JP5650055B2 - Imaging device - Google Patents

Description

  The present invention relates to an imaging apparatus, and more particularly to a technique for simultaneously acquiring images of various image quality.

  In general, an imaging lens is designed so that various aberrations can be corrected as much as possible and a sharper image can be taken. On the other hand, there are times when you want to shoot with the effect of soft depiction. When such shooting is performed, it is known to use a soft focus lens or a soft focus filter.

  A soft focus lens is a lens that obtains a soft focus effect by appropriately leaving aberrations such as spherical aberration, thereby creating a soft-feeling blur around a sharp image. The soft focus filter is an optical filter that is attached to the front surface of the lens and reduces the sharpness of the image combined by the imaging lens, thereby producing a soft depiction effect.

  However, when using a soft focus lens, it is necessary to replace the normal lens with a soft focus lens. Also, when a soft focus filter is used, it is necessary to attach a filter.

  Therefore, a photo opportunity may be missed while changing lenses or attaching a filter. Also, the soft focus lens cannot be used for a compact camera in which the lens cannot be exchanged. In general, a compact camera is not provided with a filter mounting portion, and a soft focus filter cannot be mounted.

  In order to solve such a problem, Patent Document 1 discloses that one soft focus is formed for an optical system of a normal photographing lens in which a first lens unit having a positive refractive power and a second lens group having a positive refractive power are arranged in front and back. A soft focus lens in which the spherical aberration of the entire optical system is set to be equal to or less than a predetermined aberration in the aperture region that is three times or more of the open F value and is equal to or greater than the predetermined aberration when opened by adding or replacing the lens. Is disclosed.

  According to this technique, the spherical aberration becomes extremely small in the stop area that is three times or more of the open F value, and the spherical aberration in the open state suddenly shifts from the vicinity of a certain image height to the under side. You can switch between drawing and soft drawing.

  In Patent Document 2, a transparent electrode is formed with a light control layer in which nematic liquid crystal having positive dielectric anisotropy and a polymer having substantially the same refractive index as that of ordinary light are dispersed and oriented. There is disclosed a variable soft focus filter that is sandwiched between a pair of transparent substrates to form a liquid crystal element and applies a voltage to the liquid crystal element to provide a soft focus effect.

  According to this technology, a diffusion state can be realized only when necessary, and a transparent state can be achieved during normal use, so that sharp depiction and soft depiction can be switched instantaneously.

JP 2004-301883 A JP 10-48589 A

  However, even the techniques of Patent Documents 1 and 2 cannot simultaneously capture a sharp image and a soft focus image. Therefore, in order to capture both images, it is necessary to capture in time division.

  In addition to the soft focus, there is a problem that a plurality of images having different special effects cannot be taken simultaneously.

  The present invention has been made in view of such circumstances, and an object thereof is to provide an imaging apparatus that can simultaneously acquire images having a plurality of different spatial frequency characteristics and cross filter characteristics.

In order to achieve the above object, an imaging apparatus according to the present invention is an imaging optical system including an imaging lens, and includes an imaging optical system having different spatial frequency characteristics for each region through which incident light passes, and a light receiving element. A plurality of light receiving portions and a plurality of light receiving elements provided corresponding to each of the plurality of light receiving elements, and a plurality of light receiving elements respectively receiving subject light that has passed through a predetermined pupil region in the exit pupil of the imaging lens. An optical element; and an image generation unit configured to generate an image of a subject from the imaging signals of the plurality of light receiving elements, wherein the plurality of first optical elements of the plurality of optical elements are the first of the imaging lenses. Subject light that passes through the first pupil region of the exit pupil and the region having the spatial frequency characteristic of the light is incident on a corresponding light receiving element, and a plurality of second optical elements of the plurality of optical elements are Les The subject light that passes through the second pupil region in the region and the exit pupil having a second spatial frequency characteristics of the figure, is incident to the corresponding light receiving element, each of the plurality of optical elements, a pupil region said predetermined A prism element that causes a corresponding light receiving element to receive the subject light that has passed through the liquid crystal element, wherein a prism interface is formed at the liquid interface between the first liquid and the second liquid having different refractive indexes, The imaging apparatus further includes a control unit that controls the direction of the light beam received by the light receiving element corresponding to each of the plurality of prism elements by controlling the inclination of the prism interface with respect to the optical axis of the imaging lens. It is characterized by that.
In order to achieve the above object, an imaging apparatus according to the present invention is an imaging optical system including an imaging lens, and includes an imaging optical system having different spatial frequency characteristics for each region through which incident light passes, and a light receiving element. A plurality of light receiving portions and a plurality of light receiving elements provided corresponding to each of the plurality of light receiving elements, and a plurality of light receiving elements respectively receiving subject light that has passed through a predetermined pupil region in the exit pupil of the imaging lens. An optical element; and an image generation unit configured to generate an image of a subject from the imaging signals of the plurality of light receiving elements, wherein the plurality of first optical elements of the plurality of optical elements are the first of the imaging lenses. Subject light that passes through the first pupil region of the exit pupil and the region having the spatial frequency characteristic of the light is incident on a corresponding light receiving element, and a plurality of second optical elements of the plurality of optical elements are Les The subject light passing through the second pupil region in the exit pupil and the region having the second spatial frequency characteristic is incident on the corresponding light receiving element, and the imaging optical system is a distance from the center of the imaging lens. The spatial frequency is different for each of the circular region and the annular region divided by the above, and the plurality of optical elements are light-shielding elements that form an annular opening and a microlens having different focal lengths. And

  According to the present invention, images having a plurality of different spatial frequency characteristics can be acquired as image data separated simultaneously and independently. As a result, it is possible to perform synchronous shooting and moving image shooting, which has been impossible in the past.

  The image generating unit selects which pupil region of the exit pupil should generate the subject image based on the subject light that has passed through, and captures a plurality of light receiving elements that receive the subject light that has passed through the selected pupil region It is preferable to generate an image of the subject using a signal.

  Thereby, various images suitable for the subject can be generated.

  Each of the plurality of optical elements may be a prism element that causes a corresponding light receiving element to receive subject light that has passed through the predetermined pupil region.

  As a result, the subject light that has passed through an appropriately predetermined pupil region can be received by the corresponding light receiving element.

  The prism element is a liquid prism element in which a prism interface is formed at a liquid interface between a first liquid and a second liquid having different refractive indexes, and the imaging device is configured to perform the operation with respect to the optical axis of the imaging lens. It is preferable to further include a control unit that controls the direction of the light beam received by the light receiving element corresponding to each of the plurality of prism elements by controlling the inclination of the prism interface.

  Thereby, the spatial frequency characteristic corresponding to a light receiving element can be switched at high speed.

  A prism housing that holds the first liquid and the second liquid, a first region that is filled with the first liquid along the optical axis, and a second liquid that is filled with the second liquid. A partition plate that is divided into two regions, and a plurality of through holes are formed in the partition plate corresponding to positions where the plurality of liquid prism elements are formed, By controlling the position of the liquid interface at the first side surface portion of each of the through holes and the position of the liquid interface at the second side surface portion facing the first side surface portion, the inclination of the prism interface with respect to the optical axis is controlled. It is preferable to control.

  Thereby, the inclination of the prism interface can be appropriately controlled.

  The control unit, when causing the light receiving element to receive subject light that has passed through a pupil region including the optical axis in the exit pupil, causes the liquid interface to be substantially orthogonal to the optical axis, and When the subject light that has passed through the pupil region not including the optical axis is received by the light receiving element, the liquid interface may be inclined with respect to the optical axis.

  Thereby, the light received by the light receiving element can be appropriately switched.

  The control unit, when causing the light receiving element to receive subject light that has passed through a pupil region that does not include the optical axis in the exit pupil, tilts the liquid interface with respect to the optical axis to a first inclination, When subject light that has passed through another pupil region not including the optical axis in the exit pupil is received by the light receiving element, the liquid interface may be inclined with respect to the optical axis to a second inclination.

  Thereby, the light received by the light receiving element can be appropriately switched.

  At least one of the plurality of through holes has the first side surface portion and the second side surface portion having different thicknesses, and the control unit includes the first side surface portion and the second side surface portion. The liquid interface with respect to the optical axis is switched to a different inclination by switching between a state in which the region surrounded by the first liquid is filled and a state in which the region is filled with the second liquid. The imaging apparatus according to any one of claims 5 to 7, wherein

  Thereby, the light received by the light receiving element can be appropriately switched.

  The plurality of light receiving elements are arranged in a matrix, and the partition plate is formed by alternately providing first partition portions extending in the column direction and second partition portions extending in the column direction in the row direction. The first partition portion has side portions having a first thickness along the optical axis direction on both sides, and the second partition portion has a second thickness along the optical axis direction. The plurality of through holes are formed by a side surface portion of the first partition portion and a side surface portion of the second partition portion adjacent to the first partition portion, respectively. The first liquid side of the partition part and the second partition part forms substantially the same plane, and the control part is configured to make the inclination of the liquid interface with respect to the optical axis different from each other in the row direction. And a state where the first liquid is filled in a region surrounded by the second side surface portion and the second side surface portion. It is preferred.

  Thereby, the inclination of the prism interface can be appropriately controlled.

  The control unit may control an inclination of the interface with respect to the optical axis by controlling an internal pressure of a region holding the first liquid.

  Thereby, the inclination of the prism interface can be appropriately controlled.

  Each of the plurality of optical elements is provided with a micro optical system in which an optical axis is deviated from a light receiving opening of the light receiving element so that subject light passing through the predetermined pupil region is received by the corresponding light receiving element. It may be a lens.

  As a result, the subject light that has passed through an appropriately predetermined pupil region can be received by the corresponding light receiving element.

  Each of the plurality of optical elements may be a light shielding element in which an opening having directivity to the predetermined pupil region is formed with respect to a corresponding light receiving element.

  As a result, the subject light that has passed through an appropriately predetermined pupil region can be received by the corresponding light receiving element.

  The plurality of optical elements are provided corresponding to the first polarization filters that transmit different polarization components in the plurality of pupil regions, respectively, and the second polarization that respectively transmits the different polarization components. You may have a filter.

  As a result, the subject light that has passed through an appropriately predetermined pupil region can be received by the corresponding light receiving element.

  The plurality of optical elements include a first wavelength filter that transmits different wavelength components in the plurality of pupil regions, and a second wavelength filter that is provided corresponding to the plurality of light receiving elements and transmits the different wavelength components, respectively. You may have two or more.

  As a result, the subject light that has passed through an appropriately predetermined pupil region can be received by the corresponding light receiving element.

  Each optical element of the plurality of optical elements is a microlens provided for each of a plurality of light receiving element units, and includes a region having a first spatial frequency characteristic of the imaging lens and a first pupil region in the exit pupil. Subject light passing through is incident on the first light receiving element, and subject light passing through the second pupil region of the exit pupil and the region having the second spatial frequency characteristic of the imaging lens is incident on the second light receiving element. You may let them.

  As a result, the subject light that has passed through an appropriately predetermined pupil region can be received by the corresponding light receiving element.

  The imaging optical system has a spatial frequency different for each of a circular region and an annular region divided by a distance from the center of the imaging lens, and the plurality of optical elements are microlenses having different focal lengths, It may be a light shielding element that forms an annular opening.

  As a result, the subject light that has passed through an appropriately predetermined pupil region can be received by the corresponding light receiving element.

  In the imaging optical system, it is preferable that the imaging lens has different spatial frequency characteristics for each region.

  Thereby, it is possible to generate a blurred image suitable for the subject.

  The imaging optical system may include an optical filter having different spatial frequency characteristics for each region.

  Thereby, it is possible to generate a blurred image suitable for the subject.

  In order to achieve the above object, an imaging apparatus according to the present invention is an imaging optical system including an imaging lens, and includes an imaging optical system having different cross filter characteristics for each region through which incident light passes, and a light receiving element. A plurality of light receiving portions and a plurality of light receiving elements provided corresponding to each of the plurality of light receiving elements, and a plurality of light receiving elements respectively receiving subject light that has passed through a predetermined pupil region in the exit pupil of the imaging lens. An optical element and an image generation unit that generates an image of a subject from imaging signals of the plurality of light receiving elements, and a plurality of first optical elements of the plurality of optical elements are the first of the imaging lenses Subject light passing through the first pupil region in the region having the cross filter characteristic and the exit pupil is incident on a corresponding light receiving element, and a plurality of second optical elements among the plurality of optical elements are The subject light that passes through the second pupil region in the region and the exit pupil having a second cross filter characteristics of the image lens is characterized in that so that it is incident on the corresponding light receiving element.

  According to the present invention, images having a plurality of different cross filter characteristics can be acquired as image data separated simultaneously and independently. As a result, it is possible to perform synchronous shooting and moving image shooting, which has been impossible in the past.

  According to the present invention, images having a plurality of different spatial frequency characteristics and cross filter characteristics can be acquired simultaneously and independently as image data. As a result, it is possible to perform synchronous shooting and moving image shooting, which has been impossible in the past.

1 is a diagram schematically illustrating an example of a block configuration of an imaging apparatus 10. FIG. FIG. 3 is a diagram schematically illustrating an example of the configuration of a deflection unit 140, a micro lens unit 150, and a light receiving unit 160. It is a figure which shows the schematic cross section which cut | disconnected the deflection | deviation part 140 by the surface perpendicular | vertical to an optical axis. It is a figure which shows typically an example of the process which produces | generates the synthesized image 550 in which the depth of field was expanded. It is a figure which shows typically another example of a structure of the deflection | deviation part. It is a figure which shows the modification of the partition plate. It is a figure which shows typically an example of the light-receiving unit provided with another deflection | deviation optical element. It is a figure which shows typically an example of the light-receiving unit provided with another deflection | deviation optical element. It is a figure which shows typically an example of the light-receiving unit provided with another deflection | deviation optical element. FIG. 20 is a diagram illustrating an example of another block configuration of the imaging apparatus 1010. It is a mimetic diagram showing an example of micro lens 152a and a plurality of light receiving elements 1162a provided corresponding to micro lens 152a. FIG. 10 is a schematic diagram illustrating an enlarged light receiving unit of the imaging apparatus 1010. FIG. 25 is a diagram illustrating an example of another block configuration of the imaging apparatus 1110. FIG. 20 is a diagram illustrating a modification of the imaging device 1110. It is a figure which shows typically another example of a lens system. The figure which shows typically an example of the block configuration of the imaging device 1210 The perspective view which shows the shape of a shading mask A bird's-eye view schematically showing the lens system, microlens, shading mask, and light-receiving element A diagram schematically showing an example of a light receiving unit A diagram schematically showing an example of a light receiving unit The figure which shows the relationship between the light which injected into the micro lens, and the light which a light receiving element receives The figure which shows the relationship between the light which injected into the micro lens, and the light which a light receiving element receives The figure which shows the relationship between the light which injected into the micro lens, and the light which a light receiving element receives It is the figure which showed typically a mode that the light which injected into the lens was isolate | separated and taken out as an image signal.

  Hereinafter, the present invention will be described through embodiments of the invention, but the following embodiments do not limit the invention according to the claims. In addition, not all the combinations of features described in the embodiments are essential for the solving means of the invention.

  FIG. 1 schematically illustrates an example of a block configuration of the imaging apparatus 10. The imaging device 10 according to the present embodiment provides a function of capturing images having different spatial frequency characteristics (blur). In particular, the optical configuration according to the imaging apparatus 10 provides an imaging apparatus that can mount the function in a compact manner using a fixed imaging lens (imaging lens). The imaging apparatus 10 includes a lens system 100, a light receiving unit 20, an image generation unit 170, a control unit 180, and an image recording unit 190. The light receiving unit 20 includes an optical device 115 and a light receiving unit 160.

  The lens system 100 is a single imaging lens system. The lens system 100 includes one or more lenses 110. The subject light that has passed through the lens system 100 passes through the optical device 115 and is received by the light receiving unit 160.

  The lens system 100 is a lens system having different MTF (Modulation Transfer Function) characteristics for each region through which incident light passes. For example, the lens system 100 may include a lens system 100a having different MTF characteristics for each region. In this figure, in order to illustrate the difference in MTF characteristics in an easy-to-understand manner, it is assumed that the objective-side optical surface of the lens 110a gives different MTF characteristics for each region. The lens system 100 only needs to have an optical path that gives different MTF characteristics in the entire lens system, and a difference in MTF characteristics may not be provided by a specific optical surface of a specific lens.

  The optical device 115 causes light on the light receiving unit 160 to receive light that has passed through the pupil region 122a of the exit pupil 120 of the lens system 100, light that has passed through the pupil region 122b, and light that has passed through the pupil region 122c. The light receiving unit 160 supplies a signal based on the light received in the different areas to the image generation unit 170 as an image signal. The image generation unit 170 generates an image with a different blur from the image signal. The image recording unit 190 records the image generated by the image generation unit 170. The image recording unit 190 may record the image in a nonvolatile memory. The non-volatile memory may be included in the image recording unit 190. Further, the nonvolatile memory may be an external memory that is detachably provided to the imaging device 10. The image recording unit 190 may output an image outside the imaging apparatus 10.

  The optical device 115 includes a deflection unit 140 and a microlens unit 150. The deflecting unit 140 includes a plurality of prism elements 142a to 142c as examples of deflecting optical elements. The microlens unit 150 includes a plurality of microlenses 152a to 152c. The light receiving unit 160 includes a plurality of light receiving elements 162a to 162c. In this figure, for ease of explanation, three light receiving elements 162a to 162c, three micro lenses 152a to 152c, and three prism elements 142a to 142c are illustrated. It does not indicate that each has only three. Needless to say, each optical element has an arbitrary number for imaging a subject. The plurality of microlenses 152 a to 152 c may be collectively referred to as the microlens 152 or the plurality of microlenses 152. The plurality of light receiving elements 162a to 162c may be collectively referred to as the light receiving element 162 or the plurality of light receiving elements 162. Similarly, other optical elements may be collectively referred to as optical elements by omitting the subscripts.

  The plurality of light receiving elements 162 may form a MOS type image pickup element. The plurality of light receiving elements 162 may form a solid-state imaging element such as a CCD type imaging element in addition to a MOS type imaging element.

  The microlens 152 is provided corresponding to each of the plurality of light receiving elements 162. The plurality of microlenses 152 re-image the subject light imaged by the lens system 100 and cause the corresponding light receiving elements 162 to receive the light. The illustrated microlenses 152a to 152c are provided corresponding to the light receiving elements 162a to 162c, respectively. The micro lens 152a re-images the subject light imaged by the lens system 100 and causes the light receiving element 162a to receive the light. Similarly, the micro lenses 152b and c re-image the subject light imaged by the lens system 100 and cause the light receiving elements 162b and c to receive the light, respectively. The microlens 152 limits the size of the exit pupil 120 through which the light flux to each of the light receiving elements 162 passes. For example, the microlens 152 has a refractive power large enough to cause each light receiving element 162 to receive light that has passed through a partial region of the exit pupil 120. For example, the microlens 152 can have a refractive power that causes each light receiving element 162 to receive light that has passed through a region having an area of ¼ or less of the exit pupil 120.

  The prism elements 142 are provided corresponding to the plurality of light receiving elements 162. The prism element 142, the micro lens 152, and the light receiving element 162 are provided in a one-to-one correspondence with each other. For example, the prism element 142a is provided corresponding to the microlens 152a and the light receiving element 162a. A set of optical elements corresponding to each other among the prism element 142, the microlens 152, and the light receiving element 162 is distinguished by subscripts a to c.

  The prism element 142 is an example of an optical element that causes a corresponding light receiving element 162 to receive subject light that has passed through a predetermined pupil region 122. Specifically, the prism element 142a causes the light receiving element 162a to receive the subject light 130a that has passed through the pupil region 122a in the exit pupil 120 of the lens system 100 via the microlens 152a. The prism element 142b causes the light receiving element 162b to receive the subject light 130b that has passed through the pupil region 122b of the exit pupil 120 of the lens system 100 via the microlens 152b. On the other hand, the prism element 142c causes the light receiving element 162c to receive the subject light 130c that has passed through the pupil region 122c in the exit pupil 120 of the lens system 100 via the microlens 152c.

  Specifically, the prism elements 142a to 142c have prism angles that cause the light receiving elements 162a to 162c to receive the subject lights 130a to 130c that have passed through the pupil regions 122a to 122c, respectively. Subject light 130a passing through the pupil region 122a and entering the light receiving element 162a, subject light 130b passing through the pupil region 122b and entering the light receiving element 162b, and subject light 130c passing through the pupil region 122c and entering the light receiving element 162c are The lens 110a passes through different optical surfaces. For this reason, the light receiving elements 162a to 162c receive light that has passed through regions of the lens system 100 having different MTF characteristics.

  As described above, the prism element 142 causes the corresponding light receiving element 162 among the plurality of light receiving elements 162 to receive the subject light that has passed through the predetermined pupil region 122 in the exit pupil 120 of the lens 110. Specifically, the plurality of first prism elements including the prism element 142a among the plurality of prism elements 142 correspond to the light receiving element corresponding to the subject light passing through the region having the first MTF characteristic of the lens 110 and the pupil region 122a. 162 is incident. The plurality of second prism elements including the prism element 142b among the plurality of prism elements 142 are configured to receive subject light passing through the pupil region 122b of the exit 110 and the region having the second MTF characteristic of the lens 110, and corresponding light receiving elements 162. To enter. A plurality of third prism elements including the prism element 142c among the plurality of prism elements 142 cause subject light passing through the region having the third MTF characteristic of the lens 110 and the pupil region 122c to enter the corresponding light receiving element 162.

  The light receiving element 162 outputs an imaging signal having an intensity corresponding to the amount of received light to the image generation unit 170. The image generation unit 170 generates an image of the subject from the imaging signals of the plurality of light receiving elements 162. Specifically, the image generation unit 170 generates an image signal indicating an image with a different blur from the imaging signal supplied from the light receiving element 162. In this example, light that can be received by the light receiving elements 162a to 162c is limited to light that has passed through the pupil regions 122a to 122c, respectively. Therefore, the image generation unit 170 generates a first blur image signal from the imaging signals of some of the light receiving elements 162 that receive the light that has passed through the pupil region 122a. Further, the image generation unit 170 generates a second blur image signal from the imaging signals of a part of the light receiving elements 162 that receive the light that has passed through the pupil region 122b. In addition, the image generation unit 170 generates a third blur image signal from the imaging signals of some light receiving elements 162 that receive the light that has passed through the pupil region 122c. Note that these image signals may be referred to as a first blur image, a second blur image, and a third blur image, respectively, using the blur.

  The image generation unit 170 may generate one image by combining images with different blurring. For example, a clear image without blur is generated for the main subject, and one image is generated with an image other than the main subject having a large blur. As described above, the imaging apparatus 10 can generate images of various expressions by generating one image by combining images with different blurring. Note that the image generation unit 170 may generate different blurred images as separate images. Thus, according to the optical device 115, images with different blurring can be obtained in one shot using the single lens system 100. In addition, since the lens system 100 is not driven, a compact imaging device can be provided.

  The imaging device 10 may be an imaging device such as a mobile phone with a camera function or a digital camera. In addition, you may provide the functional block of the image generation part 170 of the lens system 100, the optical apparatus 115, and the light-receiving part 160, and the control part 180 as an imaging device for imaging devices. For example, the imaging device may be an imaging module incorporated in an imaging device.

  In this figure, the pupil of the exit pupil 120 is shown for the purpose of easily showing that the light receiving element 162 receives light that has passed through a specific partial region of the exit pupil 120 by the action of the microlens 152. Regions 122a-c are shown in white. Areas other than the pupil areas 122a to 122c are indicated by hatching. This does not indicate that subject light does not pass through regions other than the pupil regions 122a to 122c.

  The control unit 180 controls the direction in which the deflection unit 140 deflects the subject light. For example, the control unit 180 controls the prism angle of the prism element 142. By controlling the direction of deflection by the deflecting unit 140 by the control unit 180, for example, it is possible to control which light receiving element receives light passing through which pupil region. Specific control contents by the control unit 180 will be described later.

  FIG. 2 schematically shows an example of the configuration of the deflection unit 140, the microlens unit 150, and the light receiving unit 160. In this example, the plurality of prism elements 142 included in the deflecting unit 140 are liquid prism elements formed at liquid interfaces having different refractive indexes. The prism angle of the prism element 142 is determined by the angle of the liquid interface.

  The deflection unit 140 includes a housing 200 that holds the first liquid and the second liquid, a partition plate 242, and a drive unit 290. The partition plate 242 divides the interior of the housing 200 into a first liquid region 210 filled with the first liquid and a second liquid region 220 filled with the second liquid along the optical axis of the lens system 100. The first liquid and the second liquid have a refractive index different from each other and do not mix with each other in a contact state like water and oil. Examples of the combination of the first liquid and the second liquid include PDMS (Poly-Dimethyl-Siloxane) and pure water. Here, it is assumed that the refractive index of the first liquid is larger than the refractive index of the second liquid. Moreover, it is preferable that the density of each of the first liquid and the second liquid is substantially equal.

  A plurality of through holes 250a to 250d are formed in the partition plate 242 corresponding to positions where the plurality of prism elements 142a to 142d are formed. The prism elements 142a to 142c illustrated in FIG. 1 are formed at positions where the through holes 250a to 250c are formed, respectively. The shape of the through-hole 250 viewed from the object-side surface or the image-side surface of the housing 200 may be a square, a rectangle, a trapezoid, a circle, an ellipse, or the like, and may be various other shapes.

  On the object-side surface and the image-side surface of the housing 200, a light-transmitting portion made of a light-transmitting material such as glass is formed. The light transmitting part is formed at a position corresponding to the through hole 250, the micro lens 152, and the light receiving element 162, and the subject light is formed on the light transmitting part, the through hole 250, and the image side surface formed on the object side surface. Then, the light passes through the transparent portion and enters the corresponding microlens 152. Note that the object side surface and the entire image side surface of the housing 200 may be formed of a transparent material such as glass.

  Partition plate 242 includes partition portions 240-1 to 240-5. The through hole 250 is formed in a space between the opposing partitioning portions 240. The partition part 240 does not contact the first liquid and the second liquid. The first liquid and the second liquid come into contact with each other in the through hole 250 to form an interface that becomes the prism element 142.

  The through hole 250a has a side part 252a (corresponding to the first side part) and a side part 254a (corresponding to the second side part). The side surface portion 252a and the side surface portion 254a are side surface portions that face the partition portion 240-1 and the partition portion 240-2, respectively. The side surface portion 252a has a first thickness along the optical axis direction of the lens system 100, and the side surface portion 254a has a second thickness along the optical axis direction of the lens system 100. That is, the through hole 250a is formed so as to be surrounded by side surfaces including the side surface portion 252a and the side surface portion 254a of the partition plate 242 having different thicknesses. For example, when the through hole 250a has a rectangular opening, the through hole 250a is surrounded and formed by the side surface portion 252a, the side surface portion 254a, and the two side surface portions that couple the side surface portion 252a and the side surface portion 254a. . Here, it is assumed that the second thickness is larger than the first thickness.

  The through hole 250b has a side part 252b and a side part 254b. The side surface portion 252b and the side surface portion 254b are side surface portions that face the partition portion 240-2 and the partition portion 240-3, respectively. The side surface portion 252b has a second thickness along the optical axis direction of the lens system 100, and the side surface portion 254b has a third thickness along the optical axis direction of the lens system 100. The third thickness is assumed to be larger than the first thickness and smaller than the second thickness. Unlike the through-hole 250a, the through-hole 250b has a side surface portion 252b having a first thickness and a side surface portion 254b having a third thickness in order in the direction in which the plurality of through-holes 250 are arranged. Since other points are the same as those of the through hole 250a, description thereof is omitted.

  The through hole 250c has a side part 252c and a side part 254c. The side surface portion 252c and the side surface portion 254c are side surface portions that face the partition portion 240-3 and the partition portion 240-4, respectively. The through hole 250c is formed by a side surface portion 252c having a third thickness and a side surface portion 254c having a fourth thickness. The fourth thickness is assumed to be smaller than the first thickness. Here, it is assumed that the difference between the second thickness and the third thickness is different from the difference between the third thickness and the fourth thickness.

  The through hole 250d has the same shape as the through hole 250a. The through hole 250d is formed by a side surface portion 252d having a first thickness and a side surface portion 254d having a second thickness. The side part 252d and the side part 254d are provided by the partition part 240-4 and the partition part 240-5, respectively. The partition portion 240-4 has a side surface portion 254c having a fourth thickness on one side and a side surface portion 252d having a first thickness on the other side. Although only the through-hole 250d is illustrated in this example, the partition plate 242 is formed with a through-hole 250a, a through-hole 250b, and a through-hole 250c that are repeated in this order at equal intervals in a row.

  When the pressure of the first liquid filled in the first liquid region 210 is set to a specific pressure, a planar interface is formed so that the pressure difference of the liquid and the surface tension are balanced according to the pressure. When the pressure of the first liquid is set to the first pressure so as to be in a balanced state in the state where each second through hole 250 is filled with the second liquid, a liquid interface indicated by a broken line in this figure is formed like the prism element 282. The Specifically, in each through-hole 250, the liquid interface is supported by the end portion of the side surface portion 252 on the first liquid region 210 side and the end portion of the side surface portion 254 on the first liquid region 210 side. The partition plate 242 has a substantially planar end surface on the first liquid side. That is, the first liquid side of each partition 240 forms substantially the same plane. Since the end face is parallel to the image side of the housing 200, the liquid interface indicated by a broken line has substantially no prism effect.

  On the other hand, when the pressure of the first liquid is raised from the first pressure to the second pressure so as to be balanced in the state where the first liquid is filled in each through hole 250, the position of the liquid interface is the second liquid. The liquid interface shown by the solid line in this figure is formed like the prism element 281. For example, in each through-hole 250, the liquid interface is carried on the end portion of the side surface portion 252 on the second liquid region 220 side and the end portion of the side surface portion 254 on the second liquid region 220 side. The inclination of this liquid interface becomes an inclination according to the thickness of the side part which forms each through-hole 250. FIG. Therefore, in this state, a prism row is formed in which prisms having prism angles of three different angles are sequentially formed.

  The configuration of the microlens unit 150 and the light receiving unit 160 will be described. The plurality of microlenses 152 are provided on the transparent substrate corresponding to the plurality of through holes 250. The light receiving unit 160 includes a plurality of color filters 260, a light shielding unit 262, and a plurality of light receiving elements 162. The plurality of color filters 260 and the plurality of light receiving elements 162 are provided corresponding to the through holes 250. That is, the microlens 152, the color filter 260, and the light receiving element 162 are respectively provided corresponding to the plurality of through holes 250.

  The color filter 260 selectively transmits light in a predetermined wavelength region out of subject light that has passed through the corresponding through hole 250 and the micro lens 152 and causes the corresponding light receiving elements 162 to receive the light. The color filter 260 may be one of a color filter that transmits light in the wavelength range belonging to red, a color filter that transmits light in the wavelength range that belongs to green, and a color filter that transmits light in the wavelength range that belongs to blue. . The color filter 260 is arranged on the light receiving element 162 in a predetermined pattern in order to capture a color image.

  In the light shielding unit 262, openings 264 that define the light receiving openings of the plurality of light receiving elements 162 are formed at positions corresponding to the plurality of light receiving elements 162 in order to prevent interference with adjacent pixels. Subject light travels to the light receiving element 162 through the through hole 250, the microlens 152, and the color filter 260. The plurality of light receiving elements 162 respectively receive light that has passed through the corresponding openings 264, and generate voltage signals that form imaging signals by photoelectric conversion.

  In the state in which the liquid interface indicated by the broken line in the figure is formed, the liquid interface does not have a prism effect. For this reason, in this state, the light receiving element 162 receives light that has passed through a region of the exit pupil 120 centered on the optical axis. Therefore, the image formed by the plurality of light receiving elements 162 is a blurred image based on the MTF characteristic of the region near the optical axis of the lens system 100. In this case, although shooting is performed with one MTF characteristic, a high-resolution image can be obtained.

  In the state in which the liquid interface shown by the solid line in this drawing is formed, liquid interfaces having different prism angles are formed in the through holes 250a to 250c. Therefore, in this state, the directions of the light beams received by the light receiving elements 162a to 162c are directed to different pupil regions 122 of the exit pupil 120. Here, the liquid interface formed in the through hole 250a, the liquid interface formed in the through hole 250b, and the liquid interface formed in the through hole 250c are respectively the prism element 142a, the prism element 142b, and the prism element illustrated in FIG. 142c is formed. In this state, a plurality of blur images based on a plurality of MTF characteristics can be obtained.

  As described above, the prism element 142 is a liquid prism element in which a prism interface is formed at the liquid interface between the first liquid and the second liquid having different refractive indexes. The control unit 180 controls the inclination of the prism interface with respect to the optical axis of the lens system 100 in order to control the direction of the light beam received by the light receiving element 162 corresponding to each of the plurality of prism elements 142. Specifically, the control unit 180 controls the position of the liquid interface in the side surface part 252 of the through-hole 250 and the position of the liquid interface in the side surface part 254 facing the side surface part 252, thereby tilting the prism interface with respect to the optical axis. To control.

  For example, the control unit 180 controls the pressure of the first liquid by controlling the pressure in the liquid region 230 that communicates with the first liquid region 210. Specifically, the housing 200 has an elastic surface 280 that contacts the first liquid in the liquid region 230. In addition, the deflecting unit 140 includes a driving unit 290 that displaces the elastic surface 280 to control the volume of the liquid region 230. The driving unit 290 can include a piezoelectric element. The piezoelectric element may be a piezo element. The control unit 180 controls the voltage applied to the piezoelectric element to change the shape of the piezoelectric element, thereby displacing the tip part contacting the elastic surface 280 in the left-right direction on the paper surface.

  When the control unit 180 moves the interface between the first liquid and the second liquid in the object side direction along the side surface of the through hole 250, the tip of the driving unit 290 decreases in the direction in which the volume of the liquid region 230 decreases. Displace the part. As a result, the internal pressure of the first liquid increases, and the liquid interface moves in the direction of the object side. When the liquid interface is moved in the image side direction along the side surface of the through-hole 250, the controller 180 displaces the tip of the drive unit 290 in the direction in which the volume of the liquid region 230 increases. As a result, the internal pressure of the first liquid decreases, and the liquid interface moves in the direction of the image side.

  As in the deflection unit 140 of this example, the control unit 180 controls the internal pressure of the liquid region 210, so that the position of the liquid interface at the side surface 252 of the through hole 250 and the side surface 254 facing the side surface 252. The position of the liquid interface is controlled, and therefore the inclination of the liquid interface with respect to the optical axis is controlled. That is, the control unit 180 can control the inclination of the prism element 142 by controlling the internal pressure of the liquid region 210. In particular, as in the partition plate 242 of this example, the state in which the control unit 180 is filled with the first liquid in the region surrounded by the both side surfaces of the partitioning portion 240, and the state in which the second liquid is filled in the region. By switching between these, the liquid interface with respect to the optical axis is switched to a different inclination. According to the deflecting unit 140 of this example, when the light receiving element 162 receives the subject light 130 that has passed through the pupil region including the optical axis in the exit pupil 120, the control unit 180 substantially reduces the liquid interface with respect to the optical axis. When subject light 130 that is orthogonal and passes through the pupil region 122 that does not include the optical axis in the exit pupil 120 is received by the light receiving element 162, the liquid interface can be inclined with respect to the optical axis. Since the direction of the light beam received by the light receiving element 162 can be controlled at high speed by controlling the internal pressure of the liquid region 210, it is possible to switch between multi-MTF imaging and high-resolution imaging at high speed.

  FIG. 3 shows a schematic cross section of the deflecting unit 140 cut along a plane perpendicular to the optical axis. This figure illustrates a schematic cross section of the partition plate 242 of FIG. The subject light travels toward the paper surface, and the position of the light receiving element 162 is schematically shown by a broken line for reference. As illustrated, the partition plate 242 has through holes 250 formed in a matrix. The light receiving element 162 is also provided at a position corresponding to the through hole 250. That is, the through holes 250 and the plurality of light receiving elements 162 are arranged in a matrix. The through holes 250 and the light receiving elements 162 are provided at substantially equal intervals in the row direction 350 and the column direction 360.

  Specifically, the partition part 240-1, the partition part 240-2, the partition part 240-3, and the partition part 240-4 are members extending in the column direction 360. These rows are partitioned by a member extending in the row direction 350. Thereby, in addition to the through holes 250a to 250d, a plurality of columns of through holes arranged in the row direction 350 are formed. For example, a row of through holes arranged in the row direction 350 is formed in a row starting from the through hole 250a, a row starting from the through hole 250e, and a row starting from the through hole 250f.

  As described with reference to FIG. 2, the partition portion 240-1 has a side portion having a first thickness on the side portion along the optical axis direction of the lens system 100. Moreover, the partition part 240-2 has a side part of 2nd thickness in a both side part along the optical axis direction of the lens system 100. As shown in FIG. The partition portion 240-3 has side portions having a third thickness on both sides along the optical axis direction of the lens system 100. The partition portion 240-4 has a side surface portion having a fourth thickness and a side surface portion having a first thickness along the optical axis direction of the lens system 100. That is, the partition plate 242 has a partition portion that exhibits a difference in thickness between the opposing side surface portions. In addition, two or more types of partition portions are sequentially formed so that the thickness difference is different between adjacent through holes 250. Thus, the through holes 250 that provide different prism angles in the row direction 350 are sequentially arranged in a plurality of rows.

  In this figure, a partition plate 242 that forms three types of partition portions so as to simultaneously form prism angles having three types of inclinations is illustrated. When two or more types of prism angles are formed simultaneously, two types of partitioning portions may be formed alternately. That is, the first partition portion having side portions having a first thickness along both sides along the optical axis direction of the lens system 100 and the side portions having a second thickness along both sides along the optical axis direction. The through hole 250 may be formed by the second partition portion. Specifically, the through hole 250 is formed by a side surface portion of the first partition portion and a side surface portion of the second partition portion adjacent to the first partition portion. Then, the control unit 180 controls the state surrounded by the side portion of the partition unit 240 so that the first liquid is filled, whereby the inclination of the liquid interface with respect to the optical axis can be made different in the column direction 360. it can.

  Further, the through holes 250 a to 250 d communicate with each other through the liquid region 210. The liquid region 210 may be partitioned into a plurality of regions, but may not be partitioned. When the liquid region 210 is partitioned, a driving unit is provided corresponding to each of the partitioned liquid regions 210, and each driving unit controls the pressure of the first liquid in the corresponding liquid region 210. In the example of this figure, a drive unit 290, a drive unit 291 and a drive unit 292 are provided for each row. Thereby, compared with the case where the internal pressure of a 1st liquid area | region is controlled by one drive part, a prism element can be controlled rapidly. Even when the liquid region 210 is not partitioned into a plurality of regions and all through holes communicate with the liquid region 210, a plurality of drive units may be provided. That is, the internal pressure of the first liquid region 210 may be controlled by a plurality of driving units.

  FIG. 4 schematically shows an example of processing for generating the composite image 550. The first blur image 510, the second blur image 520, and the third blur image 530 are examples of different blur images generated by the image generation unit 170, and each of the first optical surface and the first optical surface having the first MTF characteristic. An image is obtained by light that has passed through the second optical surface having the 2MTF characteristic and the third optical surface having the third MTF characteristic.

  The first blurred image 510 includes subject images 512, 514, and 516. The second blurred image 520 includes subject images 522, 524, and 526. Similarly, the third blur image 530 includes subject images 532, 534, and 536.

  The subject images 512, 522, and 532 are subject images of the same subject, and each has a different blur. The subject images 514, 524, and 534 are subject images of the same subject, and are different in blur. Similarly, the subject images 516, 526, and 536 are subject images of the same subject, and each has a different blur.

  The image generation unit 170 generates a composite image 550 using these subject images. As a result, it is possible to generate a composite image 550 in which a bokeh suitable for each subject is selected. In the example of FIG. 4, the composite image 550 is generated using the subject image 512 of the first blur image 510, the subject image 524 of the second blur image 520, and the subject image 536 of the third blur image 530. . What blur image should be used for which subject may be configured so that the user can freely set the subject image. Further, the imaging device 10 may automatically determine.

  As described above, the image generation unit 170 selects which pupil region 122 of the exit pupil 120 should generate the subject image, and receives a plurality of subject lights that have passed through the selected pupil region 122. The image of the subject is generated using the imaging signal of the light receiving element 162. That is, the blur can be selected for each subject. At this time, the image generation unit 170 may select two or more pupil regions 122. That is, the image generation unit 170 selects at least one pupil region 122 through which the subject light imaged at the position of the light receiving unit 160 passes.

  FIG. 5 schematically shows another example of the configuration of the deflecting unit 140. The deflection unit 140 illustrated in FIG. 2 can capture images with light beams that pass through three different pupil regions of the exit pupil 120 in the first state, and pass through one pupil region of the exit pupil 120 in the second state. Images can be taken with a light beam. The deflecting unit 140 of this example has three states as the liquid interface state, and has a configuration capable of imaging with light beams that pass through three different pupil regions in each state. In particular, the surface shape of the partition plate 242 on the first liquid side and the second liquid side and the configuration of the side surface portion forming the through hole 250 are different from the partition plate 242 illustrated in FIG. Here, the difference will be mainly described.

  The through-hole 250a of this example is formed by a side surface portion 642a having a first thickness included in the partition portion 640-1 and a side surface portion 644a having a fourth thickness included in the partition portion 640-2. The fourth thickness is thicker than the second thickness. Further, in the through hole 250a of this example, the interface connecting the end points on the second liquid side of both side surfaces has the same prism angle as the interface formed on the second liquid side of the through hole 250a illustrated in FIG. Therefore, the prism element formed at the interface restricts the light received by the light receiving element 162a to the light that has passed through the pupil region 122a. As shown by the broken line in the figure, the interface connecting the end points on the first liquid side of both side surfaces in the through hole 250a of this example has a prism angle inclined from the plane perpendicular to the optical axis. The prism element 142a having the prism angle restricts the light received by the light receiving element 162a to the light passing through the pupil region between the vicinity of the optical axis and the pupil region 122c in the exit pupil 120.

  The through hole 250b in this example is formed by a fourth thickness side surface 642b included in the partition portion 640-2 and a fourth thickness side surface portion 644b included in the partition portion 640-3. The partition part 640-2 and the partition part 640-3 are located at the same position in the optical axis direction. For this reason, an interface perpendicular to the optical axis is formed at both the end point on the second liquid side and the end point on the first liquid side. Therefore, the interface formed in the through hole 250b restricts the light received by the light receiving unit 160b to the light passing through the region near the optical axis of the exit pupil 120.

  The through hole 250c of this example is formed by a side surface portion 642c having a fourth thickness included in the partition portion 640-3 and a side surface portion 644b having a first thickness included in the partition portion 640-4. In the through hole 250c of this example, the interface connecting the end points on the second liquid side of both side surfaces is assumed to have the same prism angle as the interface formed on the second liquid side of the through hole 250c illustrated in FIG. Therefore, the prism element formed at the interface restricts the light received by the light receiving element 162c to the light that has passed through the pupil region 122c. As shown by the broken line in the figure, the interface connecting the end points on the first liquid side of both side surfaces in the through hole 250c of this example has a prism angle inclined from the plane perpendicular to the optical axis. The prism element 142c having the prism angle restricts the light received by the light receiving element 162c to the light passing through the pupil region between the vicinity of the optical axis and the pupil region 122a in the exit pupil 120.

  The through hole 250d is formed by a first thickness side surface 642d included in the partition portion 640-3 and a fourth thickness side surface portion 644d included in the partition portion 640-5. The partition part 640-5 is a member similar to the partition part 640-2. For this reason, the prism elements formed in the through hole 250d are the same as the prism elements formed in the through hole 250a, and thus the description thereof is omitted.

  Further, according to the partition plate 242 of the present example, the prism element indicated by the alternate long and short dash line in the figure is formed like the prism element 680-2. The prism element indicated by the alternate long and short dash line has a smaller inclination than the prism angle indicated by the solid line such as the prism element 680-1 and has a larger inclination than the prism angle indicated by the broken line such as the prism element 680-3. have. A configuration for stably holding the prism element indicated by the one-dot chain line in the drawing will be described with reference to FIG.

  The control unit 180 can control the inclination of the liquid interface to any one of the solid line, the broken line, and the alternate long and short dash line in this example by controlling the internal pressure of the liquid region 210. That is, when the light receiving element 162 receives the subject light 130 that has passed through the pupil region 122 that does not include the optical axis in the exit pupil 120, the control unit 180 tilts the liquid interface with the first inclination with respect to the optical axis. When the subject light 130 that has passed through another pupil region 122 that does not include the optical axis in the exit pupil 120 is received by the light receiving element 162, the liquid interface is inclined to the second inclination with respect to the optical axis.

  According to the deflecting unit 140 of this example, the liquid interface can be controlled to three states as shown by the solid line, the alternate long and short dash line, and the broken line in the figure. For this reason, it is possible to capture images with different combinations of prism angles. That is, a blur image based on the MTF characteristics of the pupil region corresponding to each prism angle can be acquired.

  FIG. 6 shows a modification of the partition plate 242. A modification of the partition plate 242 will be described with reference to the portion B of FIG. 5 of the partition plate 242 illustrated in FIG.

  A protrusion 700 and a protrusion 701 are formed on the side surface 642a toward the inside of the through hole 250a. A protrusion 702, a protrusion 703, and a protrusion 704 are formed on the side surface 644a toward the inside of the through hole 250a. Each of the protrusions has such a thickness that the liquid interface is trapped. The protrusion 703 is located closer to the liquid region 220 than the protrusion 700 in the optical axis direction.

  In the first state, an interface is formed between the tip of the projection 700 at the end on the liquid region 220 side and the tip of the projection 702 at the end on the liquid region 220 side to form the prism element 680-1. . In the second state, an interface is formed between the tip of the projection 701 at the end on the liquid region 210 side and the tip of the projection 704 at the end on the liquid region 210 side to form the prism element 680-3. . In the third state, an interface is formed between the tip of the projection 700 at the end on the liquid region 220 side and the tip of the projection 703 of the side surface 644a to form the prism element 680-2.

  According to this example, since the side surface portion 642a and the side surface portion 644a have the protrusions, the liquid interface is easily trapped at the tip of the protrusion. Therefore, the prism angle can be controlled stably.

  In this example, the protrusion part formed in the through-hole 250a was demonstrated taking up the B part of FIG. Projections may be formed to trap the interface at the intended positions in all the through holes 250 of the partition plate 242, and the through holes 250 of the partition plate 242 described with reference to FIGS. Needless to say, a protrusion may be formed to trap the interface.

  As described above, the control unit 180 selects a combination of the pupil regions 122 that the light receiving unit 160 receives light so that the subject light forms an image on the light receiving unit 160 based on the MTF characteristics of the lens 110a. Specifically, the control unit 180 adjusts the inclination of the prism interface so that the direction of the light beam received by the corresponding light receiving element 162 is directed to the pupil region 122 through which the subject light imaged at the position of the light receiving unit 160 passes. Control. Further, the control unit 180 can control which pupil region 122 is used for imaging based on the MTF characteristic of the lens 110a.

  FIG. 7 schematically shows an example of the light receiving unit 20 including another deflecting optical element. The light receiving unit 20 of this example includes a microlens unit 150 and a light receiving unit 160. The micro lens unit 150 includes a plurality of micro lenses 952. The light receiving unit 160 includes a plurality of color filters 260, a plurality of light receiving elements 162, and a light shielding unit 262. The light receiving unit 20 of this example has a micro lens 952 as a deflection optical element instead of the prism element 142 as the deflection optical element described with reference to FIGS. Here, the difference from the light receiving unit 20 described with reference to FIGS. 1 to 8 will be mainly described.

  Light that has passed through substantially the entire surface of the exit pupil 120 enters the microlens 952. Also in this example, the microlens 952 has a refractive power that is large enough to cause each light receiving element 162 to receive light that has passed through a partial region of the exit pupil 120. Therefore, the size of the light beam that can be received by the light receiving element 162 is limited to that passing through a partial range of the exit pupil 120. In the light receiving unit 20 of this example, the optical axis of the micro lens 952 is provided so as to be deviated from the center position of the light receiving element 162 in a plane perpendicular to the optical axis of the lens system 100. The center position of the light receiving element 162 is the center position of a region through which light received by the light receiving element 162 and used for photoelectric conversion passes. In this example, the center position of the light receiving element 162 may be the center of the light receiving opening formed in the light shielding portion 262 located in the vicinity of the light receiving element 162.

  Each microlens 952 is designed to have a deviation amount so that the light having passed through a predetermined pupil region 122 is received by the corresponding light receiving element 162. The light beam that can be received by the light receiving element 162 is limited to a light beam that has passed through a partial region of the exit pupil 120 due to the refractive power and deviation of the micro lens 952. In this example, the microlens 952a limits the light that can be received by the light receiving element 162a through the light receiving opening to those that have passed through the pupil region 122a. Similarly, the microlenses 952b and c limit the light that can be received by the corresponding light receiving elements 162a and 162c through the light receiving openings to those that have passed through the pupil regions 122b and c, respectively. Similar to the microlens 952a, the microlens 952d restricts light that can be received by the light receiving element 162d through the light receiving opening to those that have passed through the pupil region 122a. As described above, the plurality of microlenses 952 are configured such that the optical axis is biased with respect to the light receiving opening of the light receiving element 162 in order to cause the corresponding light receiving element 162 to receive the subject light that has passed through the predetermined pupil region 122. Provided.

  Note that the microlens 152 or the microlens 952 described with reference to FIGS. 1 to 7 only needs to be able to limit the pupil size to such an extent that the difference in MTF characteristics can be ignored. Therefore, the control unit 180 may control the refractive power of the microlens 152 so as to limit the pupil size to such an extent that the difference in MTF characteristics can be ignored. At this time, the control unit 180 may control the refractive power of the microlens 152 so as to limit the pupil size to a different size for each MTF characteristic.

  FIG. 8 schematically shows an example of a light receiving unit including another deflecting optical element. The light receiving unit 20 of this example includes a microlens unit 150 and a light receiving unit 160. The micro lens unit 150 includes a plurality of micro lenses 1052. The light receiving unit 160 includes a plurality of color filters 260, a light shielding unit 1060 and a light shielding unit 1070, a plurality of light receiving elements 162 and a light shielding unit 262. The light receiving unit 20 of this example includes a light shielding unit 1060 and a light shielding unit 1070 as deflection optical elements instead of the prism element 142 as the deflection optical element described with reference to FIGS. Here, the difference from the light receiving unit 20 described with reference to FIGS. 1 to 8 will be mainly described.

  Light that has passed through substantially the entire surface of the exit pupil 120 enters the microlens 1052. In this example, the microlens 1052 has a refractive power that is large enough to collect light that has passed through substantially the entire surface of the exit pupil 120 toward the light receiving element 162. The refractive power of the microlens 1052 may be smaller than the refractive power of the microlens 152 or the microlens 952 described with reference to FIGS. In the light receiving unit 20 of this example, an opening 1062 and an opening 1072 are formed in the light shielding part 1060 and the light shielding part 1070, respectively. Of the light condensed toward the light receiving element 162 by the micro lens 1052, a part of the light that has passed through the opening 1062 and the opening 1072 enters the light receiving element 162 through the light receiving opening formed in the light shielding portion 262.

  The opening 1062 and the opening 1072 are provided so as to be deviated from each other in a plane perpendicular to the optical axis of the lens system 100. The positions of the openings 1062 and 1072 are designed so that the corresponding light receiving elements 162 receive the light that has passed through the predetermined pupil region 122. Due to the deviation of the opening 1062 and the opening 1072, the light beam that can be received by the light receiving element 162 is limited to that that has passed through a partial region of the exit pupil 120. In this example, the opening 1062 and the opening 1072 limit the light that can be received by the light receiving element 162a through the light receiving opening to those that have passed through the pupil region 122a. Since the openings corresponding to the light receiving elements 162b to 162d are the same, the description thereof is omitted. As described above, the light shielding unit 1060 and the light shielding unit 1070 have an opening having directivity to the pupil region 122 determined in advance with respect to the corresponding light receiving element 162.

  Instead of the light shielding unit 1060 and the light shielding unit 1070, the light shielding unit 262 may have an opening having directivity to the pupil region 122 that is predetermined with respect to the corresponding light receiving element 162.

  FIG. 9 schematically shows an example of the light receiving unit of this example. The light receiving unit 20 of this example has an opening 1264 of the light shielding portion 262 as a deflecting optical element instead of the prism element 142 as the deflecting optical element described with reference to FIGS.

  Light that has passed through substantially the entire surface of the exit pupil 120 enters the microlens 1052. In this example, the microlens 1052 has a refractive power that is large enough to collect light that has passed through substantially the entire surface of the exit pupil 120 toward the light receiving element 162. The refractive power of the microlens 1052 may be smaller than the refractive power of the microlens 152 or the microlens 952 described with reference to FIGS.

  In the light receiving unit 20 of this example, the opening 1264 of the light shielding unit 262 is provided so as to be deviated from the center position of the light receiving element 162 in a plane perpendicular to the optical axis of the lens system 100. Here, the center position of the light receiving element 162 is a center position of a region through which light received by the light receiving element 162 and used for photoelectric conversion passes.

  Each opening 1264 is designed to have a deviation amount so that light passing through a predetermined pupil region 122 is received by the corresponding light receiving element 162. Due to the deviation of the opening 1264, the light beam that can be received by the light receiving element 162 is limited to that that has passed through a partial region of the exit pupil 120. In this example, the opening 1264a limits the light that can be received by the light receiving element 162a to the light that has passed through the pupil region 122a. Similarly, openings 1264b and c limit the light that can be received by corresponding light receiving elements 162a and c to those that have passed through pupil regions 122b and c, respectively. Similarly to the opening 1264a, the opening 1264d restricts light that can be received by the light receiving element 162d to light that has passed through the pupil region 122a. As described above, the plurality of openings 1264 of the light shielding unit 262 are provided so as to be deviated from the center position of the light receiving element 162 so that the subject light passing through the predetermined pupil region 122 is received by the corresponding light receiving element 162. It is done.

  As described above, the light shielding unit 262 has an opening having directivity to the pupil region 122 predetermined with respect to the corresponding light receiving element 162.

  FIG. 10 shows an example of another block configuration of the imaging apparatus 1010. The imaging apparatus 1010 of this example includes a lens system 100, a light receiving unit 20, an image generation unit 170, and an image recording unit 190.

  The lens system 100 has the same configuration as the lens system 100 described with reference to FIGS. 1 to 6, and includes, for example, a lens system 100a that is a progressive power lens.

  The light receiving unit 20 includes a microlens unit 150 and a light receiving unit 160. The light receiving unit 20 of this example includes a deflecting optical element in the light receiving unit 160 instead of the deflecting unit 140 described with reference to FIGS. The microlens unit 150 includes a plurality of microlenses 152 and a light receiving element group 1162 corresponding to one microlens 152 as a deflection optical element. That is, a light receiving element group 1162a is provided corresponding to the micro lens 152a, a light receiving element group 1162b is provided corresponding to the micro lens 152b, and a light receiving element group 1162c is provided corresponding to the micro lens 152c.

  FIG. 11 is a schematic diagram illustrating an example of a microlens 152 viewed from the lens system 100 side and a light receiving element group 1162 provided corresponding to the microlens 152. As shown in the figure, one light receiving element group 1162 is arranged corresponding to one microlens 152, and the light receiving element group 1162 includes nine light receiving elements 1162-1a, 1b, 1c, and 1162. -2a, 2b, 2c, 1162-3a, 3b, 3c.

  The number of light receiving elements constituting the light receiving element group is not limited to nine, and may be determined as appropriate. Thus, the microlens 152 is provided for each of a plurality of light receiving element units. The microlens 152 has a refractive power large enough to cause the corresponding light receiving elements 1162-1a to 3c to receive the light that has passed through each region of the exit pupil 120.

  FIG. 12 is a schematic diagram illustrating the light receiving unit of the imaging apparatus 1010 in an enlarged manner. As shown in the figure, the light that has passed through the pupil region 122 a of the exit pupil 120 of the lens system 100 is received by the light receiving element 1162-1 (corresponding to the first light receiving element) by the microlens 152.

  The light that has passed through the pupil region 122b is received by the light receiving element 1162-2 (corresponding to the second light receiving element) by the microlens 152.

  Similarly, the light that has passed through the pupil region 122c is received by the light receiving element 1162-3 by the microlens 152.

  As described above, the microlens forms an imaging relationship between the pupil of the imaging lens and the plurality of light receiving cells, so that the light received by each light receiving element is a predetermined pupil region in the exit pupil 120 of the lens 110. Limited to those that have passed 122.

  Each light receiving element of the light receiving element group 1162 outputs an imaging signal having an intensity corresponding to the amount of received light to the image generation unit 170. The image generation unit 170 generates an image of the subject from the imaging signals of the plurality of light receiving element groups 1162. Specifically, the image generation unit 170 generates an image signal indicating an image with a different blur from the imaging signal supplied from the light receiving element group 1162. In this example, the light that can be received by each of the light receiving elements 1162-1, 2 and 3 of the light receiving element group 1162 is limited to light that has passed through the pupil regions 122a to 122c. Therefore, the image generation unit 170 generates a first blur image signal from the imaging signal of the light receiving element 1162-1 that receives the light that has passed through the pupil region 122a. The image generation unit 170 generates a second blur image signal from the imaging signal of the light receiving element 1162-2 that receives the light that has passed through the pupil region 122b. In addition, the image generation unit 170 generates a third blur image signal from the imaging signal of the light receiving element 1162-3 that receives the light that has passed through the pupil region 122c.

  In the present example, an example is shown in which light that has passed through three areas of the exit pupil of the microlens is incident on three light receiving elements in the vertical direction. Three areas of the exit pupil directed by the microlens correspond to imaging lens areas having different MTF characteristics. For this reason, three different blurred images can be obtained simultaneously and independently.

  FIG. 13 shows an example of another block configuration of the imaging apparatus 1110. The imaging device 1110 of this example includes a lens system 100, a light receiving unit 20, an image generation unit 170, and an image recording unit 190. The light receiving unit 20 includes a microlens unit 150, a polarization filter unit 1140, and a light receiving unit 160. The light receiving unit 20 of this example includes a polarizing filter unit 1140 as a deflecting optical element instead of the deflecting unit 140 described with reference to FIGS. The light receiving unit 160 has the same configuration as the light receiving unit 160 described with reference to FIGS. Here, it demonstrates centering on the difference with the imaging device 10 demonstrated over FIGS.

  In the imaging apparatus 1110 of this example, the lens system 100 includes a lens 110 and a polarization filter unit 1130. The polarizing filter unit 1130 is provided in the vicinity of the exit pupil. The polarizing filter unit 1130 includes a first polarizing filter 1132 and a second polarizing filter 1134 that are provided corresponding to different pupil regions in the exit pupil of the lens system 100. Light that has passed through the corresponding pupil regions is incident on the first polarizing filter 1132 and the second polarizing filter 1134. The first polarizing filter 1132 and the second polarizing filter 1134 selectively pass polarized components that are orthogonal to each other. Examples of combinations of orthogonal polarization components include linear polarization components whose polarization directions are orthogonal to each other. Other examples of combinations of orthogonal polarization components include a combination of a clockwise circularly polarized component and a counterclockwise circularly polarized component.

  The micro lens unit 150 includes a plurality of micro lenses 152. In this example, the microlens 152 has a refractive power that is large enough to condense light that has passed through substantially the entire surface of the exit pupil toward the light receiving element 162. The refractive power of the microlens 152 may be smaller than the refractive power of the microlens described with reference to FIGS. The polarization filter unit 1140 has a plurality of polarization filters 1142 provided corresponding to the plurality of light receiving elements 162. Among the polarizing filters 1142, the polarizing filter 1142 a passes the polarization component transmitted by the second polarizing filter 1134 and does not pass the polarization component transmitted by the first polarizing filter 1132. Of the polarizing filters 1142, the polarizing filter 1142 b allows the polarization component transmitted by the first polarization filter 1132 to pass, and does not allow the polarization component transmitted by the second polarization filter 1134 to pass. The polarizing filter unit 1140 includes a plurality of sets of polarizing filters 1142a and polarizing filters 1142b.

  The light receiving element 162 receives the light that has passed through the corresponding polarizing filter 1142. Specifically, the light receiving element 162a receives light that has passed through the polarizing filter 1142a. The light receiving element 162b receives the light that has passed through the polarizing filter 1142b. Therefore, the light received by the light receiving element 162a is limited to the light that has passed through the second polarizing filter 1134. The light received by the light receiving element 162 b is limited to the light that has passed through the first polarizing filter 1132. Therefore, the light receiving element 162a and the light receiving element 162b receive light that has passed through optical surfaces having different MTF characteristics of the lens system 100. The image generation unit 170 generates a first blur image from the light receiving element 162 that has received light that has passed through the second polarizing filter 1134 such as the light receiving element 162a. The image generation unit 170 generates a second blur image from the light receiving element 162 that has received the light that has passed through the first polarizing filter 1132 such as the light receiving element 162b. The imaging device 1110 of this example can also capture images with different blurring.

  As described above, the imaging device 1110 of this example is provided corresponding to the first and second polarizing filters 1132 and 1134 that transmit different polarization components in the plurality of pupil regions, and the plurality of light receiving elements 162, and is different. A plurality of polarizing filters 1142a and 114b each transmitting the polarization component are provided.

  FIG. 14 shows a modification of the imaging device 1110. The imaging device 1110 illustrated in FIG. 13 can capture images with two types of blur, whereas the imaging device 1110 of this example has a configuration capable of capturing images with four types of blur. Here, the configuration of the imaging apparatus 1110 of this example will be described mainly focusing on differences in the configuration of the lens system 100.

  The lens system 100 includes a polarizing filter unit 1230 provided in the vicinity of the exit pupil 1220 of the lens system 100 instead of the polarizing filter unit 1130 of FIG. The polarizing filter unit 1230 includes a first polarizing filter 1232a, a first polarizing filter 1232b, a second polarizing filter 1234a, and a second polarizing filter 1234b.

  The first polarizing filter 1232a and the second polarizing filter 1234a are provided corresponding to different regions in the pupil region 1222a in the exit pupil 1220. The light that has passed through the corresponding regions is incident on the first polarizing filter 1232a and the second polarizing filter 1234a. The first polarizing filter 1232a and the second polarizing filter 1234a selectively pass polarized components that are orthogonal to each other.

  The first polarizing filter 1232b and the second polarizing filter 1234b are provided corresponding to different regions in the pupil region 1222b in the exit pupil 1220. Light that has passed through the corresponding regions is incident on the first polarizing filter 1232b and the second polarizing filter 1234b. The first polarizing filter 1232b and the second polarizing filter 1234b selectively pass polarized components that are orthogonal to each other.

  The light flux toward the light receiving unit 160 included in the imaging device 1110 of this example is limited to the light beam that has passed through one of the pupil region 1222a and the pupil region 1222b. For example, as described with reference to FIGS. 1 to 6, the light flux toward the light receiving unit 160 can be limited by the prism element 142 and the microlens 152. Further, as described with reference to FIG. 7, the light flux toward the light receiving unit 160 can be limited by the deviation of the microlens 152. Further, as described with reference to FIG. 8, the light beam traveling toward the light receiving unit 160 can be limited by the light shielding unit. In addition, as described with reference to FIG. 12, in the light receiving unit 160, the light beam incident on the light receiving unit 160 is limited by the plurality of light receiving elements of the light receiving element group 1162 provided corresponding to one microlens 152. can do.

  Of the light receiving elements 162 that receive the light that has passed through the pupil region 1222a, the light receiving elements 162 provided corresponding to the polarizing filter 1142a can receive the light that has passed through the first polarizing filter 1232a. Therefore, the light received by the light receiving element 162 is limited to the light that has passed through the first polarizing filter 1232a. On the other hand, among the light receiving elements 162 that receive the light that has passed through the pupil region 1222a, the light receiving element 162 provided corresponding to the polarizing filter 1142b can receive the light that has passed through the second polarizing filter 1234a. Therefore, the light received by the light receiving element 162 is limited to the light that has passed through the second polarizing filter 1234a.

  In addition, among the light receiving elements 162 that receive the light that has passed through the pupil region 1222b, the light receiving element 162 that is provided corresponding to the polarizing filter 1142a can receive the light that has passed through the first polarizing filter 1232b. Therefore, the light received by the light receiving element 162 is limited to the light that has passed through the first polarizing filter 1232b. On the other hand, among the light receiving elements 162 that receive the light that has passed through the pupil region 1222b, the light receiving element 162 that is provided corresponding to the polarizing filter 1142b can receive the light that has passed through the second polarizing filter 1234b. Therefore, the light received by the light receiving element 162 is limited to the light that has passed through the second polarizing filter 1234b.

  In this example, the optical element is divided into two or more pupil areas such as a pupil area 1222a and a pupil area 1222b by the deflection optical element. In the divided pupil area, at least one of the pupil areas is further divided by a polarizing filter. That is, the imaging device 1110 can separately capture images through three or more different pupil regions by a combination of the deflection optical element and the polarization filter. For this reason, imaging can be performed with three or more different MTF characteristics.

  Although the embodiment of dividing the pupil region by the polarizing filter has been described with reference to FIGS. 13 and 14, a wavelength filter can be used instead of the polarizing filter illustrated in FIGS. That is, the imaging device 1110 includes a first wavelength filter that transmits different wavelength components in a plurality of pupil regions and a second wavelength filter that is provided corresponding to the plurality of light receiving elements 162 and transmits different wavelength components, respectively. You may have more than one. As the wavelength filter, two or more wavelength filters that respectively transmit light of two or more partial wavelength regions belonging to the red wavelength region, two or more wavelength filters that respectively transmit two or more partial wavelength regions belonging to the green wavelength region, Two or more wavelength filters that respectively transmit two or more partial wavelength ranges belonging to the blue wavelength range may be used. In this case, each blur image can be formed by light of three partial wavelength ranges selected from the red wavelength range, the green wavelength range, and the blue wavelength range. In this way, a color image can be captured while limiting the pupil region also by the wavelength filter.

  FIG. 15 is a schematic view of a lens system having different MTF characteristics for each region through which incident light passes, as viewed from the optical axis direction. Here, FIG. 15A is an example of the lens system 100 described in relation to FIGS. The lens system 100 shown in the figure is a lens system in which the MTF characteristics of each region are asymmetric. In the figure, a region 105a is a region having a first MTF characteristic, a region 105b is a region having a second MTF characteristic, and a region 105c is a region having a third MTF characteristic, and a pupil region 122a and a pupil of the exit pupil 120 of the lens system 100, respectively. It corresponds to the region 122b and the pupil region 122c. It should be noted that what region has what MTF characteristics can be determined as appropriate.

  FIG. 15B is a schematic diagram of another lens system having different MTF characteristics for each region through which incident light passes. In FIG. 15B, a region 1305a is a region having a first MTF characteristic, a region 1305b is a region having a second MTF characteristic, and a region 1305c is a region having a third MTF characteristic. As described above, the lens system 1300 shown in FIG. 15B is a rotationally symmetric type in which the MTF characteristics differ depending on the distance from the optical axis, but the optical surfaces equidistant from the optical axis provide the same MTF characteristics. In the lens system 1300, it can be said that the MTF characteristics are distributed concentrically.

  FIG. 16 schematically illustrates an example of a block configuration of an imaging device 1210 having a lens system 1300. Here, a region 1305a is formed in the annular pupil region 2222a of the exit pupil 2220 of the lens system 1300, a region 1305b is formed in the annular pupil region 2222b, and a region 1305c is formed in the central circular pupil region 2222c. , Respectively. Accordingly, of the subject light that has passed through the lens system 1300, light that has passed through the pupil region 2222a of the exit pupil 2220 of the lens system 1300 has passed through the first MTF characteristic, and light that has passed through the pupil region 2222b has passed through the second MTF characteristic, pupil region 122c. The light thus obtained has the third MTF characteristics.

  In the lens system 1300 of this example, the subject light received by the light receiving element 162 passes through one of the pupil areas 222a to 222c located at different distances from the optical axis in the exit pupil 2220 of the lens system 1300. It is limited to what you did. The restriction of the pupil region is realized by a deflecting optical element as described in connection with FIGS. For example, as described with reference to FIGS. 1 to 6, the light flux toward the light receiving unit 160 can be limited by the prism element 142 and the microlens 152. Further, as described with reference to FIG. 7, the light flux toward the light receiving unit 160 can be limited by the deviation of the microlens 152. Further, as described with reference to FIGS. 8 and 11, the light flux toward the light receiving unit 160 can be limited by the light blocking unit. In addition, as described with reference to FIG. 12, in the light receiving unit 160, the light beam incident on the light receiving unit 160 is limited by the plurality of light receiving elements of the light receiving element group 1162 provided corresponding to one microlens 152. can do.

  In addition, the light beam incident on the light receiving unit 160 can be limited by the light shielding mask shown in FIG.

  FIGS. 17A to 17C are perspective views showing the shapes of the light shielding mask 2262-1, the light shielding mask 2262-2, and the light shielding mask 2262-3 formed on the light receiving surface of each light receiving element. The opening of the light shielding mask 2262-1 has a shape similar to that of the region 1305c, and is shaped to receive light only at the center of the light receiving element 162. Further, the opening of the light shielding mask 2262-2 has a shape similar to that of the region 1305b, and the light is received only by the annular portion corresponding to the peripheral portion of the opening of the light shielding mask 2262-1. Further, the opening of the light shielding mask 2262-3 has a shape similar to that of the region 1305a, and the light is received only by the annular portion corresponding to the peripheral portion of the opening of the light shielding mask 2262-2.

  FIG. 18 is an overhead view schematically showing the lens system 1300, the respective microlenses 1052a to 1052c, the respective light shielding masks 2262-1 to 2262-3, and the respective light receiving elements 162a to 162c. FIG. 19 is a cross-sectional view schematically showing an example of the light receiving unit of this example.

  The light receiving unit 20 of this example includes one light receiving element corresponding to one microlens. In the example of FIG. 19, a light receiving element 162a corresponding to the microlens 1052a, a light receiving element 162b corresponding to the microlens 1052b, a light receiving element 162c corresponding to the microlens 1052c, and a light receiving element 162d corresponding to the microlens 1052d. Each is arranged. The center position of each microlens 1052 and the center position of each light receiving element 162 are arranged to coincide.

  A light shielding portion 2262a is formed on the light receiving surface of the light receiving element 162a, a light shielding portion 2262b is formed on the light receiving surface of the light receiving device 162b, and a light shielding portion 2262c is formed on the light receiving surface of the light receiving element 162c. Yes. Here, the light shielding portion 2262a is the shape of the light shielding mask 2262-1, the light shielding portion 2262b is the shape of the light shielding mask 2262-2, and the light shielding portion 2262c is the light shielding portion of the shape of the light shielding mask 2262-3.

  Further, a light shielding portion 2262d is formed on the light receiving surface of the light receiving element 162d. The light shielding part 2262d has the shape of a light shielding mask 2262-1, similar to the light shielding part 2262a. Although not shown in the drawing, the light shielding masks 2262-1 to 2262-3 are repeatedly arranged according to a predetermined rule on the light receiving surface of each light receiving element 162.

  Light that has passed through substantially the entire surface of the exit pupil 1320 is incident on each microlens 1052. Here, light that has passed through the microlens 1052a is limited to only light that has passed through the pupil region 2222a by the light shielding portion 2262a having the shape of the light shielding mask 2262-1, and only light that has passed through the pupil region 2222a is incident on the light receiving element 162a. Received light. Therefore, only the subject light having the first MTF characteristic is received by the light receiving element 162a.

  Similarly, of the light that has passed through the microlens 1052b, only the light that has passed through the pupil region 2222b is received by the light receiving element 162b by the light shielding portion 2262b having the shape of the light shielding mask 2262-2. Further, only the light that has passed through the pupil region 2222a among the light that has passed through the microlens 1052c is received by the light receiving element 162c by the light shielding portion 2262c having the shape of the light shielding mask 2262-3. Therefore, only the subject light having the second MTF characteristic is received by the light receiving element 162b, and only the subject light having the third MTF characteristic is received by the light receiving element 162c.

  As described above, the plurality of light shielding masks 2262 of the light shielding unit 262 are similar to the regions of the MTF characteristics of the lens system 1300 so that subject light that has passed through the predetermined pupil region 2222 is received by the corresponding light receiving element 162. Provided in the shape. Thereby, the image generation unit 170 can obtain the first blurred image, the second blurred image, and the third blurred image from the imaging signal of each light receiving element 162.

  Furthermore, it is possible to limit the light flux incident on the light receiving unit 160 by using microlenses having different focal lengths.

  FIG. 20 schematically shows an example of the light receiving unit of this example. The light receiving unit 20 of this example includes one light receiving element corresponding to one microlens. In the example of FIG. 20, the light receiving element 162a corresponding to the micro lens 1252a, the light receiving element 162b corresponding to the micro lens 1252b, the light receiving element 162c corresponding to the micro lens 1252c, and the light receiving element 162d corresponding to the micro lens 1252d. Each is arranged. Note that the center position of each microlens 1252 and the center position of each light receiving element 162 are arranged to coincide with each other.

  Further, a light shielding portion 2362 is disposed on the light receiving surface of each light receiving element 162. Similarly to the light shielding mask 2262-2 shown in FIG. 17B, the light shielding portion 2362 includes a circular light shielding mask and an annular light shielding mask, and has an annular opening. The width of the opening can be determined as appropriate so that the luminous flux can be appropriately limited.

Here, each microlens 1252 has a different focal length. In the example of FIG. 20, the focal length of the microlens 1252a is the first focal length f _1, and has a focal position on the light receiving surface of the light receiving element 162a. The focal length of the microlens 1252b, the first is the focal length focal length f ₂ shorter second than f _1, having a focal position in front (micro lens side) of the light receiving surface of the light receiving element 162b. The focal length of the microlens 1252c is located a third focal length f ₃ of shorter than the second focal length f _2, having a focal position further forward than the focal position of the microlens 1252b (micro lens side).

Moreover microlenses 1252d is configured similarly to the microlens 1252a, focal length of the microlens 1252d has a focal length _{f 1} of the first. Although not shown in the drawing, each microlens 1252 having the first focal length f ₁ , the second focal length f ₂ , and the third focal length f ₃ is repeatedly arranged according to a predetermined rule.

Next, the relationship between the light incident on each microlens 1252 and the light received by the corresponding light receiving element 162 will be described. Figure 21 is a light receiving element 162a incident on the microlens 1252a having a first focal length f ₁ is a diagram showing the relationship between the light received.

  Light that has passed through substantially the entire surface of the exit pupil 2220 is incident on the microlens 1252a. Here, the light passing through the pupil region 2222c in the exit pupil 2320 is limited by the circular light shielding mask at the center of the light shielding portion 2362 and does not enter the light receiving element 162a, as shown in FIG. Similarly, light passing through the pupil region 2222b in the exit pupil 2220 is limited by the circular light shielding mask at the center of the light shielding portion 2362 and does not enter the light receiving element 162a, as shown in FIG. 21B.

  On the other hand, light that has passed through the pupil region 2222a in the exit pupil 2220 enters the light receiving element 162a from the opening of the light shielding portion 2362 as shown in FIG.

  Thus, the light that has passed through the microlens 1252a is limited to only the light that has passed through the pupil region 2222a by the microlens 1252a and the light-shielding portion 2362, and only the light that has passed through the pupil region 2222a is received by the light receiving element 162a. Therefore, only the subject light having the first MTF characteristic is received by the light receiving element 162a.

Figure 22 is a second focal length f ₂ light receiving element 162b incident on the microlens 1252b having is a diagram showing the relationship between the light received.

  Light that has passed through substantially the entire surface of the exit pupil 2220 is incident on the microlens 1252b. Here, the light passing through the pupil region 2222c in the exit pupil 2220 is limited by the circular light shielding mask at the center of the light shielding portion 2362 and does not enter the light receiving element 162b, as shown in FIG.

  On the other hand, light that has passed through the pupil region 2222b in the exit pupil 2220 enters the light receiving element 162b through the opening of the light shielding portion 2362, as shown in FIG.

  In addition, the light that has passed through the pupil region 2222a in the exit pupil 2220 is limited by the annular light shielding mask of the light shielding portion 2362 and does not enter the light receiving element 162b, as shown in FIG.

  As described above, the light that has passed through the microlens 1252b is limited to only the light that has passed through the pupil region 2222b by the microlens 1252b and the light shielding unit 2362, and only the light that has passed through the pupil region 2222b is received by the light receiving element 162b. Therefore, only the subject light having the second MTF characteristic is received by the light receiving element 162b.

FIG. 23 is a diagram illustrating a relationship between light incident on the microlens 1252c having the _third focal length f3 and light received by the light receiving element 162c.

  Light that has passed through substantially the entire surface of the exit pupil 2220 is incident on the microlens 1252c. Here, the light that has passed through the pupil region 2222c in the exit pupil 2220 enters the light receiving element 162c through the opening of the light shielding portion 2362, as shown in FIG.

  On the other hand, the light passing through the pupil region 2222b in the exit pupil 2220 is limited by the annular light shielding mask of the light shielding portion 2362 and does not enter the light receiving element 162c, as shown in FIG. Similarly, light passing through the pupil region 2222a in the exit pupil 2220 is limited by the annular light shielding mask of the light shielding portion 2362 and does not enter the light receiving element 162c, as shown in FIG.

  Thus, the light that has passed through the microlens 1252c is limited to only the light that has passed through the pupil region 2222c by the microlens 1252c and the light-shielding portion 2362, and only the light that has passed through the pupil region 2222c is received by the light receiving element 162c. Therefore, only the subject light having the third MTF characteristic is received by the light receiving element 162c.

  As described above, the focal length of each microlens 1252 is set and the light shielding portion 2362 is arranged so that the subject light that has passed through the predetermined pupil region 2222 is received by the corresponding light receiving element 162. Thereby, the image generation unit 170 can obtain the first blurred image, the second blurred image, and the third blurred image from the imaging signal of each light receiving element 162.

  Thus, since the lens system 1300 of this example also has different MTF characteristics depending on the distance from the optical axis, it is possible to capture a plurality of images with different blurring.

  Returning to the description of FIG. 15, in the lens system 1400 shown in FIG. 15C, the region 1405a is a region having the first MTF characteristic, and the region 1405b is a region having the second MTF characteristic. In the lens system 1400, only a substantially circular part of the entire area of the lens system is an area 1405b, and the other area is an area 1405a.

  Further, in the lens system 1500 shown in FIG. 15D, the lens system region is divided into cross characters by a two-dimensional straight line. Here, the region 1505a is a region having a first MTF characteristic, the region 1505b is a region having a second MTF characteristic, the region 1505c is a region having a third MTF characteristic, and the region 1505d is a region having a fourth MTF characteristic. Further, in the lens system 1600 shown in FIG. 15E, the lens system 1600 is divided by using both the radius and the azimuth, and is a substantially circular region at the center portion of the lens system region, and the region 1605a having the first MTF characteristic. In addition, the second region includes a second MTF region 1605b, a third MTF region 1605c, a fourth MTF region 1605d, and a fifth MTF region 1605e that are divided into four equal parts. As described above, regions having different MTF characteristics can be freely arranged. In addition, the areas of each MTF characteristic may have different areas.

  Further, in FIGS. 1 to 15, the lens system in which the MTF characteristics change discontinuously has been described. However, the lens system in which the MTF characteristics change continuously is described with reference to FIGS. 1 to 15. It can also be adopted as a system.

  FIG. 24 is a diagram schematically showing how the light incident on the lens is separated and extracted as an image signal.

  FIG. 24A shows a lens system 100 having different MTF characteristics for each region through which incident light passes, a light receiving unit 20 that receives light by restricting a luminous flux for each pupil region, and blurs that differ from image signals for each MTF property. An image generation unit 170 capable of generating a taste image is shown. This lens system 100 is designed to intentionally drop the MTF around the lens.

  FIG. 24B shows a normal lens system 1700, an optical filter 1710 having a different MTF characteristic for each region through which incident light passes, and an image capable of generating a different blur image from an image signal for each MTF characteristic. A generation unit 170 is shown. As described above, even if the optical system is configured by the normal lens system 1400 and the optical filter having different MTF characteristics for each region, it is possible to simultaneously capture a plurality of images having different blurring as described above. It is. The optical filter 1710 may have a lens effect.

  In FIG. 1 to FIG. 24, the case where the spatial frequency (MTF characteristic) is different as an example in which the characteristic is different for each region through which incident light passes is described. However, the characteristic is different for each region. Can be captured simultaneously. For example, lens systems having different polarization characteristics, dimming characteristics, and cross filter characteristics for each region can be used.

  The cross filter is a filter for generating light streaks (light stripes) centered on a portion with high luminance of a subject by forming a groove on the surface of transparent optical glass. As the cross filter characteristics, the strength of light streaks, the direction (0 degrees / 90 degrees, 45 degrees / 135 degrees, etc.), and the shape (cross, six directions, etc.) are conceivable.

  As an example, the region is divided as in the lens system 1500 shown in FIG. 15D, the region 1505a has no cross filter characteristics, the region 1505b has low cross filter strength, the region 1505c has cross filter characteristics, and the region 1505d has a cross filter characteristic. The cross filter characteristics may be different for each region such as high strength.

  As another example, the region is divided as in the lens system 1600 shown in FIG. 15E, the region 1605a has no cross filter characteristics, the region 1605b has a high intensity, the orientation is 0 degrees / 90 degrees, and the region 1605c has an intensity. Is weak and the azimuth is 45 degrees / 135 degrees, the area 1605d is strong and the azimuth is 45 degrees / 135 degrees, the area 1605b is weak and the azimuth is 0 degrees / 90 degrees, and the cross filter for each area. The characteristics may be different. It is possible to appropriately determine which region has what cross filter characteristics.

  By applying such a lens system to the imaging device described with reference to FIGS. 1 to 24, it is possible to simultaneously capture images having different cross filter characteristics.

  As mentioned above, although this invention was demonstrated using embodiment, the technical scope of this invention is not limited to the range as described in the said embodiment. It will be apparent to those skilled in the art that various modifications or improvements can be added to the above-described embodiment. It is apparent from the scope of the claims that the embodiments added with such changes or improvements can be included in the technical scope of the present invention.

  The order of execution of each process such as operations, procedures, steps, and stages in the apparatus, system, program, and method shown in the claims, the description, and the drawings is particularly “before” or “prior to”. It should be noted that the output can be realized in any order unless the output of the previous process is used in the subsequent process. Regarding the operation flow in the claims, the description, and the drawings, even if it is described using “first”, “next”, etc. for convenience, it means that it is essential to carry out in this order. It is not a thing.

  DESCRIPTION OF SYMBOLS 10, 1010, 1110, 1210 ... Imaging device, 20 ... Light receiving unit, 100, 1300, 1400, 1500 ... Lens system, 110, 1310 ... Lens, 115 ... Optical device, 120, 1220, 1320, 2220 ... Exit pupil, 122 2222 ... Pupil area 130 ... Subject light 140 ... Deflection part 142 ... Prism element 150 ... Microlens part 152, 952, 1052, 1252 ... Microlens 160 ... Light receiving part 162, 1162-1, 2 DESCRIPTION OF SYMBOLS 3 ... Light receiving element, 170 ... Image generation part, 180 ... Control part, 190 ... Image recording part, 200 ... Housing, 210, 220, 230 ... Liquid area | region, 240, 640 ... Partition part, 242 ... Partition plate, 250 ... Through-hole, 252 254 642 644... Side portion 260 260 color filter 262 light-shielding portion 64, 1264 ... aperture, 281, 282, 680 ... prism element, 290, 291, 292 ... drive unit, 280 ... elastic surface, 350 ... row direction, 360 ... column direction, 400 ... image surface, 510 ... first blurring Image 520 ... Second blur image 530 ... Third blur image 550 ... Composite image 512, 522, 532, 552 ... Short-distance subject image 514, 524, 534, 554 ... Medium-distance subject image 516 526, 536, 556 ... Long-distance subject image, 700, 701, 702, 703, 704 ... Projection, 1060, 1070 ... Shading part, 1062, 1072 ... Opening, 1130, 1140 ... Polarization filter part, 1132 ... First Polarizing filter, 1134, second polarizing filter, 1422, polarizing filter, 1162, 2162, light receiving element group, 1232, first polarizing filter 1234 ... second polarizing filter 1230 ... polarizing filter sections, 1322 ... partial pupil region, 2262,2263 ... shielding portion

Claims (14)

An imaging optical system including an imaging lens, the imaging optical system having different spatial frequency characteristics for each region through which incident light passes; and
A light receiving section having a plurality of light receiving elements;
A plurality of optical elements provided corresponding to the plurality of light receiving elements, respectively, and causing the corresponding light receiving elements to receive subject light that has passed through a predetermined pupil region in the exit pupil of the imaging lens;
An image generation unit that generates an image of a subject from imaging signals of the plurality of light receiving elements,
A plurality of first optical elements among the plurality of optical elements correspond to light receiving elements corresponding to subject light passing through the first pupil region of the exit pupil and the region having the first spatial frequency characteristic of the imaging lens. Incident on
The plurality of second optical elements among the plurality of optical elements correspond to light receiving elements corresponding to subject light passing through the second pupil region of the region having the second spatial frequency characteristic of the imaging lens and the exit pupil. is incident to,
Each of the plurality of optical elements is a prism element that causes a corresponding light receiving element to receive subject light that has passed through the predetermined pupil region, and is between the first liquid and the second liquid having different refractive indexes. A liquid prism element in which a prism interface is formed at the liquid interface;
By controlling the tilt of the prism surface relative to the optical axis of the imaging lens, and further comprising said Rukoto a control unit for controlling the direction of the light beam received in the light receiving elements respectively corresponding to a plurality of the prism elements An imaging device. A prism housing that holds the first liquid and the second liquid;
A partition plate that divides the interior of the prism housing into a first region filled with the first liquid and a second region filled with the second liquid along the optical axis;
The partition plate has a plurality of through holes corresponding to positions where the plurality of liquid prism elements are formed,
The control unit controls the position of the liquid interface in the first side surface portion of each of the plurality of through-holes and the position of the liquid interface in the second side surface portion facing the first side surface portion. The image pickup apparatus according to claim 1 , wherein an inclination of the prism interface with respect to is controlled. The control unit, when causing the light receiving element to receive subject light that has passed through a pupil region including the optical axis in the exit pupil, causes the liquid interface to be substantially orthogonal to the optical axis, and The imaging apparatus according to claim 2 , wherein the liquid interface is inclined with respect to the optical axis when subject light that has passed through a pupil region that does not include an optical axis is received by the light receiving element. The control unit, when causing the light receiving element to receive subject light that has passed through a pupil region that does not include the optical axis in the exit pupil, tilts the liquid interface with respect to the optical axis to a first inclination, When the subject light that has passed through another pupil region not including the optical axis in the exit pupil is received by the light receiving element, the liquid interface is inclined to a second inclination with respect to the optical axis. The imaging device according to claim 2 . At least one of the plurality of through holes has the first side surface portion and the second side surface portion having different thicknesses,
The control unit is configured such that a region surrounded by the first side surface portion and the second side surface portion is filled with the first liquid and a state where the region is filled with the second liquid. by switching, imaging device according to claim 2 in any one of 4, characterized in that switching the liquid surface with respect to the optical axis to different slopes. The plurality of light receiving elements are arranged in a matrix.
The partition plate is formed by alternately providing a first partition portion extending in the column direction and a second partition portion extending in the column direction in the row direction,
The first partition has side portions having a first thickness on both sides along the optical axis direction,
The second partition portion has side portions with a second thickness on both sides along the optical axis direction,
The plurality of through holes are respectively formed by a side surface portion of the first partition portion and a side surface portion of the second partition portion adjacent to the first partition portion,
The first liquid side of the first partition and the second partition forms a substantially identical plane;
The control unit fills the first liquid in a region surrounded by the first side surface portion and the second side surface portion so that the inclination of the liquid interface with respect to the optical axis is different from each other in the row direction. the imaging apparatus according to any one of claims 2 to 5, characterized in that to control the state. The said control part controls the inclination of the said prism interface with respect to the said optical axis by controlling the internal pressure of the area | region holding the said 1st liquid, The any one of Claim 2 to 6 characterized by the above-mentioned. Imaging device. An imaging optical system including an imaging lens, the imaging optical system having different spatial frequency characteristics for each region through which incident light passes; and
A light receiving section having a plurality of light receiving elements;
A plurality of optical elements provided corresponding to the plurality of light receiving elements, respectively, and causing the corresponding light receiving elements to receive subject light that has passed through a predetermined pupil region in the exit pupil of the imaging lens;
An image generation unit that generates an image of a subject from imaging signals of the plurality of light receiving elements,
A plurality of first optical elements among the plurality of optical elements correspond to light receiving elements corresponding to subject light passing through the first pupil region of the exit pupil and the region having the first spatial frequency characteristic of the imaging lens. Incident on
The plurality of second optical elements among the plurality of optical elements correspond to light receiving elements corresponding to subject light passing through the second pupil region of the region having the second spatial frequency characteristic of the imaging lens and the exit pupil. is incident to,
The imaging optical system has a different spatial frequency for each of the circular region and the annular region divided by the distance from the center of the imaging lens,
Wherein the plurality of optical elements, the imaging apparatus according to claim opaque element der Rukoto forming the opening of the micro lens and the annular shape having different focal lengths respectively.   The imaging apparatus according to claim 8, wherein one light receiving element is provided corresponding to one microlens.   The micro lenses of the plurality of first optical elements have a focal position on the light receiving surface of the light receiving element, and the micro lenses of the plurality of second optical elements have a focal position before the light receiving surface of the light receiving element. The imaging device according to claim 8 or 9, comprising: The imaging optical system, an imaging apparatus according to any one of claims 1 to 10, wherein the imaging lens is characterized as having a different spatial frequency characteristic for each region. The imaging optical system, an imaging apparatus according to any one of claims 1 to 10, characterized in that it comprises an optical filter having a different spatial frequency characteristic for each region. An imaging optical system including an imaging lens, the imaging optical system having different cross-filter characteristics for each region through which incident light passes; and
A light receiving section having a plurality of light receiving elements;
A plurality of optical elements provided corresponding to the plurality of light receiving elements, respectively, and causing the corresponding light receiving elements to receive subject light that has passed through a predetermined pupil region in the exit pupil of the imaging lens;
An image generation unit that generates an image of a subject from imaging signals of the plurality of light receiving elements,
The plurality of first optical elements among the plurality of optical elements correspond to light receiving elements corresponding to subject light passing through the first pupil region in the exit pupil and the region having the first cross filter characteristic of the imaging lens. Incident on
A plurality of second optical elements among the plurality of optical elements correspond to light receiving elements corresponding to subject light passing through the second pupil region of the exit pupil and the region having the second cross filter characteristic of the imaging lens. An imaging apparatus characterized by being made incident on a light source. The image generating unit selects which pupil region of the exit pupil should generate the subject image based on the subject light that has passed through, and captures a plurality of light receiving elements that receive the subject light that has passed through the selected pupil region using the signal, the imaging apparatus according to any one of claims 1 to 13 and generating an image of the object.

Images