JP2009162845A - Imaging device, focus detecting device and imaging apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To simplify the circuit configuration and control of an imaging device where a focus detecting pixel array is partly disposed in the two-dimensional arrays of imaging pixels. <P>SOLUTION: In the imaging device where the imaging pixels 310 for imaging an image formed by an optical system are two-dimensionally arrayed, first focus detecting elements 312 and second focus detecting elements 313 for detecting the focusing state of the optical system are partly and linearly arrayed by turns in place of the imaging pixels 310. The first focus detecting element 312 includes a first photoelectric conversion section for receiving light passing through one of a pair of areas of the exit pupil of the optical system through a microlens. The second focus detecting pixel 313 includes a second photoelectric conversion section for receiving the light passing through the other area through the microlens. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an imaging element, a focus detection device, and an imaging device.

In order to perform imaging of an image formed by an optical system and focus detection of the optical system, an imaging device in which focus detection pixels are arranged in a part of a two-dimensional array of imaging pixels is known (for example, Patent Documents). 1).
This image sensor is provided with a pair of photoelectric conversion units in one focus detection pixel, and detects a deviation amount of a pair of images formed by a pair of light beams that have passed through a pair of areas of an exit pupil of an optical system. This is used to perform focus detection by a so-called pupil division type phase difference detection system that detects the focus adjustment state of the optical system based on this shift amount.

Prior art documents related to the invention of this application include the following.
JP 2003-244712 A

  However, in the conventional imaging device described above, since two photoelectric conversion units are provided in one focus detection pixel, an output signal different from that of an imaging pixel having one photoelectric conversion unit in one pixel. There is a problem that a readout circuit is required, the signal circuit around the focus detection pixel is complicated, and signal readout control is complicated.

(1) According to the first aspect of the present invention, the focus adjustment state of the optical system is set in place of the imaging pixel in a part of the imaging element in which imaging pixels for imaging an image formed by the optical system are two-dimensionally arranged. An image sensor in which first focus detection pixels and second focus detection pixels for detection are alternately arranged in a straight line, and the first focus detection pixels are a pair of exit pupils of an optical system via a microlens. A first photoelectric conversion unit that receives light that has passed through one of the regions, and the second focus detection pixel includes a second photoelectric conversion unit that receives light that has passed through the other region via the microlens. Prepare.
(2) According to the invention of claim 2, in the imaging device according to claim 1, the same number of first focus detection pixels and second focus detection pixels are arranged.
(3) According to a third aspect of the present invention, in the imaging device according to the first aspect, different numbers of first focus detection pixels and second focus detection pixels are arranged.
(4) According to a fourth aspect of the present invention, in the imaging device according to any one of the first to third aspects, the array of the first focus detection pixels and the second focus detection pixels includes an image pickup pixel.
(5) The invention of claim 5 provides the same number of first focus detections from the image sensor according to any one of claims 1 to 4 and an array of first focus detection pixels and second focus detection pixels. The pixel and the second focus detection pixel are extracted, the signal readout means for reading out the pixel signals of the extracted first focus detection pixel and the second focus detection pixel, the first focus detection pixel and the second read out by the signal readout means The focus detection apparatus includes a focus detection unit that detects a focus adjustment state of the optical system based on a pixel signal of the focus detection pixel.
(6) A sixth aspect of the present invention is the imaging element according to any one of the first to fourth aspects, and a different number of first focus detections from an array of first focus detection pixels and second focus detection pixels. The pixel and the second focus detection pixel are extracted, the signal readout means for reading out the pixel signals of the extracted first focus detection pixel and the second focus detection pixel, the first focus detection pixel and the second read out by the signal readout means Focus detection means for detecting the focus adjustment state of the optical system based on the pixel signal of the focus detection pixel.
(7) The invention of claim 7 is an image pickup device according to any one of claims 1 to 4, and a signal reading unit that reads out a pixel signal from the image pickup pixel, the first focus detection pixel, and the second focus detection pixel. Interpolating means for calculating pixel signals for imaging at the positions of the first focus detection pixel and the second focus detection pixel by interpolation based on pixel signals of imaging pixels around the first focus detection pixel and the second focus detection pixel And an imaging device that generates an image using pixel signals of the imaging pixels and pixel signals for imaging at the positions of the first focus detection pixels and the second focus detection pixels after interpolation by the interpolation unit.

  According to the present invention, the signal readout circuit around the focus detection pixel can be configured in the same manner as the signal readout circuit around the imaging pixel, and the signal readout control from the focus detection pixel is also the signal readout control from the imaging pixel. It can be handled in the same way, and the circuit and control can be configured simply.

  An imaging device according to an embodiment in which two types of focus detection pixels are arranged in a part of a two-dimensional array of imaging pixels, and a focus detection device and an imaging device using the imaging device will be described. As a focus detection apparatus and an imaging apparatus provided with an imaging device according to an embodiment, a lens interchangeable single-lens reflex digital still camera will be described as an example. The imaging device of the present invention is not limited to a single-lens reflex camera still camera, and can be applied to a focus detection device and an imaging device such as a compact camera and a video camera, for example.

  FIG. 1 is a cross-sectional view of a camera showing a configuration of a camera (imaging device) according to an embodiment. A digital still camera 201 according to an embodiment includes an interchangeable lens 202 and a camera body 203, 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.

  The interchangeable lens 202 includes a lens 209, a zooming lens 208, a focusing lens 210, an aperture 211, a lens drive control device 206, and the like. The lens drive control device 206 includes a microcomputer (not shown), a memory, a drive control circuit, and the like. The lens drive control device 206 includes drive control for adjusting the focus of the focusing lens 210 and the aperture diameter of the aperture 211, zooming lens 208, and focusing. In addition to detecting the state of the lens 210 and the aperture 211, the lens information is transmitted and the camera information is received through communication with a body drive 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 camera body 203 includes an imaging element 212, a body drive control device 214, a liquid crystal display element drive circuit 215, a liquid crystal display element 216, an eyepiece lens 217, a memory card 219, and the like. In the imaging element 212, imaging pixels are two-dimensionally arranged, and focus detection pixels are incorporated in portions corresponding to focus detection positions. Details of the image sensor 212 will be described later.

  The body drive control device 214 includes a microcomputer, a memory, a drive control circuit, and the like, and controls the drive of the image sensor 212, reads out the image signal and the focus detection signal, performs the focus detection calculation based on the focus detection signal, and the focus of the interchangeable lens 202. The adjustment is repeated, and image signal processing and recording, camera operation control, and the like are performed. The body drive control device 214 communicates with the lens drive control device 206 via the electrical contact 213 to receive lens information and send camera information (defocus amount, aperture value, etc.).

  The liquid crystal display element 216 functions as an electric view finder (EVF). The liquid crystal display element driving circuit 215 displays a through image by the imaging element 212 on the liquid crystal display element 216, and the photographer can observe the through image through the eyepiece lens 217. The memory card 219 is an image storage that stores an image captured by the image sensor 212.

  A subject image is formed on the light receiving surface of the image sensor 212 by the light beam that has passed through the interchangeable lens 202. This subject image is photoelectrically converted by the image sensor 212, and an image signal and a focus detection signal are sent to the body drive control device 214.

  The body drive control device 214 calculates the defocus amount based on the focus detection signal from the focus detection pixel of the image sensor 212 and sends the defocus amount to the lens drive control device 206. The body drive control device 214 processes the image signal from the image sensor 212 to generate an image, stores the image in the memory card 219, and sends the through image signal from the image sensor 212 to the liquid crystal display element drive circuit 215. The through image is displayed on the liquid crystal display element 216. Further, the body drive control device 214 sends aperture control information to the lens drive control device 206 to control the aperture of the aperture 211.

  The lens drive controller 206 updates the lens information according to the focusing state, zooming state, aperture setting state, aperture opening F value, and the like. Specifically, the positions of the zooming lens 208 and the focusing lens 210 and the aperture value of the aperture 211 are detected, and lens information is calculated according to these lens positions and aperture values, or a lookup prepared in advance. Lens information corresponding to the lens position and aperture value is selected from the table.

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

  FIG. 2 is a diagram showing a focus detection position on the photographing screen of the interchangeable lens 202. A focus detection pixel row on the image sensor 212 described later samples an image on the photographing screen when focus detection, that is, a focus. An example of a detection area and a focus detection position is shown. In this example, focus detection areas 101 to 105 are arranged at the center of the rectangular shooting screen 100 and at five locations on the top, bottom, left and right. In the focus detection areas 101 to 103, focus detection pixels are linearly arranged in the horizontal direction (horizontal direction) of the screen 100, and in the focus detection areas 104 and 105, the focus detection pixels are linear in the vertical direction (vertical direction) of the screen 100. Is arranged.

  Note that the position, number, and direction of the focus detection areas (the direction of the focus detection pixel array) are not limited to those shown in FIG. 2, and may be, for example, an oblique direction or a cross shape in which two focus detection areas intersect. It is good.

  FIG. 3 is a front view showing a detailed configuration of the image sensor 212, and shows the vicinity of the focus detection area 104 on the image sensor 212 in an enlarged manner. The pixel array in the vicinity of the focus detection area 105 is the same as the pixel array in the vicinity of the focus detection area 104 shown in FIG. In FIG. 3, imaging pixels 310 are densely arranged in a two-dimensional square lattice pattern on the imaging element 212, and focus detection pixels 312 for focus detection are provided at positions corresponding to the focus detection area 104 instead of the imaging pixels 310. 313 are alternately arranged adjacent to each other on a straight line in the vertical direction. Further, in the focus detection areas 101 to 103 arranged in the left and right direction of the screen 100 shown in FIG. 2, focus detection pixels 312 and 313 are arranged on a straight line in the left and right direction, and the imaging pixels 310 are arranged around the focus detection pixels 312 and 313. Yes.

  FIG. 4 is a front view of the imaging pixel 310. The imaging pixel 310 includes the microlens 10, the photoelectric conversion unit 11, a color filter (not shown), an output circuit (not shown), and the like. 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 device 212, image pickup pixels 310 having respective color filters are arranged in a Bayer array. The photoelectric conversion unit 11 of the imaging pixel 310 is designed so as to receive all the light beams that pass through the exit pupil diameter (for example, F1.0) of the brightest interchangeable lens by the microlens 10.

  FIG. 6 is a cross-sectional view of the imaging pixel 310. In the imaging pixel 310, the microlens 10 is disposed in front of the photoelectric conversion unit 11 for imaging, and the shape of the photoelectric conversion unit 11 is projected forward by the microlens 10. The photoelectric conversion unit 11 is formed on the semiconductor circuit substrate 29. A color filter (not shown) is arranged between the microlens 10 and the photoelectric conversion unit 11.

  FIG. 7 is a front view when the focus detection pixels 312 and 313 are arranged in the arrangement direction. As shown in FIG. 7A, the focus detection pixel 312 includes the microlens 10 and the photoelectric conversion unit 12, and the photoelectric conversion unit 12 has a rectangular shape. Similarly, the focus detection pixel 313 includes the microlens 10 and the photoelectric conversion unit 13 as illustrated in FIG. 7B, and the photoelectric conversion unit 13 has a rectangular shape.

  In the focus detection areas 104 and 105 in the vertical direction of the screen 100 shown in FIG. 2, when the focus detection pixels 312 and the focus detection pixels 313 are displayed with the microlens 10 superimposed, the photoelectric conversion units 12 and 13 are displayed on the top and bottom of the screen 100. It is lined up in the direction. The focus detection pixels 312 and the focus detection pixels 313 are alternately arranged in the vertical direction of the screen in the focus detection areas 104 and 105, that is, in the arrangement direction of the photoelectric conversion units 12 and 13. On the other hand, in the focus detection areas 101 to 103 in the horizontal direction of the shooting screen 100, when the focus detection pixels 312 and the focus detection pixels 313 are displayed with the microlens 10 superimposed, the photoelectric conversion units 12 and 13 are arranged in the horizontal direction. It is out. The focus detection pixels 312 and the focus detection pixels 313 are alternately arranged in the horizontal direction of the screen, that is, in the alignment direction of the photoelectric conversion units 12 and 13 in the focus detection areas 101 to 103.

  The photoelectric conversion units 12 and 13 of the focus detection pixels 312 and 313 are designed so as to receive all the light beams that pass through a predetermined region (for example, F2.8) of the exit pupil of the interchangeable lens by the microlens 10. The focus detection pixels 312 and 313 are not provided with a color filter in order to increase the amount of light, and the spectral characteristics of the focus detection pixels 312 and 313 include the spectral sensitivity of a photodiode that performs photoelectric conversion and the spectral characteristics of an infrared cut filter (not shown). Spectral characteristics (see FIG. 5). 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. 8, 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.

  Focus detection pixels 312 and 313 for focus detection are arranged in a column in which the blue pixel and the green pixel of the imaging pixel 310 are to be arranged. The focus detection pixels 312 and 313 for focus detection are arranged in a column in which the blue pixel and the green pixel of the imaging pixel 310 should be arranged because human visual characteristics when an interpolation error occurs in the pixel interpolation process. This is because the blue pixel interpolation error is less conspicuous than the red pixel interpolation error.

  FIG. 9A is a cross-sectional view of the focus detection pixel 312. In the focus detection pixel 312 disposed in the focus detection area 101 at the center of the screen, the microlens 10 is disposed in front of the photoelectric conversion unit 12, and the shape of the photoelectric conversion unit 12 is projected forward by the microlens 10. The photoelectric conversion unit 12 is formed on the semiconductor circuit substrate 29, and the microlens 10 is integrally and fixedly formed thereon by a semiconductor image sensor manufacturing process. Note that the focus detection pixels 312 disposed in the other focus detection areas 102 to 105 also have the same cross-sectional structure.

  FIG. 9B is a cross-sectional view of the focus detection pixel 313. In the focus detection pixel 313 disposed in the focus detection area 101 at the center of the screen, the microlens 10 is disposed in front of the photoelectric conversion unit 13, and the shape of the photoelectric conversion unit 13 is projected forward by the microlens 10. The photoelectric conversion unit 13 is formed on the semiconductor circuit substrate 29, and the microlens 10 is integrally and fixedly formed thereon by a semiconductor image sensor manufacturing process. Note that the focus detection pixels 313 arranged in the other focus detection areas 102 to 105 also have the same cross-sectional structure.

  FIG. 10 is a diagram showing a configuration of a focus detection optical system of a pupil division type phase difference detection method using a microlens at the center of the photographing screen. Reference numeral 90 denotes a pupil plane (hereinafter referred to as a distance measuring pupil plane) set at a distance d in front of the microlens arranged on the planned imaging plane of the interchangeable lens, and the distance d is the curvature, refractive index, This distance is determined according to the distance between the microlens and the photoelectric conversion unit (hereinafter referred to as distance measuring pupil distance). 91 is an optical axis of the interchangeable lens, 10a to 10d are microlenses, 12a, 12b, 13a and 13b are photoelectric conversion units, 312a, 312b, 313a and 313b are focus detection pixels, and 72, 73, 82 and 83 are for focus detection. Luminous flux. Reference numeral 92 denotes an area of the photoelectric conversion units 12a and 12b projected by the microlenses 10a and 10c, and is hereinafter referred to as a distance measuring pupil. Reference numeral 93 denotes an area of the photoelectric conversion units 13a and 13b projected by the microlenses 10b and 10d, and is hereinafter referred to as a distance measuring pupil.

  In FIG. 10, four focus detection pixels (pixels 312a, 313a, 312b, and 313b) adjacent to the photographing optical axis 91 are schematically illustrated. However, in other focus detection pixels, the photoelectric conversion units are respectively Light beams coming from the corresponding distance measurement pupils 92 and 93 to each microlens are received. The arrangement direction of the focus detection pixels coincides with the arrangement direction of the pair of distance measuring pupils, that is, the arrangement direction of the pair of photoelectric conversion units.

  The microlenses 10a to 10d are arranged in the vicinity of the planned imaging plane of the interchangeable lens, and the shapes of the photoelectric conversion units 12a, 13a, 12b, and 13b arranged behind the microlenses 10a to 10d are the microlenses 10a to 10d. Is projected onto the distance measuring pupil plane 90 separated from the distance measuring pupil distance d by the distance measurement pupil distance d, and the projection shape forms distance measuring pupils 92 and 93. That is, the microlens and the photoelectric conversion unit in each focus detection pixel so that the projection shapes (distance detection pupils 92 and 93) of the photoelectric conversion unit of each focus detection pixel match on the distance measurement pupil plane 90 at the projection distance d. Is determined, and the projection direction of the photoelectric conversion unit in each focus detection pixel is thereby determined.

  The photoelectric conversion unit 12a outputs a signal corresponding to the intensity of the image formed on the microlens 10a by the light beam 72 that passes through the distance measuring pupil 92 and travels toward the microlens 10a. The photoelectric conversion unit 12b outputs a signal corresponding to the intensity of the image formed on the microlens 10c by the light beam 82 passing through the distance measuring pupil 92 and traveling toward the microlens 10c. In addition, the photoelectric conversion unit 13a outputs a signal corresponding to the intensity of the image formed on the microlens 10b by the light flux 73 that passes through the distance measuring pupil 93 and travels toward the microlens 10b. The photoelectric conversion unit 13b outputs a signal corresponding to the intensity of the image formed on the microlens 10d by the light beam 83 passing through the distance measuring pupil 93 and traveling toward the microlens 10d.

  A large number of the two types of focus detection pixels as described above are arranged on a straight line, and the output of the photoelectric conversion unit of each pixel is grouped into an output group corresponding to the distance measurement pupil 92 and the distance measurement pupil 93, whereby the distance measurement pupil 92 is obtained. And information on the intensity distribution of a pair of images formed on the pixel array by the focus detection light beams that pass through the distance measuring pupil 93, respectively. By performing a known image shift detection calculation process (correlation calculation process, phase difference detection process) on this information, the image shift amount of a pair of images is detected by a so-called pupil division type phase difference detection method. By converting the image shift amount according to the center of gravity of the pair of distance measuring pupils, the current image plane relative to the planned image plane (the focus detection position corresponding to the position of the microlens array on the planned image plane) The deviation (defocus amount) of the imaging plane) is calculated.

  In the imaging device 212 in which two types of focus detection pixels 312 and 313 are arranged in a part of a two-dimensional array of the imaging pixels 310, these two types of focus detection pixels 312 and 313 are the same as one focus detection pixel 312 and 313. A pair of photoelectric conversion units 12 or 13 is provided therein, and a pair of photoelectric conversion units 12 and 13 receive a pair of images formed by a pair of light beams that have passed through a pair of regions of the pupil of the interchangeable lens 202. A pair of signals corresponding to the pair of images is output. Therefore, the two types of focus detection pixels 312 and 313 can be said to be a pair of focus detection pixels. A so-called pupil division type phase difference detection system that detects a shift amount of a pair of images based on output signals of the pair of focus detection pixels 312 and 313 and detects a focus adjustment state of the interchangeable lens 202 based on the shift amount. Focus detection is performed.

  There are two possible methods for arranging the focus detection pixels 312 and 313 as follows. The first arrangement method is a method of alternately arranging the same number of focus detection pixels 312 and 313 as shown in FIG. 11 (a), and the second arrangement method is a method of focusing as shown in FIG. 11 (b). In this method, only one of the detection pixels 312 and 313 is used in an extra manner, and they are alternately arranged. In the example shown in FIG. 11B, the number of focus detection pixels 312 is one more than the number of focus detection 313 arrays. In FIG. 11, for easy understanding, the image sensor is shown as an image sensor having 8 pixels horizontally and 5 pixels vertically.

  According to the former arrangement method in which the same number of pairs of focus detection pixels 312 and 313 are used and arranged alternately with each other, there is no remainder of the pixels, so when reading, particularly when the imaging pixels 310 are arranged in a Bayer array. Processing of output signals from the pixel 310 and the focus detection pixels 312 and 313 is facilitated, and the focus detection time can be shortened. In addition, there is an advantage that it is easy to cope with thinning-out readout when a captured image is displayed in a viewfinder.

  On the other hand, according to the latter arrangement method in which only one of the pair of focus detection pixels 312 and 313 is used and arranged alternately, the center position of the array of one focus detection pixel 312 and the other There is an advantage that the center position of the array of the focus detection pixels 313 coincides and the focus detection accuracy is improved.

  Note that the same number of pairs of focus detection pixels 312 and 313 are used, and either one of the pair of focus detection pixels 312 and 313 is used more frequently from the long focus detection pixel array alternately arranged with each other. The signals of the same number of focus detection pixels 312 and 313 are read out from the long focus detection pixel array alternately arranged with each other, or the signals of different numbers of focus detection pixels 312 and 313 are read out according to the shooting conditions. You may make it switch whether it reads.

  For example, when high-speed response for focus detection is required, such as when a moving subject is captured and focus detection is performed, the same number of focus detection pixels 312 and 313 are read out to perform focus detection. When high-precision focus detection is required, for example, when a subject with low contrast is captured and focus detection is performed, only one of the focus detection pixels 312 and 313 is read out to detect the focus. Do.

  In the above-described focus detection pixel array, an example in which a pair of focus detection pixels 312 and 313 are alternately arranged without a gap is shown, but the imaging pixels 310 may be sandwiched between the focus detection pixels 312 and 313. .

  FIG. 12 shows a modified focus detection pixel array. In FIG. 12, only the focus detection pixel array portion is shown enlarged. FIG. 12A shows an example of a focus detection pixel array in which adjacent focus detection pixels 312 and 313 are paired and an imaging pixel 310 is sandwiched between a pair and an adjacent pair. Since the focus detection pixels 312, 313 form a pair, the same number is used. FIG. 12B shows an example in which the same number of the pair of focus detection pixel rows 312 and 313 are used, and these are alternately arranged with the imaging pixels 310 interposed therebetween. Further, FIG. 12C shows an example in which only one focus detection pixel 312 is used in many of the pair of focus detection pixels 312, 313, and these are alternately arranged with the imaging pixel 310 interposed therebetween. .

  As described above, by arranging the imaging pixel 310 between the focus detection pixels 312 and 313 and interpolating the imaging signals at the positions of the focus detection pixels 312 and 313 based on the outputs of the surrounding imaging pixels 310. In addition, the imaging pixel 310 sandwiched between the focus detection pixel rows can be used for the interpolation calculation, and the imaging signal at the focus detection pixel position can be accurately estimated. Therefore, an image closer to an actual subject can be generated.

  In addition to the arrangement shown in FIG. 12, any arrangement may be used as long as the imaging pixels 310 are included in the arrangement of the focus detection pixels 312 and 313, but the arrangement of the focus detection pixels 312 and 313 is not limited. As the number of imaging pixels 310 included in the array increases, the focus detection pixel pitch increases and the resolution in focus detection decreases. Therefore, it is necessary to balance the image generated by interpolation and the focus detection resolution.

  In the focus detection pixels 312 and 313 described above, an example using rectangular photoelectric conversion units 12 and 13 as shown in FIGS. 7A and 7B is shown, but FIGS. 13A and 13B show examples. Focus detection pixels 314 and 315 having semicircular photoelectric conversion units 16 and 17 as shown may be used. FIG. 14 is a partially enlarged view of an image pickup element 212A of a modified example configured using such focus detection pixels 314 and 315. If the photoelectric conversion unit of the focus detection pixel is semicircular, more light flux that has passed through the exit pupil of the optical system can be received compared to the rectangular photoelectric conversion unit, thus improving the focus detection performance when the subject is dark. be able to.

  The shape of the photoelectric conversion unit of the focus detection pixel can be various shapes in addition to the above-described rectangle or semicircle.

  In the image pickup device described above, an example in which the color filters of the image pickup pixels 310 are arranged in a Bayer array is shown, but a complementary color array may be used.

  As described above, according to the embodiment, the interchangeable lens is used instead of the image pickup pixel 310 in a part of the image pickup element in which the image pickup pixels 310 for picking up the image formed by the interchangeable lens 202 are two-dimensionally arranged. 202 is an imaging device in which first focus detection pixels 312 and 314 and second focus detection pixels 313 and 315 for detecting a focus adjustment state 202 are alternately arranged in a straight line, and the first focus detection pixels. 312 and 314 include first photoelectric conversion units 12 and 16 that receive light that has passed through one of the pair of regions of the exit pupil of the optical system via the microlens, and the second focus detection pixel. Since 313 and 315 include the second photoelectric conversion units 13 and 17 that receive light that has passed through the other region via the microlens, the signal readout circuit around the focus detection pixel is used as the signal around the imaging pixel. Reading On which can be configured similarly to the out circuit, the signal read-out control from the focus detection pixels also can be treated like signal reading control from the imaging pixels can be briefly form a circuit and control.

The figure which shows the structure of the imaging device of one embodiment The figure which shows the focus detection position on the photographing screen of the interchangeable lens Front view showing detailed configuration of image sensor Front view of imaging pixels Diagram showing spectral sensitivity characteristics of imaging pixels Cross section of imaging pixel Front view of focus detection pixels The figure which shows the spectral sensitivity characteristic of a focus detection pixel Cross section of focus detection pixel The figure which shows the structure of the focus detection optical system of the pupil division type phase difference detection method using the micro lens in the photographing screen center The figure which shows the arrangement | sequence method of a focus detection pixel The figure which shows the focus detection pixel arrangement | sequence of a modification. The figure which shows the focus detection pixel of a modification. The figure which shows the image pick-up element of the modification which arranged the focus detection pixel shown in FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10; Micro lens, 11, 12, 13, 16, 17; Photoelectric conversion part, 201; Imaging device (camera), 202; Interchangeable lens, 212, 212A; Imaging element, 214; Body drive control device, 310; , 312, 313, 314, 315; focus detection pixels

Claims (7)

First focus detection for detecting a focus adjustment state of the optical system instead of the imaging pixel in a part of an imaging element in which imaging pixels for imaging an image formed by the optical system are two-dimensionally arranged An imaging device in which pixels and second focus detection pixels are alternately arranged in a straight line,
The first focus detection pixel includes a first photoelectric conversion unit that receives light that has passed through one region of a pair of regions of the exit pupil of the optical system via a microlens,
The second focus detection pixel includes a second photoelectric conversion unit that receives light that has passed through the other region via a microlens. The imaging device according to claim 1,
An imaging device, wherein the same number of the first focus detection pixels and the second focus detection pixels are arranged. The imaging device according to claim 1,
An imaging device, wherein a different number of the first focus detection pixels and the second focus detection pixels are arranged. The imaging device according to any one of claims 1 to 3,
The imaging device, wherein the imaging pixels are included in an array of the first focus detection pixels and the second focus detection pixels. The imaging device according to any one of claims 1 to 4,
The same number of the first focus detection pixels and the second focus detection pixels are extracted from the array of the first focus detection pixels and the second focus detection pixels, and the extracted first focus detection pixels and the second focus detection pixels are extracted. Signal readout means for reading out the pixel signal of the focus detection pixel;
Focusing means comprising focus detection means for detecting a focus adjustment state of the optical system based on pixel signals of the first focus detection pixels and the second focus detection pixels read by the signal reading means. Detection device. The imaging device according to any one of claims 1 to 4,
Different numbers of the first focus detection pixels and the second focus detection pixels are extracted from the array of the first focus detection pixels and the second focus detection pixels, and the extracted first focus detection pixels and the second focus detection pixels are extracted. Signal readout means for reading out the pixel signal of the focus detection pixel;
Focusing means comprising focus detection means for detecting a focus adjustment state of the optical system based on pixel signals of the first focus detection pixels and the second focus detection pixels read by the signal reading means. Detection device. The imaging device according to any one of claims 1 to 4,
Signal readout means for reading out pixel signals from the imaging pixel, the first focus detection pixel, and the second focus detection pixel;
The pixel signals for imaging at the positions of the first focus detection pixel and the second focus detection pixel are interpolated based on pixel signals of the imaging pixels around the first focus detection pixel and the second focus detection pixel. Interpolating means for calculating,
An image pickup apparatus, wherein an image is generated by the pixel signal of the image pickup pixel and the pixel signal for image pickup at the position of the first focus detection pixel and the second focus detection pixel after interpolation by the interpolation means.

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