JP2010283651A - Imaging device, and imaging element unit - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an imaging device including a plurality of imaging elements different in positions of focus detection pixels as a unit detachable by being replaced for one imaging device body, and allowing a user to change over a focus detection function in accordance with an object. <P>SOLUTION: When this imaging element unit is mounted, the imaging device body reads imaging element unit information (S110), and specifies the position of a focus detection pixel of the imaging element unit to be displayed by being superposed on a shot image (S150). A defocus amount is calculated based on the imaging element unit information and focus detection pixel data (S160), and automatic focus adjustment control is made (S180). <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an image pickup apparatus and an image pickup element unit including an image pickup element.

  There is known an imaging apparatus including an imaging element in which focus detection pixels using a pupil division type phase difference detection method are arranged in the horizontal direction at the center of the imaging element and imaging pixels are arranged in the periphery thereof (for example, patents) Reference 1).

  Various variations are required for the focus detection function of the image sensor used in such an image pickup apparatus. For example, even if the layout of the focus detection position is taken, only one point at the center of the screen / the center of the screen + up / down / left / right periphery There are many variations such as 5 points / center of the screen + 5 points in the periphery of the screen diagonal / many on the grid points in the screen. In the case of an image sensor having a large number of focus detection positions from the beginning, a complicated operation is required to select a desired focus detection position, or by interpolating image data at a large number of focus detection pixel positions. There was a risk that the image quality would be degraded. Other variations of the focus detection function include the pixel size of the focus detection pixels (focus detection accuracy) / the arrangement direction of the focus detection pixels.

JP-A-1-216306

  When the user wants to switch the focus detection function according to the situation, it is necessary to prepare an image pickup apparatus equipped with an image pickup device having each focus detection function. For example, an image pickup apparatus A equipped with an image pickup element that does not include a focus detection pixel to obtain a high-quality image, an image pickup apparatus B equipped with an image pickup element with a relatively small focus detection position to take a still subject, and a moving subject In order to take a picture, it is necessary to prepare an image pickup apparatus C equipped with an image pickup element having a large number of focus detection positions, which is a heavy burden on the user.

  In addition, when a user wants to use an image pickup device having the latest focus detection function, it is necessary to prepare a new image pickup apparatus equipped with the image pickup device.

  The subject of this invention is providing the imaging device which does not become a big burden on a user, implement | achieving the focus detection function by the pixel for a focus detection incorporated in the image pick-up element.

An image pickup apparatus according to a first aspect of the present invention includes an image pickup element having an image pickup pixel and a focus detection pixel, an image pickup element unit including unit communication means, a mounting portion on which the image pickup element unit is detachably mounted, and a photographing optical system. And a main body including main body communication means, the imaging pixel outputs an imaging signal, the focus detection pixel outputs a focus detection signal for detecting a focus adjustment state of the imaging optical system, and the imaging element unit When mounted on the mounting portion, the focus detection related information related to the detection of the focus adjustment state is transmitted / received to / from the main body via communication between the unit communication means and the main body communication means.
An image pickup apparatus according to a seventh aspect of the present invention includes a main body including a photographing optical system, a mounting unit, and main body communication means, a first image pickup element unit including an image pickup element having an image pickup pixel and a focus detection pixel, and unit communication means. A second imaging element unit including at least an imaging element having an imaging pixel and unit communication means, and each imaging pixel included in the first and second imaging element units outputs an imaging signal, The focus detection pixel outputs a focus detection signal for detecting the focus adjustment state of the photographing optical system, and each of the first and second image sensor units can be detachably attached to the mounting portion of the apparatus main body. When the first image sensor unit is mounted on the mounting portion, the main body control means is connected to the first image sensor unit via communication between the unit communication means included in the first image sensor unit and the main body communication means. Imaging element Unit communication means and main body included in the second image sensor unit when the first information related to the detection of the focus adjustment state with the unit is received and the second image sensor unit is mounted on the mounting unit 2nd information different from 1st information is received via communication with a communication means, and it is a 1st image pick-up element unit with which the mounting part is mounted | worn, or 2nd image sensor The focus adjustment state detection process is performed according to whether the unit is a unit.
An image sensor unit according to a thirteenth aspect of the present invention is a first image sensor unit used in the image pickup apparatus according to any one of the seventh to twelfth aspects.

  According to the imaging apparatus of the present invention, it is possible for the user to switch various focus detection functions depending on the situation without imposing a heavy burden on the user.

FIG. 6 illustrates a camera system according to this embodiment. The block diagram which shows the structure of a camera system. FIG. 4 is a diagram illustrating a focus detection position on a shooting screen in the image sensor unit A. The figure explaining the principle of a pupil division type phase difference detection system. FIG. 3 is a partially enlarged front view showing a detailed configuration of an image sensor of the image sensor unit A. The figure which shows the shape of the micro lens of an imaging pixel and a focus detection pixel. The figure which shows the shape of the micro lens of an imaging pixel. The figure which shows the shape of the micro lens of a focus detection pixel. The figure which shows the spectral characteristic of a green pixel, a red pixel, and a blue pixel. The figure which shows the spectral characteristic of a focus detection pixel. Sectional drawing of an imaging pixel. Sectional drawing of a focus detection pixel. The figure which shows the structure of the focus detection optical system of the pupil division type phase difference detection system using a micro lens. The figure which shows the mode of the imaging | photography light beam which an imaging pixel receives. FIG. 6 is a diagram illustrating a focus detection position on a shooting screen in the image sensor unit B. FIG. 4 is a partially enlarged front view showing a detailed configuration of an image sensor of the image sensor unit B. FIG. 4 is a diagram showing a focus detection position on a shooting screen in the image sensor unit C. FIG. 4 is a partially enlarged front view showing a detailed configuration of an image sensor of the image sensor unit C. FIG. 4 is a diagram illustrating a focus detection position on a shooting screen in the image sensor unit D. FIG. 3 is a partially enlarged front view showing a detailed configuration of an image sensor of the image sensor unit D. The flowchart which shows the imaging operation of the body control apparatus of a camera system. The flowchart which shows the imaging operation of the unit control apparatus of a camera system. The flowchart which shows the imaging operation of the lens control apparatus of a camera system. The figure which shows the relationship of the correlation amount C (k) with respect to the shift amount k of a pair of data. The flowchart which shows the imaging operation of the body control apparatus of the camera system by other embodiment. The flowchart which shows the imaging operation of the unit control apparatus of the camera system by other embodiment. The figure which shows the focus detection position on the imaging | photography screen in the image pick-up element unit by other embodiment. The partial enlarged front view which shows the detailed structure of the image pick-up element of the image pick-up element unit by other embodiment. The figure which shows the shape of the micro lens of the focus detection pixel in other embodiment. Sectional drawing of the focus detection pixel in other embodiment.

  As an imaging apparatus according to an embodiment, a lens interchangeable digital still camera system will be described as an example. FIG. 1 is a diagram showing an outline of a camera system (digital still camera) 201 according to an embodiment. An interchangeable lens 202 is attached to the front portion of a camera body (camera body) 203. A mounting portion 221 for mounting the image sensor unit 400 is provided on the back of the camera body 203. The mounting unit 221 is provided with an electrical contact 222 for communicating with the image sensor unit 400 when the image sensor unit 400 is mounted on the mounting unit 221. The image sensor unit 400 can be attached to and detached from the mounting part 221 of the camera body 202, and when the image sensor unit 400 is mounted on the mounting part 221, an electrical contact 422 that contacts an electrical contact 222 for communicating with the camera body 203. Is provided.

  FIG. 2 is a block diagram illustrating a configuration of the camera system 201 according to the embodiment. The camera system 201 includes an interchangeable lens 202, a camera body 203, and an image sensor unit 400, and the interchangeable lens 202 is attached to the camera body 203 via a mount unit 204. An interchangeable lens 202 having various photographing optical systems can be attached to the camera body 203 via a mount unit 204. Further, the image sensor unit 400 is attached to the camera body 203 via the attachment portion 221. An image sensor unit 400 having various image sensors can be mounted on the camera body 203 via a mounting portion 221.

  The interchangeable lens 202 includes a lens 209, a zooming lens 208, a focusing lens 210, an aperture 211, a lens control device 206, and the like. The lens control device 206 includes a microcomputer (not shown), a memory, a drive control circuit, and the like, and performs drive control for adjusting the focus of the focusing lens 210 and adjusting the aperture diameter of the aperture 211, zooming lens 208, and focusing lens. In addition to detecting the state of 210 and the aperture 211, lens information is transmitted and camera information is received through communication with a body control device 214 described later. The aperture 211 forms an aperture having a variable aperture diameter at the center of the optical axis in order to adjust the amount of light and the amount of blur.

  The image sensor unit 400 includes an image sensor 412, a unit control device 401, a memory 402, an image sensor drive circuit 404, and the like. In an image sensor unit including an image sensor including a focus detection pixel, a pixel interpolation circuit 403 for interpolating virtual image pixel data at the position of the focus detection pixel from image data around the focus detection pixel is also provided. I have.

  The unit control device 401 drives and controls the image sensor 412 via the image sensor drive circuit 404, repeatedly reads out the image pixel data (image signal) and the focus detection pixel data (focus detection signal), and also via the electrical contact 422. By communicating with the body control device 214, the imaging pixel data and the focus detection pixel data lens information are transmitted to the camera body 203 and the camera body information is received from the camera body 203. The memory 402 stores characteristic information of the image sensor and information related to focus detection. The information is read by the unit control device 401 and transmitted to the camera body 203.

  The imaging element 412 has imaging pixels arranged in a two-dimensional manner, and in an imaging element including a focus detection pixel, the focus detection pixel is incorporated in a portion corresponding to the focus detection position. Details of the image sensor 412 will be described later.

  The camera body 203 includes a body control device 214, a liquid crystal display element driving circuit 215, a liquid crystal display element 216, an eyepiece lens 217, a memory card 219, an operation means 220, and the like. The body control device 214 includes a microcomputer, a memory, a drive control circuit, and the like. The body control device 214 generates an image and records image data of the image, and also generates focus information and generates the focus information based on the focus information. Repeat the focus adjustment. It also controls the overall camera system operation. The body control device 214 communicates with the lens control device 206 via the electrical contact 213 to receive lens information and transmit camera information (defocus amount, aperture value, etc.), and via the electrical contact 222. It communicates with the image sensor unit 422, receives characteristic information of the image sensor and information related to focus detection, and transmits camera body information.

  The liquid crystal display element 216 functions as an electric view finder (EVF). The liquid crystal display element driving circuit 215 displays an image on the liquid crystal display element 216, and the photographer can observe the image through the eyepiece lens 217. The memory card 219 is an image storage that stores image data. The operation unit 220 is a unit for transmitting the user's will to the camera body 203, whereby the focus detection position is selected and the shutter release is instructed.

  In the imaging element 412, imaging pixels are two-dimensionally arranged, and focus detection pixels are incorporated in portions corresponding to focus detection positions. Details of the image sensor 412 will be described later.

  With the above configuration, the following operation is performed. A subject image is formed on the light receiving surface of the image sensor 412 by the light beam that has passed through the interchangeable lens 202. This subject image is photoelectrically converted by the imaging element 412 to generate imaging pixel data and focus detection pixel data. The virtual imaging pixel data at the position of the focus detection pixel data is subjected to pixel interpolation by the pixel interpolation circuit 403. Image pickup pixel data including pixel interpolated data, focus detection pixel data, image sensor characteristic information, and information related to focus detection are taken into the unit control device 401 and transmitted to the body control device 214 by communication.

  The body control device 214 calculates a defocus amount based on the focus detection pixel data and information related to focus detection, and sends the defocus amount to the lens control device 206. The body control device 214 generates image data by processing the imaging pixel data in accordance with the characteristic information of the imaging element, stores the image data in the memory card 219, and drives the liquid crystal display element. The image is sent to the circuit 215 and an image is displayed on the liquid crystal display element 216. Further, the body control device 214 sends aperture control information to the lens control device 206 to control the aperture of the aperture 211.

  The lens control device 206 updates the lens information according to the focusing state, zooming state, aperture setting state, aperture opening F value, and the like. Specifically, the position of the zooming lens 208, the position of the focusing lens 210, and the aperture value (aperture diameter) of the aperture 211 are detected, and lens information is calculated according to these lens location and aperture value, or Lens information corresponding to the lens position and aperture value is selected from a lookup table prepared in advance, and the information is transmitted to the body control device 203.

  The lens control device 206 calculates a lens driving amount based on the received defocus amount, and drives the focusing lens 210 to the in-focus position according to the lens driving amount. In addition, the lens control device 206 drives the diaphragm 211 in accordance with the received diaphragm value.

  The power source may be built in the camera body 203 and supplied to the interchangeable lens 202 and the image sensor unit 400 via the mount unit 204 and the mounting unit 221, or the camera body 203, the interchangeable lens 202, and the image sensor unit 400. It may be built in each one.

  FIG. 3 is a diagram showing a focus detection position on the shooting screen in one type of image sensor unit A, and an image is sampled on the shooting screen when a focus detection pixel column on the image sensor 412 described later performs focus detection. An example of a region (focus detection area, AF area, focus detection position) to be performed is shown. In this example, focus detection areas 101 to 103 are arranged at the center and three left and right positions on the rectangular shooting screen 100. In the longitudinal direction of the focus detection area indicated by the rectangle, the focus detection pixels are linearly arranged in the vertical direction.

  Before describing the detailed configuration of the image sensor 412, the principle of a pupil division type phase difference detection method, which is a known technique, will be described with reference to FIG. A plurality of focus detection pixels 111 are arranged on the imaging surface 110. The focus detection pixel 111 includes a microlens 112 and a pair of photoelectric conversion units 113 and 114. The pair of photoelectric conversion units 113 and 114 are projected by the microlens 112 onto the distance measuring pupil plane 120 at a distance d (distance pupil distance) ahead from the imaging surface 110 to form the distance measuring pupils 123 and 124. In other words, the luminous flux of the ranging pupil 123 out of the luminous flux passing through the distance measuring pupil plane 120 at a distance d ahead of the imaging surface 110 is received by the photoelectric conversion unit 113 of the focus detection pixel 111, and the distance measuring pupil plane. Among the light beams that pass on 120, the light beam of the distance measuring pupil 124 is received by the photoelectric conversion unit 114 of the focus detection pixel 111. The relative shift amount (phase difference, image shift amount) between the image signal of the photoelectric conversion unit 113 in the array of the focus detection pixels 111 and the image signal of the photoelectric conversion unit 114 is an image on the imaging surface. Since it changes according to the focus adjustment state of the optical system to be formed, the focus adjustment state of the optical system can be detected by calculating this shift amount by processing a pair of image signals generated by the focus detection pixels. .

  By the way, the pair of distance measurement pupils 123 and 124 do not have a distribution obtained by simply projecting the pair of photoelectric conversion units 113 and 114, but the light diffraction effect according to the aperture diameter (substantially coincides with the pixel size) of the microlens 111. Due to this, the distribution is blurred and has a base. In FIG. 3, when the pair of distance measurement pupils 123 and 124 are scanned in the alignment direction using the slit in the direction perpendicular to the alignment direction of the pair of distance measurement pupils 123 and 124, a pair of distance measurement pupil distributions 133 and 134 are obtained. . Due to the diffraction effect, the pair of distance measuring pupil distributions 133 and 134 have overlapping portions 135 at adjacent portions.

  As described above, in the pupil division type phase difference detection method, the image displacement amount on the imaging surface of the pair of images formed by the light flux passing through the pair of distance measurement pupils is detected and converted into the image displacement amount with a predetermined conversion. Multiply by a coefficient to convert to a defocus amount (focus adjustment state) in the optical axis direction.

  FIG. 5 is a front view showing a detailed configuration of the image sensor 412, and shows the details of the pixel arrangement by enlarging the vicinity of the focus detection area 101 in FIG. 3. Imaging pixels 310 are densely arranged in a two-dimensional square lattice pattern on the imaging element 412. The imaging pixel 310 includes a red pixel (R), a green pixel (G), and a blue pixel (B), and is arranged according to a Bayer arrangement rule. For focus detection, focus detection pixels 313 and 314 for vertical focus detection having the same pixel size as the imaging pixels are alternately arranged on a vertical straight line on which green and blue pixels should be continuously arranged. Arranged consecutively.

  FIG. 6 is a diagram showing the shape of the microlens of the image pickup pixel and the focus detection pixel. The microlens 9 is originally cut out from a circular microlens 9 larger than the pixel size into a square shape corresponding to the pixel size. The cross section in the direction of the diagonal line passing through the optical axis of the lens 10 and the cross section in the direction of the horizontal line passing through the optical axis of the microlens 10 have shapes shown in the drawing.

  As shown in FIG. 7, the imaging pixel 310 includes a rectangular microlens 10, a photoelectric conversion unit 11 whose light receiving area is limited by a light shielding mask described later, and a color filter (not shown). There are three types of color filters, red (R), green (G), and blue (B), and the respective spectral sensitivities have the characteristics shown in FIG. In the image pickup element 412, the image pickup pixels 310 including the respective color filters are arranged in a Bayer array.

  As shown in FIG. 8A, the focus detection pixel 313 includes a rectangular microlens 10, a photoelectric conversion unit 13 whose light receiving area is limited by a light shielding mask described later, and an ND filter (neutral density filter) (not shown). The shape of the photoelectric conversion unit 13 that is configured and whose light-receiving area is limited by the light-shielding mask is rectangular. Further, as shown in FIG. 8B, the focus detection pixel 314 includes a rectangular microlens 10, a photoelectric conversion unit 14 whose light receiving area is limited by a light shielding mask described later, and an ND filter (not shown). The shape of the photoelectric conversion unit 14 in which the light receiving area is limited by the light shielding mask is rectangular. When the focus detection pixel 313 and the focus detection pixel 314 are displayed with the microlens 10 superimposed, the photoelectric conversion units 13 and 14 whose light receiving areas are limited by the light shielding mask are arranged in the vertical direction.

  The focus detection pixels 313 and 314 are not provided with a specific color filter in order to perform focus detection for all colors, but instead are provided with an ND filter that reduces the amount of incident light. The characteristics shown in FIG. In other words, the spectral characteristics are obtained by adding the spectral characteristics of the green pixel, red pixel, and blue pixel shown in FIG. 9, and the light wavelength region of the sensitivity includes the light wavelength regions of the sensitivity of the green pixel, red pixel, and blue pixel. ing. The density of the ND filter is determined so that, for example, the output level of the focus detection pixel is 3/4 or less of the output level of the green pixel when the image sensor is exposed to white light. This is a case where the vignetting of the focus detection light beam occurs in the region where the image height on the screen is high (focus detection areas 102 and 103), the output balance of the pair of focus detection pixels is lost, and the output of one focus detection pixel increases. This is because there is a margin so as not to exceed the output level of the imaging pixel (green pixel).

  The focus detection pixels 313 and 314 are arranged in a column where B and G of the imaging pixel 310 should be arranged. The focus detection pixels 313 and 314 are arranged in the column where the B and G of the imaging pixel 310 are to be arranged because an interpolation error occurs in the interpolation processing for obtaining an image signal for imaging at the position of the focus detection pixel. When this occurs, the interpolation error of the blue pixel is less noticeable than the interpolation error of the red pixel due to human visual characteristics.

  The imaging pixel 310 is designed in such a shape that the microlens 10 receives all the light flux that passes through the exit pupil of the brightest interchangeable lens (for example, F1.0). The focus detection pixels 313a and 314a are designed in such a shape that the microlens 10 receives light beams that pass through a pair of predetermined regions of the exit pupil of the interchangeable lens.

  FIG. 11 is a cross-sectional view of the imaging pixel 310. In the imaging pixel 310, a light shielding mask 30 is formed in proximity to the photoelectric conversion unit 11 for imaging, and the light beam conversion unit 11 receives light that has passed through the opening 30 a of the light shielding mask 30. A planarizing layer 31 is formed on the light shielding mask 30, and a color filter 38 is formed thereon. A planarizing layer 32 is formed on the color filter 38, and the microlens 10 is formed thereon. The shape of the opening 30 a is projected forward by the microlens 10. The photoelectric conversion unit 11 is formed on the semiconductor circuit substrate 29.

  FIG. 12 is a cross-sectional view of the focus detection pixels 313 and 314. In the focus detection pixels 313 and 314, a light shielding mask 30 is formed in proximity to the focus detection photoelectric conversion units 13 and 14, and light that has passed through the openings 30 b and 30 c of the light shielding mask 30 is converted into the light beam conversion units 13 and 14. Receive light. A planarizing layer 31 is formed on the light shielding mask 30, and an ND filter 34 is formed thereon. A planarizing layer 32 is formed on the ND filter 34, and the microlens 10 is formed thereon. The shapes of the openings 30b and 30c are projected forward by the microlens 10. The photoelectric conversion units 13 and 14 are formed on the semiconductor circuit substrate 29.

  FIG. 13 shows a configuration of a pupil division type phase difference detection type focus detection optical system using a microlens. The focus detection pixel portion is shown in an enlarged manner. In the figure, reference numeral 90 denotes an exit pupil set at a distance d forward from the microlens arranged on the planned imaging plane of the interchangeable lens 202 (see FIG. 1). This distance d is a distance determined according to the curvature and refractive index of the microlens, the distance between the microlens and the photoelectric conversion unit, and is referred to as a distance measuring pupil distance in this specification. Reference numeral 91 is an optical axis of the interchangeable lens, 10 is a microlens, 13 and 14 are photoelectric conversion units, 313 and 314 are focus detection pixels, 71 is a photographing light beam, and 73 and 74 are focus detection light beams.

  Reference numeral 93 denotes an area of the opening 30b projected by the microlens 10, which is called a distance measuring pupil in this specification. Similarly, 94 is an area of the opening 30 c projected by the microlens 10. In FIG. 13, the regions 93 and 94 are shown for ease of explanation, but actually, the shape of the opening 30b is enlarged and projected and becomes a blurred shape due to diffraction.

  FIG. 13 schematically illustrates five focus detection pixels adjacent to the photographing optical axis. However, in the focus detection pixel array at the periphery of the screen, each photoelectric conversion unit has corresponding distance measurement pupils 93 and 94, respectively. Are configured to receive a light beam coming to each microlens. The arrangement direction of the focus detection pixels is made to coincide with the arrangement direction of the pair of distance measuring pupils, that is, the arrangement direction of the pair of photoelectric conversion units.

  The microlens 10 is disposed in the vicinity of the planned imaging plane of the interchangeable lens 202 (see FIG. 2), and the shapes of the openings 30b and 30c disposed near the photoelectric conversion units 13 and 14 by the microlens 10 are micro. The projection is performed on the exit pupil 90 separated from the lens 10 by the distance measurement pupil distance d, and the projection shape forms distance measurement pupils 93 and 94.

  The photoelectric conversion unit 13 outputs a signal corresponding to the intensity of the image formed on the microlens 10 by the light beam 73 passing through the distance measuring pupil 93 and directed to the microlens 10 of the focus detection pixel 313. Further, the photoelectric conversion unit 14 outputs a signal corresponding to the intensity of the image formed on the microlens 10 by the light flux 74 that passes through the distance measuring pupil 94 and travels toward the microlens 10 of the focus detection pixel 314.

  A large number of the two types of focus detection pixels described above are arranged in a straight line, and the output of the photoelectric conversion unit of each pixel is grouped into a distance measurement pupil 93 and an output group corresponding to the distance measurement pupil 94, thereby measuring the distance measurement pupil 93 and the measurement pupil 93. Information on the intensity distribution of the pair of images formed on the pixel array by the focus detection light beams that respectively pass through the distance pupil 94 is obtained. By applying an image shift detection calculation process (correlation calculation process, phase difference detection process), which will be described later, to this information, an image shift amount of a pair of images is detected by a so-called pupil division type phase difference detection method. Furthermore, by performing a conversion calculation according to the proportional relationship between the distance between the center of gravity of the pair of distance measurement pupils and the distance measurement pupil distance to the image shift amount, the current image formation surface (the position of the microlens array) ( A deviation (defocus amount) of an actual imaging plane at a focus detection position determined on the photographing screen 100 is calculated.

  FIG. 14 is a diagram for explaining the state of the imaging light beam received by the imaging pixel 310 of the imaging element 412 shown in FIG. 7 in comparison with FIG. 11, and a description of portions overlapping those in FIG. 13 is omitted. The imaging pixel includes a microlens 10 and a photoelectric conversion unit 11 disposed behind the microlens 10, and the shape of the opening 30 a disposed in the vicinity of the photoelectric conversion unit 51 is separated from the microlens 10 by the distance measurement pupil distance d. The projected shape is projected onto the exit pupil 90, and the projected shape forms a region 95 that is substantially circumscribed by the distance measuring pupils 93 and 94.

  The photoelectric conversion unit 11 outputs a signal corresponding to the intensity of the image formed on the microlens 11 by the imaging light flux 71 that passes through the region 95 and travels toward the microlens 10.

  There are a plurality of variations of the image sensor unit including different image sensors. FIG. 15 is a diagram showing a focus detection position on the shooting screen in one type of image sensor unit B, and a region where the focus detection pixel row on the image sensor 412 samples an image on the shooting screen when focus detection is performed. An example of (focus detection area, focus detection position) is shown. In this example, focus detection areas 141 to 143 are arranged at the center and three places on the left and right on the rectangular shooting screen 140. In the longitudinal direction of the focus detection area indicated by the rectangle, the focus detection pixels are linearly arranged in the vertical direction. The size of the imaging screen 110 is smaller than the imaging screen 100 (FIG. 3) of the imaging device of the imaging device unit A.

  FIG. 16 is a front view showing a detailed configuration of the image sensor 412, and shows the details of the pixel arrangement by enlarging the vicinity of the focus detection area 141 in FIG. In the imaging element 412, imaging pixels 320 are densely arranged in a two-dimensional square lattice. The imaging pixel 320 includes a red pixel (R), a green pixel (G), and a blue pixel (B), and is arranged according to a Bayer arrangement rule. For focus detection, vertical focus detection focus detection pixels 313 and 314 having the same pixel size as that of the imaging pixel 320 are alternately arranged on the vertical straight line on which the green pixel and the blue pixel should be continuously arranged. Are arranged in succession. The pixel size of the imaging pixel 320 is smaller than the imaging pixel 310 (FIG. 5) of the imaging element of the imaging element unit A.

  FIG. 17 is a diagram illustrating a focus detection position on the shooting screen in one type of image sensor unit C, and a region in which the focus detection pixel row on the image sensor 412 samples an image on the shooting screen when focus detection is performed. An example of (focus detection area, focus detection position) is shown. In this example, focus detection areas 151 to 155 are arranged at five locations in the center and diagonal directions on the rectangular shooting screen 100. In the central focus detection area 151, focus detection pixels are linearly arranged in the vertical direction in the longitudinal direction of the focus detection area indicated by a rectangle. In the focus detection areas 152 to 155 arranged in the diagonal area of the screen, the focus detection pixels are linearly arranged in a 45-degree oblique direction in the longitudinal direction of the focus detection area indicated by a rectangle. The size of the imaging screen 100 is the same as the imaging screen 100 (FIG. 3) of the imaging device of the imaging device unit A.

  FIG. 18 is a front view showing a detailed configuration of the image sensor 412, and shows the details of the pixel arrangement by enlarging the vicinity of the focus detection area 153 in FIG. In the imaging element 412, imaging pixels 320 are densely arranged in a two-dimensional square lattice. The imaging pixel 310 includes a red pixel (R), a green pixel (G), and a blue pixel (B), and is arranged according to a Bayer arrangement rule. For focus detection, vertical focus detection focus detection pixels 333 and 334 having the same pixel size as that of the image pickup pixel 310 are alternately arranged. Arranged continuously on top. The pixel size of the image pickup pixel 310 is the same as that of the image pickup pixel 310 (FIG. 5) of the image pickup element of the image pickup element unit A.

  FIG. 19 is a diagram showing a focus detection position on the photographing screen in one type of image sensor unit D, and no focus detection pixel column is present on the image sensor 412. The size of the imaging screen 100 is the same as the imaging screen 100 (FIG. 3) of the imaging device of the imaging device unit A.

  FIG. 20 is a front view showing a detailed configuration of the image sensor 412, and shows the details of the pixel arrangement by enlarging the vicinity of the center in FIG. In the imaging element 412, imaging pixels 320 are densely arranged in a two-dimensional square lattice. The imaging pixel 320 includes a red pixel (R), a green pixel (G), and a blue pixel (B), and is arranged according to a Bayer arrangement rule. The pixel size of the image pickup pixel 320 is the same as that of the image pickup pixel 310 (FIG. 5) of the image pickup element of the image pickup element unit A.

  21, 22, and 23 are flowcharts illustrating operations of the body control device 214, the unit control device 401, and the lens control device 206 of the camera system 201 (digital still camera, imaging device) according to an embodiment. In FIG. 21, when the camera is turned on in step S100, the body control device 214 starts an imaging operation after step S110.

  In step S105, it is checked whether or not the interchangeable lens 202 is attached to the camera body 203. If the interchangeable lens 202 is not attached, the interchangeable lens 202 is awaited, and if attached, communicates with the lens control device 206. Lens information (aperture aperture F value, etc.) is read out.

  In step S110, it is checked whether or not the image sensor unit 400 is attached to the camera body 203. If the image sensor unit 400 is not attached, the camera waits for the image sensor unit 400 to be attached. The image sensor unit information stored in the memory 402 is read through communication.

Details of the image sensor unit information will be described here. Tables 1 and 2 are tables that list image sensor unit information. Table 1 is information related to focus detection, and Table 2 is characteristic information of the image sensor. Tables 1 and 2 show data of the image sensor units A, B, C, and D in which the image sensors described with reference to FIGS. 3, 5, and 15 to 20 are mounted.

  In Table 1, “AF pixel presence / absence” is information indicating whether or not a focus detection pixel is included in the image sensor, the image sensor units A, B, and C are “present”, and the image sensor unit D is “ None ”. The image sensor unit D has no information related to subsequent focus detection. The “number of AF areas” is information indicating the number of AF areas (focus detection areas) on the image sensor, the image sensor units A and B are “3”, and the image sensor unit C is “5”.

  The AF areas on the image sensor are numbered. For example, in FIG. 3, 101 is area 1, 102 is area 2, and 103 is area 3. “Area 1 position (row)” and “Area 1 position (column)” are information indicating the position of area 1 on the image sensor by the number of rows and columns of the pixel array, and image sensor units A, B, and C are It is as shown in Table 1. Here, the position of area 1 is appropriately determined as the position of the center pixel in the focus detection pixel array or the position of the first pixel in the focus detection pixel array.

  “Area 1 AF pixel count” is information indicating the number of focus detection pixels in area 1 on the image sensor, and the image sensor units A, B, and C are as shown in Table 1. “Number of area 1 AF pixels PD (photodiodes)” is information indicating the number of photoelectric conversion units provided in one focus detection pixel in area 1 on the image sensor, and image sensor units A, B, and C are “1”. "It has become. In a modified example as will be described later, there are cases where it becomes “2” depending on the structure of the focus detection pixel.

  “Area 1 AF pixel array direction” is information indicating the array direction of focus detection pixels in area 1 on the image sensor, and image sensor units A, B, and C are “vertical”. Depending on the arrangement direction of the AF area, it becomes “horizontal”, “obliquely rising 45 degrees”, and “obliquely rising 45 degrees”. “Area 1 AF pixel detection pitch” is information indicating the image detection pitch of the focus detection pixel in area 1 on the image sensor in μm units, “8” for image sensor unit A, “6” for image sensor unit B, The element unit C is “8”. In the area 1 of the image sensor units A, B, and C, a pair of focus detection pixels are alternately arranged in the vertical direction, and the detection pitch is an interval between the pair of focus detection pixels, and the value is 2 of the pixel pitch. Double the value. When the arrangement direction of the focus detection pixels of the image sensor unit C is oblique, this value is further multiplied by √2.

  “Area 1 AF pixel color filter” is information indicating whether or not the focus detection pixel in area 1 on the image sensor has a color filter and what color filter the image sensor unit has. C is “None”. When the focus detection pixel includes a green color filter, the color is “green”. “Area 1 distance pupil distance” is information indicating the distance distance pupil distance (see FIG. 13) of the focus detection pixels in area 1 on the image sensor, and image sensor units A, B, and C are as shown in Table 1. ing.

“Area 1F1.0 conversion coefficient”, “Area 1F1.4 conversion coefficient”, “Area 1F2.0 conversion coefficient” to “Area 1F8.0 conversion coefficient” are the data of the focus detection pixel array of area 1 on the image sensor. This is information indicating a conversion coefficient when converting an image shift amount into a defocus amount with each F value when performing a focus detection calculation to be described later, and the imaging element units A, B, and C are as shown in Table 1. Yes. Hereinafter, the same information as in area 1 also exists in area 2 and subsequent areas.

  In Table 2, “pixel arrangement” is information indicating the pixel arrangement of the image sensor, and the image sensor units A, B, C, and D are “square lattices”. Depending on the pixel arrangement of the image sensor, it may be a “hexagonal lattice”. “Number of pixels (horizontal)” and “number of pixels (vertical)” are information indicating the number of pixels on the image sensor in the horizontal direction and the vertical direction, and the image sensor units A, B, C, and D are as shown in Table 1. It has become. “Pixel size” is information indicating the pixel size of the imaging pixel in μm units, and is “4” for the imaging element units A, C, and D, and “3” for the imaging element unit B. The “color filter” is information indicating the configuration of the color filter of the imaging pixel, and is “RGB” in the imaging element units A, B, C, and D. Depending on the configuration of the color filter of the image sensor, it may be “complementary color YCM”, “monochrome”, or “infrared”. “Filter arrangement” is information indicating the configuration of the color filter of the image pickup pixel, and is “Bayer” in the image pickup device units A, B, C, and D.

  The “read mode” is information indicating the read mode of the pixel output of the image sensor, and is “normal / high speed” in the image sensor units A, B, C, and D. This indicates that there are a mode for reading pixel output from the image sensor at a normal speed and a mode for reading pixel output at a high speed. “Horizontal thinning”, “vertical thinning”, “horizontal addition”, and “vertical addition” are the horizontal direction when thinned out and read out the pixel output from the image sensor, the horizontal direction when thinned out and read out by adding the pixels in the vertical direction, This is information indicating the number of pixels added in the vertical direction, and the image sensor units A, B, C, and D are as shown in Table 1.

  “Dynamic range” and “sensitivity” are information representing the dynamic range and sensitivity of the imaging pixel in numerical values, and the imaging element units A, B, C, and D are as shown in Table 1. “Defective pixel position information” is information indicating the number of defective pixels / defective pixel positions (rows, columns) for all defective pixels. “PRNU information” is information indicating sensitivity non-uniformity (Phot-Response-Non-Uniformity) of all pixels (imaging pixels, focus detection pixels) for all pixels. “DSNU information” is information indicating dark current non-uniformity (Dark-Signal-Non-Uniformity) of all pixels (imaging pixels, focus detection pixels) for all pixels.

  Returning to FIG. 21, the description will be continued. In step S120, the imaging pixel data is read from the imaging element unit 400, and the imaging pixel data is subjected to image processing based on the characteristic information of the imaging element obtained in step S110 to generate image data. Examples of image processing include debayer processing (processing for converting RAW data of imaging pixel data into RGB data), compression / format conversion processing such as JPEG image generation, γ conversion processing, and white balance processing.

  In step S130, an image is displayed on the electronic viewfinder based on the image data. In step S140, based on the information regarding focus detection obtained in step S110, it is determined whether the image sensor has a focus detection pixel (has a focus detection function). The focus detection calculation process in steps S150 to S180 is skipped and the process proceeds to step S190.

  When the focus detection pixel is provided, in step S150, based on the information related to focus detection obtained in step S110, the focus detection area (focus detection position) is displayed on the electronic viewfinder so as to be superimposed on the image. In step S160, focus detection pixel data is read from the image sensor unit 400, and an image shift detection calculation described later is performed based on the focus detection pixel data to calculate a defocus amount. It is assumed that the photographer has previously selected a desired focus detection area on the imaging surface using an operation member for selecting a focus detection area.

  In step S170, it is checked whether or not the focus is close, that is, whether or not the calculated absolute value of the defocus amount is within a predetermined value. If it is determined that the focus is not close, the process proceeds to step S180, the defocus amount is transmitted to the lens controller 206, and the focusing lens 210 of the interchangeable lens 202 is driven to the focus position. Then, it returns to step S105 and repeats the operation | movement mentioned above. Even when focus detection is impossible, the process branches to this step, a scan drive command is transmitted to the lens control device 206, and the scan driving of the focusing lens 210 of the interchangeable lens 202 is started from infinity to the nearest. Then, it returns to step S105 and repeats the operation | movement mentioned above.

  If it is determined in step S170 that the focus is close to the in-focus state, the process proceeds to step S190, and it is determined whether or not a shutter release has been performed by operating a shutter button (operation member). If it is determined that the shutter release has not been performed, the process returns to step S105, and the above-described operation is repeated. On the other hand, if it is determined that the shutter release has been performed, the process proceeds to step S200, where an aperture adjustment command is transmitted to the lens control device 206, and the aperture value of the interchangeable lens 202 is set to the control F value (the F value set by the photographer or automatically). ). After the aperture control is completed, the imaged pixel data is read from the image sensor unit 400, and the imaged pixel data is processed based on the image sensor characteristic information obtained in step S110 to generate image data. In the subsequent step S210, the image data is stored in the memory card 219, and the process returns to step S105 to repeat the above-described operation.

  In FIG. 22, when the power is turned on in step S400, the unit control device 401 starts the operation after step S410. In step S410, it is checked whether an information read request is received from the body control device 214. If there is an information request, the information specified in step S420 is transmitted to the body control device 214. The above operation is repeated.

  In FIG. 23, when the power is turned on in step S600, the lens control device 206 starts the operation after step S610. In step S610, it is checked whether an information read request is received from the body control device 214. If there is an information request, the information specified in step S620 is transmitted to the body control device 214.

  In step S630, it is checked whether control information (aperture value, defocus amount) is received from the body control device 214. If control information is received, control corresponding to the control amount is performed in step S640. When the control information is an aperture value, the aperture aperture shape is controlled to be the aperture value. When the control information is a defocus amount, a lens drive amount corresponding to the defocus amount is calculated, and focusing driving is performed according to the drive amount. The above operation is repeated.

Details of the image shift detection calculation process (correlation calculation process) in step S160 in FIG. 21 will be described below. The pair of images detected by the focus detection pixels has a possibility that the distance measurement pupil is displaced by the aperture of the lens and the balance of the light quantity is lost. Perform the operation. For the focus detection pixel data read from the image sensor unit 400, that is, a pair of data strings (A1 _{1 to} A1 _M , A2 _{1 to} A2 _M : M is the number of data), the applicant's application (Japanese Patent Laid-Open No. 2007-333720). The correlation calculation (formula (1)) disclosed in (1) is performed to calculate the correlation amount C (k).
C (k) = Σ | A1 _n · A2 _{n + 1 + k−} A2 _{n + k} · A1 _{n + 1} | (1)

In equation (1), Σ operations are n = 1,. . . , M are accumulated. The range taken by n is limited to a range in which data of A1 _n , A1 _{n + 1} , A2 _{n + k} , A2 _{n + 1 + k} exists according to the image shift amount k. The image shift amount k is an integer and is a relative shift amount with the data interval of the data string as a unit.

As shown in FIG. 24A, the calculation result of the expression (1) indicates that the correlation amount C (k) at an image shift amount (k = k _j = 2 in FIG. 24A) having a high correlation between a pair of data. Becomes minimal (the smaller the value, the higher the degree of correlation). The shift amount x that gives the minimum value C (x) with respect to the continuous correlation amount is obtained using the three-point interpolation method according to equations (2) to (5).
x = k _j + D / SLOP (2)
C (x) = C (k _j ) − | D | (3)
D = {C (k _j −1) −C (k _j +1)} / 2 (4)
SLOP = MAX {C ( _kj + 1) -C ( _kj ), C ( _kj- 1) -C ( _kj )}
(5)

Whether the shift amount x calculated by the equation (2) is reliable is determined as follows. As shown in FIG. 24B, when the degree of correlation between a pair of data is low, the value of the minimal value C (x) of the interpolated correlation amount is large. Therefore, when C (x) is equal to or greater than a predetermined threshold value, it is determined that the reliability of the calculated shift amount is low, and the calculated shift amount x is canceled.
Alternatively, in order to normalize C (x) with the contrast of data, when the value obtained by dividing C (x) by SLOP that is proportional to the contrast is equal to or greater than a predetermined value, the reliability of the calculated shift amount Is determined to be low, and the calculated shift amount x is canceled. Alternatively, when SLOP that is a value proportional to the contrast is equal to or less than a predetermined value, it is determined that the subject has low contrast and the reliability of the calculated shift amount is low, and the calculated shift amount x is canceled.

As shown in FIG. 24C, when the degree of correlation between the pair of data is low and there is no drop in the correlation amount C (k) between the shift ranges k _{min to} k _max , the minimum value C (x) is obtained. In such a case, it is determined that the focus cannot be detected. When it is determined that the calculated shift amount x is reliable, it is converted into the image shift amount shft by the equation (6).
shft = PY · x (6)

In Expression (6), PY is an AF pixel detection pitch which is one of information related to focus detection read from the image sensor unit 400. The image shift amount calculated by the equation (6) is multiplied by the conversion coefficient _Kd to convert to the defocus amount def.
def = K _d · shft (7)

Here, the conversion coefficient _Kd is a conversion coefficient corresponding to the F value of the aperture opening included in the lens information, among the conversion coefficients corresponding to the F value included in the information related to the focus detection read from the image sensor unit 400. .

  As described above, in the embodiment of the present invention, the image sensor unit is exchanged with respect to the camera body, and is provided so as to be detachable. Information related to focus detection of the image sensor unit from the image sensor unit to the camera body is also provided. Since the focus detection pixel data is transmitted, it is possible to control the focus adjustment operation including complicated focus detection calculation on the camera body main body side, and the processing load on the image sensor unit side can be reduced.

  Further, the process of interpolating the data of the virtual imaging pixel at the focus detection pixel position based on the data of the imaging pixels around the focus detection pixel is performed by the dedicated pixel interpolation circuit 403 on the imaging element unit side, thereby performing AF. Pixel interpolation that needs to be based on parameters that are difficult to predict the AF area layout of an image sensor that comes out later than the camera body, such as area layout, and that processing speed is insufficient in software processing In addition to being able to perform at a high speed, the image sensor element characteristic information and image pixel data are transmitted from the image sensor unit to the camera body body, and general-purpose image processing is performed on the camera body body side. The processing burden can be reduced.

  For the user, the desired focus detection function can be utilized just by replacing and mounting an image sensor unit equipped with various image sensors with different focus detection functions, and a plurality of camera bodies are prepared. Such a burden is eliminated.

<< Other Embodiments of the Invention >>
25 and 26 are flowcharts showing the operations of the body control device 214 and the unit control device 401 of the camera system (digital still camera, imaging device) according to another embodiment of the present invention. In this embodiment, information related to focus detection is transmitted from the camera body to the image sensor unit, the defocus amount is calculated on the image sensor unit side, and the calculated defocus amount is transmitted from the image sensor unit to the camera body. The camera body performs a focus adjustment operation based on the defocus amount.

FIG. 25 differs from FIG. 21 in steps S150 to S170, and only that portion will be described. In step S161, the body control device 214 transmits information related to focus detection to the unit control device 401.

  Table 3 is a table that lists information related to the focus detection. In Table 3, “aperture aperture F value” is information representing the aperture aperture diameter of the interchangeable lens as an F value, and “AF area designation number” designates the position of the AF area selected by the photographer on the camera body side. Information, specifically “AF area 1”, “AF area 2”,...

  In step S162, the body control device 214 receives the defocus amount of the designated AF area from the unit control device 401.

  In FIG. 26, when the power is turned on in step S400, the unit control device 401 starts the operation after step S410. In step S410, it is checked whether an information read request is received from the body control device 214. If there is an information request, the information specified in step S420 is transmitted to the body control device 214.

  In step S430, it is checked whether information (aperture value, AF area) related to focus detection is received from the body control device 214. If the information is received, the focus detection pixel corresponding to the AF area specified in step S640. An image shift amount is calculated based on the data, and the image shift is converted into a defocus amount by a conversion coefficient corresponding to the received aperture value. In step S450, the calculated defocus amount is transmitted to the body control device 214. The above operation is repeated.

  As described above, in the embodiment of the present invention, the image sensor unit is exchanged with respect to the camera body body and is detachably provided, and information relating to focus detection is transmitted from the camera body to the image sensor unit. A defocus amount is transmitted on the unit side based on the information and focus detection pixel data, the defocus amount is transmitted from the image sensor unit to the camera body, and a focus adjustment operation is performed on the camera body side based on the defocus amount. Because it is controlled, it is a parameter that has many variations, such as the specifications of focus detection pixels (AF area layout, AF pixel configuration), and it is difficult to predict the specifications of the focus detection pixels of image sensors that come out after the camera body. Focus detection calculation processing that must be performed based on the image sensor unit can be performed on the individual image sensor unit side. The need to transfer a large number of focus detection pixel data from the device unit in the camera main body is eliminated, it is possible to increase the speed of focus adjustment can reduce the overall processing time.

  The focus detection area layout in the image sensor mounted on the image sensor unit is not limited to FIGS. 3, 15, and 17, and there are various modifications. For example, as shown in FIG. 27, a large number of focus detection areas 104 may be arranged on the screen 100 at a high density as shown in the figure.

  In the partial enlarged view of the image sensor 412 illustrated in FIG. 5, an example in which each pixel includes a pair of focus detection pixels 313 and 314 having one photoelectric conversion unit is illustrated. However, a pair of photoelectric conversions is performed in one focus detection pixel. You may make it provide a part. FIG. 28 is a partially enlarged view of such an image sensor 412. The focus detection pixel 311 includes a pair of photoelectric conversion units. The focus detection pixel 311 illustrated in FIG. 29 performs a function corresponding to the pair of the focus detection pixel 313 and the focus detection pixel 314 illustrated in FIGS. The focus detection pixel 311 includes a microlens 10 and a pair of photoelectric conversion units 13 and 14 as shown in FIG. The focus detection pixel 311 is not provided with a color filter in order to increase the amount of light, and its spectral characteristic is a spectral that combines the spectral sensitivity of a photodiode that performs photoelectric conversion and the spectral characteristic of an infrared cut filter (not shown). Characteristics (see FIG. 10). In other words, the spectral characteristics are obtained by adding the spectral characteristics of the green pixel, red pixel, and blue pixel shown in FIG. 9, and the light wavelength region of the sensitivity includes the light wavelength regions of the sensitivity of the green pixel, red pixel, and blue pixel. ing.

  FIG. 30 is a cross-sectional view of the focus detection pixel 311 shown in FIG. 29, in which a light shielding mask 30 is formed in proximity to the photoelectric conversion units 13 and 14, and light that has passed through the opening 30 d of the light shielding mask 30 is reflected. The light beam converters 13 and 14 receive light. A planarizing layer 31 is formed on the light shielding mask 30, and an ND filter 34 is formed thereon. A planarizing layer 32 is formed on the ND filter 34, and the microlens 10 is formed thereon. The shape of the photoelectric conversion units 13 and 14 limited to the opening 30d by the microlens 10 is projected forward to form a pair of distance measuring pupils. The photoelectric conversion units 13 and 14 are formed on the semiconductor circuit substrate 29.

  In the image sensor according to the above-described embodiment, an example in which the imaging pixel includes a Bayer color filter is shown. However, the configuration and arrangement of the color filter are not limited thereto, and complementary color filters (green: G, yellow: The present invention can also be applied to an array other than the array of Ye, magenta: Mg, cyan: Cy) or a Bayer array.

  In the focus detection pixel in the embodiment described above, an example in which the opening shape of the light shielding mask is rectangular has been described. However, the opening shape of the light shielding mask is not limited thereto, and may be other shapes, for example, a semicircular shape, It can also be an ellipse or a polygon.

  When the image sensor unit 400 is attached to the camera body 203 in the above-described embodiment, the image sensor unit information reading process is executed in step S110 in FIG. 21, but the image sensor unit type (ID) can be identified in advance. The image sensor unit information may be stored in association with a unique identifier, and a detailed image sensor unit information read process may be executed inside the camera body 203 by receiving an ID from the mounted image sensor unit 400. .

  When the image sensor unit 400 attached to the camera body 203 in the above-described embodiment is the image sensor unit D, the focus detection calculation is skipped. In FIG. 21, after the negative determination in step S140, the contrast detection method is used. Thus, the focus detection calculation may be performed based on the imaging pixel data. When the negative determination is made in step S140, the focus detection calculation may be stopped, and a notification screen that prompts the user to adjust the focus manually is displayed on the liquid crystal display element 216.

  Note that the imaging apparatus is not limited to a digital still camera or a film still camera in which an interchangeable lens is mounted on the camera body as described above. For example, the present invention can be applied to a lens-integrated digital still camera, film still camera, or video camera. Furthermore, the present invention can be applied to a small camera module built in a mobile phone, a surveillance camera, a visual recognition device for a robot, an in-vehicle camera, and the like.

100, 140 Shooting screens 101-104, 141-143, 151-155 Focus detection area
201 Camera system (imaging device)
202 Interchangeable lens (shooting optical system)
203 Camera body (main body)
204 Mount unit 206 Lens control device 208 Zooming lens 209 Lens 210 Focusing lens 211 Apertures 213, 222, 422 Electric contact 214 Body control device (main body communication means)
215 Liquid crystal display element driving circuit 216 Liquid crystal display element (display)
217 Eyepiece 219 Memory card 220 Operation unit 221 Mounting unit 400 Image sensor unit 401 Unit control device (unit communication unit)
402 Memory 403 Pixel Interpolation Circuit 404 Image Sensor Drive Circuit 412 Image Sensor

Claims (13)

An image pickup device unit including an image pickup device having an image pickup pixel and a focus detection pixel, and unit communication means;
A mounting portion on which the image sensor unit is detachably mounted, a photographing optical system, and a main body including main body communication means;
The imaging pixel outputs an imaging signal,
The focus detection pixel outputs a focus detection signal for detecting a focus adjustment state of the photographing optical system,
When the image sensor unit is mounted on the mounting unit, the focus detection related to the detection of the focus adjustment state with the main body via the communication between the unit communication means and the main body communication means. An imaging device characterized by transmitting and receiving information. The imaging device according to claim 1,
The image sensor unit includes unit control means for detecting the focus adjustment state using the focus detection signal,
The imaging apparatus according to claim 1, wherein the focus detection related information is a defocus amount obtained by the unit control means detecting the focus adjustment state. The imaging device according to claim 1,
The focus detection signal is output to detect the focus adjustment state by a pupil division type phase difference detection method,
The imaging apparatus, wherein the focus detection related information is information indicating whether or not the imaging device includes a focus detection pixel that outputs the focus detection signal based on the pupil division type phase difference detection method. The imaging device according to claim 1,
The focus detection signal is output to detect the focus adjustment state by a pupil division type phase difference detection method,
The imaging device includes a focus detection area in which the focus detection pixels are arranged,
The focus detection related information includes information on the focus detection area, information on the focus detection signal and the number of focus detection pixels, or an interval between two paired focus detection pixels and the pupil division type phase difference. An imaging apparatus comprising at least one piece of information related to a conversion coefficient for converting an image shift amount detected by a detection method into a defocus amount. In the imaging device according to claim 2 or 4,
The imaging device includes a plurality of focus detection areas in which the focus detection pixels are arranged,
The main body includes designation means for designating one of the plurality of focus detection areas as a predetermined focus detection area,
The focus detection related information further includes at least one of information on the predetermined focus detection area specified by the specifying means and information on an aperture diameter of an aperture stop included in the photographing optical system. An imaging apparatus characterized by the above. In the imaging device according to any one of claims 1 to 5,
The main body includes an image generation unit that generates image data;
When the main body receives the characteristic information of the image pickup element and the image pickup signal output from the image pickup pixel from the image pickup element unit via the communication, the image generation unit is configured to use the image pickup signal based on the characteristic information. Processing, and generating the image data. A main body including a photographing optical system, a mounting portion, and main body communication means;
A first imaging element unit including an imaging element having an imaging pixel and a focus detection pixel and unit communication means;
A second imaging element unit including at least an imaging element having imaging pixels and unit communication means;
Each of the imaging pixels included in the first and second imaging element units outputs an imaging signal,
The focus detection pixel outputs a focus detection signal for detecting a focus adjustment state of the photographing optical system,
Each of the first and second image sensor units is alternatively detachably mounted on the mounting portion of the apparatus body,
The main body control means includes
When the first image sensor unit is mounted on the mounting portion, the first image sensor is communicated between the unit communication unit included in the first image sensor unit and the main body communication unit. When the first information related to the detection of the focus adjustment state with the unit is received and the second image sensor unit is mounted on the mounting unit, the second image sensor unit is included in the second image sensor unit. Receiving second information different from the first information through communication between the unit communication means and the main body communication means;
The imaging in which the focus adjustment state detection process is performed depending on whether the first imaging element unit or the second imaging element unit is attached to the attachment unit. apparatus. The imaging apparatus according to claim 7,
The image pickup device, wherein the image pickup element included in the second image pickup element unit does not have the focus detection pixel. The imaging apparatus according to claim 7,
The image sensor included in the second image sensor unit further includes the focus detection pixel,
The imaging element included in the first imaging element unit and the imaging element included in the second imaging element unit both have imaging surfaces having substantially the same shape,
The plurality of focus detection pixels included in the first image sensor unit are arranged in a predetermined focus detection area in the imaging surface of the image sensor,
The plurality of focus detection pixels included in the second image sensor unit are arranged in a focus detection area that is positionally different from the predetermined focus detection area in the imaging surface of the image sensor. An imaging device that is characterized. The imaging apparatus according to claim 7,
The first information is information indicating that the focus detection pixel is included in the first image sensor unit,
The main body control means performs a first detection process as the focus adjustment state detection process when the first information is received, and receives the first information when the first information is not received. An image pickup apparatus that performs a second detection process different from the process. The imaging device according to claim 10, further comprising a display,
The plurality of focus detection pixels included in the first image sensor unit are arranged in a focus detection area in an imaging surface of the image sensor,
The first information further includes position information of the focus detection area on the imaging surface,
The imaging apparatus, wherein the first detection process includes a display data output process for displaying a screen representing the position of the focus detection area on a display based on the position information. The imaging device according to claim 10.
The main body control means further receives the focus detection signal from the first image sensor unit via the communication, and the first detection based on the focus detection signal received from the first image sensor unit. When processing is performed and the first information is not received, it is the second image sensor unit that is mounted on the mounting portion, and is included in the second image sensor unit. The imaging device, wherein the imaging device determines that the focus detection pixel is not included, and performs the second detection process.   The first imaging device unit used in the imaging device according to any one of claims 7 to 12.

Images