JP5034185B2 - Imaging device and imaging apparatus - Google Patents

Description

  The present invention relates to an image pickup device including a light receiving element, and more particularly to an image pickup device in which a color filter is disposed on a light incident side of a light receiving element so that a color component to be observed can be observed.

  In recent years, two-dimensional image sensors are used in digital cameras and video cameras. Also, linear sensors (one-dimensional image sensors) are used in facsimiles and copiers.

  Such an image sensor (imaging element) includes a light receiving element (photoelectric conversion element), and detects incident light incident on the image sensor by the light receiving element. Incident light is detected after being converted into an electrical signal by the photoelectric conversion element.

  Note that a light receiving element such as a CMOS or CCD has high sensitivity even in a region outside the visible light wavelength region (for example, a wavelength region of 400 nm to 700 nm) which is a human visual sensitivity region. Moreover, it has a high sensitivity also about the wavelength range (henceforth "infrared region". For example, it is a wavelength range of 700 nm-1100 nm) on the wavelength side longer than a visible light wavelength range.

  The light receiving element receives incident light via the organic color filter. That is, on the light incident side of each light receiving element, organic color filters for the three primary colors of light are installed in order to extract a specific color component from the incident light and perform color separation. Incident light is color-separated by the organic color filter, and the color component to be observed is observed by the light receiving element.

  In addition, a light receiving element converts into an electrical signal according to the intensity of incident light. In other words, only the brightness of the incident light is detected, and the color of the incident light is not determined. Therefore, the light incident side of the light receiving element is provided with organic color filters of red (R), green (G), and blue (B), which are the three primary colors of light, so that the light from the subject is color-separated and specified. Taking out the light.

  Specifically, light that has passed through each color filter of red, green, and blue is incident on a light receiving element that faces each color filter, and is converted into an electrical signal by each light receiving element. Then, an output value (usually a voltage value is output) obtained by photoelectric conversion is synthesized, and the photographing target is reproduced as a color image.

  By the way, when the transmittance of such a color filter is low, the amount of light reaching the light receiving element is reduced, and the image quality is deteriorated (dark image). For example, FIG. 16 is a graph showing an example of the spectral transmittance of the color filter in the three primary colors of red, green, and blue light, but the vertex of the transmittance of green and blue is only about 80%.

  In recent years, the demand for increasing the number of pixels in an image sensor has increased, and the pixels have been miniaturized. Specifically, the pixel pitch (distance between pixels) is below 3 μm and is becoming around 2 μm. As described above, when the pixel pitch is a fine pixel in the vicinity of 2 μm, the area per pixel is reduced, so that the amount of light incident on the light receiving element is reduced. For this reason, the low transmittance of the color filter means a decrease in sensitivity of the light receiving element, which causes a decrease in image quality (a dark image).

  In addition, as shown in FIG. 17, the SPD sensitivity of the light receiving element shows a high value in the wavelength region near 700 nm, but decreases as the wavelength becomes shorter. In particular, in the vicinity of the blue wavelength range (400 nm to 500 nm), the sensitivity is about half that of red.

Further, as shown in FIG. 16, the transmittance of the blue color filter is lower than the transmittance of the red or green color filter.

  In view of the above, in an image sensor having three primary color filters of red, green, and blue, the sensitivity of the light receiving element is low in the blue wavelength region, and the blue color is higher than the transmittance of the red and green color filters. It can be seen that the transmittance of the filter is lower.

  For this reason, in the conventional imaging device, the sensitivity of blue is lower than that of red or green, and it is difficult to accurately reproduce the color balance.

  In this regard, a technique using a complementary color filter composed of yellow (Y), magenta (M), and cyan (C) has been proposed in order to cope with a decrease in the amount of light to the light receiving element (for example, Patent Documents). 1).

  In this technique, the combined light of red and green can be extracted by using a yellow (Y) color filter. Further, by using a magenta (M) color filter, it is possible to extract combined light of red and blue. Further, by using a cyan (C) color filter, the combined light of green and blue can be extracted.

In other words, since the complementary color filter transmits light of two colors, the transmittance can be increased, and a decrease in the amount of incident light can be suppressed.
JP 2002-5350 A

  However, in order to extract light of the three primary colors of red, green, and blue from the light that has passed through the color filters of the complementary colors of yellow, magenta, and cyan, for example, blue = (cyan + magenta-yellow) / 2, green = (cyan + Yellow-Magenta) / 2, Red = (Magenta + Yellow-Cyan) / 2, etc. The three primary colors of red, green, and blue from each value observed by the light receiving element through a complementary color filter It is necessary to perform a complicated calculation for calculating a value corresponding to.

  Therefore, it may be difficult to express a vivid color close to the primary color.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide an imaging device with good color balance and color reproducibility.

  In order to achieve the above object, the present invention takes the following measures.

The invention corresponding to claim 1 is an imaging device comprising a filter used for extracting a specific color component of incident light and a light receiving element for observing the incident light via the filter, wherein the filter is transparent comprising a filter, and a yellow filter used for extraction of the yellow component, seen including a red filter used in the extraction of the red component, the transparent flattening layer covering said red filter and the yellow filter, the transparent filter Is an image sensor formed by the transparent planarization layer .

According to a second aspect of the present invention, the image pickup device further includes a microlens for condensing light on the light receiving device, and the microlens is an image pickup device formed by the transparent flattening layer .

The invention corresponding to claim 3 is an imaging device comprising a filter used for extracting a specific color component of incident light and a light receiving element for observing the incident light via the filter, wherein the filter is transparent A filter, a yellow filter used to extract a yellow component, and a red filter used to extract a red component, and the number of pixels of the yellow filter is equal to the total number of pixels of the transparent filter and the red filter It is an image sensor.

According to a fourth aspect of the present invention, the light receiving element includes an incident light receiving element that observes the incident light via the transparent filter, a yellow light receiving element that observes the incident light via the yellow filter, and the incident light. A red light receiving element that observes the red light through the red filter, and an observation means that subtracts the observation result observed by the yellow light receiving element from the observation result observed by the incident light receiving element, and obtains a blue observation result; The imaging device further includes a calculation unit that subtracts the observation result observed with the red light receiving element from the observation result observed with the yellow light receiving element to obtain a green observation result .

  The invention corresponding to claim 5 is an image pickup device in which the transparent filter, the yellow filter, and the red filter are arranged adjacent to each other in a grid pattern to form a surface and form a unit of color separation. .

According to a sixth aspect of the present invention, the transparent filter is an image sensor that absorbs ultraviolet rays in a wavelength region shorter than 400 nm.

The invention corresponding to claim 7 is an image sensor further comprising a light shielding film for suppressing reflection and transmission of light other than light incident on the light receiving element of the incident light.

The invention corresponding to claim 8 includes a substrate on which the light receiving element is disposed, and the light shielding film is on the incident light incident side of the substrate, excluding a region where the incident light is incident on the light receiving element. It is an image sensor provided in another region.

The invention corresponding to claim 9 is an image pickup device in which the light-shielding film is provided with an ultraviolet absorbing function or an ultraviolet absorbing film is laminated.

The invention corresponding to claim 10 is an image pickup device in which the light-shielding film has a near-infrared absorbing function or is laminated with a film that absorbs near-infrared rays.

According to an eleventh aspect of the present invention, there is provided an image pickup device for detecting an intensity value of light existing in a specific wavelength region of incident light, and an arithmetic means for reproducing the incident light based on the light intensity value detected by the image pickup device. The imaging device includes: a semiconductor substrate; a photoelectric conversion element formed on the semiconductor substrate for receiving incident light; and formed on the photoelectric conversion element. A transparent filter that transmits incident light; a red filter that is formed on the photoelectric conversion element and is used to extract a red component of the incident light; and a yellow filter that is formed on the photoelectric conversion element and that is formed on the photoelectric conversion element. A yellow filter used for extraction; a transparent flattening layer formed so as to cover the yellow filter and the red filter; and a microlens formed above the yellow filter and the red filter. The calculation means calculates the value of the blue component of the incident light by subtracting the intensity value of the incident light received via the yellow filter from the intensity value of the incident light received via the transparent filter. Means for subtracting the intensity value of the incident light received via the red filter from the intensity value of the incident light received via the yellow filter, and calculating the value of the green component of the incident light; And means for calculating the value of the red component of the incident light based on the intensity value of the incident light received via the red filter, wherein the transparent filter is an imaging device formed by the transparent flattening layer. .

The invention corresponding to claim 12 is the imaging device in which the microlens is formed by the transparent planarization layer.

According to a thirteenth aspect of the present invention, there is provided an image pickup device for detecting an intensity value of light existing in a specific wavelength region of incident light, and an arithmetic means for reproducing the incident light based on the light intensity value detected by the image pickup device. The imaging device includes: a semiconductor substrate; a photoelectric conversion element formed on the semiconductor substrate for receiving incident light; and formed on the photoelectric conversion element. A transparent filter that transmits incident light; a red filter that is formed on the photoelectric conversion element and is used to extract a red component of the incident light; and a yellow filter that is formed on the photoelectric conversion element and that is formed on the photoelectric conversion element. comprising a yellow filter used for extraction, and the yellow filter and the red filter and the transparent flattening layer formed so as to cover the, and a micro lens formed above said red filter and the yellow filter Said calculating means, from the intensity values of the incident light received through the transparent filter, through the yellow filter by subtracting processes the intensity values of the incident light received, calculates the value of the blue component of the incident light Means for subtracting the intensity value of the incident light received via the red filter from the intensity value of the incident light received via the yellow filter, and calculating the value of the green component of the incident light; Means for calculating the value of the red component of the incident light based on the intensity value of the incident light received via the red filter, the number of pixels of the yellow filter, and the total of the transparent filter and the red filter Imaging device with the same number of pixels .

<Action>
Accordingly, invention corresponding to claim 1 includes a transparent filter, a yellow filter used for extraction of the yellow component, seen including a red filter used in the extraction of the red component, a transparent covering the yellow filter and the red filter Since it is an image sensor that has a flattening layer and the transparent filter is formed by the transparent flattening layer , it can express vivid colors close to the primary color without complicated calculations, and color balance and color reproducibility. is rather good, further, it is unnecessary to provide a pattern forming step of the transparent filter can provide an imaging device capable of simplifying the manufacturing process.

The invention corresponding to claim 2 further includes a microlens for condensing incident light on the light receiving element in addition to the operation corresponding to claim 1, and the microlens is formed of a transparent flattening layer. The imaging element can be made thin.

The invention corresponding to claim 3 includes a transparent filter, a yellow filter used for extracting a yellow component, and a red filter used for extracting a red component, the number of pixels of the yellow filter, the transparent filter, and the red filter Since the image sensors have the same total number of pixels, it is possible to express vivid colors close to the primary color without complicated calculations, good color balance and color reproducibility, and green for each unit. It is possible to provide an image sensor that can individually calculate the color components of blue.

In addition to the actions corresponding to claims 1 to 3 , the invention corresponding to claim 4 subtracts the observation result observed with the yellow light receiving element from the observation result observed with the incident light receiving element to obtain the blue observation result. Compared to the complementary color filter, it has a calculation means to calculate and a calculation means to obtain the green observation result by subtracting the observation result observed by the red light receiving element from the observation result observed by the yellow light receiving element. Thus, it is possible to provide an image pickup device that can express a vivid color close to the primary color without complicated calculations and has good color balance and color reproducibility.

  In addition to the actions corresponding to the first to fourth aspects, the invention corresponding to the fifth aspect forms a unit by separating the transparent filter, the yellow filter, and the red filter adjacently in a grid pattern to form a unit of color separation. Therefore, the color components of green and blue can be calculated for each unit.

In the invention corresponding to claim 6 , in addition to the actions corresponding to claims 1 to 5 , since the transparent filter absorbs ultraviolet rays in a wavelength region shorter than 400 nm, it is possible to suppress the influence of ultraviolet rays not recognized by humans.

The invention corresponding to claims 7 and 8 includes the light shielding film for suppressing reflection of other light except the light incident on the light receiving element, in addition to the actions corresponding to claims 1 to 6 . The influence of stray light can be suppressed.

In the invention corresponding to claim 9 , in addition to the actions corresponding to claims 7 and 8 , the light-shielding film is provided with an ultraviolet absorbing function or laminated with an ultraviolet absorbing film. The influence can be suppressed.

In the invention corresponding to claim 10 , in addition to the actions corresponding to claims 7-9 , since the light shielding film has a near infrared ray absorbing function or a film absorbing near infrared rays is laminated, human beings do not recognize it. The influence of infrared rays can be suppressed.

The invention corresponding to claim 11 includes a transparent flattening layer that includes a transparent filter, a yellow filter, and a red filter, and covers the yellow filter and the red filter, and the transparent filter is formed by the transparent flattening layer. Complicated with an element and means for calculating the value of the blue component of the incident light, means for calculating the value of the green component of the incident light, and means for calculating the value of the red component of the incident light It is possible to express a vivid color close to the primary color without performing a complicated calculation, and it has a good color balance and color reproducibility. Furthermore, it is not necessary to provide a pattern forming step for the transparent filter, and the manufacturing process can be simplified. An imaging device can be provided.

In the invention corresponding to claim 12 , in addition to the action corresponding to claim 11 , since the microlens is formed of the transparent flattening layer, the imaging device can be made thin.

Invention, have a transparent filter, yellow filter red filter, comprising a transparent flattening layer covering the yellow filter and a red filter, the number of pixels of the yellow filter, transparent filter and red corresponding to claim 13 An image sensor that equalizes the total number of pixels of the filter, means for calculating the value of the blue component of the incident light, means for calculating the value of the green component of the incident light, means for calculating the value of the red component of the incident light since an arithmetic unit having, complicated calculations can express bright colors close to the colors without having, rather good and the color balance and color reproduction, further, the green and blue for each one unit An imaging device capable of individually calculating color components can be provided.

  According to the present invention, it is possible to provide an image sensor with good color balance and color reproducibility. In particular, it is possible to suppress a decrease in blue sensitivity and improve the color balance.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following description, the same elements are denoted by the same reference numerals and description thereof is omitted.

<First Embodiment>
In the present embodiment, an image sensor that includes a light receiving element such as a CMOS or a CCD, and that provides a filter layer on the light incident side of the light receiving element to observe a color component to be observed will be described.

  FIG. 1 is a plan view illustrating an example of an arrangement state of filters in the image sensor according to the present embodiment. FIG. 1 shows an example of the state of the filter viewed from the light incident side.

  FIG. 2 is a cross-sectional view showing an example of an image sensor according to the present embodiment. FIG. 2 shows a cross section taken along the line I-I ′ of FIG. 1. Although FIG. 2 shows an example in which the light receiving element is a CMOS, the same applies to the case where the light receiving element is a CCD. Hereinafter, the same configuration applies to other cross-sectional views of the image sensor.

  The imaging device 1 according to the present embodiment includes a filter layer 2 that is used to extract a specific color component of incident light, light receiving elements 3W, 3Y, and 3R that observe the incident light via the filter layer 2, and a calculation unit 4. It comprises.

  The filter layer 2 includes a transparent filter 2W, a yellow filter 2Y, and a red filter 2R. A unit of color separation is formed by a total of four pixels, in which the yellow filter 2Y has two pixels and the transparent filter 2W and the red filter 2R each have one pixel. That is, the ratio of the number of pixels of the yellow filter 2Y is made equal to the ratio of the total number of pixels of the transparent filter 2W and the red filter 2R. Thereby, the arithmetic processing of (white)-(yellow) and (yellow)-(red), which will be described later, can be executed for each unit.

  The transparent filter 2W, yellow filter 2Y, and red filter 2R are adjacently arranged in a grid pattern to form a surface. Thereby, the transparent filter 2W, the yellow filter 2Y, and the red filter 2R are appropriately arranged.

  The transparent filter 2W is preferably transmitted without absorbing light having a long wavelength of 400 nm or longer. For example, the transparent filter 2W is preferably a filter having a transmittance of 95% or more for light having a wavelength of 400 nm or more with reference to transparent glass having a refractive index n of about 1.5. Such a transparent filter 2W is formed of a phenol-based, polystyrene-based, acrylic-based resin or the like, but is preferably formed of a polystyrene-based resin, preferably an acrylic-based resin, from the viewpoint of heat resistance.

  The yellow filter 2Y is a filter used for extracting a yellow component (light obtained by combining a red component and a green component) from incident light. The yellow filter 2Y is a complementary color filter. In general, a complementary color filter has a higher light transmittance than a color filter of three primary colors of red, green, and blue.

  The red filter 2R is a red color filter used for extracting a red component of incident light. In general, the red color filter has higher transmittance than the blue color filter and the green color filter, which are other color filters of the three primary colors.

  The incident light receiving element 3 </ b> W, the yellow light receiving element 3 </ b> Y, and the red light receiving element 3 </ b> R that are light receiving elements are arranged on the opposite side of the filter layer 2 from the light incident side. Then, the light passing through the color filter is received, and the received light is converted into an electric signal to obtain an observation data value. A one-to-one combination of a light receiving element and a filter corresponds to a pixel.

  The incident light receiving element 3W is associated with the transparent filter 2W, and observes incident light via the transparent filter 2W.

  The yellow light receiving element 3Y is associated with the yellow filter 2Y and observes incident light via the yellow filter 2Y.

  The red light receiving element 3R is associated with the red filter 2R and observes incident light via the red filter 2R.

  The computing unit 4 includes a blue computing unit 4B, a green computing unit 4G, and a red computing unit 4R. The calculation unit 4 has a function of obtaining a blue observation data value Db and a green observation data value Dg based on the observation data values Dw and Dy by the incident light receiving element 3W and the yellow light receiving element 3Y.

  The blue calculation unit 4B subtracts the observation data value Dy observed by the yellow light receiving element 3Y from the observation data value Dw observed by the incident light receiving element 3W, and obtains the blue observation data value Db (= Dw−Dy). Ask.

  The green calculation unit 4G subtracts the observation data value Dr observed by the red light receiving element 3R from the observation data value Dy observed by the yellow light receiving element 3Y to obtain a green observation data value Dg (= Dy−Dr). .

  That is, if the colors corresponding to the transparent filter 2W, yellow filter 2Y, and red filter 2R are white (W), yellow (Y), and red (R), respectively, the following expressions (1) to (2) are satisfied. Based on this, data values of blue (B) and green (G) can be obtained.

Blue (B) = White (W) -Yellow (Y) (1)
Green (G) = Yellow (Y) -Red (R) (2)
FIG. 2 shows a cross section that crosses the yellow filter 2Y and the transparent filter 2W and also crosses the yellow light receiving element 3Y and the transparent light receiving element 3W, but crosses the other filters and other light receiving elements. The same structure is applied to the cross section.

  On the light incident side of the semiconductor substrate 5, an incident light receiving element 3W, a yellow light receiving element 3Y, and a red light receiving element 3R are formed and disposed.

  A planarizing layer 6 is laminated on the light incident side surface of the semiconductor substrate 5 on which the incident light receiving element 3W, the yellow light receiving element 3Y, and the red light receiving element 3R are formed. Thereby, the transparent filter 2W, the yellow filter 2Y, and the red filter 2R can be formed on a flat installation surface. Note that the planarization layer 6 may be omitted in order to make the imaging device 1 thin. As the material of the planarizing layer 6, a resin containing one or a plurality of resins such as acrylic, epoxy, polyimide, urethane, melamine, polyester, urea, and styrene can be used. .

  On the light incident side of the flattening layer 6, transparent filters 2W, yellow filters 2Y, and red filters 2R respectively corresponding to the incident light receiving element 3W, yellow light receiving element 3Y, and red light receiving element 3R are arranged to form the filter layer 2. Is done. A resin layer (transparent flattening layer) 7 is laminated on the light incident side of the filter layer 2.

  On the light incident side of the resin layer 7, microlenses 8 corresponding to the incident light receiving element 3W, the yellow light receiving element 3Y, and the red light receiving element 3R are provided.

  The microlens 8 is disposed above each transparent filter 2W, yellow filter 2Y, and red filter 2R so as to make a pair with each transparent filter 2W, yellow filter 2Y, and red filter 2R. The microlens 8 is formed of acrylic resin or the like, and improves the light condensing property to the elbow light receiving element 3W, the yellow light receiving element 3Y and the red light receiving element 3R.

  In this embodiment, the film thickness of each filter is 1.4 μm, and the pixel pitch (the pitch of the transparent filter 2W, yellow filter 2Y, and red filter 2R) is 2.6 μm. The planarizing layer 6 is formed of a thermosetting acrylic resin to which an ultraviolet absorber is added, and has a thickness of 0.3 μm.

  Here, the UV absorber is added to the flattening layer 6 by a known photolithography method in which pattern exposure or development is performed on the photosensitive resin layer to leave the photosensitive resin in a predetermined portion. This is because, when forming a color filter, a good-shaped filter is formed by preventing halation of exposure light from the semiconductor substrate 5 as a base.

  In the present embodiment, the planarization layer 6 is formed. However, the planarization layer 6 may be omitted for the purpose of further thinning the imaging device.

  In this embodiment, the transparent filter 2W is formed to a thickness of about 1 μm using an alkali-soluble photosensitive acrylic resin (refractive index n = 1.55).

  The yellow filter 2Y and the red filter 2R are formed using a colored photosensitive resin solution in which a color material (pigment / pigment) is attached to a transparent resin. Note that the transparent filter 2W may be formed of a transparent resin to which no coloring matter is added.

  In this embodiment, the yellow filter 2Y and the red filter 2R, which are color filters, are colored photosensitive materials obtained by adding and dispersing a predetermined organic pigment to the transparent resin (photosensitive acrylic resin) used for forming the transparent filter 2W. It is made of a functional resin. For example, C.I. Pigment Yellow 150 is an example of the organic pigment used for forming the yellow filter 2Y. Alternatively, a mixed pigment of C.I. Pigment Yellow 150 and C.I. Pigment Yellow 139 may be used. Moreover, as an organic pigment used for formation of the red filter 2R, mixing of C.I. Pigment Red177, C.I. Pigment Red48: 1, and C.I. Pigment Yellow139 is mentioned.

  FIG. 3 is a graph showing an example of the spectral transmittance for the transparent filter 2W, the yellow filter 2Y, and the red filter 2R.

  The image sensor 1 performs an operation (subtraction) based on the observation data values Dw, Dy, and Dr by the respective light receiving elements, and obtains observation data values Db, Dg, and Dr of the three primary colors of red, green, and blue. That is, it can be considered that the imaging device 1 includes a blue filter and a green filter in appearance (virtually) by performing such a calculation.

  FIG. 4 is a graph showing an example of the spectral transmittance of the apparent blue filter, green filter, and red filter obtained by the calculation of the image sensor 1. When the spectral transmittance of the apparent blue filter and green filter of the image sensor 1 shown in FIG. 4 is compared with the spectral transmittance of the conventional blue color filter and green color filter shown in FIG. The spectral transmittance of the apparent blue filter and green filter of the element 1 has the following characteristics.

  That is, the apparent transmittances of the blue filter and the green filter of the image sensor 1 are characterized in that the transmittance is higher than the conventional blue color filter and green color filter in the wavelength range of each color.

  In particular, the apparent blue filter has a higher transmittance in the blue wavelength region than the conventional blue color filter.

  For this reason, in the imaging device 1, the sensitivity of blue is improved and the color balance is improved.

  Hereinafter, the imaging device 1 according to the present embodiment and a conventional imaging device will be described in comparison.

  First, the “apparent color filter” will be described.

  FIG. 5 is a graph showing an example of actual spectral characteristics of a conventional image sensor.

  The spectral characteristics of the conventional image sensor are obtained by multiplying the sensitivity of the light receiving element (FIG. 5A) and the transmittance of the filter disposed on the light incident side of the light receiving element (FIG. 5B). It is considered equivalent to the product value, and is expressed as shown in FIG.

  As shown in FIG. 5B, the blue color filter in the conventional image sensor has a lower transmittance than the other red and green color filters. Further, as shown in FIG. 5A, the sensitivity of the light receiving element in the blue wavelength region is lower than the sensitivity in the other red and green wavelength regions. For this reason, in the conventional image sensor, when the sensitivity ratio is obtained, blue / green is too smaller than red / green. That is, there is a problem that color reproducibility is low.

  On the other hand, the image sensor 1 in the present embodiment includes a transparent filter 2W, a yellow filter 2Y, and a red filter 2R instead of the three primary colors of red, green, and blue color filters.

  Therefore, the spectral characteristics of the image sensor 1 in the present embodiment are multiplied by the sensitivity of the light receiving element and the transmittances of the transparent filter 2W, yellow filter 2Y, and red filter 2R disposed on the light incident side of the light receiving element. It is considered equivalent to the combined product value.

  The transmittances of the transparent filter 2W, the yellow filter 2Y, and the red filter 2R are higher than those of the blue color filter and the green color filter.

  Therefore, when the incident light receiving element 3W, the yellow light receiving element 3Y, and the red light receiving element 3R are observed via the transparent filter 2W, the yellow filter 2Y, and the red filter 2R, the calculation is performed based on the observed data values Dw, Dy, and Dr. The observed data values Db and Dg thus obtained can be said to be observation results obtained with high transmittance.

  In particular, the blue observation data value Db is equivalent to that observed at a high light intensity, the blue / green sensitivity ratio can be increased, and the color reproducibility can be improved.

  Further, in the present embodiment, the blue observation data value Db and the green observation data value Dg can be obtained by performing a simple calculation called subtraction once.

  Therefore, the calculation can be simplified as compared with an image pickup device using a conventional complementary color filter, and a vivid color close to the primary color can be expressed.

  Next, “noise due to dark current” will be described.

  As shown in FIG. 5C, the light receiving element generates a slight current even when light is not incident. The current that flows from the light receiving element even though such light is not incident is called a dark current and causes noise. Since the conventional color filters of the three primary colors of red, green, and blue transmit light in a predetermined wavelength region in terms of spectral characteristics, there are also wavelength regions that block light.

  However, the light receiving element generates dark current even in a wavelength region where light is blocked. For this reason, the observation result of the conventional image sensor includes noise due to dark current in addition to the observation result of light in the wavelength range where light is transmitted, and this noise may reduce the color reproducibility. .

  On the other hand, as described above, the imaging element 1 according to the present embodiment uses the observation data value Dw of the incident light receiving element 3W and the observation data value Dy of the yellow light receiving element 3Y to observe data of the yellow light receiving element 3Y. Since the value Dy and the observation data value Dr of the red light receiving element 3R are subtracted, the dark current value is canceled. Thereby, noise can be removed from the observation result, so that color reproducibility can be improved.

  Next, “spectral float” will be described.

  As shown in FIG. 5B, in the spectral transmittance of the conventional red, green, and blue color filters, the transmittance at the bottom of the spectral curve of the red and blue color filters is as low as several percent. The transmittance at the bottom of the spectral curve of the color filter is as high as about 10%. Thus, it is said that the float of a spectrum is large that the transmittance | permeability of a skirt part is high.

  In the conventional imaging device, the base of the spectral curve of the green color filter exists in the red and blue wavelength regions, and the spectrum of the green base is large. For this reason, red and blue are mixed with the observation result of green, and there is a problem that the reproducibility of green deteriorates.

  On the other hand, in the imaging device 1 according to the present embodiment, as described above, the observation data of the yellow light receiving element 3Y is calculated from the observation data value Dw of the incident light receiving element 3W and the observation data value Dy of the yellow light receiving element 3Y. The value Dy and the observation data value Dr of the red light receiving element 3R are subtracted. Therefore, the float of the spectrum can be reduced and the color reproducibility can be improved.

  Next, the “ultraviolet absorber and infrared absorber” will be described.

  A light receiving element such as a CMOS or CCD has a slight sensitivity even in an ultraviolet region that is not felt by humans.

  Therefore, it is desirable that the transparent filter 2W according to the present embodiment does not transmit light of 400 nm or less and allows light having a wavelength of 400 nm or less to pass through without being absorbed. Therefore, an ultraviolet absorber or a photoinitiator or curing agent used for curing the resin may be attached to the transparent filter 2W according to this embodiment, and an ultraviolet absorbing function may be added to the transparent filter 2W.

  As the ultraviolet absorber, for example, benzotriazole compounds, benzophenone compounds, salicylic acid chemicals, and coumarin compounds can be used. Further, for example, a light stabilizer such as a hindered compound or a quencher may be added to the ultraviolet absorber.

  Furthermore, the polymer, monomer, or curing agent of the resin used for forming the transparent filter 2W may be pendant with a functional group having an ultraviolet absorption function, or may be polymerized with a group that can be incorporated into the polymer. For example, quinones or anthracene may be introduced into the polymer, or a monomer having an ultraviolet absorbing group may be added. The pendant refers to incorporation into a resin molecular chain in the form of a reactive absorbent or the like.

  Moreover, you may add an infrared absorptive compound and an infrared absorber to resin which comprises the transparent filter 2W. Specifically, it can be added to the resin constituting the transparent filter 2W by a pendant method.

  Further, according to the present embodiment, the filter layer 2 has one unit of color separation by a total of four pixels, in which the yellow filter 2Y has two pixels and the transparent filter 2W and the red filter 2R each have one pixel. For this reason, when obtaining blue and green data values, it is not necessary to use yellow data values in duplicate. That is, the calculation processing of (white)-(yellow) and (yellow)-(red) can be executed individually within one unit, and the calculation processing can be speeded up.

  In the image pickup device 1 according to the present embodiment described above, it is possible to obtain the same effect as when a high-transmitting green / blue filter is provided, and in particular, blue is observed more than the conventional image pickup device. Accuracy can be improved.

<Second Embodiment>
In the present embodiment, a modified example of the image sensor according to the first embodiment will be described. Note that the imaging element 9 according to the present embodiment is configured by integrating the transparent filter 2W and the resin layer 7 in the imaging element 1 according to the first embodiment.

  FIG. 6 is a cross-sectional view showing an example of an image sensor according to the present embodiment. FIG. 6 corresponds to the I-I ′ cross section of FIG. 1. The transparent filter 10W corresponds to the transparent filter 2W and the resin layer 7 of the first embodiment.

  In the image sensor 9 according to this embodiment, a part of the transparent filter 10W is placed at the position of the transparent filter 2W according to the first embodiment.

  The other part of the transparent filter 10W covers the surface on the light incident side of the yellow filter 2Y or the red filter 2R. That is, the transparent filter 10W has a configuration in which the transparent filter 2W according to the first embodiment and the resin layer 7 are integrated, and also serves as a transparent flattening layer.

  The image sensor 9 includes a transparent filter 10W, a yellow filter 2Y, and a red filter 2R.

  The incident light receiving element 3W, the yellow light receiving element 3Y, and the red light receiving element 3R receive the light that has passed through the transparent filter 10W, the yellow filter 2Y, and the red filter 2R, respectively, and convert them into electrical signals.

  Similar to the first embodiment, the image sensor 9 performs an operation (subtraction) based on the observation data values Dw, Dy, and Dr by the respective light receiving elements, and the observation data values Db of the three primary colors of red, green, and blue. And get Dg. In other words, the imaging device 9 is apparently (virtually) provided with a blue filter, a green filter, and a red filter by performing a calculation (subtraction) based on the observation data value by each light receiving element. Can think.

  An example of the apparent blue and green filters obtained by the calculation of the image sensor 9 and the spectral transmittance of wavelengths from 400 nm to 800 nm for the red filter is the same as in FIG.

  The apparent transmittance of the blue filter and the green filter of the image pickup device 9 is characterized in that the transmittance is higher than that of the conventional blue color filter and green color filter in the wavelength range of each color.

  In the present embodiment described above, after forming the yellow filter 2Y and the red filter 2R, the transparent filter 10W that is a transparent flattening layer is formed so as to cover each filter. Thus, the light incident side surfaces of the yellow filter 2Y and the red filter 2R are covered with the transparent filter 10W, and the transparent filter 10W and the transparent flattening layer are integrated.

  That is, since the transparent filter 10W and the transparent flattening layer forming process are integrated, there is no need to provide a transparent filter pattern forming process in the formation of the filter, and the manufacturing process of the image sensor 9 is simplified. Can be made.

  Specifically, a part of the transparent filter 10W, which is a transparent flattening layer, is disposed in a portion where the transparent filter 2W is formed in the first embodiment, so that the transparent filter 10W serves as a transparent flattening layer. Fulfill. Therefore, the process of forming a transparent filter uniquely by a technique such as photolithography can be omitted. That is, a filter for three colors can be configured with the effort of forming the filters for two colors (yellow and red), and the filter forming process can be reduced to one color.

<Third Embodiment>
In the present embodiment, modifications of the image sensor according to the first and second embodiments will be described. The image sensor 11 according to the present embodiment has a transparent filter 10 </ b> W and a microlens 8 integrally formed in the image sensor 9 according to the second embodiment.

  FIG. 7 is a cross-sectional view showing an example of an image sensor according to the present embodiment.

  The image sensor 11 according to the present embodiment includes a transparent filter 12W in which the microlens 8 of the image sensor 9 according to the second embodiment and the transparent filter 10W are integrated. That is, the transparent filter 12W also has a function of improving the light condensing property to the incident light receiving element 3W, the yellow light receiving element 3Y, and the red light receiving element 3R.

  Below, the manufacturing process of this image pick-up element 11 is demonstrated using FIGS. 8-12.

  First, the planarizing layer 6 made of a transparent resin is formed on the semiconductor substrate 5 on which the incident light receiving element 3W, the yellow light receiving element 3Y, and the red light receiving element 3R are formed (FIG. 8). Specifically, a coating solution containing acrylic resin as a main component is spin-coated at a rotational speed of 2000 rpm on the semiconductor substrate 5 on which the light receiving elements are two-dimensionally arranged. Then, a planarization layer 6 having a thickness of 0.2 μm is formed by performing a heat treatment at 200 ° C. to form a hard film. As the acrylic resin coating solution, a coating solution to which a coumarin-based ultraviolet absorber having a solid ratio of about 3% is added can be used.

  In forming a color filter made of a photosensitive resin, since ultraviolet rays are used for pattern exposure to the photosensitive resin, an ultraviolet absorber may be added to the planarizing layer 6 in order to prevent halation during pattern exposure. Good. Further, the planarization layer 6 may be omitted in order to make the imaging device 11 thin.

  Next, the yellow filter 2Y and the red filter 2R are formed by a photolithography technique (FIG. 9).

  Specifically, the yellow filter 2Y and the red filter 2R having a film thickness of about 1 μm are formed using two kinds of color resists (yellow and red) in which a color material is mixed with a photosensitive acrylic resin that can be exposed and developed. An organic pigment C.I. Pigment Yellow 150 can be used as the color material of the yellow filter 2Y. The yellow filter 2Y has a solid ratio of the color material (organic pigment) of about 33%. In addition, a mixed pigment of C.I. PigmentRed177, C.I. Pigment Red48: 1 and C.I. Pigment Yellow139 can be used for the color material of the red filter 2R. In the red filter 2R, the solid ratio of the color material (organic pigment) is about 48%.

  Next, a transparent resin layer is spin-coated on the semiconductor substrate 5 so as to cover the yellow filter 2Y and the red filter 2R. Then, the transparent resin layer is thermally cured at 180 ° C. for 3 minutes to form the planarization layer 12 including the transparent filter 12W (FIG. 10). The flattening layer 12 is made of substantially the same material as the flattening layer 6 and is formed of a thermosetting acrylic resin coating liquid having a high solid ratio for a thick film. The acrylic resin contains 2% of a coumarin ultraviolet absorber. The planarizing film 12 has a thickness of about 2 μm.

  Then, a photosensitive phenol resin layer 13 that can be exposed and developed is formed on the planarizing layer 12. The photosensitive phenol resin layer 13 is a resin having a “thermal reflow property” that is melted by heat treatment and rounded into a lens shape by surface tension.

  Next, the photosensitive phenol resin layer 13 is subjected to pattern exposure / development / hardening treatment, etc. to obtain a photosensitive phenol resin having a predetermined pattern.

  Next, 200 degreeC heat processing is performed and the photosensitive phenol resin 13 of a predetermined pattern is fluidized. As a result, a hemispherical lens matrix 13a having a thickness of about 0.6 μm is formed (FIG. 11).

  Next, anisotropic dry etching is performed using the lens matrix 13a as a mask to transfer the shape of the lens matrix 13a to the planarization layer 12 to form a microlens (FIG. 12). That is, the lens matrix 13a disappears by etching, but the lens matrix 13a serves as a mask for the transparent filter 12W, and the hemispherical shape of the lens matrix 13a is transferred to the transparent filter 12W. Thereby, the microlens 8 and the transparent filter 12W are formed simultaneously. The dry etching amount (etching depth) is about 1 μm. The yellow filter 2Y and the red filter 2R are effectively made to have a film thickness of 1.2 μm as the etching depth to the surface.

  As described above, it is possible to obtain the image sensor 11 in which a part of the transparent filter 12W functions as a microlens. In addition, since the transparent filter 12W and the microlens are integrated, the imaging element 11 can be thinned.

  In the present embodiment, the transparent filter 12W serving as a transparent flattening layer has a microlens shape, but the transparent filter 12W serving as a transparent flattening layer can be used without forming a microlens. Good. In this case, after forming the transparent filter 12W in the third step of FIG. 10, the imaging element can be obtained without performing the steps after the formation of the photosensitive phenol resin 13.

  Further, as described above, it is preferable to add an ultraviolet absorber to the planarizing layer 6 in order to prevent halation during pattern exposure of the photosensitive resin.

  Moreover, in order to prevent the generation | occurrence | production of the noise by the ultraviolet-ray based on a light receiving element having a sensitivity in an ultraviolet region, it is preferable to add an ultraviolet absorber to the transparent filter 12W.

  Examples of the ultraviolet absorber include fine particles made of a metal oxide such as cerium oxide or titanium oxide. However, as described above, when the lens shape is transferred to the transparent filter 12W, and the transparent filter 12W is a transfer type microlens, when an ultraviolet absorber is not added, an inorganic material is contained in the resin of the transfer lens. Becomes an optical foreign material. For this reason, the light may be blocked, and a black portion is generated in the image obtained by the image sensor 11.

  Therefore, it is preferable to use a dye-based ultraviolet absorber. For example, benzotriazole, benzophenone, triazine, salicylate, coumarin, xanthene, or methoxycinnamate organic compounds may be used as the ultraviolet absorber.

  In the above embodiments, yellow may be a common red color. That is, yellow is commonly included in the red portion except for the transparent portion, and may be used as an undercolor for other color portions except for the transparent portion. In this case, for example, the yellow filter 2Y is formed at the yellow formation position with the yellow resin, and at the same time, the yellow filter 2Y is formed at the red formation position, and then the red filter 2R is formed at the red formation position.

<Fourth embodiment>
In this embodiment, a reflection suppression filter that suppresses reflection, diffusion, and wraparound of light other than light incident on the light receiving element out of incident light is provided on the incident light incident side of the substrate and incident light on the light receiving element. An image sensor provided in other regions excluding the region where the light is incident will be described.

  FIG. 13 is a plan view showing a first example of the arrangement position of the light shielding film of the image sensor according to the present embodiment. The imaging element 17 shown in FIG. 13 is provided with a light-shielding film 19 that suppresses reflection and transmission of light on the outer periphery of the effective pixel part 18 on which the spectral filter is installed, on the light incident side of the light receiving element. The image sensor 17 has an electrode portion 20 made of aluminum or the like for electrical connection with the outside, and the light shielding film 19 is not formed on the electrode portion 20.

  The light shielding film 19 is formed, for example, by applying a resin liquid in which an organic pigment (mixture of C.I. Pigment violet 23 and C.I. Pigment Red 177, C.I. Pigment Red 48: 1, C.I. Pigment Yellow 139) is dispersed and mixed as a coloring material and hardening. However, the color material is not limited to this, and other pigments may be used. Further, it may be a single layer or a laminate of different colors. Arranging the light shielding film 19 on the outer peripheral portion of the effective pixel portion 18 of the image sensor 17 can prevent the observation result of the image sensor 17 from being affected by noise, and is effective in improving the image quality. .

  In the present embodiment, it is desirable that the light shielding film 19 has a function of cutting infrared light in addition to the function of cutting visible light. The infrared light cut function can be realized by forming the light shielding film 19 with a film thickness of 0.8 μm using, for example, a black pigment such as carbon black having a solid ratio of 40%.

  In the imaging element 17, a light shielding film 19 having transmission suppression characteristics in the visible light wavelength region is disposed on the semiconductor substrate 5 and outside the opening of the light receiving element.

  Supplementally, in a conventional image sensor, light incident on a portion other than the light receiving element may stray in the image sensor and become stray light. This stray light becomes noise when entering the light receiving element. Further, when unnecessary light is incident on the peripheral area of the light receiving element, it causes noise. However, in the present embodiment, the light shielding film 19 having a transmission suppressing characteristic in the visible light wavelength region is disposed around the effective opening of the light receiving element and a part of the semiconductor substrate 5 (for example, the outer periphery of the semiconductor substrate 5). Yes. Therefore, the light incident on the other portions except the light receiving element is absorbed by the light shielding film 19.

  Thereby, it is possible to prevent stray light and unnecessary light from entering the light receiving element. That is, noise can be reduced, and the image quality obtained by the image sensor 17 can be improved.

  When the light shielding film 19 using a black pigment such as carbon black has insufficient infrared and ultraviolet absorption performance, the light shielding film 19 is disposed on a portion of the semiconductor substrate 5 that is not an effective opening of the light receiving element. Further, a film 16 that absorbs infrared rays and ultraviolet rays may be laminated on the light shielding film 19. As a result, it is possible to prevent infrared rays and ultraviolet rays incident on a portion that is not a light receiving element from straying, becoming stray light, and generating noise. In addition, if the film | membrane 16 which absorbs infrared rays and an ultraviolet-ray uses the resin which added the infrared absorber and the ultraviolet absorber to the transparent resin used for formation of the micro lens 8, material cost can also be reduced.

  In the present embodiment, the case where the image sensor 1 according to the first embodiment includes the light shielding film 19 and the film 16 is described as an example. The light shielding film 19 and the film 16 may be provided. Further, only the light shielding film 19 may be provided for the image sensor. Further, an ultraviolet absorber or an infrared absorber may be added to the light shielding film 19.

<Fifth Embodiment>
The imaging device 1U in the present embodiment includes at least two or more filters, has transmission suppression characteristics for light on the shorter wavelength side than the first wavelength, and has transmission characteristics for light on the longer wavelength side than the first wavelength. A second filter having transmission suppression characteristics for light having a wavelength longer than the first wavelength and shorter than the second wavelength, and having transmission characteristics for light having a longer wavelength than the second wavelength; Is provided. Each filter according to the present embodiment has transmission suppression characteristics in a short wavelength region and transmission characteristics in a long wavelength region. In addition, it is desirable to have a substantially S-shaped transmittance curve in terms of spectral characteristics.

  Light incident through the first filter and the second filter is received by the first light receiving element and the second light receiving element, respectively, and converted into an electrical signal.

  Specifically, the imaging device 1U has a first wavelength region that exhibits a transmittance of 10% or less in a wavelength region of 350 nm to 750 nm, and is longer than the first wavelength region and is 450 nm to 1100 nm. The filter F1-the filter F7 which has a wavelength range which is the transmittance | permeability of 90% or more in a wavelength range are provided. Supplementally, the first filter and the second filter are names representing relative relationships, and each of the filters F1 to F7 can be the first filter and the second filter.

  The filters F1 to F7 are for capturing white light (transparent), greenish blue light, yellow-green light, yellow light, orange light, red light, and infrared light (represented as black for convenience), respectively. is there. Specifically, the spectral characteristics of the filters F1 to F7 are indicated by L1 to L7 in FIG. 14, respectively.

  In the present embodiment, the filters F1, F4, and F6 correspond to the transparent filter 2W, the yellow filter 2Y, and the red filter 2R, respectively.

  Next, a method for obtaining a data value for reproducing the incident light received in each of the filters F1 to F7 will be described.

  First, when light is incident on the image sensor 1U, the incident light is received by the corresponding first light receiving element and second light receiving element via the first filter and the second filter which are any one of the filters F1 to F7. Is done. The received light is converted into an electrical signal.

  Next, as shown in FIG. 15, the first filter and the second filter receive the data value D1 of the light received by the first filter and the data value D2 of the light received by the second filter. A wavelength data value DC corresponding to the difference in the wavelength range of light is obtained.

  In other words, the first filter and the second filter constitute an apparent color filter of a color corresponding to the difference between the respective wavelength ranges.

  For example, a blue data value can be obtained based on the filter F1 (white) and the filter F4 (yellow). A green data value can be obtained based on the filter F4 (yellow) and the filter F6 (red). Red data values that are not affected by infrared rays can be obtained from the filter F6 (red) and the filter F7 (black).

  Thereby, since the data values of the three primary colors of light can be obtained, the received incident light can be reproduced.

  Further, for example, by subtracting the filter F2 (greenish blue) and the filter F3 (yellowish green), a greenish blue (greenish blue) data value can be obtained. By the subtraction process between the filter F3 (yellowish green) and the filter F4 (yellow), a yellowish green data value is obtained. By subtracting the filter F4 (yellow) and the filter F5 (orange), a yellow data value is obtained. By subtracting the filter F5 (orange) and the filter F6 (red), an orange data value is obtained.

  That is, according to the method described above, by using two filters constituting the first filter and the second filter among the filters F1 to F7, not only the received incident light is reproduced, but also finer detail. Color extraction is possible.

  In addition, in this embodiment, although seven types of filters F1-F7 were illustrated, it cannot be overemphasized that it is not restricted to this. That is, it has the 1st wavelength range which shows the transmittance | permeability of 10% or less in the wavelength range of 350 nm-750 nm, and is 90% or more in the wavelength range longer than the said 1st wavelength range and 450 nm-1100 nm. The present embodiment does not exclude the color filter having a wavelength region that is a transmittance.

  In addition, in the image pickup device 1U according to the present embodiment, a high ratio color filter having the highest color material content ratio among the color filters is formed by dry etching, and a low ratio color filter other than the high ratio color filter is formed by a photolithography method. It can be manufactured by forming.

FIG. 3 is a front view illustrating an example of an arrangement state of filters in the image sensor according to the first embodiment of the present invention. FIG. 3 is a cross-sectional view illustrating an example of an image sensor according to the first embodiment. The graph which shows an example of the spectral transmittance about a transparent filter, a yellow filter, and a red filter. The graph which shows an example of the spectral transmittance about the apparent blue filter, green filter, and red filter obtained by the calculation of the image sensor according to the first embodiment. The graph which shows the example of the actual spectral characteristic of the conventional image pick-up element. Sectional drawing which shows an example of the image pick-up element which concerns on 2nd Embodiment. Sectional drawing which shows an example of the image pick-up element which concerns on the 3rd Embodiment of this invention. Sectional drawing which shows the example of the 1st process of the manufacturing process of the image pick-up element which concerns on 3rd Embodiment. Sectional drawing which shows the example of the 2nd process of the manufacturing process of the image pick-up element which concerns on 3rd Embodiment. Sectional drawing which shows the example of the 3rd process of the manufacturing process of the image pick-up element which concerns on 3rd Embodiment. Sectional drawing which shows the example of the 4th process of the manufacturing process of the image pick-up element which concerns on 3rd Embodiment. Sectional drawing which shows the example of the 5th process of the manufacturing process of the image pick-up element which concerns on 3rd Embodiment. The front view which shows the 1st example of the arrangement position of the light shielding film of the image pick-up element which concerns on the 4th Embodiment of this invention. It is a figure which shows an example of the spectral characteristics of the filter F1-filter F7 which concerns on the 5th Embodiment of this invention. It is a figure for demonstrating the concept of the apparent color filter which concerns on 5th Embodiment. The graph which shows the example of the relationship of the transmittance | permeability of a preferable near-infrared cut filter with respect to human visual sensitivity, the sensitivity of a light receiving element, and the sensitivity of a light receiving element. The graph which shows an example of the spectral transmittance of the color filter of three primary colors of red, green, and blue.

Explanation of symbols

  1, 1U, 9, 11, 17 ... Imaging device, 2 ... Filter layer, 2W, 10W, 12W ... Transparent filter, 2Y ... Yellow filter, 2R ... Red filter, 2V ... Violet filter, 3W ... Incident light receiving device 3W 3Y ... Yellow light receiving element, 3R ... Red light receiving element, 4 ... Operation part, 4B ... Blue operation part, 4G ... Green operation part, 4R ... Red operation part, 5 ... Semiconductor substrate, 6 ... Flattening layer, 7 ... Resin Layer, 8 ... microlens, 12 ... flattening layer, 13 ... photosensitive phenol resin, 13a ... lens matrix, 16 ... film, 18 ... effective pixel portion of image sensor, 19 ... light shielding film, 20 ... electrode portion.

Claims (13)

In an imaging device comprising a filter used to extract a specific color component of incident light and a light receiving element that observes the incident light via the filter,
The filter is
A transparent filter,
A yellow filter used to extract the yellow component;
Look including a red filter to be used in the extraction of the red component,
Comprising a transparent planarization layer covering the yellow filter and the red filter;
The image pickup device, wherein the transparent filter is formed by the transparent flattening layer . The imaging element further includes a microlens for condensing light on the light receiving element,
The imaging device according to claim 1, wherein the microlens is formed by the transparent planarization layer. In an imaging device comprising a filter used to extract a specific color component of incident light and a light receiving element that observes the incident light via the filter,
The filter is
A transparent filter,
A yellow filter used to extract the yellow component;
Look including a red filter to be used in the extraction of the red component,
The number of pixels of the yellow filter is equal to the total number of pixels of the transparent filter and the red filter. The light receiving element is
An incident light receiving element for observing the incident light via the transparent filter;
A yellow light receiving element for observing the incident light via the yellow filter;
A red light receiving element for observing the incident light via the red filter;
Subtracting the observation result observed by the yellow light receiving element from the observation result observed by the incident light receiving element, and calculating means for obtaining the blue observation result;
A calculation means for subtracting the observation result observed with the red light receiving element from the observation result observed with the yellow light receiving element to obtain a green observation result;
The imaging device according to claim 1, further comprising:   5. The transparent filter, the yellow filter, and the red filter are adjacently arranged in a grid pattern to form a surface to form one unit of color separation. The imaging device according to any one of claims. The imaging device according to claim 1 , wherein the transparent filter absorbs ultraviolet rays in a wavelength region shorter than 400 nm . The light-shielding film for suppressing reflection and transmission of other light except the light which injects into the said light receiving element among the said incident light is further comprised , The any one of Claim 1 thru | or 6 characterized by the above-mentioned. Image sensor. Comprising a substrate on which the light receiving element is disposed;
The imaging device according to claim 7, wherein the light shielding film is provided on an incident side of the incident light of the substrate and is provided in a region other than a region where the incident light is incident on the light receiving device. 9. The imaging device according to claim 7, wherein the light shielding film has an ultraviolet absorbing function or a film that absorbs ultraviolet rays is laminated. 10. The image pickup device according to claim 7, wherein the light-shielding film has a near infrared absorption function, or a film that absorbs near infrared rays is laminated. An image sensor that detects an intensity value of light existing in a specific wavelength region of incident light; and
An imaging device comprising: an arithmetic unit that reproduces incident light based on an intensity value of light detected by the imaging element;
The image sensor is
A semiconductor substrate;
A photoelectric conversion element formed on the semiconductor substrate for receiving incident light;
A transparent filter formed on the photoelectric conversion element and transmitting the incident light;
A red filter formed on the photoelectric conversion element and used to extract a red component of the incident light;
A yellow filter formed on the photoelectric conversion element and used to extract a yellow component of the incident light;
A transparent planarization layer formed so as to cover the yellow filter and the red filter;
A microlens formed above the yellow filter and the red filter;
With
The computing means is
Means for subtracting the intensity value of the incident light received via the yellow filter from the intensity value of the incident light received via the transparent filter, and calculating the value of the blue component of the incident light;
Means for subtracting the intensity value of the incident light received via the red filter from the intensity value of the incident light received via the yellow filter, and calculating the value of the green component of the incident light;
Means for calculating the value of the red component of the incident light based on the intensity value of the incident light received via the red filter;
With
The imaging device, wherein the transparent filter is formed by the transparent planarization layer. The imaging device according to claim 11, wherein the microlens is formed by the transparent planarization layer. An image sensor that detects an intensity value of light existing in a specific wavelength region of incident light; and
An imaging device comprising: an arithmetic unit that reproduces incident light based on an intensity value of light detected by the imaging element;
The image sensor is
A semiconductor substrate;
A photoelectric conversion element formed on the semiconductor substrate for receiving incident light;
A transparent filter formed on the photoelectric conversion element and transmitting the incident light;
A red filter formed on the photoelectric conversion element and used to extract a red component of the incident light;
A yellow filter formed on the photoelectric conversion element and used to extract a yellow component of the incident light;
A transparent planarization layer formed so as to cover the yellow filter and the red filter;
A microlens formed above the yellow filter and the red filter;
With
The computing means is
Means for subtracting the intensity value of the incident light received via the yellow filter from the intensity value of the incident light received via the transparent filter, and calculating the value of the blue component of the incident light;
Means for subtracting the intensity value of the incident light received via the red filter from the intensity value of the incident light received via the yellow filter, and calculating the value of the green component of the incident light;
Means for calculating the value of the red component of the incident light based on the intensity value of the incident light received via the red filter;
With
An imaging apparatus, wherein the number of pixels of the yellow filter is equal to the total number of pixels of the transparent filter and the red filter.

Images