JP4957413B2 - Solid-state imaging device and imaging apparatus using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To increase an amount of incident light on pixels for detecting a focal point to ensure an effect of enhancing the accuracy of detecting the focal point to some extent while reducing a difference between an imaging signal obtained from an imaging pixel in the vicinity of the pixels for detecting the focal point and the imaging signal obtained from the imaging pixel in a region except the vicinity of the pixel for detecting the focal point, to obtain an image of high quality. <P>SOLUTION: A plurality of pixels disposed two-dimensionally contain: a plurality of imaging pixels 20A for outputting the imaging signal for forming an image signal indicating a subject image; and a plurality of pixels for detecting a focal point 20R, 20L, 20U and 20D for outputting a focal point detecting signal for detecting a focal point adjusting state. In the imaging pixels 20A, a color filter of red (R), green (G) or blue (B) is provided. Meanwhile, in the pixels for detecting the focal point 20R, 20L, 20U and, 20D, a color filter of a cyanogenic color (Cy) is provided. <P>COPYRIGHT: (C)2009,JPO&amp;INPIT

Description

  The present invention relates to a solid-state imaging device and an imaging apparatus using the same.

  In recent years, imaging devices such as video cameras and electronic cameras have been widely spread. These cameras use a solid-state imaging device such as a CCD type or an amplification type. In these solid-state imaging devices, a plurality of pixels having a photoelectric conversion unit that generates a signal charge according to the amount of incident light are arranged in a matrix.

  In the amplification type solid-state imaging device, signal charges generated and stored in the photoelectric conversion unit of the pixel are guided to an amplification unit provided in the pixel, and a signal amplified by the amplification unit is output from the pixel. As the amplification type solid-state imaging device, for example, a solid-state imaging device using a junction field effect transistor in the amplification unit (Patent Documents 1 and 2), or a CMOS type solid-state imaging device using a MOS transistor in the amplification unit (Patent Document 3) has been proposed.

  By the way, in order to realize automatic focus adjustment in an electronic camera, it is necessary to detect the focus adjustment state of the imaging lens. Conventionally, a focus detection element is provided separately from a solid-state image sensor used for imaging. However, in that case, the cost increases by the focus detection element and the focus detection optical system that guides light to the focus detection element, and the size of the device increases accordingly.

  Therefore, in recent years, a solid-state imaging device has been proposed which is configured to adopt a so-called pupil division phase difference method as a focus detection method and also to be used as a focus detection device (for example, Patent Document 4).

  In the solid-state imaging device disclosed in Patent Document 4, a focus detection signal (“AF signal”) indicating a focus adjustment state is provided separately from the imaging pixels that output an imaging signal for forming an image signal indicating a subject image. A plurality of focus detection pixels (also referred to as “AF pixels”) are generated. In this solid-state imaging device, the AF pixel has a photoelectric conversion unit divided into two. On such a photoelectric conversion unit, microlenses are provided on a one-to-one basis with respect to pixels. The two-divided photoelectric conversion unit is arranged at a position where the microlens is in a substantially imaging relationship (that is, substantially conjugate) with the exit pupil of the imaging lens. Therefore, since the distance between the exit pupil of the imaging lens and the microlens is sufficiently long with respect to the size of the microlens, the two-divided photoelectric conversion unit is disposed at a substantially focal position of the microlens. It will be. From the relationship described above, in each pixel, one part of the photoelectric conversion unit divided into two parts is a part of the exit pupil of the imaging lens and emits a light beam from an area decentered in a predetermined direction from the center of the exit pupil. The light is selectively received and photoelectrically converted. In each AF pixel, the other part of the photoelectric conversion unit divided into two parts selectively receives a light beam from a region that is part of the exit pupil of the imaging lens and decentered in the opposite direction from the center of the exit pupil. And photoelectric conversion.

  In general, such AF pixels are not arranged uniformly in the effective pixel region of the solid-state imaging device, but are partially arranged vertically, horizontally, or partially in the center. The reason for this arrangement is to generate AF signals efficiently and increase the number of imaging pixels as much as possible.

In the solid-state imaging device disclosed in Patent Document 4, a color filter is provided in the imaging pixel, but no color filter is provided in the AF pixel (paragraphs [0063] and [0064 of Patent Document 4]. ]).
JP-A-11-177076 JP 2004-335882 A JP 2004-111590 A JP 2000-292686 A

  However, when an image is actually picked up using a solid-state imaging device as disclosed in Patent Document 4, a region where the luminance increases compared to the other is generated even though a subject having a uniform luminance is picked up. It was. Further analysis shows that the region is a region near the region where the AF pixels are arranged.

  That is, even if the same light is incident on the imaging pixels near the AF pixels and the imaging pixels in the region other than the AF pixels, there is a difference in the magnitude of the imaging signal obtained between them. It was. As a result, a high-brightness region is clearly formed in a line along the AF pixel array, resulting in poor quality images.

  The present invention has been made in view of such problems, and is intended for imaging in the vicinity of a focus detection pixel while ensuring to some extent the effect of increasing the amount of incident light to the focus detection pixel and improving the accuracy of focus detection. The difference between the imaging signal obtained from the pixel and the imaging signal obtained from the imaging pixel in a region other than the vicinity of the focus detection pixel can be reduced, and thus a high-quality image can be obtained. An object of the present invention is to provide a solid-state imaging device and an imaging apparatus using the same.

  As a result of intensive studies, the present inventors have found the cause of the above problems. In the conventional solid-state imaging device described above, as described above, the color filter is removed from the AF pixel. As a result, in the AF pixel, light from a short wavelength, which is a blue component, to a long wavelength light, which is a red component, is incident, so that the amount of light incident on the AF pixel is increased, and thus the accuracy of focus detection is improved. There is an excellent effect.

  However, in the AF pixel, a light component having a long wavelength such as red is incident. Such light enters the semiconductor deeper than the incident surface and is photoelectrically converted. The electric charges generated in the deep position of the semiconductor substrate move in all directions due to drift. If the drifted charge is trapped in the charge storage layer disposed in the AF pixel, no particular problem occurs. However, as the position where charge is generated is deeper, the component that is not captured by the AF pixel and is captured by the charge storage layer of the adjacent imaging pixel increases. The above problem was caused by this phenomenon.

  Although it is so-called crosstalk, it is different from generally called crosstalk. That is, this phenomenon is caused by charges mixed from the AF pixel to the imaging pixel in the vicinity thereof. The AF pixel is arranged in a specific area of the effective pixel area. Therefore, a clear and high-bright area is observed along the area where the AF pixels are arranged in the effective pixel area.

  The present invention has been made as a result of investigating the cause of such problems. That is, in order to solve the above-described problem, the solid-state imaging device according to the first aspect of the present invention is a solid-state imaging device that photoelectrically converts a subject image formed by an optical system, and is arranged in a two-dimensional manner. A plurality of pixels having a photoelectric conversion unit that generates and accumulates charges according to incident light, and the plurality of pixels outputs a plurality of imaging signals for forming an image signal indicating the subject image; A plurality of focus detection pixels that output a focus detection signal for detecting a focus adjustment state of the optical system, and the imaging pixels are divided into first to third groups, The imaging pixels in the first group are provided with a red color filter, the imaging pixels in the second group are provided with a green color filter, and the imaging pixels in the third group are blue. Karafu The focus detection pixel is provided with an optical filter having a light transmission characteristic different from any of the red color filter, the green color filter, and the blue color filter, and in a wavelength range of 420 nm to 500 nm. The transmittance of the optical filter is 30% or more, and the transmittance of the optical filter in the wavelength range of 590 nm to 650 nm is 30% or less.

  In the first aspect, the transmittance of the optical filter in a wavelength region of 410 nm to 510 nm is more preferably 30% or more, and the transmittance of the optical filter in a wavelength region of 400 nm to 520 nm is 30% or more. Is more preferable. In the first aspect, the transmittance of the optical filter in the wavelength region of 570 nm to 650 nm is more preferably 30% or less, and the transmittance of the optical filter in the wavelength region of 550 nm to 650 nm is 30%. % Or less is even more preferable.

  The solid-state imaging device according to the second aspect of the present invention is a solid-state imaging device that photoelectrically converts a subject image formed by an optical system, and is arranged in a two-dimensional manner, and each generates a charge corresponding to incident light. A plurality of pixels each having a photoelectric conversion unit that accumulates, the plurality of pixels including a plurality of imaging pixels that output an imaging signal for forming an image signal indicating the subject image; and focus adjustment of the optical system A plurality of focus detection pixels that output a focus detection signal for detecting a state, and the imaging pixels are divided into first to third groups, and the imaging pixels of the first group Is provided with a red color filter, the second group of imaging pixels is provided with a green color filter, and the third group of imaging pixels is provided with a blue color filter, and the focus detection Drawing Is provided with an optical filter having a light transmission characteristic different from any of the red color filter, the green color filter, and the blue color filter, and relates to a wavelength of transmittance of the optical filter in a wavelength range of 400 nm to 600 nm. The integral value is larger than both the integral value of the green color filter and the integral value of the blue color filter, and the integral value of the optical filter in the wavelength region of 600 nm to 700 nm is It is smaller than the integral value of the red color filter.

  In the solid-state imaging device according to the third aspect of the present invention, in the second aspect, the transmittance of the optical filter in a wavelength region of 600 nm or more and 650 nm or less is 20% or less.

  In the solid-state imaging device according to the fourth aspect of the present invention, in the second or third aspect, the transmittance of the optical filter in a wavelength region of 410 nm or more and 550 nm or less is 40% or more.

  In the solid-state imaging device according to the fifth aspect of the present invention, in any one of the first to fourth aspects, the optical filter is a cyan color filter.

  A solid-state imaging device according to a sixth aspect of the present invention is a solid-state imaging device that photoelectrically converts a subject image formed by an optical system, and is arranged in a two-dimensional manner, and each generates a charge corresponding to incident light. A plurality of pixels each having a photoelectric conversion unit that accumulates, the plurality of pixels including a plurality of imaging pixels that output an imaging signal for forming an image signal indicating the subject image; and focus adjustment of the optical system A plurality of focus detection pixels that output a focus detection signal for detecting a state, and the imaging pixels are divided into first to third groups, and the imaging pixels of the first group Is provided with a red color filter, the second group of imaging pixels is provided with a green color filter, and the third group of imaging pixels is provided with a blue color filter, and the focus detection Drawing The one in which the color filters of cyan color is provided.

  According to a seventh aspect of the present invention, there is provided an imaging apparatus that uses the solid-state imaging device according to any one of the first to sixth aspects and the focus detection signal from at least some of the plurality of focus detection pixels. A detection processing unit that outputs a detection signal indicating a focus adjustment state of the optical system, and an adjustment unit that performs focus adjustment of the optical system based on the detection signal from the detection processing unit. It is.

  According to the present invention, an imaging signal obtained from imaging pixels in the vicinity of the focus detection pixel and the focus detection can be ensured to some extent while increasing the amount of incident light to the focus detection pixel to improve the accuracy of focus detection. A solid-state imaging device capable of reducing a difference between imaging signals obtained from imaging pixels in a region other than the vicinity of the imaging pixels, and thus obtaining a high-quality image, and imaging using the same An apparatus can be provided.

  Hereinafter, a solid-state imaging device and an imaging device using the same according to the present invention will be described with reference to the drawings.

  [First Embodiment]

  FIG. 1 is a schematic block diagram showing an electronic camera 1 as an imaging apparatus according to the first embodiment of the present invention. The electronic camera 1 is equipped with a photographing lens 2 as an optical system for forming a subject image. The photographing lens 2 is driven by a lens control unit 2a for focus and diaphragm. In the image space of the photographic lens 2, an imaging surface of a solid-state imaging device 3 that photoelectrically converts a subject image formed by the photographic lens 2 is disposed.

  The solid-state imaging device 3 is driven by a command from the imaging control unit 4 and outputs a signal. The signal output from the solid-state imaging device 3 is either an imaging signal for forming an image signal indicating a subject image or a focus detection signal for detecting the focus adjustment state of the photographing lens 2. In any case, the signal is processed through the signal processing unit 5 and the A / D conversion unit 6 and then temporarily stored in the memory 7. The memory 7 is connected to the bus 8. The bus 8 is also connected with a lens control unit 2a, an imaging control unit 4, a microprocessor 9, a focus calculation unit (detection processing unit) 10, a recording unit 11, an image compression unit 12, an image processing unit 13, and the like. The microprocessor 9 is connected to an operation unit 9a such as a release button. A recording medium 11a is detachably attached to the recording unit 11 described above.

  FIG. 2 is a circuit diagram showing a schematic configuration of the solid-state imaging device 3 in FIG. The solid-state imaging device 3 includes a plurality of pixels 20 arranged in a matrix and a peripheral circuit for outputting a signal from the pixels 20. An effective pixel area (imaging area) in which the pixels 20 are arranged in a matrix is indicated by reference numeral 31. In FIG. 2, the number of pixels indicates 16 pixels of 4 rows horizontally and 4 rows vertically. However, in the present embodiment, the number of pixels is much larger than that. However, in the present invention, the number of pixels is not particularly limited.

  In the present embodiment, the solid-state imaging device 3 includes imaging pixels 20A, which will be described later, as pixels, and focus detection pixels (hereinafter referred to as “AF pixels”) 20R, 20L, and 20U that generate focus detection signals. , 20D, but in FIG. 2, it is indicated by reference numeral 20 without distinguishing between them. The specific circuit configuration and structure will be described later. These pixels 20 output imaging signals or focus detection signals in accordance with peripheral circuit drive signals. In addition, all the pixels 20 can be reset so that the photoelectric conversion unit is simultaneously reset to have the same exposure time and timing, or can be a so-called rolling shutter that reads out one row at a time.

  The peripheral circuit includes a vertical scanning circuit 21, a horizontal scanning circuit 22, driving signal lines 23 and 24 connected thereto, a vertical signal line 25 for receiving a signal from the pixel 20, and a constant current source connected to the vertical signal line 25. 26, a correlated double sampling circuit (CDS circuit) 27, a horizontal signal line 28 for receiving a signal output from the CDS circuit 27, an output amplifier 29, and the like.

  The vertical scanning circuit 21 and the horizontal scanning circuit 22 output drive signals based on a command from the imaging control unit 4 of the electronic camera 1. Each pixel 20 is driven by receiving a drive signal output from the vertical scanning circuit 21 from a predetermined drive signal line 23, and outputs an imaging signal or a focus detection signal to the vertical signal line 25. There are a plurality of drive signals output from the vertical scanning circuit 21, and accordingly, a plurality of drive wirings 23.

  The signal output from the pixel 20 is subjected to predetermined noise removal by the CDS circuit 27. Then, a signal is output to the outside through the horizontal signal line 28 and the output amplifier 29 by the drive signal of the horizontal scanning circuit 22.

  FIG. 3 is a schematic plan view schematically showing the solid-state imaging device 3 (particularly, its effective pixel region 31) in FIG. In the present embodiment, as shown in FIG. 3, the effective pixel region 31 of the solid-state imaging device 3 includes two focus detection regions 32 and 33 having a cross shape disposed in the center, and 2 disposed left and right. Two focus detection areas 34 and 35 and two focus detection areas 36 and 37 arranged above and below are provided. As shown in FIG. 3, an X axis, a Y axis, and a Z axis that are orthogonal to each other are defined. The direction of the arrow in the X-axis direction is called the + X direction or + X side, and the opposite direction is called the -X direction or -X side, and the same applies to the Y-axis direction. A plane parallel to the XY plane coincides with the imaging surface (light receiving surface) of the solid-state imaging device 3. The arrangement in the X-axis direction is a row, and the arrangement in the Y-axis direction is a column. Incident light is incident from the front side of the drawing in FIG. These points are the same for the drawings described later.

  FIG. 4 is a schematic enlarged view in which the vicinity of the intersection of the focus detection areas 32 and 33 in FIG. 3 is enlarged, and schematically shows the pixel arrangement. In the present embodiment, each pixel 20 is provided with a color filter. However, if the colors of the color filter provided in the pixel are classified without distinction, the solid-state imaging device 3 has one type of imaging pixel. 20A and four types of AF pixels 20R, 20L, 20U, and 20D. In the following description, when the type of AF pixel is not distinguished, the AF pixel may be denoted by reference numeral 20F.

  FIG. 5A is a schematic plan view schematically showing the main part of the imaging pixel 20A, and FIG. 5B is a schematic cross-sectional view taken along line X1-X2 in FIG. 5A. The imaging pixel 20A includes a photodiode 41 as a photoelectric conversion unit, a microlens 42 formed on-chip on the photodiode 41, and a red (R) color filter 50R provided on the light incident side of the photodiode 41. , A green (G) color filter 50G or a blue (B) color filter 50B. In FIG. 4, the color of the color filter provided in each imaging pixel 20A is shown as R, G, B. Further, as shown in FIG. 5, a light shielding layer 43 such as a metal layer as a light shielding portion is formed on a substantially focal plane of the microlens 42. The light shielding layer 43 also serves as a wiring layer as necessary. In the light shielding layer 43, a square opening 43a concentric with the optical axis O of the microlens 42 of the imaging pixel 20A is formed in the imaging pixel 20A. The photodiode 41 of the pixel 20A has a size capable of effectively receiving all the light that has passed through the opening 43a. An interlayer insulating film or the like is formed between the light shielding layer 43 and the microlens 42 or between the substrate 44 and the light shielding layer 43.

  In the present embodiment, in the pixel 20 </ b> A, the opening 43 a is formed in the light shielding layer 43 that is disposed substantially at the focal plane of the microlens 42, so that the photodiode 41 of the pixel 20 </ b> A has the exit pupil of the photographing lens 2. Light from a region of the exit pupil (corresponding to a projection image by the microlens 42 of the opening 43a) that is not substantially decentered from the center of the light is received and photoelectrically converted.

  FIG. 6A is a schematic plan view schematically showing the main part of the AF pixel 20R, and FIG. 6B is a schematic cross-sectional view taken along line X3-X4 in FIG. 6A. 6, elements that are the same as or correspond to those in FIG. 5 are given the same reference numerals, and redundant descriptions thereof are omitted. This also applies to FIGS. 7 to 9 described later.

  The AF pixel 20R is different from the imaging pixel 20A in that in the AF pixel 20R, the light shielding layer 43 has a square concentric with the optical axis O of the microlens 42 of the AF pixel 20R (same as the opening 43a). In place of the rectangular opening 43b that is exactly half the size of the right side (+ X side) of the square of the size), and instead of the R, G, B color filters 50R, 50G, 50B, cyan (Cy ) Color filter 50Cy is provided only. In FIG. 4, the color of the color filter provided in each AF pixel 20R (and each AF pixel 20L, 20U, 20D) is shown as Cy. Note that the photodiode 41 of the pixel 20R has the same size as the photodiode 41 of the pixel 20A. As described above, in this embodiment, the opening 43b is half of the opening 43a. However, the present invention is not limited to this. For example, the opening 43b is a square concentric with the optical axis O of the microlens 42 of the AF pixel 20R. A rectangular opening having a size of about 40% or 60% on the right side (+ X side) of (a square having the same size as the opening 43a) may be used. The opening 43b of the AF pixel 20R preferably has the same size as an opening 43c described later of the AF pixel 20L, and an opening 43d described later of the AF pixel 20U is the same as an opening 43e described later of the AF pixel 20D. It is preferable to have a size.

  In the pixel 20R, the opening 43b is formed in the light shielding layer 43, so that the photodiode 41 of the pixel 20R is substantially decentered in the −X direction from the center of the exit pupil of the photographing lens 2. The light flux from the light is selectively received and photoelectrically converted.

  FIG. 7A is a schematic plan view schematically showing the main part of the AF pixel 20L, and FIG. 7B is a schematic cross-sectional view taken along line X5-X6 in FIG. 7A. The AF pixel 20L is different from the imaging pixel 20A in that the AF pixel 20L has a square concentric with the optical axis O of the microlens 42 of the AF pixel 20L (same as the opening 43a). A rectangular opening 43c that is exactly half the size of the left side (-X side) of the square of the size) is formed, and instead of the R, G, B color filters 50R, 50G, 50B, cyan ( The only difference is that the Cy) color filter 50Cy is provided. In the pixel 20L, the opening 43c is formed in the light shielding layer 43, so that the photodiode 41 of the pixel 20L is from the region of the exit pupil substantially decentered in the + X direction from the center of the exit pupil of the photographing lens 2. Are selectively received and photoelectrically converted.

  FIG. 8A is a schematic plan view schematically showing the main part of the AF pixel 20U, and FIG. 8B is a schematic cross-sectional view taken along line Y1-Y2 in FIG. 8A. The AF pixel 20U differs from the imaging pixel 20A in that in the AF pixel 20U, the light shielding layer 43 has a square concentric with the optical axis O of the microlens 42 of the AF pixel 20U (same as the opening 43a). A rectangular opening 43d that is exactly half the size of the upper square (+ Y side) of the square (size) is formed, and instead of the R, G, B color filters 50R, 50G, 50B, cyan (Cy ) Color filter 50Cy is provided only. In the pixel 20U, the opening 43d is formed in the light shielding layer 43, so that the photodiode 41 of the pixel 20U is substantially decentered in the −Y direction from the center of the exit pupil of the photographing lens 2. The light flux from the light is selectively received and photoelectrically converted.

  FIG. 9A is a schematic plan view schematically showing the main part of the AF pixel 20D, and FIG. 9B is a schematic cross-sectional view taken along line Y3-Y4 in FIG. 9A. The AF pixel 20D is different from the imaging pixel 20A in that in the AF pixel 20D, the light shielding layer 43 has a square concentric with the optical axis O of the microlens 42 of the AF pixel 20D (same as the opening 43a). In place of the rectangular opening 43e that is exactly half the size of the lower (−Y side) size of the square (size square) and cyan color instead of the R, G, B color filters 50R, 50G, 50B. The only difference is that the (Cy) color filter 50Cy is provided. In the pixel 20D, since the opening 43e is formed in the light shielding layer 43, the photodiode 41 of the pixel 20D is from the region of the exit pupil substantially decentered in the + Y direction from the center of the exit pupil of the photographing lens 2. Are selectively received and photoelectrically converted.

  Referring to FIG. 4 again, in the solid-state imaging device 3 according to the present embodiment, a large number of pixels 20 arranged two-dimensionally in the entire effective pixel region 31 are adjacent to each other in the column direction (Y-axis direction). In addition, the pixel blocks are divided into a plurality of pixel blocks each including 2 × 2 pixels 20 arranged adjacent to each other in the row direction (X-axis direction). In FIG. 4, each group of 2 × 2 pixels 20 surrounded by a thick line is one pixel block. In other words, a pixel block composed of 2 × 2 pixels 20 is taken as a unit, and the pixel block is two-dimensionally arranged in the entire effective pixel region 31. Each pixel block is not limited to 2 × 2 pixels 20, and may be m × n pixels, where m and n are each an integer of 2 or more.

  In the present embodiment, for each of all pixel blocks, all 2 × 2 pixels 20 of the pixel block are provided with the same color filter 50 except for the AF pixel 20F. Accordingly, each pixel block outputs color information of one color according to the color of the imaging pixel 20A. In the present embodiment, a signal corresponding to the imaging signal of the four imaging pixels 20A, which is the number of pixels in one pixel block, is used as the imaging signal for one pixel block region. In this embodiment, the pixel block arranged in the entire effective pixel region 31 regards the color of the color filter 50 provided in the imaging pixel 20A of the pixel block as the color of the pixel block. The pixels are arranged according to a Bayer array based on the color of the pixel block.

  In the present embodiment, each of the focus detection areas 32, 36, and 37 extending in the X-axis direction in FIG. 3 is an area of one pixel row, and each focus detection extending in the Y-axis direction in FIG. Each of the areas 33 to 35 is an area of one pixel column. FIG. 4 clearly shows that the focus detection area 32 is an area of one pixel row and the focus detection area 33 is an area of one pixel column.

  In the present embodiment, each pixel block including a part of one of the focus detection areas 32, 36, and 37 extending in the X-axis direction is the pixel 20 (here, the intersection) of the focus detection areas 32 and 33. One pixel block 60 including the pixel 20L) (in the present embodiment, this pixel block 60 is a unique pixel block. Therefore, in order to distinguish it from other pixel blocks, reference numeral 60 is assigned in FIG. 2), two AF pixels 20F (AF pixel 20R and AF pixel 20L) which are arranged in the corresponding focus detection area and make a pair with respect to pupil division, and two imaging pixels 20A Consists of. Each pixel block including a part of any one of the focus detection areas 33 to 35 extending in the Y-axis direction is arranged in the corresponding focus detection area except for the pixel block 60 and is paired with respect to pupil division. AF pixel 20F (AF pixel 20U and AF pixel 20D) and two imaging pixels 20A. The pixel block 60 includes three AF pixels 20F (an AF pixel 20R, an AF pixel 20L, and an AF pixel 20U) arranged in a corresponding focus detection region, and one imaging pixel 20A. Since the pixel block 60 is not provided with the AF pixel 20D paired with the AF pixel 20U, the focus detection signal from the AF pixel 20U of the pixel block 60 cannot actually be used for focus detection. . Therefore, the AF pixel 20U of the pixel block 60 may be replaced with the imaging pixel 20A. Each pixel block that does not include a part of any of the focus detection areas 32 to 37 includes four imaging pixels 20A.

  In this way, in the present embodiment, the AF pixels 20R and 20L are arranged in the same row across two or more pixel blocks arranged in the X-axis direction in each of the focus detection areas 32, 36, and 37. They are arranged in a straight line so as to be sequentially adjacent. Further, the AF pixels 20U and 20D are arranged in a straight line so as to be sequentially adjacent to each other in the same column over two or more pixel blocks arranged in the Y-axis direction in each of the focus detection areas 33 to 35. Yes.

  When detecting the focus adjustment state of the photographic lens 2, a focus detection signal output from the AF pixel 20F is used. Further, at the time of imaging, regarding the pixel block composed of the two AF pixels 20F and the two imaging pixels 20A, the outputs of the two imaging pixels 20A are used as imaging signals for the pixel blocks. That is, first, the imaging signals individually output from the two imaging pixels 20 </ b> A are added up inside or outside the solid-state imaging device 3. However, the two AF pixels 20F do not generate an imaging signal. Therefore, it is approximated that areas where four pixels of the same pixel block are arranged have substantially the same amount of light. Then, the combined imaging signal is further doubled to obtain an imaging signal for four pixels. For the pixel block 60, the imaging signal of one imaging pixel 20A may be quadrupled to obtain an imaging signal for four pixels.

  In other words, in the present solid-state imaging device 3, when the AF pixel 20F is interpolated during imaging, the signal of the imaging pixel 20A adjacent to the AF pixel 20F can be used as an interpolation signal. Therefore, in the present embodiment, it is possible to improve the image quality by improving the accuracy of interpolation related to the AF pixel 20F as compared with the solid-state imaging device in which individual pixels are arranged according to the Bayer arrangement or according to the Bayer arrangement. However, in the present invention, individual pixels may be arranged according to the Bayer arrangement or according to the Bayer arrangement. An example thereof will be described later as a second embodiment.

  Note that regarding the pixel block including the four imaging pixels 20 </ b> A, the imaging signals individually output from the four imaging pixels 20 </ b> A are added together inside or outside the solid-state imaging device 3. . The added signal becomes image information of the pixel block.

  FIG. 10 is a circuit diagram showing 2 × 2 pixels 20 forming one pixel block of the solid-state imaging device 3 in FIG. FIG. 10 shows a pixel block (see FIG. 4) including a part of the focus detection area 33, that is, two AF pixels 20F (AF pixel 20U and AF pixel 20D) and two imaging pixels 20A. Show.

  In the present embodiment, all of the pixels 20 (the imaging pixel 20A, the AF pixel 20R, the AF pixel 20L, the AF pixel 20U, and the AF pixel 20D) have the same circuit configuration. Each pixel has a photodiode 41 as a photoelectric conversion unit that generates and accumulates charges according to incident light, and a floating diffusion (FD) as a charge-voltage conversion unit that receives the charges and converts the charges into voltages. 81, a pixel amplifier 82 as an amplifier that outputs a signal corresponding to the potential of the FD 81, a transfer transistor 83 as a charge transfer unit that transfers charges from the photodiode 41 to the FD 81, and a reset unit that resets the potential of the FD 81 And a selection transistor 85 as a selection unit for selecting the pixel 20. In FIG. 10, Vdd is a power source. The circuit configuration of the pixel 20 is general as a circuit configuration of a unit pixel of the CMOS solid-state imaging device.

  In this embodiment, the transfer transistor 83, the pixel amplifier 82, the reset transistor 84, and the selection transistor 85 are all configured by NMOS transistors.

  The gate electrode of the transfer transistor 83 of each pixel 20 is commonly connected to each pixel row, and a drive signal φTG is supplied from the vertical scanning circuit 21 via the drive wiring 23. The gate electrode of the selection transistor 85 of each pixel 20 is commonly connected to each pixel row, and a drive signal φS is supplied from the vertical scanning circuit 21 via the drive wiring 23. The gate electrode of the reset transistor 84 of each pixel 20 is commonly connected to each pixel row, and a drive signal φFDR is supplied from the vertical scanning circuit 21 via the drive wiring 23.

  FIG. 11 is a timing chart illustrating an operation example of the solid-state imaging device 3. This example shows an example of a rolling shutter. Here, the description will be made by outputting an imaging signal. However, when a focus detection signal is output, only the area (row, column) to be read is limited and is basically the same.

  First, while φTG is high and low while φFDR of the selected row is high, the photodiode 41 is reset. After a predetermined time has elapsed, φS is set high and the selection transistor 85 in the selected row is turned on. φFDR is set high for a certain period from the start of φS high, the level of FD81 is reset to the reference level, and then φFDR is set low. Next, a level (dark level) corresponding to the reference level of the FD 81 is accumulated in the CDS circuit 27 from the pixel amplifier 82 via the vertical signal line 25.

  Next, φTG is set to high and low again. Thereby, the electric charge accumulated in the photodiode 41 is transferred to the FD 81. Thereafter, a signal having a level corresponding to a signal obtained by superimposing the reference level and the signal due to the electric charge is accumulated in the CDS circuit 27 from the pixel amplifier 82 via the vertical signal line 25. Then, the CDS circuit 27 outputs an imaging signal obtained by taking the difference between the signal accumulated here and the previous dark level. Then, the imaging signals for each column are sequentially output to the horizontal signal line.

  Thereafter, the next row is selected and signals are output in the same manner.

  FIG. 12 is a timing chart showing another operation example of the solid-state imaging device 3. In this example, all pixels are exposed simultaneously. First, φTG is set to high at the same time in all rows while φFDR is set to high for all rows. As a result, the charges accumulated in the photodiodes 41 of all the pixels 20 are simultaneously reset. Note that the exposure time is the time from when φTG goes low until φTG goes high again.

  After a predetermined time has elapsed, φS of the selected row is set high. Next, φTG is set to high and low again (this operation is performed simultaneously for all rows). As a result, the charges accumulated in the photodiodes 41 are transferred to the FD 81 simultaneously for all the rows. In the selected row, a signal having a level corresponding to the signal due to the charge is accumulated in the CDS circuit 27 from the pixel amplifier 82 via the vertical signal line 25. Here, the CDS circuit 27 does not perform the correlated double sampling process (CDS process) using the dark level, but is simply used as a circuit for temporarily storing a signal having a level corresponding to the signal based on the charge. Then, the imaging signals for each column are sequentially output to the horizontal signal line.

  Thereafter, the next row is selected and signals are output in the same manner.

  Here, for the sake of simplification, the CDS process is not performed. However, it is needless to say that it is preferable to perform the CDS process even when all pixels are exposed simultaneously. In this case, for example, as disclosed in Patent Document 1 (Japanese Patent Application Laid-Open No. 11-177076), the charge from the photodiode 41 is temporarily accumulated between the photodiode 41 and the FD 81. A storage unit (capacitance) is provided, and instead of the transfer transistor 83, a first transfer transistor that transfers charges from the photodiode 41 to the storage unit, and a second transfer transistor that transfers charges from the storage unit to the FD 81 May be provided.

  Here, an example of the operation of the electronic camera 1 according to the present embodiment will be described.

  When the half-press operation of the release button of the operation unit 9a is performed, the microprocessor 9 in the electronic camera 1 drives the imaging control unit 4 in synchronization with the half-press operation. The imaging control unit 4 reads an imaging signal for subject confirmation from all the pixels of the imaging pixel 20A or a predetermined pixel and stores it in the memory 7 by a known method predetermined for confirming the subject. At this time, when all the pixels are read out, for example, the same operation as that shown in FIG. 11 or 12 is performed. Then, the image processing unit 13 recognizes the subject from the signal using image recognition technology. For example, in the face recognition mode, a face is recognized as a subject. At this time, the image processing unit 13 obtains the position and shape of the subject.

  Thereafter, the microprocessor 9 should be used for focus detection, which is optimal for accurately detecting the focus adjustment state with respect to the subject from the focus detection regions 32 to 37 according to the position and shape of the subject obtained previously. A focus detection area corresponding to the autofocus line sensor is set. Further, the microprocessor 9 sets shooting conditions (aperture, focus adjustment state, shutter time, etc.) for focus detection based on the recognition result and the like.

  Subsequently, the microprocessor 9 operates the lens control unit 2a so as to satisfy the previously set conditions such as the aperture, and the AF pixels in the focus detection area set previously under the conditions such as the previously set shutter time. A focus detection signal is read out and stored in the memory 7 by driving the imaging control unit 4 according to the coordinates of the 20F pixel column. At this time, the focus detection signal is read out by the same operation as that shown in FIG. 11 or FIG.

  Next, the microprocessor 9 picks up the focus detection signals from the AF pixels 20F in the focus detection area set in advance from among the signals of all the pixels acquired and stored in the memory 7, The focus detection calculation unit 10 is made to calculate the defocus amount by causing the focus detection calculation unit 10 to perform calculation (focus adjustment state detection processing) according to the pupil division phase difference method based on the signal.

  Next, the microprocessor 9 causes the lens control unit 2a to adjust the photographing lens 2 so that the in-focus state is obtained according to the previously calculated defocus amount. Subsequently, the microprocessor 9 sets shooting conditions (aperture, shutter time, etc.) for the main shooting.

  Next, the microprocessor 9 operates the lens control unit 2a so as to satisfy the conditions such as the aperture set for the main shooting, and for the main shooting in synchronism with the full pressing operation of the release button of the operation unit 9a. By driving the imaging control unit 4 under the conditions such as the shutter time set to, the image signal is read out and actual imaging is performed. At this time, the imaging signal is read out by the same operation as that shown in FIG. 11 or FIG. The imaging control unit 4 accumulates the imaging signal in the memory 7.

  Next, the microprocessor 9 causes the image processing unit 13 to perform processing (including interpolation processing) for obtaining imaging signals for four pixels for each pixel block as described above, and this is stored in the memory 7 as an image signal. Accumulate.

  Thereafter, the microprocessor 9 performs a desired process in the image processing unit 13 or the image compression unit 12 as necessary based on a command from the operation unit 9a, and outputs a processed signal to the recording unit to the recording medium 11a. Record.

  In the present embodiment, as described above, the imaging pixel 20A is provided with any one of the red color filter 50R, the green color filter 50G, and the blue color filter 20B, whereas the AF pixel 20F ( 20R, 20L, 20U, and 20D) are provided with a cyan color filter 50Cy as an optical filter having light transmission characteristics different from any of these color filters 50R, 50G, and 50B. Examples of light transmission characteristics (spectral sensitivity characteristics) of these color filters 50R, 50G, 50B, and 50Cy are shown in FIGS. 13 to 16, respectively.

  As can be seen from FIGS. 13 and 16, the cyan color filter 50Cy has a much lower transmittance of long-wavelength light near the red color than the red color filter 50R. Therefore, in the AF pixel 20F provided with the cyan color filter 50Cy, it is incident on the photodiode 41 as compared with the case where no color filter is provided or when the red color filter 50R is provided instead of the cyan color filter 50Cy. Long-wave components are hardly included in the light, and incident light is photoelectrically converted relatively near the silicon surface, and signal charges are hardly generated in the deep part of the silicon substrate. Therefore, according to the present embodiment, it is difficult to cause a situation in which charges generated in the AF pixel 20F are drifted toward the adjacent imaging pixel 20A by the incident light having a long wavelength. In other words, the charge mixed from the AF pixel 20F to the adjacent imaging pixel 20A is reduced, and crosstalk from the AF pixel 20 to the adjacent imaging pixel 20A can be suppressed. For this reason, this charge is not trapped in the charge storage layer of the photodiode 41 of the adjacent imaging pixel 20A, and the imaging signal does not increase. Therefore, the magnitude of the signal between the imaging signal obtained from the imaging pixel 20A in the region other than the vicinity of the AF pixel 20F and the imaging signal obtained from the imaging pixel 20A in the region near the AF pixel 20F is large. Therefore, a high quality image can be obtained.

  As can be seen from FIG. 16, the cyan color filter 50Cy has a relatively high transmittance in a relatively wide wavelength range from blue to green. Therefore, according to the present embodiment, the amount of incident light on the AF pixel 20F is increased as compared with the case where the blue color filter 50B or the green color filter 50G is provided in the AF pixel 20F instead of the cyan color filter 50Cy. As a result, the accuracy of focus detection increases.

  Thus, according to the present embodiment, since the cyan color filter 50Cy is provided in the AF pixel 20F, the effect of increasing the accuracy of focus detection by increasing the amount of incident light on the AF pixel 20F (hereinafter referred to as the following). , “Referred to as“ increased incident light amount for AF ”) to some extent while reducing the crosstalk from the AF pixel 20 to the adjacent imaging pixel 20A (hereinafter referred to as“ crosstalk ”). A reduction effect ”).

  Prior to the solid-state imaging device disclosed in Patent Document 4 described above, the effect of increasing the incident light amount for AF is overlooked. According to this, the AF pixel 20 is provided in the imaging pixel 20A. One of the R, G, and B color filters 50R, 50G, and 50B is provided. On the other hand, according to Patent Document 4 focusing on the AF incident light amount increasing effect, the AF pixel 20 is not provided with any color filter. As described above, according to the conventional technical common sense, the “crosstalk reduction effect” is completely overlooked, and the R, G, B color filter 50R provided in the imaging pixel 20A is included in the AF pixel 20. , 50G, 50B, or no color filter is provided. Conventionally, it has not been conceivable to provide the AF pixel 20F with color filters other than the R, G, B color filters 50R, 50G, 50B provided in the imaging pixel 20A.

  When a red color filter 50R is provided in the AF pixel 20F instead of the cyan color filter 50Cy, the red color filter 50R cuts components in the wavelength range from blue to green and transmits long wavelength light as shown in FIG. Therefore, not only the effect of increasing the incident light quantity for AF but also the effect of reducing crosstalk cannot be obtained.

  When the blue color filter 50B or the green color filter 50G is provided in the AF pixel 20F in place of the cyan color filter 50Cy, these color filters 50B and 50G have a blue or green wavelength range as shown in FIGS. Since the component is selectively transmitted, the effect of increasing the incident light amount for AF cannot be obtained at all although the effect of reducing the crosstalk is obtained.

  If no color filter is provided in the AF pixel 20F, components in any wavelength region are not cut, so that a large AF incident light amount increasing effect can be obtained, but no crosstalk reducing effect can be obtained.

  As described above, when the conventional technical common sense is followed, it becomes an alternative state between the effect of reducing the crosstalk and the effect of increasing the incident light amount for AF, and the two cannot be balanced. is there. In contrast, in the present embodiment, a new focus is placed on the effect of reducing crosstalk that has been overlooked so far, and a cyan color filter 50 </ b> Cy is provided in the AF pixel 20 </ b> F, so that crosstalk that has a trade-off relationship is achieved. The balance between the reduction effect and the AF incident light increase effect is achieved.

  As can be seen from the above description, in order to balance both the crosstalk reduction effect and the AF incident light amount increase effect and to enhance both, ideally, the optical filter provided in the AF pixel 20F is It is preferable that the transmittance of the component in the wavelength region higher than the predetermined cutoff wavelength near red is zero and the transmittance of the component in the wavelength region lower than the cutoff wavelength is 100%. . In the present embodiment, a cyan color filter 50Cy is provided in the AF pixel 20F as an optical filter having a light transmission characteristic relatively close to such an ideal light transmission characteristic.

  However, compared to the case where the blue color filter 50B or the green color filter 50G is provided in place of the cyan color filter 50Cy on the AF pixel 20F, a larger incident light amount increasing effect can be obtained, while the cyan color filter 50Cy is provided on the AF pixel 20F. If a large crosstalk reduction effect is obtained as compared with the case where the red color filter 50R is provided instead of the above, it is preferable as compared with the conventional two-company selection state. Therefore, in the present invention, it is only necessary to satisfy the conditions for realizing such a state, and the optical filter provided in the AF pixel 20F is not necessarily limited to the cyan color filter 50Cy.

  As an example of such a condition, the integrated value of the optical filter provided in the AF pixel 20F with respect to the wavelength of transmittance in the wavelength region of 400 nm to 600 nm is the integrated value of the green color filter 50G and the blue color filter 50B. The integral value relating to the wavelength of transmittance in the wavelength region of 600 nm to 700 nm of the optical filter is smaller than the integral value of the red color filter 50R. Can do. As can be seen from FIGS. 13 to 16, the cyan color filter 50Cy satisfies this condition. At this time, in order to further enhance the crosstalk reduction effect, it is more preferable that the transmittance of the optical filter in the wavelength region of 600 nm or more and 650 nm or less is 20% or less. As can be seen from FIG. 16, the cyan color filter 50Cy matches this. In order to further enhance the effect of increasing the amount of incident light, the transmittance of the optical filter in the wavelength region of 410 nm or more and 550 nm or less is more preferably 40% or more. As can be seen from FIG. 16, the cyan color filter 50Cy matches this.

  As another example of the conditions as described above, the transmittance of the optical filter provided in the AF pixel 20F in the wavelength range of 420 nm to 500 nm is 30% or more, and the optical filter has a wavelength range of 590 nm to 650 nm. It can be mentioned that the transmittance at 30 is 30% or less. At this time, in order to further enhance the crosstalk reduction effect, the transmittance of the optical filter in the wavelength range of 570 nm to 650 nm is more preferably 30% or less, and the optical filter in the wavelength range of 550 nm to 650 nm is more preferable. The transmittance of is more preferably 30% or less. In order to further enhance the effect of increasing the amount of incident light, the transmittance of the optical filter in the wavelength region of 410 nm to 510 nm is more preferably 30% or more, and the optical filter in the wavelength region of 400 nm to 520 nm is more preferable. More preferably, the transmittance is 30% or more.

  [Second Embodiment]

  FIG. 17 is a partially enlarged schematic plan view schematically showing the arrangement of pixels of the solid-state imaging device 70 used in the electronic camera according to the second embodiment of the present invention, and corresponds to FIG. . 17, elements that are the same as or correspond to those in FIG. 4 are given the same reference numerals, and redundant descriptions thereof are omitted.

  This embodiment is different from the first embodiment only in that a solid-state image sensor 70 is basically used instead of the solid-state image sensor 3. The only difference between the solid-state imaging device 70 and the solid-state imaging device 3 is that the individual imaging pixels 20A are arranged according to the Bayer array.

  Also in this embodiment, the same advantages as those in the first embodiment can be obtained.

  [Third Embodiment]

  FIG. 18 is a partially enlarged schematic plan view schematically showing the arrangement of pixels of the solid-state imaging device 90 used in the electronic camera according to the third embodiment of the present invention, and corresponds to FIG. . 18, elements that are the same as or correspond to those in FIG. 4 are given the same reference numerals, and redundant descriptions thereof are omitted.

  This embodiment is different from the first embodiment only in that a solid-state image sensor 90 is basically used instead of the solid-state image sensor 3. The solid-state image sensor 90 is different from the solid-state image sensor 3 only in the points described below.

  In the solid-state imaging device 90, in the solid-state imaging device 3, all the AF pixels 20R and 20L are replaced by AF pixels 20H, and all the AF pixels 20U and 20D are respectively replaced by AF pixels 20V.

  FIG. 19A is a schematic plan view schematically showing the main part of the AF pixel 20H, and FIG. 19B is a schematic cross-sectional view taken along line X7-X8 in FIG. 19A. 20A is a schematic plan view schematically showing the main part of the AF pixel 20V, and FIG. 20B is a schematic cross-sectional view taken along line Y5-Y6 in FIG. 20A. FIG. 21 is a circuit diagram showing 2 × 2 pixels forming one pixel block of the solid-state imaging device 90. FIG. 21 illustrates a pixel block including a part of the focus detection area 33 (see FIG. 18), that is, two AF pixels 20V and two imaging pixels 20A. 19 to 21, elements that are the same as or correspond to those in FIGS. 5, 6, and 10 are given the same reference numerals, and redundant descriptions thereof are omitted.

  The AF pixel 20H and the AF pixel 20V have the same circuit configuration. The difference between the AF pixels 20H and 20V in terms of circuit configuration from the imaging pixel 20A is that, instead of one photodiode 41, two photodiodes 41a and 41b that are divided into two are provided. Accordingly, instead of one transfer transistor 83, only two transfer transistors 83a and 83b that can operate independently from each other are provided. The transfer transistor 83a transfers charge from the photodiode 41a to the FD 81, and the transfer transistor 83b transfers charge from the photodiode 41b to the FD 81.

  As understood from FIGS. 19, 20, and 5, in the AF pixel 20 </ b> H, the photodiodes 41 a and 41 b are configured by dividing a photodiode corresponding to the photodiode 41 into −X side and + X side. ing. In the AF pixel 20V, the photodiodes 41a and 41b are configured by dividing a photodiode corresponding to the photodiode 41 into + Y side and −Y side.

  As shown in FIGS. 19 and 20, the AF pixels 20H and 20V are provided with a cyan color filter 50Cy as in the case of 20R, 20L, 20U, and 20D.

  The transfer transistor 83 of the imaging pixel 20A and the gate electrode of one of the transfer transistors 83a of the AF pixels 20V and 20H are connected in common to each pixel row, and the drive signal φTGA is connected from the vertical scanning circuit 21 via the drive wiring 23. Is supplied. The gate electrodes of the other transfer transistors 83b of the AF pixels 20V and 20H are connected in common to each pixel row, and a drive signal φTGB is supplied from the vertical scanning circuit 21 via the drive wiring 23.

  FIG. 22 is a timing chart showing an operation example of the solid-state image sensor 90. In this example, an imaging signal is obtained in the case of a rolling shutter. This operation example is the same as the operation shown in FIG. 11 described in the first embodiment. φTGA is the same as φTG in FIG. In this example, since signals from the AF pixels 20H and 20V are not used and have no meaning, φTGB may be arbitrary. Therefore, φTGB is not shown in FIG.

  FIG. 23 is a timing chart showing another example of the operation of the solid-state imaging device 90. In this example, a focus detection signal is obtained in the case of a rolling shutter. The operation shown in FIG. 23 is different from the operation shown in FIG. 22 in that signals are separately read from the two photodiodes 41a and 41b. That is, in the operation shown in FIG. 23, while φS is high and selected, the charge of one photodiode 41a is read and the charge of the other photodiode 41b is then read for the AF pixels 20H and 20V. It has become.

  Also in this embodiment, the same advantages as those in the first embodiment can be obtained. Further, according to the present embodiment, since the AF pixels 20H and 20V each having two photodiodes 41a and 41b are used as the AF pixels, the distribution density of the places where the focus detection signals are obtained increases. . Therefore, the accuracy of focus detection is further increased.

  Similarly to the case where the solid-state image pickup device 90 in the second embodiment is obtained by modifying the solid-state image pickup device 3 in the first embodiment, all the AF-use elements are used in the solid-state image pickup device 70 in the second embodiment. The pixels 20R and 20L may be replaced with AF pixels 20H, respectively, and all the AF pixels 20U and 20D may be replaced with AF pixels 20V, respectively.

  Although the embodiments of the present invention have been described above, the present invention is not limited to these embodiments.

It is a schematic block diagram which shows the electronic camera as an imaging device which concerns on the 1st Embodiment of this invention. It is a circuit diagram which shows schematic structure of the solid-state image sensor 3 in FIG. It is a schematic plan view which shows typically the solid-state image sensor 3 in FIG. FIG. 4 is a schematic enlarged view in which the vicinity of an intersection of a focus detection region in FIG. 3 is enlarged. It is a figure which shows typically the principal part of the pixel for imaging in FIG. It is a figure which shows typically the principal part of the predetermined AF pixel in FIG. It is a figure which shows typically the principal part of the other predetermined AF pixel in FIG. It is a figure which shows typically the principal part of the other predetermined AF pixel in FIG. It is a figure which shows typically the principal part of the other predetermined AF pixel in FIG. FIG. 2 is a circuit diagram showing 2 × 2 pixels forming one pixel block of the solid-state imaging device in FIG. 1. 2 is a timing chart illustrating an operation example of the solid-state imaging device in FIG. 1. 6 is a timing chart illustrating another operation example of the solid-state imaging device in FIG. 1. FIG. 5 is a diagram illustrating an example of light transmission characteristics of a red color filter provided in the imaging pixel in FIG. 4. FIG. 5 is a diagram illustrating an example of light transmission characteristics of a green color filter provided in the imaging pixel in FIG. 4. FIG. 5 is a diagram illustrating an example of light transmission characteristics of a blue color filter provided in the imaging pixel in FIG. 4. FIG. 5 is a diagram illustrating an example of light transmission characteristics of a cyan color filter provided in the imaging pixel in FIG. 4. It is a partially expanded schematic plan view which shows typically the pixel arrangement | positioning of the solid-state image sensor used with the electronic camera by the 2nd Embodiment of this invention. It is a partially expanded schematic plan view which shows typically the pixel arrangement | positioning of the solid-state image sensor used with the electronic camera by the 3rd Embodiment of this invention. It is a figure which shows typically the principal part of the predetermined AF pixel in FIG. It is a figure which shows typically the principal part of the other predetermined AF pixel in FIG. FIG. 19 is a circuit diagram showing 2 × 2 pixels forming one pixel block of the solid-state imaging device shown in FIG. 18. It is a timing chart which shows the operation example of the solid-state image sensor shown in FIG. 19 is a timing chart illustrating another operation example of the solid-state imaging device illustrated in FIG. 18.

Explanation of symbols

3 Solid-state imaging device 20A Imaging pixels 20R, 20L, 20U, 20D AF pixels 50R Red color filter 50G Green color filter 50B Blue color filter 50Cy Cyan color filter 50

Claims (7)

A solid-state imaging device that photoelectrically converts a subject image formed by an optical system,
A plurality of pixels having a photoelectric conversion unit that is two-dimensionally arranged and each generates and accumulates charges according to incident light,
The plurality of pixels output a plurality of imaging pixels that output an imaging signal for forming an image signal indicating the subject image, and a focus detection signal for detecting a focus adjustment state of the optical system. A plurality of focus detection pixels,
The imaging pixels are divided into first to third groups,
The imaging pixels of the first group are provided with a red color filter,
A green color filter is provided on the imaging pixels of the second group,
The imaging pixels of the third group are provided with a blue color filter,
The focus detection pixel is provided with an optical filter having a light transmission characteristic different from any of the red color filter, the green color filter, and the blue color filter,
The transmittance of the optical filter in the wavelength region of 420 nm or more and 500 nm or less is 30% or more,
The transmittance of the optical filter in the wavelength region of 590 nm or more and 650 nm or less is 30% or less.
A solid-state imaging device. A solid-state imaging device that photoelectrically converts a subject image formed by an optical system,
A plurality of pixels having a photoelectric conversion unit that is two-dimensionally arranged and each generates and accumulates charges according to incident light,
The plurality of pixels output a plurality of imaging pixels that output an imaging signal for forming an image signal indicating the subject image, and a focus detection signal for detecting a focus adjustment state of the optical system. A plurality of focus detection pixels,
The imaging pixels are divided into first to third groups,
The imaging pixels of the first group are provided with a red color filter,
A green color filter is provided on the imaging pixels of the second group,
The imaging pixels of the third group are provided with a blue color filter,
The focus detection pixel is provided with an optical filter having a light transmission characteristic different from any of the red color filter, the green color filter, and the blue color filter,
The integral value related to the wavelength of transmittance in the wavelength region of 400 nm to 600 nm of the optical filter is larger than both the integral value of the green color filter and the integral value of the blue color filter,
The integral value related to the wavelength of transmittance in the wavelength region of 600 nm to 700 nm of the optical filter is smaller than the integral value of the red color filter,
A solid-state imaging device.   3. The solid-state imaging device according to claim 2, wherein a transmittance of the optical filter in a wavelength region of 600 nm to 650 nm is 20% or less.   4. The solid-state imaging device according to claim 2, wherein a transmittance of the optical filter in a wavelength region of 410 nm or more and 550 nm or less is 40% or more.   The solid-state imaging device according to claim 1, wherein the optical filter is a cyan color filter. A solid-state imaging device that photoelectrically converts a subject image formed by an optical system,
A plurality of pixels having a photoelectric conversion unit that is two-dimensionally arranged and each generates and accumulates charges according to incident light,
The plurality of pixels output a plurality of imaging pixels that output an imaging signal for forming an image signal indicating the subject image, and a focus detection signal for detecting a focus adjustment state of the optical system. A plurality of focus detection pixels,
The imaging pixels are divided into first to third groups,
The imaging pixels of the first group are provided with a red color filter,
A green color filter is provided on the imaging pixels of the second group,
The imaging pixels of the third group are provided with a blue color filter,
The focus detection pixel is provided with a cyan color filter.
A solid-state imaging device. A solid-state imaging device according to any one of claims 1 to 6,
A detection processing unit that outputs a detection signal indicating a focus adjustment state of the optical system based on the focus detection signal from at least some of the plurality of focus detection pixels;
An adjusting unit that adjusts the focus of the optical system based on the detection signal from the detection processing unit;
An imaging apparatus comprising:

Images