JP2013045907A - Imaging element and imaging device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To achieve a structure capable of preventing sensitivity reduction of an imaging signal influenced by a pixel separation region and degradation of incident angle characteristics in an imaging element having a divided pixel.SOLUTION: In an imaging element having a photoelectric conversion part, divided in a plurality, and sharing a microlens, an optical means which guides light incident on the microlens to each photoelectric conversion part is provided at a light incident side of each photoelectric conversion part.

Description

  The present invention relates to an imaging device having a plurality of divided photoelectric conversion units sharing a microlens.

  2. Description of the Related Art Conventionally, there are many imaging devices such as electronic cameras that record and reproduce still images and moving images captured by a solid-state imaging device such as a CCD or CMOS using a memory card having a solid-state memory device as a recording medium.

  Patent Documents 1 and 2 propose a device in which the photoelectric conversion units of some or all of the pixels constituting a solid-state imaging device mounted on an imaging apparatus are divided into a plurality of pixels.

  Applications of such an image sensor include performing pupil-focusing focus detection based on output signals from the respective image signals of the divided photoelectric conversion units, and generating stereoscopic images. It is done. Of course, by adding the outputs of the divided pixels, it can be used as a normal imaging signal.

  In addition, as another example of the technology related to the solid-state imaging device mounted on the imaging device, an optical waveguide having a large aperture ratio on the light incident side is provided between the light incident surface and the photoelectric conversion means, thereby improving the light collection characteristics. An image sensor is proposed in Patent Document 4 and the like.

JP 2003-244712 A Japanese Patent Laid-Open No. 06-163866 JP 2009-158800 A JP 05-283661 A

However, shooting as a normal imaging signal in an imaging apparatus using an individual imaging device having divided pixels as described above has the following problems. That is,
When configuring divided pixels as in Patent Documents 1 and 2, various pixel components may be arranged between the divided pixels. For example, when it is desired to increase the area of the photodiode to improve sensitivity, a floating diffusion (hereinafter referred to as FD) or output signal line is not arranged for each divided pixel, but an FD shared by a plurality of divided pixels is used. The structure which does is preferable. At this time, the shared FD is desirably arranged at the center of each divided pixel. Thus, in order to arrange pixel components such as FD between the divided pixels, there is a separation region having no sensitivity between the photodiodes of the divided pixels.

  Even if the components arranged between the divided pixels are eliminated, it is difficult to completely eliminate the gap between the photodiodes of the divided pixels because of the manufacturing accuracy and alignment accuracy of the pixel portion.

  For these reasons, a separation region for separating each divided pixel is necessary between the plurality of divided pixels constituting the pixel used for imaging.

  However, since there is a separation area that does not have sensitivity, the output signal of each divided pixel is added and the pixel signal is used as one imaging signal, compared to the case where the pixel is not divided. Sensitivity is reduced by the area.

  In addition, since the separation region has no sensitivity, the light beam reaching the separation region does not appear in the output signal, but the separation region with respect to the amount of light received by the pixel depends on the state of the photographing lens, the aperture amount, the angle of incident light, etc. The amount of light that reaches it fluctuates. For this reason, an aperture dependency, an incident angle dependency, or the like occurs in the output signal.

  In order to reduce such sensitivity degradation of the divided pixels, a method of condensing light by arranging an inner lens in front of the photodiode of the divided pixel as in Patent Document 2 has been proposed. However, because of the constraints on the shape and curvature of the intralayer lens, it is difficult to focus all the light beams incident on the pixel on the photodiode of one of the divided pixels while avoiding the separation region. Sensitivity is reduced as compared with the case of a configuration in which no division is performed.

  In addition, a method of providing a gap in front of the divided pixels has been proposed for the purpose of separating incident light to the divided pixels as in Patent Document 3. However, since the gap itself arranged in front of the divided pixels corresponds to the separation region, the sensitivity is deteriorated and the incident angle characteristic is deteriorated as compared with the configuration in which the pixels are not divided.

  The present invention has been made in view of the above problems, and an object of the present invention is to realize a structure that does not cause a decrease in sensitivity of an image pickup signal or deterioration in incident angle characteristics due to the influence of a pixel separation region in an image pickup device having divided pixels. is there.

  In order to solve the above-described problems and achieve the object, the present invention provides an image sensor having a plurality of photoelectric conversion units sharing a microlens, wherein the microlens is disposed on a light incident side of each photoelectric conversion unit. Optical means for guiding the light incident on each of the photoelectric conversion units is provided.

  According to the present invention, it is possible to realize a structure that does not cause a decrease in sensitivity of an imaging signal, deterioration in incident angle characteristics, and the like due to the influence of a pixel separation region in an imaging element having divided pixels.

1 is a block diagram showing a configuration of an imaging apparatus according to an embodiment of the present invention. The figure which shows the pixel arrangement | sequence of the image pick-up element which concerns on this embodiment. FIG. 3 is a cross-sectional view of the image sensor according to the first embodiment. 1 is a schematic cross-sectional view of a part of an image sensor according to an embodiment. The circuit diagram of the image sensor concerning this embodiment. 4 is a timing chart showing first drive timing according to the present embodiment. The timing chart which shows the 2nd drive timing which concerns on embodiment of this invention.

  Hereinafter, embodiments for carrying out the present invention will be described in detail. The embodiment described below is an example for realizing the present invention, and should be appropriately modified or changed according to the configuration and various conditions of the apparatus to which the present invention is applied. It is not limited to the embodiment. Moreover, you may comprise combining suitably one part of each embodiment mentioned later.

  <Apparatus Configuration> With reference to FIG. 1, the configuration of an imaging apparatus according to an embodiment of the present invention will be described.

  In FIG. 1, an optical system 101 includes a lens and a diaphragm. The shutter 102 is a mechanical shutter that operates mechanically (hereinafter, mechanical shutter). The imaging element 103 is a CMOS sensor that converts incident light that has passed through the optical system 101 into an electrical signal. The photoelectric conversion unit 104 that converts incident light into an electrical signal inside the imaging element 103 and the electrical inside the imaging element 103. A signal amplifying circuit 105 for amplifying the signal.

  The analog signal processing circuit 106 performs analog signal processing on the image signal output from the image sensor 103. The analog signal processing circuit 106 includes a CDS circuit 107 that performs correlated double sampling inside the circuit, a signal amplifier 108 that amplifies the analog signal, a clamp circuit 109 that performs horizontal OB clamping, and an A / D conversion that converts the analog signal into a digital signal. A container 110.

  The timing signal generation circuit 111 generates a signal for operating the image sensor 103 and the analog signal processing circuit 106. The drive circuit 112 drives the optical system 101 and the mechanical shutter 102.

  The digital signal processing circuit 113 performs digital signal processing necessary for captured image data. The digital signal processing circuit 113 includes an image correction circuit 114 that performs necessary correction processing on image data in the circuit, a signal amplification circuit 115 that amplifies the digital signal, and an image processing circuit 116 that performs necessary image processing on the image data. Have.

  The image memory 117 stores image data that has undergone signal processing. The recording medium 118 is detachable from the imaging apparatus, and the recording circuit 119 records the image data subjected to signal processing on the recording medium 118. The display device 120 includes an LCD or the like for displaying signal-processed image data, and the display circuit 121 displays an image on the display device 120.

  The system control unit 122 controls the entire imaging apparatus. The non-volatile memory (ROM) 123 stores a control program executed by the system control unit 122, control data such as parameters and tables used when executing the program, and correction data such as a scratch address. A volatile memory (RAM) 124 stores a control program, control data, and correction data transferred from the nonvolatile memory 123, and is used when the system control unit 122 controls the imaging apparatus.

  The temperature detection circuit 125 detects the temperature of the image sensor 103 and its peripheral circuits. The accumulation time setting unit 126 sets the charge accumulation time of the image sensor 103. The shooting mode setting unit 127 performs shooting condition settings such as ISO sensitivity setting, and switching between still image shooting and moving image shooting.

  <Description of Operation> Next, the photographing operation and the reproducing operation by the image pickup apparatus having the configuration shown in FIG. 1 will be described.

  Prior to the shooting operation, necessary programs, control data, and correction data are transferred from the nonvolatile memory 123 and stored in the volatile memory 124 when the system control unit 122 is activated, such as when the power is turned on. These programs and data are used for control of the system control unit 122, and additional programs and data are transferred from the memory 123 to the memory 124 as necessary, or the system control unit 122 directly transfers the nonvolatile memory 123. The data is read and used.

  First, the optical system 101 drives a diaphragm and a lens in accordance with a control signal from the system control unit 122 to form a subject image set to an appropriate brightness on the image sensor 103. Next, when taking a still image, the mechanical shutter 102 shields the image sensor 103 in accordance with the charge accumulation operation of the image sensor 103 so that a necessary exposure time is obtained in accordance with a control signal from the system controller 122. To be driven. In this case, when the image sensor 103 has an electronic shutter function, the necessary exposure time may be ensured in combination with the mechanical shutter 102. Further, the mechanical shutter 102 is maintained in the open state so that the image sensor 103 is always exposed during the photographing by the control signal from the system control unit 122 at the time of moving image photographing.

  The image sensor 103 is driven with a drive pulse based on an operation pulse generated by the timing signal generation circuit 111 controlled by the system control unit 122. The photoelectric conversion unit 104 of the image sensor 103 converts the subject image into an electrical signal by photoelectric conversion, and the signal amplification circuit 105 multiplies the gain of the amplification factor set according to the amount of incident light to the electrical signal and outputs it as an analog image signal.

  The analog image signal output from the image sensor 103 is subjected to an operation pulse generated by the timing signal generation circuit 111 controlled by the system control unit 122. In the analog signal processing circuit 106, the CDS circuit 107 removes clock synchronization noise. The PGA circuit 108 multiplies the gain set in accordance with the amount of incident light, the clamp circuit 109 clamps the signal output in the horizontal OB region as a reference voltage, and the A / D converter 110 converts the digital image signal into a digital image signal. .

  Next, for the digital image signal output from the analog signal processing circuit 106, the digital signal processing circuit 113 controlled by the system control unit 122 performs image processing such as color conversion, white balance, and gamma correction, and resolution conversion processing. Image compression processing is performed. First, the image correction circuit 114 performs various image correction processes such as scratch correction and dark shading correction. Next, the signal amplification circuit 115 multiplies the gain set in accordance with the amount of incident light, and the image processing circuit 116 performs various types of image processing such as image processing such as color conversion, white balance, and gamma correction, resolution conversion processing, and image compression processing. Process.

  The image memory 117 temporarily stores a digital image signal during signal processing, or stores image data that is a digital image signal subjected to signal processing.

  The image data signal-processed by the digital signal processing circuit 113 and the image data stored in the image memory 117 are converted by the recording circuit 119 into a data format suitable for the recording medium 118 (for example, file system data having a hierarchical structure). Is recorded on the recording medium 118. Further, after the resolution conversion process is performed by the digital signal processing circuit 113, the display circuit 121 converts the signal into a signal suitable for the display device 120 (for example, an NTSC analog signal) and displays the signal on the display device 120.

  Here, the digital signal processing circuit 113 may output the digital image signal as it is as image data to the image memory 117 or the recording circuit 119 without performing signal processing by the control signal from the system control unit 122. Further, the digital signal processing circuit 113, when requested by the system control unit 122, information on digital image signals and image data generated in the signal processing process, for example, the spatial frequency of the image, the average value of the designated area, Information such as the data amount of the compressed image or information extracted from the information is output to the system control unit 122. Further, the recording circuit 119 outputs information such as the type and free capacity of the recording medium 118 to the system control unit 122 when requested by the system control unit 122.

  Next, the reproduction operation when image data is recorded on the recording medium 118 will be described.

  In response to a control signal from the system control unit 122, the recording circuit 119 reads image data from the recording medium 118. Similarly, when the image data is a compressed image, the digital signal processing circuit 113 performs decompression processing and stores it in the image memory 117 in response to a control signal from the system control unit 122. The image data stored in the image memory 117 is subjected to resolution conversion processing by the digital signal processing circuit 113, converted to a signal suitable for the display device 120 by the display circuit 121, and displayed on the display device 120.

  <Description of Pixel Arrangement> The pixel arrangement of the image sensor according to this embodiment will be described with reference to FIG.

  In FIG. 2, each region indicated by (0, 0), (1, 0), (0, 1), etc. in the drawing represents one pixel in the image signal. In addition, one microlens is arranged for each pixel in the imaging signal. In the present specification, a unit pixel used for an image pickup signal for each microlens is referred to as an image pickup pixel.

  Moreover, each area | region shown by a and b in a figure is a respectively different photoelectric conversion part. In this specification, each photoelectric conversion unit obtained by dividing the imaging pixel into a plurality of pixels is referred to as a divided pixel. In the embodiment shown in FIG. 2, the imaging pixel is configured by two divided pixels arranged in 2 × 1, and the areas a and b are the same in the positional relationship with the microlens. It means being in the quadrant.

  In addition, the letters “R”, “G”, and “B” written in each area in the drawing represent the hue of the color filter formed on each pixel.

  In the image pickup apparatus using the image pickup device having the pixel arrangement shown in FIG. 2, when generating an image pickup signal, the output of one image pickup pixel having “the sum of output signals of the a and b regions” of each divided pixel is provided. Signal.

  Also, when the output of the image sensor is used as a focus detection signal or a stereoscopic image generation signal, it is used by generating two signals of “a region output signal” and “b region output signal”. To do.

  <Element Cross Section Structure of Each Pixel> The cross section structure of each pixel element shown in FIG. 2 will be described with reference to FIG.

  The pixel shown in FIG. 3 is one image pickup pixel composed of two divided pixels in the image pickup element 103 described in FIG. 2, and the photoelectric conversion unit 402 is divided into two regions (402a and 402b). . A first electrode (not shown) made of polysilicon for transferring charges generated in the photoelectric conversion unit 402 is disposed around the photoelectric conversion unit 402.

  In addition, a second electrode 416 and a third electrode 417 made of aluminum for selectively outputting the transferred charges to the outside are disposed. An interlayer insulating film 415 is disposed between the first electrode and the second electrode 416 and between the second electrode 416 and the third electrode 417. The first electrode and the second electrode 416, and the second electrode 416 and the third electrode 417 are respectively connected by a first plug and a second plug (not shown) made of tungsten. .

  Optical waveguides 445 a and 445 b are formed on the light incident side of the photoelectric conversion unit 402. An interlayer insulating film 415 is disposed on the light incident side of the optical waveguides 445a and 445b. A color filter 441 is formed on the light incident side of the interlayer insulating film 415 with the planarizing layer 444 interposed therebetween.

  A micro lens 442 is formed on the color filter 441 with a planarization layer 443 interposed therebetween. The thickness of the microlens 442 is set so that the lens power is such that the pupil of the photographing lens (not shown) and the upper surfaces of the optical waveguides 445a and 445b (imaging plane α in FIG. 3) have a substantially imaging relationship. .

  Next, light incident on the image sensor 103 according to the present embodiment will be described.

  In the pixel structure shown in FIG. 3, the focus detection light beam incident on the microlens 442 is condensed, partially absorbed by the color filter 441, and condensed near the surfaces (imaging plane α) of the optical waveguides 445a and 445b. The pupil of the imaging lens (not shown) and the surfaces of the optical waveguides 445a and 445b (imaging plane α) are in a substantially imaging relationship by the microlens 442, and the light beam incident on the optical waveguides 445a and 445b is converted into a photoelectric conversion region. 402a and 402b are reached. For this reason, the photoelectric conversion areas 402a and 402b can receive the light flux in the pupil area obtained by back projecting each photoelectric conversion area to the pupil side of the photographing lens.

  The light beams incident on the optical waveguides 445a and 445b are totally reflected on the boundary surfaces between the optical waveguides 445a and 445b and the interlayer insulating film 415 and guided to the photoelectric conversion regions 402a and 402b.

  In the structure of the imaging device described above, the light beam that should be focused on the separation region of the divided pixels, which is originally between the photoelectric conversion regions 402a and 402b, also passes through the optical waveguides 445a and 445b. And 402b can be condensed.

  FIG. 4 is a partial cross-sectional view of the image sensor of the present embodiment.

  In FIG. 4, reference numeral 411 denotes a P-type well, and 412 denotes a gate insulating film composed of a SiO2 film. 414a and 414b are P + layers formed on the surface of the P-type well 411, and constitute the photoelectric conversion regions 402a and 402b together with the n layers 413a and 413b. Reference numerals 403a and 403b denote transfer gates for transferring signal charges generated in the photoelectric conversion regions 402a and 402b to a floating diffusion portion (hereinafter referred to as FD portion) 407. 441 is a color filter, 442 is a microlens (on-chip lens), and the microlens 442 is substantially conjugated with a pupil of an imaging lens (optical system 101) (not shown) and photoelectric conversion regions 402a and 402b of the image sensor 103. In such a shape and position.

  Optical waveguides 445a and 445b are disposed between the photoelectric conversion regions 402a and 402b and the color filter 441 and in the vicinity of or behind the imaging position of the microlens 442, respectively.

  In this pixel, photoelectric conversion regions 402a and 402b are formed in two regions with the FD portion 407 interposed therebetween. Further, transfer gates 403a and 403b for transferring signal charges generated in the photoelectric conversion regions 402a and 402b to the FD unit 407 are formed.

  FIG. 5 is a CMOS circuit diagram constituting the image sensor of the present embodiment.

  In FIG. 5, the imaging element has a configuration in which one floating diffusion layer FD407 is connected to two divided pixels 401. The pixel area of the image sensor 103 includes a divided pixel 401 arranged for each pixel and a pixel common unit 408 arranged for every two divided pixels. The divided pixel 401 includes a photodiode 402 that is a photoelectric conversion element, and a transfer switch 403 that transfers charges generated by photoelectric conversion of the photodiode 402 by a pulse PTX.

  The pixel common unit 408 applies the level of the potential SVDD to the floating diffusion layer FD407 that accumulates the charges transferred by the transfer switches 403 of each divided pixel 401 and the floating diffusion layer FD407 connected to the gate of the pixel amplifier 406 by the reset pulse PRES. A reset switch 404 for resetting the pixel, a pixel amplifier 406 for amplifying the charge accumulated in the floating diffusion layer FD407 as a source follower, and a row selection switch 405 for selecting a row pixel selected by a vertical scanning circuit (not shown) by a selection pulse PSEL. Have.

  Note that in the pixel portion of the imaging element shown in FIG. 5, the charges photoelectrically converted by the photodiodes 402a and 402b are both transferred to the floating diffusion layer FD407 by controlling the transfer switches 403a and 403b. It is configured.

  The charge of the row pixel selected by the row selection switch 405 is output to the load current source 421 by the source follower to the vertical output line 422, and is stored in the transfer capacitor CTS427 by turning on the transfer gate 425 by the signal output pulse PTS. The transfer gate 424 is turned on by the pulse PTN and stored in the transfer capacitor CTN 426.

  Subsequently, the noise component is stored in the capacitor CHN 430 and the signal component is stored in the capacitor CHS 431 via the transfer switches 428 and 429 by the control signals PHS and PHN from the horizontal scanning circuit (not shown), and the difference between the two is stored in the pixel by the differential amplifier 432. Output as a signal.

  FIG. 6 shows the first drive timing in this embodiment.

  In FIG. 6, the first drive timing is a drive timing for independently reading out the output signals of the divided pixels shown in FIG. When signal reading is performed at the first drive timing, the output signal can be processed and used as a focus detection signal or a stereoscopic image generation signal in the digital signal processing circuit 113.

  In the first drive, the divided pixels a and b are read in this order.

  First, the signal of the unit pixel 901a is read during the period HBLKa + HSRA. As the signal HD indicating the start of one horizontal scanning period falls, the vertical output line 422 is reset to a constant potential by a circuit (not shown). Thereafter, the MOS transistor 404a is turned on by the PRES signal, so that the charge accumulated in the floating capacitor 407 provided at the gate of the MOS transistor 406a during the period T1a is reset to the constant potential SVDD.

  Subsequently, after the PRES signal is set to high level and the MOS transistor 406 is turned off, the PSEL signal is set to high level. As a result, the source follower circuit composed of the MOS transistor 405 and the load current source 421 is activated, and a noise output corresponding to the floating gate reset potential of the MOS transistor 406 is made on the vertical output line 422. By setting the PTN signal to the high level during the period when the PSEL is at the high level, the storage capacitor CTN424 for storing the noise component is connected to the vertical output line 422, and the storage capacitor CTN424 holds the signal of the noise component. .

  What is subsequently performed is accumulation of a mixed signal of photoelectric charges and noise components generated in the photoelectric conversion element. First, the vertical output line 422 is reset to a constant potential by a circuit (not shown). Thereafter, the PTXa signal is set to the high level, and the photocharge accumulated in the photoelectric conversion element 402a is transferred to the floating gate of the MOS transistor 406 by turning on the transfer MOS transistor 403a during the period T3a. At this time, since the PSEL signal remains at the high level, the source follower circuit is in an operating state, and the output of “light signal + noise signal” corresponding to the potential of the floating gate of the MOS transistor 406 is output on the vertical output line 422. Made. During a period T4a including the period T3a, the PTS signal is set to a high level this time. As a result, the storage capacitor CTS 427 for storing “photo charge component + noise component” is connected to the vertical output line 422, and the storage capacitor CTS 427 holds a signal of photo charge component + noise component.

  As described above, the noise component for one row and the optical signal + noise component generated by the photodiode are accumulated in CTN 426 and CTS 427, respectively.

  Next, during the period of HSRa, these two signals are transferred to the capacitors CHN430 and CHS431 by control pulses PHS and PHN controlled by a horizontal shift register (not shown), respectively. The noise component and the optical signal + noise component accumulated in the capacitors CHN 430 and CHS 431 are output by the differential amplifier 432 as (optical signal + noise component) −noise component, that is, an optical signal.

  Subsequently, during the period of HBLKb + HSRb, the control signals PTXb, PRES, and PSEL are controlled to read out the signal of the divided pixel 401b. Since the signal readout timing of the divided pixel 401b is the same as the signal readout timing of the divided pixel 401a described above, description thereof is omitted.

  By performing the reading operation as described above, signal reading of the two divided pixels 401a and 401b is completed.

  FIG. 7 shows the second drive timing of this embodiment.

  In FIG. 7, the second drive timing is a drive timing for collectively reading output signals of the divided pixels shown in FIG. 2. When the signal is read at the second drive timing, it is possible to read out at a high speed when the output signal of each divided pixel is unnecessary, such as during normal imaging.

  In the second drive timing, the first component described with reference to FIG. 6 is used until the PTN signal is set to the high level during the period in which the PSEL signal is at the high level so that the storage capacitor CTN 424 holds the noise component signal. This is the same as the drive timing.

  What is subsequently performed is accumulation of a mixed signal of photoelectric charges and noise components generated in the photoelectric conversion element. First, the vertical output line 422 is reset to a constant potential by a circuit (not shown). After that, the PTXa and PTXb signals are simultaneously set to the high level, and the photoelectric charges accumulated in the photoelectric conversion regions 402a and 402b are transferred to the floating gate of the MOS transistor 406 by turning on the transfer MOS transistor 403 during the period T3. At this time, since the PSEL signal remains at the high level, the source follower circuit is in an operating state, and the output of “light signal + noise signal” corresponding to the potential of the floating gate of the MOS transistor 406 is output on the vertical output line 422. Made.

  During a period T4 including this period T3, the PTS signal is set to a high level this time. As a result, the storage capacitor CTS 427 for storing “photo charge component + noise component” is connected to the vertical output line 422, and the storage capacitor CTS 427 holds a signal of photo charge component + noise component.

  As described above, the noise component for one row and the optical signal + noise component generated by the photodiode are accumulated in CTN 426 and CTS 427, respectively.

  Next, during the HSR period, these two signals are transferred to the capacitors CHN430 and CHS431 by control pulses PHS and PHN controlled by a horizontal shift register (not shown). The noise component and the optical signal + noise component accumulated in the capacitors CHN 430 and CHS 431 are output by the differential amplifier 432 as (optical signal + noise component) −noise component, that is, an optical signal.

  As described above, the imaging apparatus according to the present embodiment has been described with reference to FIGS. 1 to 7, but the present invention is not limited to this and can take various forms.

  For example, in the pixel configuration described in FIGS. 2 to 5, the divided pixels sharing the microlens are divided into two in order to easily understand the structure of the pixel. However, the present invention is not limited to this and is 2 × 2 It is good also as a structure which has divided pixels of 3 or more divisions, such as these 4 divisions.

  In addition, regarding the element cross-sectional structure of each pixel of the imaging element described with reference to FIG. Although described as a side close to 402, the present invention is not limited to this. In other words, if the curvature of the microlens 442 is configured so that the imaging plane α and the imaging plane β have a substantially imaging relationship with the pupil of the photographic lens, the positional relationship between the optical waveguide 445 and other components is Any mode may be used. For example, by changing the curvature of the micro lens 442 and forming an optical waveguide from the third electrode layer so that an image is formed in the third electrode layer, the photoelectric conversion layer does not have to be shifted downward. It becomes a good structure.

Claims (6)

In an imaging device having a photoelectric conversion unit divided into a plurality sharing a microlens,
An image pickup device, wherein an optical unit for guiding light incident on the microlens to each photoelectric conversion unit is provided on a light incident side of each photoelectric conversion unit.   The image pickup device according to claim 1, wherein the optical unit is an optical waveguide.   The imaging device according to claim 1, wherein the optical unit guides a light beam reaching a region between the photoelectric conversion units to any one of the photoelectric conversion units.   4. The image pickup device according to claim 1, wherein the optical unit is disposed in the vicinity of an imaging position of the microlens. 5.   4. The image pickup device according to claim 1, wherein the optical unit is disposed behind an imaging position of the microlens. 5. A taking lens,
An image pickup apparatus comprising: the image pickup device according to claim 1, which receives a light beam that has passed through the photographing lens.

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