second conductive film 46 side. The dielectric layer 47 occupies a portion other than the liquid crystal element 35 between the first and second conductive films 45 and 46. The liquid crystal element 35 is formed, for example, by preparing a dielectric layer 47 having a concave portion having a desired curved shape and introducing a liquid crystal material into the concave portion. The dielectric layer 47 is configured using a dielectric material having a high dielectric constant with respect to the liquid crystal material.

  The first and second conductive films 45 and 46 which are transparent electrodes are configured using a conductive transparent material, for example, ITO. A voltage is applied between the first and second conductive films 45 and 46. The glass substrates 42 and 43 sandwich each part from the first conductive film 45 to the second conductive film 46.

  The first polarizing plate 48 is provided on the incident side surface of the glass substrate 42. The first polarizing plate 48 transmits first linearly polarized light that is linearly polarized light in a predetermined vibration direction. The first polarizing plate 48 makes the first linearly polarized light incident on the liquid crystal element 35.

  The second polarizing plate 49 is provided on the exit side surface of the glass substrate 43. The second polarizing plate 49 transmits the second linearly polarized light that is linearly polarized light in a predetermined vibration direction. The vibration direction of the first linearly polarized light and the vibration direction of the second linearly polarized light are perpendicular to each other. The first and second polarizing plates 48 and 49 constitute a crossed Nicol in which polarization characteristics are different from each other by 90 degrees and are connected in series.

  FIG. 4 is a schematic front view of the liquid crystal element when a voltage is applied. FIG. 5 is a schematic cross-sectional view of the liquid crystal element when a voltage is applied. The liquid crystal element 35 adjusts the amount of light by shielding a part of the incident light in a state where a voltage is applied. The shading shown in the drawing represents that the amount of light that passes through becomes smaller as it becomes darker, tone, and black.

  As shown in FIG. 4, the liquid crystal element 35 forms a gradation such that the amount of transmitted light decreases as the distance from the center position increases at the outer edge of the light transmitting region. In the cross section shown in FIG. 5, the liquid crystal element 35 is configured such that the incident-side surface of the light transmitting region has a curved surface close to a spherical surface.

  The dielectric layer 47 lowers the voltage applied to the liquid crystal element 35 as the thickness in the direction of the optical axis of the imaging optical system increases. In the liquid crystal element 35, when a voltage is applied through the dielectric layer 47, the alignment characteristics of the liquid crystal molecules are set such that the amount of light transmitted is, for example, a distribution close to a Gaussian distribution.

  The first polarizing plate 48 selectively transmits the first linearly polarized light out of the incident light and advances it to the liquid crystal element 35. The liquid crystal element 35 converts the first linearly polarized light into the second linearly polarized light according to the applied voltage. The second polarizing plate 49 selectively transmits the second linearly polarized light out of the light from the liquid crystal element 35.

  For example, when a voltage is applied, the liquid crystal element 35 gradually decreases the amount of light that is converted into the second linearly polarized light as the distance from the center position increases in the outer edge portion of the light transmitting region. As a result, the apodizer 32 functions as a diaphragm with gradation on the outer edge. For example, the liquid crystal element 35 converts all the first linearly polarized light into the second linearly polarized light while the application of the voltage is stopped. Thereby, the apodizer 32 transmits all of the incident light.

  FIG. 6 is a diagram for explaining optical characteristics in the case of applying a diaphragm having a gradation at the outer edge. Here, a point spread function (PSF) at the center of the screen is shown. The upper part of the figure shows an example of a PSF in the case of applying a so-called binary type diaphragm in which only two types of a part that transmits light without gradation and a part that blocks light are distributed. The lower part of the figure shows an example of a PSF when a diaphragm with gradation is applied.

  Comparing two PSF graphs, it can be seen that the expansion of the skirt portion of the graph is greatly reduced by providing gradation to the aperture. PSF shows the same tendency not only at the center of the screen but also at the outer edge of the screen. In the vicinity of the gradation portion of the aperture, light diffraction is suppressed. In this way, by employing a diaphragm having a gradation at the outer edge, it is possible to improve imaging performance and widen the imaging range, and to achieve both resolution and sharpness.

  The camera module 2 can acquire an image with a high resolution by causing the apodizer 32 to function in the case of shooting in a bright environment. When shooting in a dark environment, the camera module 2 stops the function of the apodizer 32 to increase the sensitivity of light and obtain an image with good contrast.

  FIG. 7 is a block diagram showing a configuration for controlling the driving of the apodizer in the camera module. An analog gain (AG) setting unit 51 in the imaging processing circuit 15 sets AG according to the illuminance at the time of shooting. The apodizer control unit 52 in the control unit 16 controls the driving of the apodizer 32 according to the AG set in the AG setting unit 51.

  FIG. 8 is a flowchart showing a procedure for controlling the driving of the apodizer. The apodizer control unit 52 compares the AG set by the AG setting unit 51 with a preset threshold value Th (step S1). When AG <Th is satisfied (step S1, Yes), the apodizer control unit 52 turns on the apodizer 32 by applying a voltage to the first and second conductive films 45 and 46 (step S2).

  If AG <Th is not satisfied (No in step S1), the apodizer control unit 52 turns off the apodizer 32 by stopping the application of voltage to the first and second conductive films 45 and 46. (Step S3). As a result, the camera module 2 ends the drive control of the apodizer 32.

  The camera module 2 is not limited to the case where the apodizer 32 is controlled only on and off, but by adjusting the voltage applied to the first and second conductive films 45 and 46, the light transmitted through the apodizer 32 can be controlled. It is also possible to adjust the amount. Thereby, the camera module 2 can obtain a higher quality image according to the illuminance.

  The light modulation element applied to the apodizer 32 is not limited to the liquid crystal element 35, and may be any element that can adjust the amount of light passing therethrough according to the applied voltage. The light modulation element may be, for example, an electrochromic element. An electrochromic element has a property of changing light transmittance by an electrochemical redox reaction. Even when an electrochromic element is applied as the light modulation element, the apodizer 32 can function as a diaphragm having gradation at the outer edge.

  FIG. 9 is a schematic cross-sectional view showing a schematic configuration of a portion of the liquid crystal portion that constitutes the OIS. The OIS 31 includes a glass substrate 41, a first conductive film 53, a liquid crystal element 34, a second conductive film 54, and a glass substrate 42. In this embodiment, the glass substrate 42 is shared with the apodizer 32 shown in FIG.

  The liquid crystal element 34 is configured such that the amount of refraction of incident light can be adjusted according to the potential difference distribution. The liquid crystal element 34 is a layer having a substantially constant thickness. The first and second conductive films 53 and 54 which are transparent electrodes are configured using a conductive transparent material, for example, ITO. A voltage is applied between the first and second conductive films 53 and 54. The glass substrates 41 and 42 sandwich each part from the first conductive film 53 to the second conductive film 54.

  For example, the first conductive film 53 is set to the same potential as the ground. A plurality of voltages are simultaneously applied to the second conductive film 54. By appropriately varying each voltage applied to the second conductive film 54, the second conductive film 54 causes a voltage gradient in the two-dimensional direction formed by the electrode surface.

  FIG. 10 is a diagram for explaining voltage application and distribution in the second conductive film. In the drawing, the second conductive film 54 is shown as a plane perpendicular to the optical axis. In the rectangular second conductive film 54, voltages V <b> 1 and V <b> 2 are applied in the vicinity of two long sides facing each other. Voltages V3 and V4 are respectively applied in the vicinity of two short sides facing each other in the second conductive film 56.

  For example, when V1 <V2 and V3 <V4 are satisfied, a voltage gradient is generated in the second conductive film 56 so as to become a lower potential from the upper left to the lower right in the drawing. The voltages V <b> 1 to V <b> 4 can be appropriately adjusted according to the direction and amount of camera shake, including the magnitude relationship.

  In the liquid crystal element 34, the orientation of liquid crystal molecules is controlled by application of voltage from the first and second conductive films 53 and 54. The liquid crystal element 34 refracts incident light according to the orientation of liquid crystal molecules. The OIS 31 can change the amount of light refraction in the liquid crystal element 34 in the two-dimensional direction by applying a voltage with a gradient in the two-dimensional direction to the liquid crystal element 34.

  FIG. 11 is a block diagram showing a configuration for controlling the driving of the OIS in the camera module. The angular velocity sensor 17 detects and outputs the amount of camera shake during shooting. The OIS control unit 55 of the control unit 16 controls the driving of the OIS 31 according to the amount of camera shake input from the angular velocity sensor 17.

  The OIS controller 55 adjusts the voltages V <b> 1 to V <b> 4 applied to the liquid crystal element 34 so that the light is deflected in a direction and an amount that cancels image movement due to camera shake. Thereby, the OIS 31 performs camera shake correction in the two-dimensional direction. The camera module 2 can obtain a high-quality image in which the influence of camera shake is suppressed. For example, in the conventional lens shift system, the driving force for moving the lens increases as the weight of the lens to be moved increases. The OIS 31 of the present embodiment can avoid such an increase in driving force by applying the liquid crystal element 34.

  The OIS 31 is not limited to the one that realizes the adjustment of the amount of light refraction in the two-dimensional direction by controlling the voltage applied to one liquid crystal element 34. The OIS 31 may adjust the amount of light refraction in the two-dimensional direction by combining, for example, two liquid crystal elements 34 having different voltage distribution directions. Also in this case, the OIS 31 can perform camera shake correction that suppresses the influence of camera shake in the two-dimensional direction.

  FIG. 12 is a block diagram illustrating a modification of the configuration for controlling the driving of the OIS. The angular velocity detection unit 56 in the control unit 16 detects the amount of camera shake from the image captured by the solid-state imaging device 10. The angular velocity detection unit 56 obtains the amount of camera shake, for example, through image processing that extracts a shift between images captured continuously. The OIS control unit 55 controls the driving of the OIS 31 according to the amount of camera shake detected by the angular velocity detection unit 56.

  Also in this case, the camera module 2 can obtain a high-quality image in which the influence of camera shake is suppressed. The OIS control unit 55 may control the driving of the OIS 31 according to both the detection result by the angular velocity sensor 17 (see FIG. 11) and the detection result by the angular velocity detection unit 56 of this modification.

  FIG. 13 is a schematic cross-sectional view showing a modified example of the portion constituting the OIS. The OIS 60 includes a glass substrate 41, a first conductive film 53, a liquid crystal element 61, a dielectric layer 62, a second conductive film 54, and a glass substrate 42.

  The surface of the dielectric layer 62 on the second conductive film 54 side is parallel to the electrode surface of the second conductive film 54, whereas the surface on the liquid crystal element 61 side is relative to the electrode surface of the second conductive film 54. Have a tilt. In the cross section shown, the dielectric layer 62 has a wedge shape. The liquid crystal element 61 occupies a portion other than the dielectric layer 62 between the first and second conductive films 53 and 54. In the liquid crystal element 61, the surface on the first conductive film 53 side is parallel to the electrode surface of the first conductive film 53, whereas the surface on the dielectric layer 62 side is relative to the electrode surface of the first conductive film 53. Have a tilt.

  In the cross section shown in the drawing, the liquid crystal element 61 has a wedge shape that is inverted up and down with respect to the dielectric layer 62. The dielectric layer 62 and the liquid crystal element 61 are integrated with the inclined surfaces that are inclined with respect to the electrode surface of the first conductive film 53 and the electrode surface of the second conductive film 54. The dielectric layer 62 is configured using a dielectric material having a high dielectric constant with respect to the liquid crystal material. A voltage is applied between the first and second conductive films 53 and 54.

  The refractive index n1 of the liquid crystal element 61 changes according to the applied voltage. The refractive index n2 of the dielectric layer 62 is constant. For example, when the voltage Vc is applied to the first and second conductive films 53 and 54, n1 = n2. In this case, the light transmitted through the liquid crystal element 61 is not refracted at the interface with the dielectric layer 62 and passes through the dielectric layer 62 while maintaining the traveling direction.

  When the applied voltage of the first and second conductive films 53 and 54 is changed from Vc, n1 ≠ n2. In this case, the light transmitted through the liquid crystal element 61 is refracted at the interface with the dielectric layer 62, the traveling direction is bent, and the light passes through the dielectric layer 62.

  The dielectric layer 62 is configured to increase in thickness in the optical axis direction as it goes from top to bottom in parallel with the paper surface in the figure. As the thickness of the dielectric layer 62 increases, the voltage applied to the liquid crystal element 61 decreases. The OIS 60 adjusts the voltage gradient in one direction parallel to the electrode surface. Thereby, the OIS 60 changes the amount of light refraction in the liquid crystal element 61 in one direction. In the present modification, the OIS 60 does not need to apply a plurality of voltages to the second conductive film 54, so that the number of wirings can be reduced.

  The mode of providing the liquid crystal element 61 and the dielectric layer 62 is not limited to the case described in the present embodiment, and may be changed as appropriate. In the OIS 60, the dielectric layer 62 may be disposed on the first conductive film 53 side where light is incident, and the liquid crystal element 61 may be disposed on the second conductive film 54 side where light is emitted.

  The OIS 60 uses two combinations of the liquid crystal element 61 and the dielectric layer 62, and makes it possible to adjust the amount of light refraction in the two-dimensional direction by changing the distribution direction of the thickness of the dielectric layer 62. To do. In FIG. 13, only one set in which the liquid crystal element 61 and the dielectric layer 62 are combined is illustrated.

  The OIS control unit 55 adjusts the applied voltage so that the light is deflected in a direction and amount that cancels the movement of the image due to camera shake. Thereby, the OIS 60 performs camera shake correction in the two-dimensional direction. The camera module 2 can obtain a high-quality image in which the influence of camera shake is suppressed. The liquid crystal unit 12 shown in FIG. 2 may be applied with the OIS 60 of this modification instead of the OIS 31.

  FIG. 14 is a schematic cross-sectional view showing a schematic configuration of a portion of the liquid crystal portion that constitutes the AF portion. The AF unit 33 includes a glass substrate 43, a first conductive film 65, a liquid crystal element 36, a dielectric layer 64, a second conductive film 66, and a glass substrate 44. In this embodiment, the glass substrate 43 is shared with the apodizer 32 shown in FIG.

  The liquid crystal element 36 is provided around the optical axis of the imaging optical system. The liquid crystal element 36 is formed, for example, as a flat surface on the first conductive film 65 side and a curved surface close to a spherical surface on the second conductive film 66 side. The dielectric layer 64 occupies a portion other than the liquid crystal element 36 between the first and second conductive films 65 and 66. The liquid crystal element 36 is formed, for example, by preparing a dielectric layer 64 having a concave portion having a desired curved shape and introducing a liquid crystal material into the concave portion. The dielectric layer 64 is configured using a dielectric material having a high dielectric constant with respect to the liquid crystal material.

  The first and second conductive films 65 and 66 are configured using a conductive transparent material, for example, ITO. A voltage is applied between the first and second conductive films 65 and 66. The glass substrates 43 and 44 sandwich each part from the first conductive film 65 to the second conductive film 66.

  The dielectric layer 62 reduces the voltage applied to the liquid crystal element 61 as the thickness in the direction of the optical axis of the imaging optical system increases. The liquid crystal element 36 adjusts the focus in accordance with the voltage applied via the dielectric layer 62.

  The AF unit 33 is not limited to the configuration to which the dielectric layer 62 is applied. For example, the AF unit 33 may be configured to adjust the focus by the liquid crystal element 36 by providing the liquid crystal element 36 with a concentric transparent electrode and adjusting the voltage applied to each transparent electrode.

  The liquid crystal unit 12 shown in FIG. 2 is configured by integrating the OIS 31 shown in FIG. 9 or the OIS 60 shown in FIG. 13, the apodizer 32 shown in FIG. 3, and the AF unit 33 shown in FIG. The OIS 31 or 60, the apodizer 32, and the AF unit 33 share part of the glass substrate, thereby reducing the number of parts and reducing the size of the camera module 2 compared to the case where each component is installed separately. It can be made thinner.

  Since the liquid crystal unit 12 can divert the same process using a common material for many elements of the OIS 31 or 60, the apodizer 32, and the AF unit 33, each component is separated. The manufacturing process can be simplified as compared with the case of forming them. As described above, the camera module 2 can realize a function for obtaining a high-quality image with a simple configuration suitable for downsizing and thinning.

  FIG. 15 is a block diagram illustrating a configuration for controlling driving of the liquid crystal unit in the camera module. The camera module 2 has a configuration for controlling the apodizer 32 (see FIG. 7), a configuration for controlling the OIS 31 (see FIG. 11), and a configuration for controlling the AF unit 33. Control the overall drive.

  The control unit 16 includes a focus deviation detection unit 71, an AF control unit 72, an apodizer control unit 52, and an OIS control unit 55. Here, the description which overlaps with the above about the control of the apodizer 32 and the control of the OIS 31 is omitted. In addition, as a structure for controlling OIS31, it may replace with the structure shown in FIG. 11, and may apply the structure shown in FIG. Further, the OIS 60 may be applied to the liquid crystal unit 12 instead of the OIS 31.

  The focus deviation detection unit 71 detects the amount of focus deviation through, for example, either phase difference detection or contrast detection. For example, the focus shift detection unit 71 searches for a state in which the contrast increases while driving the AF unit 33, and detects a focus shift amount. Alternatively, the focus shift detection unit 71 detects a focus shift amount from a phase difference between an image captured by the solid-state imaging device 10 and an image captured by a dedicated AF sensor (not shown).

  The AF control unit 72 controls the driving of the AF unit 33 by adjusting the voltage applied to the first and second conductive films 65 and 66 in accordance with the shift amount detected by the focus shift detection unit 71. Under the control of the AF control unit 72, the AF unit 33 is driven into a focused state.

  The camera module 2 is not limited to the configuration in which the OIS 31, the apodizer 32, and the AF unit 33 are integrated. The camera module 2 may be configured to integrally include two of the OIS 31, the apodizer 32, and the AF unit 33. For example, the camera module 2 may include one of the OIS 31 and the apodizer 32 alone. The OIS 31 may be combined with a conventionally known aperture mechanism or focus adjustment mechanism. The apodizer 32 may be combined with a conventionally known camera shake correction mechanism or focus adjustment mechanism. The OIS 31, the apodizer 32, and the AF unit 33 may be provided at any position in the optical path to the pixel unit 14.

  FIG. 16 is a schematic cross-sectional view illustrating a schematic configuration of a liquid crystal unit in a camera module according to a modified example of the embodiment. The liquid crystal unit 80 is disposed, for example, in the optical path between the front lens 11 and the rear lens 13. The liquid crystal unit 80 includes an optical image stabilizer (OIS) 31 and an apodizer 32. In the liquid crystal unit 80, internal layers are sandwiched between two glass substrates 41 and 43. The OIS 31 and the apodizer 32 are integrally configured with the glass substrate 42 inside the liquid crystal unit 80 interposed therebetween. According to this modification, the camera module 2 can realize a function for obtaining a high-quality image with a simple configuration suitable for downsizing and thinning.

  Although several embodiments of the present invention have been described, these embodiments are presented by way of example and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the scope of the invention. These embodiments and modifications thereof are included in the scope and gist of the invention, and are included in the invention described in the claims and the equivalents thereof.

  2 camera module, 10 solid-state imaging device, 11 front lens, 12, 80 liquid crystal unit, 13 rear lens, 14 pixel unit, 15 imaging processing circuit, 16 control unit, 17 angular velocity sensor, 31 OIS, 32 apodizer, 33 AF unit, 34, 35, 36, 61 Liquid crystal element, 41, 42, 43, 44 Glass substrate, 45, 53, 65 First conductive film, 46, 54, 66 Second conductive film, 47, 62, 64 Dielectric layer.

Claims (5)

An imaging optical system that captures light from the subject and forms a subject image;
A pixel unit that captures the subject image;
A diaphragm mechanism for adjusting the amount of light captured by the imaging optical system and traveling to the pixel unit;
A camera shake correction unit that performs camera shake correction of the subject image;
A focus adjustment unit that performs focus adjustment of the imaging optical system,
The aperture mechanism unit includes a light modulation element that can adjust the amount of light to pass according to the applied voltage,
The camera shake correction unit includes a liquid crystal element that can adjust the amount of refraction of incident light according to the distribution of voltage,
The focus adjustment unit includes a liquid crystal element that can adjust the amount of refraction of incident light according to an applied voltage,
The camera module, wherein the diaphragm mechanism unit, the camera shake correction unit, and the focus adjustment unit are integrally configured with a support substrate through which light is transmitted. An imaging optical system that captures light from the subject and forms a subject image;
A pixel unit that captures the subject image;
A diaphragm mechanism for adjusting the amount of light captured by the imaging optical system and traveling to the pixel unit;
A camera shake correction unit that performs camera shake correction of the subject image,
The aperture mechanism unit includes a light modulation element that can adjust the amount of light to pass according to the applied voltage,
The camera shake correction unit includes a liquid crystal element that can adjust the amount of refraction of incident light according to the distribution of voltage,
2. The camera module according to claim 1, wherein the aperture mechanism unit and the camera shake correction unit are integrally formed with a support substrate that transmits light interposed therebetween.   The camera module according to claim 2, wherein the aperture mechanism unit includes a liquid crystal element as the light modulation element. The image stabilization unit is
A transparent electrode for applying a voltage to the liquid crystal element;
A dielectric layer provided with the liquid crystal element between the transparent electrodes,
The camera module according to claim 2, wherein a surface of the dielectric layer on the liquid crystal element side is an inclined surface that is inclined with respect to an electrode surface of the transparent electrode. The camera shake correction unit includes a transparent electrode for applying a voltage to the liquid crystal element,
The camera module according to claim 2, wherein a plurality of voltages are applied to the transparent electrode, and a voltage distribution is generated by making each voltage different.

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