KR20210048400A - Image sensor including color separating lens array and electronic apparatus including the image sensor - Google Patents

Abstract

Disclosed are an image sensor having a color separation lens array capable of separating and condensing incident light for each wavelength, and an electronic device including the same. The disclosed image sensor includes: a sensor substrate including a first light sensing cell and a second light sensing cell for sensing light; and a color separation lens array including a plurality of regions disposed to face each of the plurality of light sensing cells in a vertical direction. The color separation lens array separates light of a different first wavelength and light of a second wavelength included in the incident light with respect to the incident light incident on the color separation lens array, and light of a first wavelength is focused on the first light sensing cell and light of a second wavelength is focused on the second light sensing cell.

Description

An image sensor including a color separating lens array and an electronic apparatus including the image sensor.

The disclosed embodiments relate to an image sensor including a color separation lens array and an electronic device including an image sensor, and more particularly, an image sensor and an image including a color separation lens array capable of separating and condensing incident light by wavelength. It relates to an electronic device including a sensor.

Image sensors typically detect the color of incident light using a color filter. However, since the color filter absorbs light of a color other than the light of the corresponding color, the light utilization efficiency may be deteriorated. For example, when an RGB color filter is used, only 1/3 of the incident light is transmitted and the remaining 2/3 is absorbed, so that the light utilization efficiency is only about 33%. Therefore, in the case of a color display device or a color image sensor, most of the light loss occurs in the color filter.

An image sensor with improved light utilization efficiency is provided by using a color separation lens array capable of separating and condensing incident light by wavelength.

It provides an electronic device including an image sensor.

An image sensor according to an embodiment includes: a sensor substrate including a first light sensing cell and a second light sensing cell for sensing light; A transparent spacer layer disposed on the sensor substrate; And a color separation lens array disposed on the spacer layer, wherein the color separation lens array is disposed to face the first light sensing cell in a vertical direction and is disposed along a first region having a first pattern and a vertical direction. It is disposed facing the second light sensing cell and includes a second region having a second pattern different from the first pattern, and the first pattern and the second pattern are formed with respect to incident light incident on the color separation lens array. , By separating light of a first wavelength and light of a second wavelength different from each other included in the incident light, condensing light of a first wavelength to the first light sensing cell, and light of a second wavelength to the second light sensing cell. Can be condensed.

The spacer layer may have a thickness corresponding to a focal length of the color separation lens array at a center wavelength of a wavelength band of incident light color-separated by the color separation lens array.

When the theoretical thickness of the spacer layer is h _t , the pitch of each photosensitive cell is p, the refractive index of the spacer layer is n, and the center wavelength of the wavelength band of incident light color-separated by the color separation lens array is λ ₀ . , The theoretical thickness of the spacer layer is

이고,

ego,

The actual thickness h of the spacer layer may be h _t -p ≤ h ≤ h _t + p.

In the first pattern and the second pattern, at a position immediately after passing through the color separation lens array, light of a first wavelength forms a phase distribution of 2Nπ at a position corresponding to the center of the first light sensing cell. 2 At a position corresponding to the center of the photosensitive cell, a phase distribution of (2N-1)π can be formed. Here, N is an integer greater than 0.

The first pattern and the second pattern have a phase distribution of (2M-1)π at a position immediately after passing through the color separation lens array and at a position corresponding to the center of the first light sensing cell. And at a position corresponding to the center of the second light sensing cell, a phase distribution of 2Mπ may be formed. Here, M is an integer greater than 0.

The first region includes a first dielectric having a first refractive index and forming a first pattern, and a second dielectric having a second refractive index less than the first refractive index and filled between the first dielectrics, A first pattern may be formed such that the first dielectric is present even in a vertical cross section.

The second region includes a first dielectric having a first refractive index and forming a second pattern, and a second dielectric having a second refractive index less than the first refractive index and filled between the first dielectrics, A second pattern may be formed such that the first dielectric is present even in a vertical cross section.

The sensor substrate further includes a third photo-sensing cell and a fourth photo-sensing cell, and the color separation lens array is disposed to face the third photo-sensing cell in a vertical direction, and includes the first pattern and the second pattern. A third region having a different third pattern and a fourth region disposed to face the fourth light sensing cell along a vertical direction and having a fourth pattern different from the first to third patterns may be further included.

The third area is disposed adjacent to the first area and disposed in a diagonal direction of the second area, and the fourth area is disposed adjacent to the second area and disposed in a diagonal direction of the first area, The first to fourth patterns separate light of different first wavelength, light of a second wavelength, and light of a third wavelength included in the incident light with respect to the incident light incident on the color separation lens array. , Light of a first wavelength is condensed to the first and fourth light sensing cells, light of a second wavelength is condensed to the second light sensing cell, and light of a third wavelength is condensed to the third light sensing cell I can make it.

The first to fourth patterns have a phase of 2Nπ at a position immediately after passing through the color separation lens array and at a position corresponding to the center of the first light sensing cell and the fourth light sensing cell. A distribution may be formed, and a phase distribution of (2N-1)π may be formed at positions corresponding to the centers of the second and third light sensing cells.

In the first to fourth patterns, at a position immediately after passing through the color separation lens array, light of a second wavelength is at a position corresponding to the center of the first photosensitive cell and the center of the fourth photosensitive cell. A phase distribution of (2M-1)π is formed and a phase distribution of 2Mπ is formed at a position corresponding to the center of the second photosensitive cell, and (2M-2) at a position corresponding to the center of the third photosensitive cell. It is possible to form a phase distribution larger than π and smaller than (2M-1)π.

In the first to fourth patterns, at a position immediately after passing through the color separation lens array, light of a third wavelength is at a position corresponding to the center of the first photosensitive cell and the center of the fourth photosensitive cell. A phase distribution of (2L-1)π is formed, and a phase distribution larger than (2L-2)π and smaller than (2L-1)π is formed at a position corresponding to the center of the second light sensing cell, and the third light It is possible to form a phase distribution of 2Lπ at a position corresponding to the center of the sensing cell. Here, L is an integer greater than 0.

In the first to fourth patterns, among incident light incident on the first region of the color separation lens array, the light of the first wavelength proceeds toward the center of the first light sensing cell corresponding to the first region, The light of the second wavelength advances toward the center of the second light-sensing cell around the first light-sensing cell corresponding to the first area, and the light of the third wavelength is a first light-sensing cell corresponding to the first area. It can proceed toward the center of the surrounding third light sensing cell.

In the first to fourth patterns, among incident light incident on the second region of the color separation lens array, light of a second wavelength proceeds toward the center of the second light sensing cell corresponding to the second region, The light of the first wavelength proceeds toward the center of the first and fourth light sensing cells around the second light sensing cell corresponding to the second region, and the light of the third wavelength corresponds to the second region. It may proceed toward the center of the third light sensing cell around the second light sensing cell.

In the first to fourth patterns, among incident light incident on a third area of the color separation lens array, light of a third wavelength proceeds toward the center of the third light sensing cell corresponding to the third area, The light of the first wavelength advances toward the center of the first and fourth light sensing cells around the third light sensing cell corresponding to the third region, and the light of the second wavelength corresponds to the third region. It may proceed toward the center of the second light sensing cell around the third light sensing cell.

In the first to fourth patterns, among incident light incident on a fourth region of the color separation lens array, light of a first wavelength proceeds toward a central portion of a fourth light sensing cell corresponding to the fourth region, The light of the second wavelength advances toward the center of the second light-sensing cell around the fourth light-sensing cell corresponding to the fourth area, and the light of the third wavelength is a fourth light-sensing cell corresponding to the fourth area. It can proceed toward the center of the surrounding third light sensing cell.

For example, the light of the first wavelength may be green light, the light of the second wavelength may be blue light, and the light of the third wavelength may be red light.

The first pattern and the fourth pattern are two-way symmetric, the second and third patterns are four-way symmetric, and the fourth pattern may have a shape rotated by 90 degrees with respect to the first pattern.

The color separation lens array includes a plurality of unit pattern arrays including a first region, a second region, a third region, and a fourth region adjacent to each other, and the plurality of unit pattern arrays are arranged in a two-dimensional manner. Can be.

The color separation lens array is disposed to protrude from the edge of the sensor substrate, and a plurality of first regions, a plurality of second regions, and a plurality of third regions that do not face any light sensing cells of the sensor substrate in a vertical direction , And a plurality of fourth regions may be further included.

The image sensor is disposed between the sensor substrate and the spacer layer, and may further include a color filter layer including a plurality of color filters.

An image sensor according to another embodiment includes: a sensor substrate including first to fourth light sensing cells for sensing light; A transparent spacer layer disposed on the sensor substrate; And a color separation lens array disposed on the spacer layer, wherein the color separation lens array is disposed in a vertical direction to face the first light sensing cell, and includes a first region having a first pattern and a vertical direction. A second region disposed to face the second light sensing cell and having a second pattern different from the first pattern, disposed to face the third light sensing cell in a vertical direction, and the first pattern and the second pattern A third region having a different third pattern, and a fourth region disposed to face the fourth light sensing cell along a vertical direction and having a fourth pattern different from the first to third patterns, and the fourth region The third area is disposed adjacent to the first area and disposed in a diagonal direction of the second area, and the fourth area is disposed adjacent to the second area and disposed in a diagonal direction of the first area. The first pattern and the fourth pattern are two-way symmetric, the second and third patterns are four-way symmetric, and the fourth pattern may have a shape rotated by 90 degrees with respect to the first pattern.

An imaging device according to another embodiment includes: an objective lens for forming an optical image by focusing light reflected from an object; And the above-described image sensor for converting the optical image formed by the objective lens into an electrical image signal.

Also, an electronic device according to another embodiment may include the above-described imaging device.

Since the disclosed color separation lens array can separate and condense light by wavelength without absorbing or blocking incident light, it is possible to improve the light utilization efficiency of the image sensor. In addition, the image sensor employing the disclosed color separation lens array can maintain the Bayer pattern method generally adopted in the image sensor, and thus can utilize the pixel structure and image processing algorithm of the existing image sensor. In addition, an image sensor employing the disclosed color separation lens array does not require a separate microlens for condensing light onto a pixel.

1 is a block diagram of an image sensor according to an exemplary embodiment.
2A to 2C exemplarily show various pixel arrangements of a pixel array of an image sensor.
3 is a conceptual diagram showing a schematic structure and operation of a color separation lens array according to an exemplary embodiment.
4 is a plan view illustrating a unit pattern array of a color separation lens array that can be applied to a Bayer pattern type image sensor.
5 is a cross-sectional view illustrating a vertical cross section of the unit pattern array shown in FIG. 4 taken along the line AA′.
FIG. 6 is a cross-sectional view illustrating a vertical cross section of the unit pattern array shown in FIG. 4 taken along line BB′.
7 is a plan view illustrating an arrangement of a color separation lens array including a plurality of unit pattern arrays illustrated in FIG. 4.
8A and 8B are views each showing a pixel array of an image sensor according to an exemplary embodiment from different cross-sections.
9A illustrates an example of a first region of the unit pattern array illustrated in FIG. 4, and FIG. 9B illustrates a corresponding pixel of an image sensor and a neighboring pixel thereof.
10A is an exemplary view of a second area of the unit pattern array illustrated in FIG. 4, and FIG. 10B is an exemplary view of a corresponding pixel of an image sensor and surrounding pixels thereof.
FIG. 11A exemplarily shows a third area of the unit pattern array illustrated in FIG. 4, and FIG. 11B exemplarily shows a pixel of an image sensor corresponding thereto and a pixel surrounding the same.
12A is an exemplary view of a fourth region of the unit pattern array illustrated in FIG. 4, and FIG. 12B is an exemplary view of a pixel of an image sensor corresponding thereto and a pixel surrounding it.
13A and 13B are diagrams for computational simulation of a phase distribution of blue light passing through a color separation lens array and a focusing distribution of blue light in an opposing light sensing cell, and FIG. 13C is a second color separation lens array corresponding to a blue pixel. The moving direction of the blue light incident on the region and its periphery is shown as an example, and FIG. 13D exemplarily shows a micro lens array that acts equivalently to a color separation lens array for blue light.
14A and 14B are diagrams for computational simulation of the phase distribution of green light passing through the color separation lens array and the focusing distribution of green light in an opposing light sensing cell, and FIG. 14C is a first diagram of a color separation lens array corresponding to a green pixel. The moving direction of the green light incident on the region and its periphery is shown as an example, and FIG. 14D exemplarily shows a micro lens array that acts equivalently to a color separation lens array for green light.
15A and 15B are diagrams that simulate the phase distribution of red light passing through the color separation lens array and the focusing distribution of red light in the opposing light sensing cells, and FIG. 15C is a third color separation lens array corresponding to a red pixel. The traveling direction of the red light incident on the region and its periphery is shown as an example, and FIG. 15D exemplarily shows a micro lens array that acts equivalently to a color separation lens array for red light.
16A to 16E are graphs exemplarily showing changes in efficiency of the color separation lens array according to the distance between the color separation lens array and the sensor substrate when the pitch of the photosensitive cells is 0.7 μm.
17A to 17E are graphs exemplarily showing changes in efficiency of the color separation lens array according to the distance between the color separation lens array and the sensor substrate when the pitch of the light sensing cells is 0.8 μm.
18A to 18E are graphs exemplarily showing changes in efficiency of the color separation lens array according to the distance between the color separation lens array and the sensor substrate when the pitch of the photosensitive cells is 1.0 μm.
19 is a graph exemplarily showing spectral distributions of light incident on a blue pixel, a green pixel, and a red pixel of the image sensor illustrated in FIGS. 8A and 8B.
20 is a plan view exemplarily showing a shape of a unit pattern array of a color separation lens array according to another exemplary embodiment.
21 is a plan view exemplarily showing a shape of a unit pattern array of a color separation lens array according to another exemplary embodiment.
22A and 22B are schematic cross-sectional views illustrating a pixel array of an image sensor according to another exemplary embodiment, respectively.
23 is a plan view illustrating a color separation lens array according to another exemplary embodiment.
24 is a cross-sectional view showing a schematic structure of a pixel array of an image sensor including the color separation lens array shown in FIG. 23.
25 is a schematic block diagram of an electronic device including an image sensor according to embodiments.
26 to 36 show various examples of electronic devices to which an image sensor according to embodiments is applied.

Hereinafter, an image sensor including a color separation lens array and an electronic device including the same will be described in detail with reference to the accompanying drawings. The described embodiments are merely exemplary, and various modifications are possible from these embodiments. In the following drawings, the same reference numerals refer to the same components, and the size of each component in the drawings may be exaggerated for clarity and convenience of description.

Hereinafter, the expression described as "upper" or "upper" may include not only those that are directly above/below/left/right in contact, but also those that are above/below/left/right in a non-contact manner.

Terms such as first and second may be used to describe various components, but are used only for the purpose of distinguishing one component from other components. These terms are not intended to limit differences in materials or structures of components.

Singular expressions include plural expressions unless the context clearly indicates otherwise. In addition, when a part "includes" a certain component, it means that other components may be further included rather than excluding other components unless specifically stated to the contrary.

In addition, terms such as "... unit" and "module" described in the specification mean units that process functions or operations, which may be implemented as hardware or software, or as a combination of hardware and software.

The use of the term "above" and similar reference terms may correspond to both the singular and the plural.

The steps constituting the method may be performed in any suitable order unless there is a clear statement that the steps constituting the method should be performed in the order described. In addition, the use of all exemplary terms (eg, etc.) is merely for describing technical ideas in detail, and the scope of the rights is not limited by these terms unless limited by claims.

1 is a schematic block diagram of an image sensor according to an exemplary embodiment. Referring to FIG. 1, the image sensor 1000 may include a pixel array 1100, a timing controller 1010, a row decoder 1020, and an output circuit 1030. The image sensor may be a charge coupled device (CCD) image sensor or a complementary metal oxide semiconductor (CMOS) image sensor.

The pixel array 1100 includes pixels that are two-dimensionally arranged along a plurality of rows and columns. The row decoder 1020 selects one of the rows of the pixel array 1100 in response to a row address signal output from the timing controller 1010. The output circuit 1030 outputs a light detection signal in column units from a plurality of pixels arranged along the selected row. To this end, the output circuit 1030 may include a column decoder and an analog to digital converter (ADC). For example, the output circuit 1030 may include a plurality of ADCs disposed for each column between the column decoder and the pixel array 1100 or one ADC disposed at an output terminal of the column decoder. The timing controller 1010, the row decoder 1020, and the output circuit 1030 may be implemented as a single chip or separate chips. A processor for processing the image signal output through the output circuit 1030 may be implemented as a single chip together with the timing controller 1010, the row decoder 1020, and the output circuit 1030.

The pixel array 1100 may include a plurality of pixels sensing light of different wavelengths. Pixels may be arranged in various ways as shown in FIGS. 2A to 2C.

First, FIG. 2A shows a Bayer pattern generally adopted in the image sensor 1000. Referring to FIG. 2A, one unit pixel includes four quadrant regions, and the first to fourth quadrants are respectively a blue pixel (B), a green pixel (G), a red pixel (R), and a green color. It can be a pixel (G). These unit pixels are repeatedly arranged two-dimensionally along a first direction (X direction) and a second direction (Y direction). In other words, two green pixels (G) are arranged in one diagonal direction within a 2×2 array-type unit pixel, and one blue pixel (B) and one red pixel (R) in the other diagonal direction, respectively. Is placed. Looking at the overall pixel arrangement, a first row in which a plurality of green pixels (G) and a plurality of blue pixels (B) are alternately arranged along a first direction, and a plurality of red pixels (R) and a plurality of green pixels (G) are The second rows alternately arranged along the first direction are repeatedly arranged.

However, the arrangement method of the pixel array 1100 is not limited only to the Bayer pattern, and various arrangement methods other than the Bayer pattern are possible. For example, referring to FIG. 2B, a magenta pixel (M), a cyan pixel (C), a yellow pixel (Y), and a green pixel (G) represent one unit pixel. The configuration of the CYGM method is also possible. Further, referring to FIG. 2C, an RGBW arrangement in which a green pixel (G), a red pixel (R), a blue pixel (B), and a white pixel (W) constitute one unit pixel is also possible. Also, although not shown, the unit pixel may have a 3×2 array form. In addition, the pixels of the pixel array 1100 may be arranged in various ways according to the color characteristics of the image sensor 1000. Hereinafter, for convenience, the pixel array 1100 of the image sensor 1000 will be described as having a Bayer pattern, but the principles of the embodiments described below may be applied to a pixel array other than a Bayer pattern.

According to an embodiment, the pixel array 1100 of the image sensor 1000 may include a color separation lens array configured to condense light of a corresponding color to each pixel. 3 is a conceptual diagram showing a schematic structure and operation of a color separation lens array according to an exemplary embodiment. Referring to FIG. 3, the unit pattern array of the color separation lens array 130 may include first to fourth regions 131, 132, 133, and 134 each having first to fourth patterns that are distinguished from each other. have. For example, the first region 131 has a first pattern, the second region 132 has a second pattern patterned in a different shape from the first pattern, and the third region 133 has a first pattern and The third pattern may have a shape different from that of the second pattern, and the fourth region 134 may have a fourth pattern patterned in a shape different from the first to third patterns.

The first to fourth regions 131, 132, 133, and 134 may be arranged on the same plane in the form of, for example, 2×2. Accordingly, the first area 131 and the second area 132 are disposed adjacent to each other in the first direction, and the third area 133 and the fourth area 134 are also disposed adjacent to each other in the first direction. do. In addition, the first region 131 and the third region 133 are disposed adjacent to each other in a second direction perpendicular to the first direction, and the third region 133 and the fourth region 134 are also arranged in the second direction. Are arranged adjacent to each other along the line. The first and fourth regions 131 and 134 are arranged along a diagonal direction, and the second and third regions 133 and 133 are arranged along different diagonal directions.

According to an embodiment, of the incident light incident on the color separation lens array 130, the light of the first wavelength λ1 is condensed in the first target region R1 facing the first region 131 along a vertical direction. , The light of the second wavelength λ2 is focused on the second target region R2 facing the second region 132 along the vertical direction, and the light of the third wavelength λ3 is focused on the third region 133 It is condensed on the third target region R3 facing along the vertical direction, and the light of the fourth wavelength λ4 is focused on the fourth target region R4 facing the fourth region 134 and along the vertical direction, The first to fourth patterns may be determined. Specific patterns of the first to fourth regions 131, 132, 133, and 134 may be variously designed according to the pixel arrangement and color characteristics of the image sensor to which the color separation lens array 130 is applied.

When the color separation lens array 130 shown in FIG. 3 is applied to the Bayer pattern type image sensor shown in FIG. 2A, the first area 131 and the fourth area 134 face the green pixel G. The second region 132 may be disposed to face the blue pixel B, and the third region 133 may be disposed to face the red pixel R. In addition, the first wavelength light λ1 and the fourth wavelength light λ4 may be green light, the second wavelength light λ2 may be blue light, and the third wavelength light λ3 may be red light.

4 is a plan view illustrating a unit pattern array of a color separation lens array that can be applied to a Bayer pattern type image sensor. Referring to FIG. 4, a first region 131 facing the green pixel G includes a first dielectric 131a forming a first pattern and a second dielectric 131b filled between the first dielectric 131a. Includes. The second region 132 facing the blue pixel B includes a first dielectric 132a forming a second pattern and a second dielectric 132b filled between the first dielectric 132a, and the red pixel ( The third region 133 facing R) includes a first dielectric 133a forming a third pattern and a second dielectric 133b filled between the first dielectric 133a, and the green pixel G The facing fourth region 134 includes a first dielectric 134a forming a fourth pattern and a second dielectric 134b filled between the first dielectric 134a.

The first region 131 and the second region 132 both face the green pixel and thus have the same shape, but their rotation directions may be different. For example, as shown in FIG. 4, the pattern of the fourth region 134 may have a shape in which the pattern of the first region 131 is rotated 90 degrees. This difference may be determined according to the arrangement of adjacent pixels. In the case of FIG. 4, blue pixels B are disposed on the left and right sides of the green pixel G facing the first area 131, and red pixels B are disposed on the left and right sides of the green pixel G facing the fourth area 134. In the difference in which R) is arranged, a pattern arranged in a different direction of rotation may be formed as described above.

All of the first dielectrics 131a, 132a, 133a, and 134a may be made of the same material, and all of the second dielectrics 131b, 132b, 133b, and 134b may be made of the same material. For example, the first dielectric 131a, 132a, 133a, 134a is made of a dielectric material having a high refractive index, such as _{TiO 2} , GaN, SiN ₃ , ZnS, ZnSe, Si ₃ N _{4, etc., and having a low absorption rate in the visible light band.} The second dielectrics 131b, 132b, 133b, and 134b have a _{low refractive index such as air, SiO 2} , and silanol-based spin on glass (SOG) and have a low absorption rate in the visible light band. It can be made of a dielectric material. When the second dielectrics 131b, 132b, 133b, and 134b are made of air, the color separation lens array 130 shown in FIG. 4 can be formed simply by etching the first dielectrics 131a, 132a, 133a, and 134a. have.

FIG. 5 is a cross-sectional view illustrating a vertical cross section of the unit pattern array shown in FIG. 4 taken along the AA′ line (X direction), and FIG. 6 is a BB′ line (Y It is a cross-sectional view showing a vertical cross section cut along the direction) as an example. 5 and 6, the first dielectrics 131a, 132a, 133a, and 134a and the second dielectrics 131b, 132b, 133b, and 134b may extend in parallel in a vertical direction. The shape of the vertical cross section shown in FIGS. 5 and 6 is exemplary, and the shape of the vertical cross section of the first to fourth regions 131, 132, 133 and 134 varies according to the positions of the AA' line and the BB' line. I can. For example, as the line AA' moves along the Y direction, the shape of the vertical section shown in FIG. 5 changes, and as the line BB' moves along the X direction, the shape of the vertical section shown in FIG. It will change. Regardless of the change in the shape of the vertical section, the first dielectrics 131a, 132a, 133a, 134a and the second dielectrics 131b, 132b in all vertical sections of the first to fourth regions 131, 132, 133, 134 , 133b, 134b) may exist together.

7 is a plan view illustrating an arrangement of a color separation lens array including a plurality of unit pattern arrays illustrated in FIG. 4. As shown in FIG. 7, the color separation lens array 130 may have a form in which a 2×2 unit pattern array shown in FIG. 4 is repeatedly two-dimensionally arranged.

Hereinafter, an example in which the above-described color separation lens array 130 is applied to the pixel array 1100 of the image sensor 1000 will be described in more detail.

8A and 8B are views each showing a pixel array of an image sensor according to an exemplary embodiment from different cross-sections. 8A and 8B, the pixel array 1100 of the image sensor 1000 includes a sensor substrate 110 including a plurality of light sensing cells 111, 112, 113, and 114 for sensing light, and a sensor substrate. A transparent spacer layer 120 disposed on the (110) and a color separation lens array 130 disposed on the spacer layer 120 are included.

The sensor substrate 110 includes a first photo-sensing cell 111, a second photo-sensing cell 112, a third photo-sensing cell 113, and a fourth photo-sensing cell 114 that converts light into an electrical signal. Can include. The first light sensing cell 111, the second light sensing cell 112, the third light sensing cell 113, and the fourth light sensing cell 114 may be alternately arranged. For example, as shown in FIG. 8A, the first light sensing cells 111 and the second light sensing cells 112 are alternately arranged along the first direction (X direction). In addition, in a cross section having a different position in the Y direction, as shown in FIG. 8B, the third and fourth light sensing cells 113 and 114 may be alternately arranged. The division of the area is for sensing incident light by dividing the incident light into a pixel unit. For example, the first light sensing cell 111 and the fourth light sensing cell 114 receive light of a first wavelength corresponding to the first pixel. Sensing, the second light sensing cell 112 senses light of a second wavelength corresponding to the second pixel, and the third light sensing cell 113 senses light of a third wavelength corresponding to the third pixel. I can. Hereinafter, the light of the first wavelength is illustrated as green light, the light of the second wavelength is blue light, and the light of the third wavelength is red light, and the first pixel, the second pixel, and the third pixel are green pixels (G) and blue light, respectively. It may be a pixel B or a red pixel R, but is not limited thereto. Although not shown at the boundary between cells, a separator for cell separation may be further formed.

The spacer layer 120 serves to maintain a constant gap between the sensor substrate 110 and the color separation lens array 130 while supporting the color separation lens array 130 on the sensor substrate 110. The spacer layer 120 is a material transparent to visible light, for example, SiO ₂ , silanol-based glass (SOG; siloxane-based spin on glass), the first dielectrics 131a and 132a of the color separation lens array 130, It may be made of a dielectric material having a refractive index lower than those of 133a and 134a and having a low absorption rate in the visible light band. The spacer layer 120 may be made of the same material as the second dielectrics 131b, 132b, 133b, and 134b.

As shown in FIG. 8A, the color separation lens array 130 has a first region 131 and a second region 132 alternately arranged along a first direction (X direction), and a position in the Y direction different from each other. In cross section, as shown in FIG. 8B, the third region 133 and the fourth region 134 may be alternately arranged along the first direction (X direction). The first region 131 is disposed to face the first light sensing cell 111 with the spacer layer 120 therebetween, and the second region 132 detects the second light with the spacer layer 120 therebetween. It is disposed facing the cell 112, the third area 133 is disposed facing the third light sensing cell 113 with the spacer layer 120 therebetween, and the fourth area 134 is a spacer layer ( It may be disposed to face the fourth light sensing cell 111 with 120 interposed therebetween. Then, for example, of the incident light incident on the color separation lens array 130, the green light is formed with the first light sensing cell 111 and the fourth region 134 facing along the vertical direction to the first region 131. The fourth light sensing cell 114 facing along the vertical direction is focused, the blue light is focused on the second area 132 and the second light sensing cell 112 facing along the vertical direction, and the red light is focused on the third area Light may be focused on the third light sensing cell 113 facing along the vertical direction to the 133.

In the color separation lens array 130 applied to the Bayer pattern type image sensor, the first to fourth patterns of the first to fourth regions 131, 132, 133, and 134 may have a predetermined rule. For example, FIG. 9A exemplarily shows a pattern of the first region 131 of the unit pattern array shown in FIG. 4, and FIG. 9B exemplarily shows a pixel of an image sensor corresponding thereto and a pixel surrounding it. Referring to FIG. 9B, a blue pixel B is disposed in a left-right direction of a green pixel G corresponding to the first region 131 and a red pixel R is disposed in a vertical direction. Green pixels corresponding to the fourth region 134 are disposed in a diagonal direction of the green pixels G corresponding to the first region 131, and are not displayed in FIG. 9B. Therefore, among the transmitted light that has passed through the first region 131, in order to obtain the same optical effect as the blue light proceeds in the left and right direction of the first region 131 and the red light proceeds in the vertical direction of the first region 131, The first pattern of the first region 131 may have a 2-fold symmetry. For example, as shown in FIG. 9A, the first pattern of the first region 131 is symmetrical to the first axis (I) along the Y direction and symmetrical to the second axis (II) along the X direction. I can.

10A is an exemplary view of the shape of the second region 132 of the unit pattern array illustrated in FIG. 4, and FIG. 10B is an exemplary view of a pixel of an image sensor corresponding thereto and a pixel surrounding it. Referring to FIG. 10B, green pixels G are disposed in the left and right directions and vertical directions of the blue pixels B corresponding to the second region 132. In addition, red pixels R are disposed in two diagonal directions intersecting. Therefore, among the transmitted light passing through the second region 132, the green light proceeds in the left and right directions and the vertical direction of the second region 132, and the red light has the same optical effect as proceeding in the diagonal direction of the second region 132. To obtain, the second pattern of the second region 132 may have a 4-fold symmetry. For example, as shown in FIG. 10A, the second pattern of the second region 132 is symmetrical to the first axis (I) along the Y direction, and is symmetrical to the second axis (II) along the X direction. , It may be symmetrical to the third axis (III) and the fourth axis (IV) along the diagonal direction.

FIG. 11A is an exemplary view showing the shape of the third area 133 of the unit pattern array illustrated in FIG. 4, and FIG. 11B is an exemplary view showing pixels of an image sensor corresponding thereto and surrounding pixels thereof. Referring to FIG. 11B, green pixels G are disposed in the left and right directions and up and down directions of the red pixels R corresponding to the third area 133. In addition, blue pixels B are disposed in two diagonal directions intersecting. Therefore, among the transmitted light that has passed through the third area 133, the green light proceeds in the left and right directions and the vertical direction of the third area 133, and the blue light produces the same optical effect as the diagonal direction of the third area 133. To obtain, the third pattern of the third region 133 may be four-way symmetrical. For example, as shown in FIG. 11A, the third pattern of the third region 133 is symmetrical to the first axis (I) along the Y direction, and is symmetrical to the second axis (II) along the X direction. , It may be symmetrical to the third axis (III) and the fourth axis (IV) along the diagonal direction.

12A is an exemplary view of the shape of the fourth region 134 of the unit pattern array illustrated in FIG. 4, and FIG. 12B is an exemplary view of a pixel of an image sensor corresponding thereto and pixels surrounding the same. Referring to FIG. 12B, a red pixel R is disposed in a left-right direction of a green pixel G corresponding to the fourth region 134 and a blue pixel B is disposed in a vertical direction. Green pixels corresponding to the first area 131 are arranged in a diagonal direction, and are not shown in FIG. 12B. Accordingly, in the transmitted light passing through the fourth region 134, the red light proceeds in the left and right direction of the fourth region 134 and the blue light proceeds in the vertical direction of the fourth region 401 in order to obtain the same optical effect, The fourth pattern of the fourth region 134 may be two-way symmetric. For example, as shown in FIG. 12A, the fourth pattern of the fourth region 134 may be symmetrical to the first axis (I) along the Y direction and symmetrical to the second axis (II) along the X direction. . Also, the pixel arrangement shown in FIG. 12B is rotated by 90 degrees with respect to the pixel arrangement shown in FIG. 9B. Accordingly, the fourth pattern of the fourth region 134 may have the same shape as rotated 90 degrees with respect to the first pattern of the first region 131.

In the color separation lens array 130 applied to the Bayer pattern type image sensor, as another rule of the first to fourth patterns of the first to fourth regions 131, 132, 133, 134, a color separation lens array The first to fourth patterns of the first to fourth regions 131, 132, 133 and 134 may be designed so that the blue light, green light, and red light transmitted through 130 have a predetermined target phase distribution. For example, a first region adjacent to the second region 132 forms a phase in which blue light transmitted through the color separation lens array 130 is condensed to the position of the blue pixel B corresponding to the second region 132 The first to fourth patterns of the first to fourth regions 131, 132, 133 and 134 may be determined to form a phase that does not proceed to positions corresponding to the 131 and the fourth regions 134. .

In addition, a phase in which green light transmitted through the color separation lens array 130 is condensed to the positions of the green pixels G corresponding to the first region 131 and the fourth region 134 is formed, and the first region 131 And the first to fourth regions 131, 132, 133 and 134 to form a phase that does not proceed to positions corresponding to the second region 132 and the third region 133 adjacent to the fourth region 134. ) Of the first to fourth patterns may be determined.

In addition, a phase in which red light transmitted through the color separation lens array 130 is condensed to the red pixel R corresponding to the third region 133 is formed, and the first region 131 adjacent to the third region 133 and First to fourth patterns of the first to fourth regions 131, 132, 133 and 134 may be determined to form a phase that does not proceed to a position corresponding to the fourth region 134.

For example, the target phase distribution to be implemented by the color separation lens array 130 is a second region in which the phase of blue light at a position passing through the color separation lens array 130 corresponds to the second light sensing cell 112 ( 2Mπ at the center of 132, and (2M) at the center of the first region 131 corresponding to the first light sensing cell 111 and the center of the fourth region 134 corresponding to the fourth light sensing cell 114 The distribution may be greater than (2M-2)π and smaller than (2M-1)π in the center of the third region 133 corresponding to the third light sensing cell 113 and is -1)π. Here, M is an integer greater than 0. In other words, the phase of blue light at the position immediately after passing through the color separation lens array 130 is maximized at the center of the second region 132, and becomes concentric as the distance from the center of the second region 132 increases. It gradually decreases, and is locally minimized in the center of the third region 133. For example, in the case of M=1, the phase of blue light at a position passing through the color separation lens array 130 is 2π from the center of the second region 132, and the center of the first region 131 and the fourth region ( It may be π at the center of 134 and about 0.2π to 0.7π at the center of the third region 133.

In addition, the phase of the green light at the position passing through the color separation lens array 130 is the center of the first region 131 corresponding to the first light sensing cell 111 and the first light sensing cell 114 corresponding to the fourth light sensing cell 114. 4 2Nπ at the center of the area 134 and at the center of the second area 132 corresponding to the second light sensing cell 112 and the center of the third area 132 corresponding to the third sensing cell 113 ( It may be 2N-1)π. Here, N is an integer greater than 0. In other words, the phase of the green light at the position immediately after passing through the color separation lens array 130 becomes maximum at the center of the first region 131 and the center of the fourth region 134, and the first region 131 As the distance from the center of the fourth area 134 and the center of the fourth area 134 gradually decreases in a concentric circle shape, the center of the second area 132 and the center of the third area 132 may be minimized. For example, in the case of N=1, the phase of green light at a position passing through the color separation lens array 130 is 2π at the center of the first region 131 and the center of the fourth region 134, and the second region ( It may be π at the center of 132 and the center of the third area 132.

In addition, the phase of the red light at the position passing through the color separation lens array 130 is 2Lπ at the center of the third area 133 corresponding to the third light sensing cell 113 and corresponds to the first light sensing cell 111. The center of the fourth region 134 corresponding to the first region 131 and the fourth light sensing cell 114 is (2L-1) π and a second region corresponding to the second light sensing cell 112 ( At the center of 132), it may be larger than (2L-2)π and smaller than (2L-1)π. Here, L is an integer greater than 0. In other words, the phase of the red light at the position immediately after passing through the color separation lens array 130 becomes a maximum in the center of the third area 133, and becomes concentric as the distance from the center of the third area 133 increases. It gradually becomes smaller and becomes a local minimum in the center of the second region 132. For example, in the case of L=1, the phase of red light at a position passing through the color separation lens array 130 is 2π from the center of the third area 133, and the center of the first area 131 and the fourth area ( It may be π at the center of the second region 134 and about 0.2π to 0.7π at the center of the second region 132.

As mentioned above, the target phase distribution refers to the position immediately after passing through the color separation lens array 130, that is, the phase distribution of light on the lower surface of the color separation lens array 130 or the upper surface of the spacer layer 120. do. When the light passing through the color separation lens array 130 has such a phase distribution, the first to fourth wavelengths of light are collected in the corresponding first to fourth light sensing cells 111 to 114, respectively. . In other words, the light transmitted through the color separation lens array 130 may be divided according to a wavelength and proceed in different directions to obtain an optical effect of condensing.

In this way, a predetermined propagation distance requirement may be determined so that light of a corresponding wavelength is condensed to the corresponding light sensing cell, and accordingly, the thickness h of the spacer layer 120 may be determined. The thickness h of the spacer layer 120 may vary depending on the wavelength λ that is a branching target, the pixel size, and the arrangement period p of the photosensitive cells. The thickness (h) of the spacer layer 120 may be greater than the center wavelength (λ) of the visible light wavelength band to be branched, and compared to the photosensitive cell arrangement period (p), which is the distance between the centers of adjacent photosensitive cells, 1p It can be in the range of ~3p. Specifically, the thickness h of the spacer layer 120 may range from 500 nm to 5 μm. For more detailed information about setting the thickness h of the spacer layer 120, referring to FIGS. 16A to 16E, 17A to 17E, and 18A to 18E, it will be described later.

13A and 13B are diagrams that simulate the phase distribution of blue light passing through the color separation lens array and the focusing distribution of blue light in an opposing photosensitive cell, and FIG. 13C is a color separation lens array corresponding to the blue pixel (B). The second region of and the direction of blue light incident thereto are exemplarily shown, and FIG. 13D exemplarily shows a microlens array that acts equivalently to a color separation lens array for blue light.

Referring to the phase distribution illustrated in FIG. 13A, the phase at the center of the region corresponding to the blue pixel B is approximately 2π, and the phase at the center of the region corresponding to the adjacent green pixel G is approximately π. Value, and the phase at the center of the area corresponding to the red pixel R in the diagonal direction is approximately smaller than π (eg, about 0.2π to 0.7π). This phase distribution may represent a focusing distribution of blue light as shown in FIG. 13B. Most of the blue light is condensed in the area corresponding to the blue pixel B, and the blue light hardly reaches the area corresponding to the other pixel.

As a result, the second region 132 corresponding to the blue pixel B and the blue light incident thereto pass through the color separation lens array 130 and then proceed as shown in FIG. 13C. For example, of incident light incident on some of the second region 132 and other regions surrounding the second region 132 of the color separation lens array 130, blue light is the second region directly under the second region 132. It is condensed in the center of the light sensing cell 112. In other words, one blue pixel B includes blue light coming from the second region 132 corresponding to the blue pixel B, and two first regions 131 adjacent to the second region 132 in the horizontal direction. Blue light coming from, blue light coming from two fourth areas 134 adjacent to the second area 132 in a vertical direction, and four third areas 113 adjacent to the second area 132 in a diagonal direction. Blue light that comes is incident.

Accordingly, as shown in FIG. 13D, the color separation lens array 130 may play an equivalent role to an array of a plurality of micro lenses ML1 arranged around the second light sensing cell 112 for blue light. . Since each equivalent microlens ML1 is larger than the corresponding second light sensing cell 112, the second light sensing cell 112 as well as the blue light incident on the region of the second light sensing cell 112 Blue light incident to another surrounding area may also be condensed to the second light sensing cell 112. For example, each microlens ML1 is about 4 times larger than the corresponding second light sensing cell 112, and the four sides of each microlens ML1 are parallel to the four sides of the second light sensing cell 112. can do.

14A and 14B are diagrams for computational simulation of the phase distribution of green light passing through the color separation lens array and the focusing distribution of green light in an opposing light sensing cell, and FIG. 14C is a first diagram of a color separation lens array corresponding to a green pixel. The moving direction of the green light incident on the area, the fourth area, and the periphery thereof is shown as an example, and FIG. 14D exemplarily shows a microlens array that acts equivalently to a color separation lens array for green light.

Looking at the phase distribution illustrated in FIG. 14A, the phase at the center of the area corresponding to the green pixel G is approximately 2π, and at the center of the area corresponding to the adjacent blue pixel B and the red pixel R. The phase roughly represents the value of π. This phase distribution may represent a focusing distribution of green light as shown in FIG. 14B. The green light is divided into areas corresponding to the two green pixels G and condensed, and the green light hardly reaches the areas corresponding to the other pixels.

As a result, the first and fourth regions 131 and 134 corresponding to the green pixel G and the green light incident thereto pass through the color separation lens array 130 and then proceed as shown in FIG. 14C. do. For example, among incident light incident on a part of the first region 131 and other regions surrounding the first region 131 of the color separation lens array 130, green light is the first region directly under the first region 131. It is condensed in the center of the light sensing cell 111. Also, although not shown, among the incident light incident on some of the fourth region 134 and other regions surrounding the fourth region 134 of the color separation lens array 130, the green light is directly under the fourth region 134. It is condensed in the center of the fourth light sensing cell 114. In other words, in one green pixel G, green light from the first region 131 or the fourth region 134 corresponding to the green pixel G, the first region 131 or the fourth region 134 The green light coming from the two second regions 132 and the two third regions 113 adjacent to each other in the horizontal and vertical directions is incident.

Accordingly, as shown in FIG. 14D, the color separation lens array 130 includes a plurality of micro lenses ML2 arranged around the first and fourth light sensing cells 111 and 114 for green light. It can play an equivalent role to an array. Since each of the equivalent micro lenses ML2 is larger than the first photo-sensing cell 111 or the fourth photo-sensing cell 114 corresponding thereto, the first photo-sensing cell 111 and the fourth photo-sensing cell 114 ), as well as green light incident on the other areas surrounding the first and fourth photo-sensing cells 111 and 114, as well as the first photo-sensing cell 111 and the fourth photo-sensing cell. It can be condensed at (114). For example, each micro-lens ML2 is about twice as large as the first light-sensing cell 111 or the fourth light-sensing cell 114 corresponding thereto, and the first light-sensing cell 111 and the corresponding 4 It may be arranged to be in contact with the light sensing cell 114 in a diagonal direction.

15A and 15B are diagrams for computational simulation of the phase distribution of red light passing through the color separation lens array and the focusing distribution of red light in an opposing light sensing cell, and FIG. 15C is a diagram illustrating a color separation lens array corresponding to a red pixel. The traveling direction of the red light incident on the region 3 and its surroundings is exemplarily shown, and FIG. 15D exemplarily shows a microlens array that acts equivalently to the color separation lens array for the red pixel R. FIG.

Looking at the phase distribution illustrated in FIG. 15A, the phase at the center of the region corresponding to the red pixel R is approximately 2π, and the phase at the center of the region corresponding to the adjacent green pixel G is approximately π. Value, and the phase at the center of the area corresponding to the blue pixel B in the diagonal direction is approximately smaller than π (eg, about 0.2π to 0.7π). This phase distribution may represent a focusing distribution of red light as shown in FIG. 15B. The red light is condensed in the area corresponding to the red pixel R, and the red light hardly reaches the area corresponding to the other pixels.

As a result, the third region 133 corresponding to the red pixel R and the light incident thereto pass through the color separation lens array 130 and then proceed as shown in FIG. 15C. For example, of incident light incident on some of the third area 133 and other areas surrounding the third area 133 of the color separation lens array 130, the red light is the third area directly under the third area 133. It is condensed in the center of the light sensing cell 113. In other words, one red pixel R includes red light coming from the third region 133 corresponding to the red pixel R, and two fourth regions 134 adjacent to the third region 133 in the horizontal direction. Red light coming from, red light coming from two first areas 131 adjacent to the third area 133 in the vertical direction, and red light coming from four second areas 132 adjacent to the third area 133 in a diagonal direction. Red light enters.

Accordingly, as shown in FIG. 15D, the color separation lens array 130 may play a role equivalent to an array of a plurality of micro lenses ML3 arranged around the third light sensing cell 113 for red light. . Since each equivalent microlens ML3 is larger than the corresponding third light sensing cell 113, not only the red light incident on the region of the third light sensing cell 113 but also the third light sensing cell 113 Red light incident to another surrounding area may also be condensed to the third light sensing cell 113. For example, each microlens ML3 is about 4 times larger than the corresponding third light sensing cell 113, and the four sides of each microlens ML3 are parallel to the four sides of the third light sensing cell 113. can do.

13C, 13D, 14C, 14D, 15C, and 15D to express differently, among the incident light incident on the first region 131 of the color separation lens array 130, green light is The first light sensing cell 111 corresponding to the first region 131 proceeds toward the center, and the blue light is applied to the second light sensing cell around the first light sensing cell 111 corresponding to the first region 131. The red light travels toward the central portion of 112 ), and the red light proceeds toward the central portion of the third optical sensing cell 113 around the first optical sensing cell 111 corresponding to the first region 131. In addition, among the incident light incident on the second region 132 of the color separation lens array 130, the blue light proceeds toward the center of the second light sensing cell 112 corresponding to the second region 132, and the green light is The second light-sensing cell 111 and the fourth light-sensing cell 114 around the second light-sensing cell 112 corresponding to the second area 132 are directed toward the center of the second area 132, and the red light is transmitted to the second area 132 It proceeds toward the center of the third light-sensing cell 113 around the second light-sensing cell 112 corresponding to ). Similarly, among the incident light incident on the third area 133 of the color separation lens array 130, the red light proceeds toward the center of the third light sensing cell 113 corresponding to the third area 133, and the green light is The first light sensing cell 111 and the fourth light sensing cell 114 around the third light sensing cell 113 corresponding to the third region 133 are directed toward the center of the third region 133, and the blue light is transmitted to the third region 133. ), the second light sensing cell 112 around the third light sensing cell 113 corresponding to ). Finally, among the incident light incident on the fourth region 134 of the color separation lens array 130, the green light proceeds toward the center of the fourth light sensing cell 114 corresponding to the fourth region 134, and the blue light Silver proceeds toward the center of the second light sensing cell 112 around the fourth light sensing cell 114 corresponding to the fourth region 134, and the red light senses the fourth light corresponding to the fourth region 134. It proceeds toward the center of the third light sensing cell 113 around the cell 114.

Such color separation and light collection may be performed more effectively by appropriately setting the thickness of the spacer layer 120. For example, when the theoretical thickness _{of the spacer layer 120 is the refractive index of the spacer layer 120 with respect to the wavelength of h t} and λ ₀ is n, and the pitch of the photosensitive cell is p, the following equation (1) may be satisfied. I can.

_{Here, the theoretical thickness h t} of the spacer layer 120 is a focal point at which light having a wavelength of λ ₀ is condensed on the upper surface of the light sensing cells 111, 112, 113 and 114 by the color separation lens array 130. Can mean distance. In other words, _{light having a wavelength of λ 0} may pass through the color separation lens array 130 and be focused at a distance _{h t} from the lower surface of the color separation lens array 130.

As described in Equation 1, the theoretical thickness h _t of the spacer layer 120 varies depending on the pitch (p) of the photosensitive cells 111, 112, 113, 114 and the refractive index (n) of the spacer layer 120 I can. For example, the center wavelength (λ ₀ ) of the visible light band is 540 nm, the pitch (p) of the light sensing cells 111, 112, 113, 114 is 0.8 μm, and the spacer layer 120 has a wavelength of 540 nm. Assuming that the refractive index (n) is 1.46, the theoretical thickness h _t of the spacer layer 120, that is, the distance between the lower surface of the color separation lens array 130 and the upper surface of the sensor substrate 110 may be about 1.64 μm. have. However, the actual thickness of the spacer layer 120 need not be limited only to the _{theoretical thickness (h t) described in Equation (1).} For example, the actual thickness of the spacer layer 120 may be selected within a predetermined range based on _{the theoretical thickness h t} of Equation 1 in consideration of the efficiency of the color separation lens array 130.

16A to 16E show the color separation lens array 130 according to the distance between the color separation lens array 130 and the sensor substrate 110 when the pitch of the photosensitive cells 111, 112, 113, and 114 is 0.7 μm. ) Is a graph showing the change in efficiency. 16A is a color separation lens for blue light incident on the second light sensing cell 112 from the first to fourth regions 131, 132, 133, and 134 constituting the unit pattern array of the color separation lens array 130 It shows the light-converging efficiency of the array 130, and FIG. 16B shows the first to fourth regions 131, 132, 133, and 134 constituting the unit pattern array, and the first photo-sensing cell 111 and the fourth photo-sensing cell ( 114) shows the condensing efficiency of the color separation lens array 130 for green light, and FIG. 16C shows the third light detection from the first to fourth regions 131, 132, 133, and 134 constituting the unit pattern array. It shows the condensing efficiency of the color separation lens array 130 for red light incident on the cell 113.

In the case of FIGS. 16A and 16C, since four regions are arranged for one light sensing cell, the theoretical maximum value is 4. In the case of FIG. 16B, since four regions are arranged for two light sensing cells, the theoretical maximum value is 2. In the graphs of FIGS. 16A to 16C, the distance of the color separation lens array 130 having the highest light collection efficiency becomes a theoretical thickness h _t that satisfies Equation 1. As shown in FIGS. 16A to 16C, the theoretical thickness h _t varies slightly depending on the wavelength.

16D is a graph showing an example of a change in efficiency of a color separation lens array in consideration of a sensitivity characteristic of a human eye to visible light. For example, the human eye is typically the most sensitive to green light and the least sensitive to blue light. Therefore, the graph of FIG. 16D can be obtained by assigning the lowest weight to the graph of FIG. 16A, giving the graph of FIG. 16C a higher weight than that of blue light, and giving the highest weight to FIG. 16B and then averaging the summed values. . 16E is a graph showing the results of normalizing the graph of FIG. 16D.

Referring to the graphs of FIGS. 16D and 16E, when the pitch of the photosensitive cells 111, 112, 113, and 114 is 0.7 μm, the color separation lens array for the entire visible light considering the sensitivity characteristics of the human eye ( 130) is the highest at a distance of about 1.2 μm. Further, the efficiency of the color separation lens array 130 becomes about 80% of the maximum efficiency at a distance of about 0.5 μm, and about 95% of the maximum efficiency at a distance of about 1.9 μm.

17A to 17E show the color separation lens array 130 according to the distance between the color separation lens array 130 and the sensor substrate 110 when the pitch of the light sensing cells 111, 112, 113, and 114 is 0.8 μm. ) Is a graph showing the change in efficiency. 17A to 17E, when the pitch of the photosensitive cells 111, 112, 113, and 114 is 0.8 μm, the color separation lens array 130 for the entire visible light considering the sensitivity characteristics of the human eye The efficiency of is highest at a distance of about 1.64 μm. In addition, the efficiency of the color separation lens array 130 becomes about 85% of the maximum efficiency at a distance of about 0.8 μm, and about 93% of the maximum efficiency at a distance of about 2.5 μm.

18A to 18E show the color separation lens array 130 according to the distance between the color separation lens array 130 and the sensor substrate 110 when the pitch of the photosensitive cells 111, 112, 113, and 114 is 1.0 μm. ) Is a graph showing the change in efficiency. 18A to 18E, when the pitch of the photosensitive cells 111, 112, 113, and 114 is 1.0 μm, the color separation lens array 130 for the entire visible light considering the sensitivity characteristics of the human eye The efficiency of is highest at a distance of about 2.6 μm. In addition, the efficiency of the color separation lens array 130 becomes about 87% of the maximum efficiency at a distance of about 1.6 μm, and about 94% of the maximum efficiency at a distance of about 3.6 μm.

As a result, even if the actual thickness (h) of the spacer layer 120 _{is larger or smaller than the theoretical thickness (h t} ) of Equation 1 by the pitch p of the photosensitive cells 111, 112, 113, 114, It can be seen that the color separation lens array 130 has a high efficiency of 80% or more, 90% or more, or 95% or more of the maximum efficiency. Considering the above result, the actual thickness (h) of the spacer layer 120 is h _t - may be chosen within the range of _{p ≤ h ≤ h t + p} .

Since the above-described color separation lens array 130 can diverge by wavelength and condense the branched light to a specific area without absorbing or blocking incident light, it is possible to improve the light utilization efficiency of the image sensor. In addition, since the color separation lens array 130 has improved color separation performance, an image sensor employing the color separation lens array 130 may have excellent color purity. In addition, the image sensor employing the color separation lens array 130 can maintain the Bayer pattern method generally adopted in the image sensor, and thus can utilize the same image processing algorithm as the existing pixel structure. Moreover, since the color separation lens array 130 can also serve as a lens for condensing incident light, an image sensor employing the color separation lens array 130 provides a separate microlens for condensing light to each pixel. I don't need it.

19 is a graph exemplarily showing spectral distributions of light incident on a blue pixel, a green pixel, and a red pixel of the image sensor illustrated in FIGS. 8A and 8B. The blue pixel may correspond to the second photo-sensing cell 112, the green pixel may correspond to the first photo-sensing cell 111 and the fourth photo-sensing cell 114, and the red pixel may correspond to the third photo-sensing cell ( 113).

In FIG. 19, thick lines indicate spectral distributions of light incident on a blue pixel, a green pixel, and a red pixel, respectively, when the color separation lens array 130 is used. The thick solid line is the spectral distribution of light incident on the blue pixel, the thick dotted line is the spectral distribution of light incident on the green pixel, and the thick dashed line is the spectral distribution of light incident on the red pixel. For comparison, when a general color filter is used instead of the color separation lens array 130, spectral distributions of light incident on a blue pixel, a green pixel, and a red pixel are indicated by thin lines in FIG. 19. The thin solid line is the spectral distribution of light incident on the blue pixel, the thin dotted line is the spectral distribution of light incident on the green pixel, and the thin chain line is the spectral distribution of light incident on the red pixel. Referring to FIG. 19, it can be seen that the intensity of light indicated by a thick line is greater than the intensity of light indicated by a thin line. Accordingly, the use of the color separation lens array 130 may improve light utilization efficiency of the image sensor 1000.

The pattern of the color separation lens array 130 that satisfies the above-described phase distribution and performance can be automatically designed through various computer simulations. For example, using a nature-inspired algorithm such as genetic algorithm, particle swarm optimization algorithm, ant colony optimization, or adjoint optimization ) The pattern of the first to fourth regions 131, 132, 133, and 134 may be optimized through an algorithm-based reverse engineering method.

For the design of the color separation lens array 130, the first to fourth regions 131 and 132, while evaluating the performance of a plurality of candidate color separation lens arrays using evaluation factors such as color separation spectrum, light efficiency, signal-to-noise ratio, etc. The first to fourth patterns of 133 and 134 may be optimized. For example, after determining a target numerical value for each evaluation element in advance, the first to fourth regions 131, 132, 133 are minimized in a manner that minimizes the sum of the differences between the target numerical values for the plurality of evaluation elements. , 134) of the first to fourth patterns may be optimized. Alternatively, performance may be indexed for each evaluation element, and first to fourth patterns of the first to fourth regions 131, 132, 133 and 134 may be optimized so that a value representing the performance is maximized.

The color separation lens array 130 shown in FIG. 4 is only an example, and the size, thickness, and color separation lens of the first to fourth regions 131, 132, 133, and 134 of the color separation lens array 130 According to the color characteristics of the image sensor to which the array 130 is applied, the pixel pitch, the distance between the color separation lens array 130 and the image sensor, the incident angle of incident light, etc., various types of color separation lens array 130 ) Can be obtained. For example, FIG. 20 is a plan view exemplarily showing the shape of a unit pattern array of a color separation lens array according to another embodiment that can be applied to a Bayer pattern type image sensor, and FIG. 21 is a view showing a Bayer pattern type image sensor. It is a plan view exemplarily showing a shape of a unit pattern array of a color separation lens array according to another embodiment that can be applied.

Each of the first to fourth regions 131, 132, 133, and 134 shown in FIG. 4 is optimized in a digitized binary form in a 14×14 rectangular arrangement, and the first to fourth regions 131 shown in FIG. 20 , 132, 133, and 134) are each optimized in a digitized binary form in a 16×16 rectangular array. Accordingly, the unit pattern array of the color separation lens array 130 shown in FIG. 4 has a shape consisting of a 28×28 rectangular array, and the unit pattern array of the color separation lens shown in FIG. 20 is a 32×32 rectangular array. It has a form consisting of. In this case, the shape of the vertical cross section of the first to fourth regions 131, 132, 133, and 134 shown in FIGS. 5 and 6 is as the AA' line moves along the Y direction or the BB' line moves in the X direction. As it moves along, it changes discontinuously.

Alternatively, each of the first to fourth regions 131, 132, 133, and 134 shown in FIG. 21 may be optimized in the form of a continuous curve that is not digitized. In this case, the shape of the vertical cross section of the first to fourth regions 131, 132, 133, and 134 shown in FIGS. 5 and 6 is as the AA' line moves along the Y direction or the BB' line moves in the X direction. It changes continuously as it moves along.

22A and 22B are schematic cross-sectional views illustrating a pixel array of an image sensor according to another exemplary embodiment, respectively. 22A and 22B, the pixel array 1100a includes a sensor substrate 110 including a plurality of light sensing cells 111, 112, 113, and 114 that convert the intensity of incident light into an electrical signal, and a sensor substrate. (110) A color filter layer 105 disposed above, a spacer layer 120 disposed on the color filter layer 105, and a color separation lens array 130 disposed on the spacer layer 120.

The color filter layer 105 includes a first color filter CF1 disposed on the first photo-sensing cell 111 and the fourth photo-sensing cell 114, and a second color filter disposed on the second photo-sensing cell 112. CF2), and a third color filter CF3 disposed on the third light sensing cell 113. For example, the first color filter CF1 is a green color filter that transmits only green light from the incident light and absorbs the rest, the second color filter CF2 is a blue color filter that transmits only blue light from the incident light and absorbs the rest, and the third color filter. The color filter CF3 may be a red color filter that transmits only red light and absorbs the rest of incident light. By using these color filters CF1, CF2, and CF3, the image sensor 1000 can achieve higher color purity. Since light, which has already been color-separated to a considerable extent by the color separation lens array 130, enters the color filters CF1, CF2, and CF3, respectively, the light loss due to the color filter layer 105 is not large. If color separation by the color separation lens array 130 is sufficient, the color filter layer 105 may be omitted, and only some of the first to third color filters CF1, CF2, and CF3 may be omitted.

The specific patterns of the color separation lens array 130 described so far are merely exemplary, and various modifications thereof are possible. For example, according to different pattern shapes of the first to fourth regions 131, 132, 133, and 134 of the color separation lens array 130, wavelength bands other than visible light may be separated. Also, the number of color separation patterns constituting the unit pattern array of the color separation lens array 130 may be variously changed according to an application example of the color separation lens array 130. The pixel arrangement of the image sensor has been described by exemplifying the Bayer pattern, but is not limited thereto, and may also be applied to the pixel arrangement shown in FIGS. 2B and 2C. A pattern suitable for this pixel arrangement may be determined by adopting regions of the color separation lens array 130 and using the above-described optimization method for each region.

23 is a plan view illustrating a color separation lens array according to another exemplary embodiment. Referring to FIG. 23, the color separation lens array 140 may include a plurality of two-dimensional array of unit patterns indicated by thick lines. Each unit pattern array may be arranged in a 2×2 shape including the first region 141, the second region 142, the third region 143, and the fourth region 144. When looking at the overall configuration of the color separation lens array 140, the first regions 141 and the second regions 142 are alternately arranged in the horizontal direction in one row, and the third region in the other row. The regions 143 and the fourth regions 144 are alternately arranged along the horizontal direction. In addition, the first region 141 and the third region 143 are alternately arranged along the vertical direction in one column, and the second region 142 and the fourth region 144 are arranged in another column. They are arranged alternately along the longitudinal direction.

In addition, the color separation lens array 140 may further include a plurality of first to fourth regions 141, 142, 143 and 144 that do not belong to any unit pattern array. The first to fourth regions 141, 142, 143 and 144 that do not belong to any unit pattern array may be arranged along the edge of the color separation lens array 140. In other words, a plurality of second regions 142 and a plurality of fourth regions 144 constituting one column are additionally arranged on the left edge of the color separation lens array 140, and one column is formed on the right edge. A plurality of first regions 141 and a plurality of third regions 143 are additionally arranged, and a plurality of third regions 143 and a plurality of fourth regions 144 constituting one row at the upper edge. ) May be additionally arranged, and a plurality of first regions 141 and a plurality of second regions 142 constituting one row may be additionally arranged at the lower edge.

FIG. 24 is a vertical cross-section of the color separation lens array 140 shown in FIG. 23 taken along a line C-C'. Referring to FIG. 24, the color separation lens array 140 is disposed to protrude in a horizontal direction with respect to the edge of the sensor substrate 110 and does not face any light sensing cells of the sensor substrate 110 in the vertical direction. A first region 141 and a plurality of second regions 142 may be included. Although not all shown in FIG. 24, in FIG. 23, the plurality of first to fourth regions 141, 142, 143, and 144 that do not belong to any unit pattern array are all in a horizontal direction with respect to the edge of the sensor substrate 110. It is arranged to protrude and does not face any light sensing cells in the vertical direction.

As described in FIGS. 13A to 13D, 14A to 14D, and 15A to 15D, the photosensitive cell is not only a region of the color separation lens array 140 corresponding to a vertically, but also a plurality of other regions around the region. It is also provided with light from the realms. Therefore, in the absence of the first to fourth regions 141, 142, 143, and 144 added along the edge of the color separation lens array 140, the light sensing cells arranged along the edge of the sensor substrate 110 The amount of incident light is reduced, and color purity may also decrease. By further arranging the first to fourth regions 141, 142, 143, and 144 along the edge of the color separation lens array 140, the sensor substrate ( Light may be provided in the same manner as the light sensing cells arranged on the inside of 110).

Since the image sensor according to the above-described embodiments hardly loses light due to the color filter, a sufficient amount of light can be provided to the pixel even if the size of the pixel is reduced. Therefore, it is possible to manufacture an ultra-high resolution, ultra-small, high-sensitivity image sensor having hundreds of millions of pixels or more. Such an ultra-high resolution, ultra-small, high-sensitivity image sensor may be employed in various high-performance optical devices or high-performance electronic devices. For example, such electronic devices include, for example, smart phones, mobile phones, mobile phones, personal digital assistants (PDAs), laptops, PCs, various portable devices, home appliances, security cameras, medical cameras, and automobiles. , Internet of Things (IoT), other mobile or non-mobile computing devices, but is not limited thereto.

25 is a schematic block diagram of an electronic device including an image sensor according to embodiments. The electronic device includes an image sensor 1000, a processor 2200, a memory 2300, a display 2400, and a bus 2500. The image sensor 1000 acquires image information on an external subject under the control of the processor 2200 and provides it to the processor 2200. The processor 2200 may store the image information provided from the image sensor 1000 in the memory 2300 through the bus 2500, and output the image information stored in the memory 2300 to the display 2400 to be displayed to the user. have. Also, the processor 2200 may perform various image processing on image information provided from the image sensor 1000.

26 to 36 show various examples of electronic devices to which an image sensor according to embodiments is applied.

The image sensor according to the embodiments may be applied to various multimedia devices having an image capturing function. For example, the image sensor may be applied to the camera 2000 shown in FIG. 26. The camera 2000 may be a digital camera or a digital camcorder.

Referring to FIG. 27, the camera 2000 may include an imaging unit 2100, an image sensor 1000, and a processor 2200.

The imaging unit 2100 forms an optical image by focusing light reflected from the subject OBJ. The imaging unit 2100 may include an objective lens 2010, a lens driving unit 2120, a diaphragm 2130, and a diaphragm driving unit 2140. In FIG. 27, only one lens is representatively displayed for convenience, but the objective lens 2010 may actually include a plurality of lenses having different sizes and shapes. The lens driver 2120 may communicate information on focus detection with the processor 2200 and may adjust the position of the objective lens 2010 according to a control signal provided from the processor 2200. The lens driver 1120 may move the objective lens 2010 to adjust the distance between the objective lens 2010 and the object OBJ, or may adjust the positions of individual lenses in the objective lens 2010. The focus on the subject OBJ may be adjusted by the lens driver 2120 driving the objective lens 2010. The camera 2000 may have an auto focus function.

The iris driver 2140 may communicate information on the amount of light with the processor 2200 and may adjust the iris 2130 according to a control signal provided from the processor 2200. For example, the aperture driver 2140 may increase or decrease the aperture of the aperture 2130 according to the amount of light entering the camera 2000 through the objective lens 2010, and the aperture 2130 may be opened. You can adjust the time.

The image sensor 1000 may generate an electrical image signal based on the intensity of incident light. The image sensor 1000 may include a pixel array 1100, a timing controller 1010, and an output circuit 1030. Although not shown in FIG. 27, the image sensor 1000 may further include a row decoder shown in FIG. 1. Light transmitted through the objective lens 2010 and the aperture 2130 may form an image of the object OBJ on the light-receiving surface of the pixel array 1100. The pixel array 1100 may be a CCD or CMOS that converts optical signals into electrical signals. The pixel array 1100 may include additional pixels for performing an AF function or a distance measurement function. Also, the pixel array 1100 may include the above-described color separation lens array.

The processor 2200 may control the overall operation of the camera 2000 and may have an image processing function. For example, the processor 2200 may provide a control signal for the operation of each component to the lens driver 2120, the aperture driver 2140, the timing controller 1010, and the like.

The image sensor according to the embodiments is a mobile phone or smart phone 3000 shown in FIG. 28, a tablet or smart tablet 3100 shown in FIG. 29, a notebook computer 3200 shown in FIG. 30, and shown in FIG. 31 It can be applied to the TV or smart television (3300). For example, the smart phone 3000 or the smart tablet 3100 may include a plurality of high-resolution cameras each equipped with a high-resolution image sensor. Using high-resolution cameras, depth information of subjects in an image can be extracted, out-focusing of an image can be adjusted, or subjects in an image can be automatically identified.

In addition, the image sensor can be applied to the smart refrigerator 3400 shown in FIG. 32, the security camera 3500 shown in FIG. 33, the robot 3600 shown in FIG. 34, the medical camera 3700 shown in FIG. 35, and the like. have. For example, the smart refrigerator 3400 may automatically recognize food in the refrigerator using an image sensor, and inform the user of the existence of a specific food, the type of food stocked or released, and the like to the user through the smartphone. The security camera 3500 may provide an ultra-high resolution image, and may use high sensitivity to recognize an object or person in the image even in a dark environment. The robot 3600 may be input at a disaster or industrial site that cannot be directly accessed by humans to provide a high-resolution image. The medical camera 3700 can provide a high-resolution image for diagnosis or surgery, and can dynamically adjust a field of view.

Also, the image sensor may be applied to the vehicle 3800 as shown in FIG. 36. The vehicle 3800 may include a plurality of vehicle cameras 3810, 3820, 3830, and 3840 arranged at various locations, and each vehicle camera 3810, 3820, 3830, and 3840 uses an image sensor according to an embodiment. Can include. The vehicle 3800 may provide a variety of information about the interior or surroundings of the vehicle 3800 to the driver using a plurality of vehicle cameras 3810, 3820, 3830, and 3840, and automatically recognizes objects or people in the image. It can provide information necessary for autonomous driving.

Although the image sensor having the above-described color separation lens array and the electronic device including the same have been described with reference to the embodiment shown in the drawings, this is only exemplary, and those of ordinary skill in the art have various It will be appreciated that variations and other equivalent embodiments are possible. Therefore, the disclosed embodiments should be considered from an illustrative point of view rather than a limiting point of view. The scope of the rights is indicated in the claims rather than the above description, and all differences within the scope equivalent thereto should be construed as being included in the scope of the rights.

105.....color filter
110.....sensor board
111, 112, 113, 114.....light sensing cell
120.....spacer layer
130, 140.....color-separated lens array
131, 141.....the first area
132, 142.....Second area
133, 143.....3rd area
134, 144.....4th area
1000.....image sensor
1010.....Timing controller
1020.....low decoder
1030.....output circuit
1100.....pixel array

Claims (25)

A sensor substrate including a first light sensing cell and a second light sensing cell for sensing light;
A transparent spacer layer disposed on the sensor substrate; And
Including; a color separation lens array disposed on the spacer layer,
The color separation lens array is disposed to face the first light sensing cell in a vertical direction and is disposed to face the first region having a first pattern and the second light sensing cell in a vertical direction. Comprising a second region having a different second pattern,
The first pattern and the second pattern separate light of a first wavelength and light of a second wavelength different from each other included in the incident light with respect to the incident light incident on the color separation lens array, and the first light sensing cell An image sensor for condensing light of a first wavelength to and condensing light of a second wavelength to the second light sensing cell. The method of claim 1,
The spacer layer has a thickness corresponding to a focal length of the color separation lens array at a center wavelength of a wavelength band of incident light color-separated by the color separation lens array. The method of claim 1,
When the theoretical thickness of the spacer layer is h _t , the pitch of each photosensitive cell is p, the refractive index of the spacer layer is n, and the center wavelength of the wavelength band of incident light color-separated by the color separation lens array is λ ₀ . , The theoretical thickness of the spacer layer is

ego,
The actual thickness h of the spacer layer is h _t -p ≤ h ≤ h _t + p. The method of claim 1,
In the first pattern and the second pattern, at a position immediately after passing through the color separation lens array, light of a first wavelength forms a phase distribution of 2Nπ at a position corresponding to the center of the first light sensing cell. 2 An image sensor that forms a phase distribution of (2N-1)π at a position corresponding to the center of the light sensing cell, where N is an integer greater than 0. The method of claim 4,
The first pattern and the second pattern have a phase distribution of (2M-1)π at a position immediately after passing through the color separation lens array and at a position corresponding to the center of the first light sensing cell. And to form a phase distribution of 2Mπ at a position corresponding to the center of the second light sensing cell, and M is an integer greater than 0. The method of claim 1,
The first region includes a first dielectric having a first refractive index and forming a first pattern, and a second dielectric having a second refractive index less than the first refractive index and filled between the first dielectrics,
The image sensor, wherein the first pattern is formed so that the first dielectric is present in any vertical cross section of the first region. The method of claim 1,
The second region includes a first dielectric having a first refractive index and forming a second pattern, and a second dielectric having a second refractive index less than the first refractive index and filled between the first dielectrics,
The image sensor, wherein a second pattern is formed such that the first dielectric is present in any vertical cross section of the second region. The method of claim 1,
The sensor substrate further includes a third light sensing cell and a fourth light sensing cell,
The color separation lens array is disposed to face the third light sensing cell in a vertical direction and has a third region having a third pattern different from the first pattern and the second pattern, and the fourth light sensing cell in a vertical direction. The image sensor, further comprising a fourth region disposed facing the fourth pattern and having a fourth pattern different from the first pattern to the third pattern. The method of claim 8,
The third area is disposed adjacent to the first area and disposed in a diagonal direction of the second area, and the fourth area is disposed adjacent to the second area and disposed in a diagonal direction of the first area,
The first to fourth patterns separate light of different first wavelength, light of a second wavelength, and light of a third wavelength included in the incident light with respect to the incident light incident on the color separation lens array. , Light of a first wavelength is condensed to the first and fourth light sensing cells, light of a second wavelength is condensed to the second light sensing cell, and light of a third wavelength is condensed to the third light sensing cell Let's go, the image sensor. The method of claim 9,
The first to fourth patterns have a phase of 2Nπ at a position immediately after passing through the color separation lens array and at a position corresponding to the center of the first light sensing cell and the fourth light sensing cell. The image sensor, wherein a distribution is formed and a phase distribution of (2N-1)π is formed at positions corresponding to the centers of the second and third light sensing cells, and N is an integer greater than 0. The method of claim 10,
In the first to fourth patterns, at a position immediately after passing through the color separation lens array, light of a second wavelength is at a position corresponding to the center of the first photosensitive cell and the center of the fourth photosensitive cell. A phase distribution of (2M-1)π is formed and a phase distribution of 2Mπ is formed at a position corresponding to the center of the second photosensitive cell, and (2M-2) at a position corresponding to the center of the third photosensitive cell. An image sensor, wherein a phase distribution greater than π and less than (2M-1)π is formed, and M is an integer greater than 0. The method of claim 11,
In the first to fourth patterns, at a position immediately after passing through the color separation lens array, light of a third wavelength is at a position corresponding to the center of the first photosensitive cell and the center of the fourth photosensitive cell. A phase distribution of (2L-1)π is formed, and a phase distribution larger than (2L-2)π and smaller than (2L-1)π is formed at a position corresponding to the center of the second light sensing cell, and the third light An image sensor, in which a phase distribution of 2Lπ is formed at a position corresponding to the center of the sensing cell, and L is an integer greater than 0. The method of claim 9,
In the first to fourth patterns, among incident light incident on the first region of the color separation lens array, the light of the first wavelength proceeds toward the center of the first light sensing cell corresponding to the first region, The light of the second wavelength advances toward the center of the second light-sensing cell around the first light-sensing cell corresponding to the first area, and the light of the third wavelength is a first light-sensing cell corresponding to the first area. An image sensor that advances toward the center of the surrounding third light sensing cell. The method of claim 9,
In the first to fourth patterns, among incident light incident on the second region of the color separation lens array, light of a second wavelength proceeds toward the center of the second light sensing cell corresponding to the second region, The light of the first wavelength proceeds toward the center of the first and fourth light sensing cells around the second light sensing cell corresponding to the second region, and the light of the third wavelength corresponds to the second region. An image sensor that advances toward the center of the third light sensing cell around the second light sensing cell. The method of claim 9,
In the first to fourth patterns, among incident light incident on a third area of the color separation lens array, light of a third wavelength proceeds toward the center of the third light sensing cell corresponding to the third area, The light of the first wavelength advances toward the center of the first and fourth light sensing cells around the third light sensing cell corresponding to the third region, and the light of the second wavelength corresponds to the third region. An image sensor that advances toward the center of the second light sensing cell around the third light sensing cell. The method of claim 9,
In the first to fourth patterns, among incident light incident on a fourth region of the color separation lens array, light of a first wavelength proceeds toward a central portion of a fourth light sensing cell corresponding to the fourth region, The light of the second wavelength advances toward the center of the second light-sensing cell around the fourth light-sensing cell corresponding to the fourth area, and the light of the third wavelength is a fourth light-sensing cell corresponding to the fourth area. An image sensor that advances toward the center of the surrounding third light sensing cell. The method of claim 9,
The image sensor, wherein the light of the first wavelength is green light, the light of the second wavelength is blue light, and the light of the third wavelength is red light. The method of claim 17,
The first pattern and the fourth pattern are two-way symmetric, the second pattern and the third pattern are four-way symmetric, and the fourth pattern has a shape rotated 90 degrees with respect to the first pattern. The method of claim 9,
The color separation lens array includes a plurality of unit pattern arrays including a first region, a second region, a third region, and a fourth region adjacent to each other, and the plurality of unit pattern arrays are arranged in a two-dimensional manner. The image sensor. The method of claim 9,
The color separation lens array is disposed to protrude from the edge of the sensor substrate, and a plurality of first regions, a plurality of second regions, and a plurality of third regions that do not face any light sensing cells of the sensor substrate in a vertical direction , And a plurality of fourth regions. The method of claim 1,
An image sensor disposed between the sensor substrate and the spacer layer and further comprising a color filter layer including a plurality of color filters. A sensor substrate including first to fourth light sensing cells for sensing light;
A transparent spacer layer disposed on the sensor substrate; And
Including; a color separation lens array disposed on the spacer layer,
The color separation lens array is disposed to face the first light sensing cell in a vertical direction, a first region having a first pattern, and is disposed to face the second light sensing cell in a vertical direction, and the first pattern and A second region having a different second pattern, a third region disposed to face the third light sensing cell along a vertical direction and having a third pattern different from the first pattern and the second pattern, and the third region along the vertical direction. It is disposed facing the fourth light sensing cell and includes a fourth region having a fourth pattern different from the first pattern to the third pattern,
The third area is disposed adjacent to the first area and disposed in a diagonal direction of the second area, and the fourth area is disposed adjacent to the second area and disposed in a diagonal direction of the first area,
The first pattern and the fourth pattern are two-way symmetric, the second pattern and the third pattern are four-way symmetric, and the fourth pattern has a shape rotated 90 degrees with respect to the first pattern. The method of claim 22,
The first to fourth patterns separate light of different first wavelength, light of a second wavelength, and light of a third wavelength included in the incident light with respect to the incident light incident on the color separation lens array. , Light of a first wavelength is condensed to the first and fourth light sensing cells, light of a second wavelength is condensed to the second light sensing cell, and light of a third wavelength is condensed to the third light sensing cell Let's go, the image sensor. An objective lens that focuses light reflected from an object to form an optical image; And
An image pickup apparatus comprising: the image sensor according to any one of claims 1 to 23, which converts the optical image formed by the objective lens into an electrical image signal. An electronic device comprising the imaging device according to claim 24.

Images