Image sensor and electronic device including the same

Abstract

The invention discloses an image sensor and an electronic device including the same. The image sensor includes: a sensor substrate including a plurality of pixels sensing incident light; the nano optical micro lens array comprises a plurality of nano optical micro lenses corresponding to the plurality of pixels respectively; and a color filter array disposed between the sensor substrate and the nano-optical microlens array, and including a plurality of color filters. Each of the plurality of nano-optical microlenses includes a plurality of nanostructures for converging incident light onto a corresponding pixel, and the fill factor represents a ratio of an area of a nanostructure arranged within a reference circle among a plurality of nanostructures included in one of the plurality of nanooptical microlenses to an entire area of the plurality of nanostructures included in the one of the plurality of nanooptical microlenses, and the reference circle has a pixel size corresponding to one nano-optical microlens as a diameter, the fill factor being greater than or equal to 95%.

Description

[0001] Cross - reference to related applications

[0002] This application claims priority based on and claims the benefit of Korean Patent Application No. 10 - 2023 - 0168239, filed with the Korean Intellectual Property Office on November 28, 2023, the disclosure of which is incorporated herein by reference in its entirety. Technical field

[0003] An apparatus and method according to an embodiment of the present disclosure relate to an image sensor and an electronic device including the image sensor. Background art

[0004] As the resolution of an image sensor increases, the size of unit pixels in the image sensor is decreasing. To improve low - light sensitivity and resolution, a pixel array having multiple monochromatic channels may be used.

[0005] According to this trend, micro - lens configurations have been studied, which improve the autofocus (AF) function of the image sensor and reduce the performance degradation of the image sensor according to the change in the principal ray angle. Summary of the invention

[0006] One or more embodiments provide an image sensor having a nano - optical microlens array, which can improve the autofocus (AF) function and crosstalk reduction performance.

[0007] According to an aspect of the present disclosure, an image sensor may include: a sensor substrate including a plurality of pixels configured to sense incident light; a nano - optical microlens array including a plurality of nano - optical microlenses respectively corresponding to the plurality of pixels; and a color filter array disposed between the sensor substrate and the nano - optical microlens array and including a plurality of color filters, wherein each of the plurality of nano - optical microlenses may include a plurality of nanostructures for converging incident light onto a corresponding pixel, and the fill factor represents the ratio of the area of the nanostructures arranged within a reference circle among the plurality of nanostructures included in one nano - optical microlens to the entire area of the plurality of nanostructures included in the one nano - optical microlens, and the reference circle has a diameter equal to the size of the pixel corresponding to the one nano - optical microlens, and the fill factor is greater than or equal to 95%.

[0008] Among the plurality of nano - optical microlenses, the fill factor of the nano - optical microlens located at the center - most point of the nano - optical microlens array may be 100%.

[0009] Each of the plurality of pixels may include four photosensitive units arranged in a 2×2 pattern.

[0010] Multiple nanostructures can be arranged in a two-dimensional plane perpendicular to the direction in which the sensor substrate, color filter array, and nano-optical microlens array are arranged. When the multiple nanostructures are arranged in the form of an N×N matrix in the two-dimensional plane, one or more of the multiple nanostructures do not exist at four positions (1, 1), (1, N), (N, 1), and (N, N). N is an integer greater than or equal to 3.

[0011] Among the multiple nano-optical microlenses, the multiple nanostructures included in the nano-optical microlens located at the center of the nano-optical microlens array may not exist at the four positions (1, 1), (1, N), (N, 1), and (N, N) of the N×N matrix, and may occupy the remaining N 2 - 4 positions.

[0012] When the multiple nano-optical microlenses are divided into a center and a periphery according to their relative positions within the nano-optical microlens array, the multiple nanostructures included in one nano-optical microlens located at the periphery are arranged in a row or a column in an order of increasing size toward the center.

[0013] When the multiple nano-optical microlenses are divided into a center and a periphery according to their relative positions within the nano-optical microlens array, among the nano-optical microlenses belonging to the periphery, in two nano-optical microlenses having different azimuth angles defined in the two-dimensional plane, the positions where the nanostructures do not exist are different among the four positions (1, 1), (1, N), (N, 1), and (N, N).

[0014] When the multiple nano-optical microlenses are divided into a center and a periphery according to their relative positions within the nano-optical microlens array, among the nano-optical microlenses belonging to the periphery, in the nano-optical microlens having an azimuth angle of 0 degrees defined in the two-dimensional plane, the nanostructures do not exist at the positions (1, N) and (N, N).

[0015] When the multiple nano-optical microlenses are divided into a center and a periphery according to their relative positions within the nano-optical microlens array, among the nano-optical microlenses belonging to the periphery, in the nano-optical microlens having an azimuth angle of 90 degrees defined in the two-dimensional plane, the nanostructures do not exist at the positions (1, 1) and (1, N).

[0016] When the multiple nano-optical microlenses are divided into a center and a periphery according to their relative positions within the nano-optical microlens array, among the nano-optical microlenses belonging to the periphery, in the nano-optical microlens having an azimuth angle of 180 degrees defined in the two-dimensional plane, the nanostructures do not exist at the positions (1, 1) and (N, 1).

[0017] When multiple nano-optical microlenses are divided into a center and a periphery according to their relative positions within a nano-optical microlens array, among the nano-optical microlenses belonging to the periphery, in the nano-optical microlens having an azimuth angle defined in a two-dimensional plane of 270 degrees, nanostructures do not exist at positions (N, 1) and (N, N).

[0018] When multiple nano-optical microlenses are divided into a center and a periphery according to their relative positions within a nano-optical microlens array, the fill factor of the nano-optical microlenses at the center is greater than the fill factor of the nano-optical microlenses at the periphery.

[0019] The multiple nano-optical microlenses may include: a first nano-optical microlens facing a green filter; a second nano-optical microlens facing a blue filter; and a third nano-optical microlens facing a red filter.

[0020] The fill factor of the second nano-optical microlens is less than the fill factor of the first nano-optical microlens or the third nano-optical microlens.

[0021] The number of nanostructures included in the second nano-optical microlens is greater than the number of nanostructures included in the first nano-optical microlens or the third nano-optical microlens.

[0022] The multiple pixels may include first to fourth pixel groups arranged adjacent to each other in a 2×2 layout. The first to fourth pixel groups may each include four first to fourth pixels arranged adjacent to each other in a 2×2 layout. The multiple nano-optical microlenses may include four first to fourth nano-optical microlenses respectively corresponding to the four first to fourth pixels arranged adjacent to each other in a 2×2 layout. The color filter array may include a first green filter, a blue filter, a red filter, and a second green filter, and the first green filter, the blue filter, the red filter, and the second green filter respectively face the first to fourth pixel groups one-to-one.

[0023] The multiple pixels may include first to fourth pixels arranged adjacent to each other in a 2×2 layout. Each of the first to fourth pixels may include four photosensitive units arranged in a 2×2 layout. The multiple nano-optical microlenses may include first to fourth nano-optical microlenses respectively facing the first to fourth pixels. The color filter array may include a first green filter, a blue filter, a red filter, and a second green filter, and the first green filter, the blue filter, the red filter, and the second green filter may respectively face the first to fourth pixels one-to-one.

[0024] According to another aspect of the present disclosure, an electronic device may include: a lens assembly including one or more lenses for forming an optical image of an object; an image sensor configured to convert the optical image into an electrical signal; and a processor configured to process the electrical signal generated by the image sensor.

[0025] According to another aspect of the present disclosure, an image sensor may include: a sensor substrate including a plurality of pixels configured to sense incident light; a nano-optical microlens array including a plurality of nano-optical microlenses respectively corresponding to the plurality of pixels; and a color filter array disposed between the sensor substrate and the nano-optical microlens array and including a plurality of color filters, wherein each of the plurality of nano-optical microlenses may include a plurality of nanostructures for converging incident light onto a corresponding pixel, and when the plurality of nanostructures are arranged in the form of an N×N matrix in a two-dimensional plane, in the nano-optical microlens disposed at the center of the nano-optical microlens array, the plurality of nanostructures do not exist at four positions (1, 1), (1, N), (N, 1), and (N, N), and are disposed at the remaining N 2 -4 positions, and wherein N is an integer greater than or equal to 3.

[0026] According to another aspect of the present disclosure, an image sensor may include: a sensor substrate including pixels configured to convert light into an electrical signal; a nano-optical microlens array including nano-optical microlenses for focusing light onto the pixels; and a color filter array located between the sensor substrate and the nano-optical microlens array, wherein each of the nano-optical microlenses may include nanostructures arranged along the circumferences of two concentric circles having different diameters and positioned away from the pixel boundary lines and the center of the concentric circles. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] The above and other aspects, features, and advantages of certain embodiments of the present disclosure will become more apparent from the following description in conjunction with the accompanying drawings, in which:

[0028] Figure 1 is a block diagram of an image sensor according to an embodiment;

[0029] Figure 2A is a plan view showing the color arrangement of a pixel array in the image sensor; Figure 2B 、 Figure 2C and Figure 2D are schematic plan views respectively showing the sensor substrate, the color filter array, and the nano-optical microlens array included in the pixel array;

[0030] Figure 3A and Figure 3B are along Figure 2DCross-sectional view of a pixel array of an image sensor intercepted by line AA' and line BB';

[0031] Figure 4A and Figure 4B is a plan view showing a nano-optical microlens array according to Comparative Example 1 and Comparative Example 2;

[0032] Figure 5A and Figure 5B is a calculated simulation curve graph showing the spectrum of light sensed by an image sensor including nano-optical microlenses according to Comparative Example 1 and Comparative Example 2;

[0033] Figure 5C is a calculated simulation curve graph showing the spectrum of light sensed by an image sensor according to an embodiment;

[0034] Figure 6 is a plan view showing the structure of a nano-optical microlens array that can be disposed in an image sensor according to an embodiment;

[0035] Figure 7 is a plan view showing the structure of a nano-optical microlens array that can be disposed in an image sensor according to an embodiment;

[0036] Figure 8 is a conceptual diagram illustrating the principal ray angle incident on a pixel array of an image sensor according to an embodiment;

[0037] Figure 9A and Figure 9B is a plan view showing the structure of a nano-optical microlens array that can be disposed in an image sensor as viewed from peripheral groups at different positions;

[0038] Figure 10A 、 Figure 10B 、 Figure 10C and Figure 10D is a plan view showing the structure of a nano-optical microlens array that can be disposed in an image sensor as viewed from peripheral groups at different positions;

[0039] Figure 11 is a cross-sectional view of a pixel array including a nano-optical microlens array having another structure;

[0040] Figure 12A is a plan view showing another example of the color arrangement of a pixel array in an image sensor, and Figure 12B 、 Figure 12C and Figure 12D is a plan view showing a sensor substrate, a color filter array, and a nano-optical microlens array disposed in a pixel array of Figure 12A ;

[0041] Figure 13 is a schematic block diagram of an electronic device including an image sensor according to some embodiments; and

[0042] Figure 14 is Figure 13 a schematic block diagram of a camera module included in the electronic device of Detailed Description

[0043] Example embodiments will be described in more detail below with reference to the accompanying drawings.

[0044] In the following description, even in different drawings, the same reference numerals are used for the same elements. The content defined in the description (e.g., detailed configuration and elements) is used to help understand the example embodiments comprehensively. However, it should be clear that the example embodiments can be practiced even without these specific defined contents. In addition, since well-known functions or configurations would obscure the description with unnecessary details, they are not described in detail.

[0045] As used herein, the term “and / or” includes any and all combinations of one or more of the associated listed items. Expressions such as “at least one of...” when following a list of elements modify the entire list of elements, rather than modifying individual elements in the list. For example, the expression “at least one of a, b, and c” should be understood to include only a, only b, only c, both a and b, both a and c, both b and c, all of a, b, and c, or any variations of the foregoing examples.

[0046] Hereinafter, it will be understood that when a component is referred to as being “above” or “on” another component, the component can be directly on the other component or above the other component in a non-contact manner.

[0047] It will be understood that although terms such as “first,” “second,” etc. may be used herein to describe various components, these terms are only used to distinguish one component from another. These terms do not limit the materials or structures of the components from being different from each other.

[0048] Expressions in the singular form cover plural expressions unless having a clearly different meaning in the context. It will also be understood that when a part is referred to as “including” another component, the part may not exclude the other component but may also include the other component, unless otherwise specified in the context.

[0049] In addition, the terms “... unit” and “... module” as used herein designate a unit for processing at least one function or operation, and this can be implemented by hardware or software, or a combination of hardware and software.

[0050] The use of the terms "a", "an", and "the" and similar reference terms shall be construed to cover both the singular and the plural.

[0051] In addition, steps of all the methods described herein may be executed in any suitable order, unless otherwise indicated herein or the context otherwise clearly dictates to the contrary. Further, the use of all example terms provided herein (e.g., etc.) is only intended to better clarify the technical concept and does not impose a limitation on the scope of the claims, unless otherwise required.

[0052] Figure 1 is a block diagram of an image sensor 1000 according to an embodiment. Refer to Figure 1 , the image sensor 1000 may include a pixel array 1100, a timing controller (T / C) 1010, a row decoder 1020, and an output circuit 1030. The image sensor 1000 may include a charge-coupled device (CCD) image sensor or a complementary metal-oxide-semiconductor (CMOS) image sensor.

[0053] The pixel array 1100 includes pixels two-dimensionally arranged in a plurality of rows and columns. The row decoder 1020 selects one of the rows in the pixel array 1100 in response to a row address signal output from the timing controller 1010. The output circuit 1030 outputs a photosensitive signal from a plurality of pixels arranged in the selected row in units of columns. 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 respectively arranged in columns between the column decoder and the pixel array 1100, or one ADC arranged at the output end of the column decoder. The timing controller 1010, the row decoder 1020, and the output circuit 1030 may be implemented as one chip or separate chips. A processor may process an image signal output from the output circuit 1030 in digital form. The processor may be implemented as a single chip together with the timing controller 1010, the row decoder 1020, and the output circuit 1030.

[0054] The pixel array 1100 may include a plurality of pixels PX that sense light of different wavelengths. The pixel color arrangement may be implemented in various ways.

[0055] Figure 2A is a plan view showing the color arrangement of the pixel array 1100 in the image sensor 1000. Figures 2B to 2D are schematic plan views respectively showing a sensor substrate 110, a color filter array 120, and a nano-optical microlens array 130 included in the pixel array 1100. Figure 3A and Figure 3B is along Figure 2D is a cross-sectional view of the pixel array 1100 of the image sensor 1000 taken along line AA' and line BB'.

[0056] Figure 2A The color arrangement shown is similar to the Bayer pattern, but different from the Bayer pattern in that the same colors are adjacent to each other in a 2×2 arrangement. The 2×2 arrangements of the green (G) color, the blue (B) color, the red (R) color, and the green (G) color form a unit pattern UP, and the unit pattern UP is repeated and arranged two-dimensionally. This color arrangement can be used to improve the sensitivity of a super-small image sensor.

[0057] Figure 2A The color arrangement is an example, and the present disclosure is not limited thereto. For example, the CYGM method in which magenta (M), cyan (C), yellow (Y), and green (G) are represented in one unit pattern or the RGBW method in which green (G), red (R), blue (B), and white (W) are represented in one unit pattern can be used. Additionally, the unit pattern can be implemented as a 3×2 array, and the pixels in the pixel array 1100 can be arranged in various ways according to the color characteristics of the image sensor 1000. Hereinafter, an example in which the pixel array 1100 of the image sensor 1000 has a Bayer pattern is described, but the operating principle can be applied to pixel arrangements of types other than the Bayer pattern.

[0058] The pixel array 1100 of the image sensor 1000 may include a sensor substrate 110 having a plurality of pixels for sensing light, a color filter array 120 in which a plurality of color filters are arranged, and a nano-optical microlens array 130 including a plurality of nano-optical microlenses that focus light onto each pixel of the sensor substrate 110. Figures 2B to 2D is a plan view showing the sensor substrate 110, the color filter array 120, and the nano-optical microlens array 130. The sensor substrate 110, the color filter array 120, and the nano-optical microlens array 130 may be arranged in a first direction (Z direction).

[0059] Reference Figure 2B , the sensor substrate 110 may include a plurality of pixels PX that sense incident light (i.e., generate an image signal by converting the incident light into an electrical signal). The plurality of pixels PX may be arranged two-dimensionally in a second direction (X direction) and a third direction (Y direction) perpendicular to the first direction (Z direction). The sensor substrate 110 may include a plurality of unit pixel groups 110G. The unit pixel groups 110G correspond one-to-one to Figure 2AThe unit pattern UP shown. The unit pixel group 110G includes a first pixel group 111, a second pixel group 112, a third pixel group 113, and a fourth pixel group 114. The first pixel group 111 includes four first pixels 11, 12, 13, and 14 arranged in a 2×2 pattern, the second pixel group 112 includes four second pixels 21, 22, 23, and 24 arranged in a 2×2 pattern, the third pixel group 113 includes four third pixels 31, 32, 33, and 34 arranged in a 2×2 pattern, and the fourth pixel group 114 includes four fourth pixels 41, 42, 43, and 44 arranged in a 2×2 pattern. When describing the commonalities among the first to fourth pixels 11 to 14, 21 to 24, 31 to 34, and 41 to 44, the first to fourth pixels 11 to 14, 21 to 24, 31 to 34, and 41 to 44 can be simply collectively referred to as pixels PX.

[0060] The pixel arrangement of the sensor substrate 110 is set to sense incident light by classifying the incident light into colors as shown Figure 2A in the arrangement shown. The first pixel group 111 and the fourth pixel group 114 can be sensitive to green light and capture green light, and thus can correspond to green light. The second pixel group 112 can be sensitive to blue light and capture blue light, and thus can correspond to blue light. The third pixel group 113 can be sensitive to red light and capture red light, and thus can correspond to red light. Hereinafter, the first pixel group 111 can be interchangeably referred to as the first green pixel group, the second pixel group 112 can be interchangeably referred to as the blue pixel group, the third pixel group 113 can be interchangeably referred to as the red pixel group, and the fourth pixel group 114 can be interchangeably referred to as the second green pixel group. Additionally, the first pixels 11 to 14 can be interchangeably used as the first green pixels, the second pixels 21 to 24 can be interchangeably used as the blue pixels, the third pixels 31 to 34 can be interchangeably used as the red pixels, and the fourth pixels 41 to 44 can be interchangeably used as the second green pixels.

[0061] Each pixel PX can include a plurality of photosensitive units that independently sense incident light. For example, as shown in the figure, one pixel PX can include four photosensitive units c1, c2, c3, and c4. However, this is an example, and one pixel PX can be divided into two or more photosensitive units with different numbers. For example, one pixel PX can include two photosensitive units, or a plurality of independent photosensitive units aggregated and arranged in a 3×3 array or a 4×4 array.

[0062] Adjacent pixels PX and multiple photosensitive units within the pixel PX can be electrically separated from each other by an isolation structure. Although simply shown as lines in the drawings, the isolation structure can have a physical thickness. The isolation structure can be formed as, for example, a deep trench isolation (DTI) structure. The deep trench can be filled with air or an electrically insulating material. Multiple electrically separated units can be formed by forming an optical sensing layer and then forming a DTI structure on the optical sensing layer.

[0063] The width of the pixel PX can be referred to as D. At this time, D represents the actual width of the optical sensing region excluding the thickness of the DTI structure. Therefore, D can be less than the period in which the pixel PX is repeated.

[0064] When one pixel PX includes multiple photosensitive units, some of the multiple pixels PX can be used as autofocus (AF) pixels. In the AF pixels, an AF signal can be obtained based on the difference between the output signals of adjacent photosensitive units.

[0065] For example, an AF signal in the second direction (X direction) can be generated based on: the difference between the output signal of the first photosensitive unit c1 and the output signal of the second photosensitive unit c2, the difference between the output signal of the third photosensitive unit c3 and the output signal of the fourth photosensitive unit c4, or the difference between the sum of the output signals of the first photosensitive unit c1 and the third photosensitive unit c3 and the sum of the output signals of the second photosensitive unit c2 and the fourth photosensitive unit c4. Additionally, an AF signal in the third direction (Y direction) can be generated based on: the difference between the output signal of the first photosensitive unit c1 and the output signal of the third photosensitive unit c3, the difference between the output signal of the second photosensitive unit c2 and the output signal of the fourth photosensitive unit c4, or the difference between the sum of the output signals of the first photosensitive unit c1 and the second photosensitive unit c2 and the sum of the output signals of the third photosensitive unit c3 and the fourth photosensitive unit c4.

[0066] Meanwhile, methods for obtaining a general image signal include a summation mode and a full mode. In the summation mode, an image signal can be obtained by summing the output signals of the first to fourth photosensitive units c1, c2, c3, and c4. For example, a first green image signal can be generated by summing the output signals of the first to fourth photosensitive units c1, c2, c3, and c4 of the first pixel group 111, a blue image signal can be generated by summing the output signals of the first to fourth photosensitive units c1, c2, c3, and c4 of the second pixel group 112, a red image signal can be generated by summing the output signals of the first to fourth photosensitive units c1, c2, c3, and c4 of the third pixel group 113, and a second green image signal can be generated by summing the output signals of the first to fourth photosensitive units c1, c2, c3, and c4 of the fourth pixel group 114. In the full mode, each output signal is obtained by using each of the first to fourth photosensitive units c1, c2, c3, and c4 as a separate pixel. In this case, an image with high resolution can be obtained.

[0067] Reference Figure 2C , the color filter array 120 may include a plurality of color filters that selectively transmit light of different wavelength bands among incident light. The plurality of color filters may correspond one-to-one to Figure 2B the plurality of pixel groups of the sensor substrate 110 shown. For example, the color filter array 120 may include a first color filter 121 disposed facing the first pixel group 111, a second color filter 122 disposed facing the second pixel group 112, a third color filter 123 disposed facing the third pixel group 113, and a fourth color filter 124 disposed facing the fourth pixel group 114. Similar to the first to fourth pixel groups 111, 112, 113, and 114, a unit group including the plurality of first to fourth color filters 121, 122, 123, and 124 may be two-dimensionally arranged in the second direction (X direction) and the third direction (Y direction).

[0068] The first color filter 121 and the fourth color filter 124 may be green filters that transmit light in the green wavelength band among incident light and block (e.g., absorb) light in other wavelength bands, the second color filter 122 may be a blue filter that transmits light in the blue wavelength band among incident light and blocks light in other wavelength bands, and the third color filter 123 may be a red filter that transmits light in the red wavelength band among incident light and blocks light in other wavelength bands. The first to fourth color filters 121, 122, 123, and 124 may be organic color filters each including an organic dye or an organic pigment.

[0069] Reference Figure 2D, the nano-optical microlens array 130 may include a plurality of first nano-optical microlenses 131, a plurality of second nano-optical microlenses 132, a plurality of third nano-optical microlenses 133, and a plurality of fourth nano-optical microlenses 134. The nano-optical microlens array 130 may include four first nano-optical microlenses 131 that face the first pixels 11, 12, 13, and 14 one by one and converge light onto the first pixels 11, 12, 13, and 14 respectively, four second nano-optical microlenses 132 that face the second pixels 21, 22, 23, and 24 one by one and converge light onto the second pixels 21, 22, 23, and 24 respectively, four third nano-optical microlenses 133 that face the third pixels 31, 32, 33, and 34 one by one and converge light onto the third pixels 31, 32, 33, and 34 respectively, and four fourth nano-optical microlenses 134 that face the fourth pixels 41, 42, 43, and 44 one by one and converge light onto the fourth pixels 41, 42, 43, and 44 respectively. The 16 first to fourth nano-optical microlenses 131, 132, 133, and 134 may form a lens group facing one unit pixel group 110G, and a plurality of lens groups may be arranged two-dimensionally and repeatedly. Figure 2D Only one lens group is shown.

[0070] As referred to Figures 2A to 2D above, the following structure may be referred to as a Tetra Square structure: pixels representing the same color form a group of four units arranged in a 2×2 pattern, each pixel PX includes four photosensitive units, and a plurality of nano-optical microlenses face a plurality of pixels PX one by one. As described above, the four photosensitive units c1, c2, c3, and c4 included in each pixel PX may be used only for generating an AF signal and not as independent image pixels, or may be used for generating an AF signal and as independent image pixels.

[0071] Each of the first nano-optical microlens 131, the second nano-optical microlens 132, the third nano-optical microlens 133, and the fourth nano-optical microlens 134 may have a nano-pattern structure capable of converging light. The nano-pattern structure may include a plurality of nanostructures NP that differently change the phase of incident light according to the incident position. The shape, size (width and height), distance, arrangement form, etc. of the plurality of nanostructures NP may be determined such that the light immediately after passing through each of the first nano-optical microlens 131, the second nano-optical microlens 132, the third nano-optical microlens 133, and the fourth nano-optical microlens 134 has a specific phase profile. According to the phase profile, the traveling direction and focal length of the light passing through each of the first nano-optical microlens 131, the second nano-optical microlens 132, the third nano-optical microlens 133, and the fourth nano-optical microlens 134 may be determined. In other words, according to the phase profile, the detailed shape and arrangement of the nanostructures NP included in each of the first nano-optical microlens 131, the second nano-optical microlens 132, the third nano-optical microlens 133, and the fourth nano-optical microlens 134 may be determined. Additionally, the detailed shape and arrangement of the nanostructures NP may be determined according to the relative position of the lens group to which the nanostructures NP belong within the nano-optical microlens array 130. For example, the nanostructures NP may be arranged along the circumferences of two concentric circles (a first circle C1 having a first diameter d and a second circle C2 having a second diameter d greater than the first diameter d). The nanostructures NP may be positioned away from the pixel boundaries and the center of the concentric circles to reduce crosstalk between adjacent pixels and allow for sharper focusing on the pixel center, thereby enhancing the autofocus ability. 2 The nanostructures NP may be positioned away from the pixel boundaries and the center of the concentric circles to reduce crosstalk between adjacent pixels and allow for sharper focusing on the pixel center, thereby enhancing the autofocus ability.

[0072] Reference Figure 3A and Figure 3B and Figures 2A to 2D described, the pixel array 1100 includes a sensor substrate 110 and a nano-optical microlens array 130 disposed on the sensor substrate 110. A color filter array 120 may be further disposed between the sensor substrate 110 and the nano-optical microlens array 130. The first pixels 11, 12, 13, and 14, the second pixels 21, 22, 23, and 24, the third pixels 31, 32, 33, and 34, and the fourth pixels 41, 42, 43, and 44 of the sensor substrate 110, the first color filter to the fourth color filter 121, 122, 123, 124 of the color filter array 120, and the first nano-optical microlens to the fourth nano-optical microlens 131, 132, 133, and 134 of the nano-optical microlens array 130 may have a corresponding relationship as described in reference

[0073] A planarization layer 125 may be further disposed between the color filter array 120 and the nano-optical microlens array 130. The upper surfaces of the first to fourth color filters 121, 122, 123, and 124 are shown to be flat, but this is an example, and the upper surface may not be flat. Additionally, the thicknesses of the first to fourth color filters 121, 122, 123, and 124 and the black matrix therebetween may not be the same. The planarization layer 125 may be used to provide a flat surface for forming the nano-optical microlens array 130 on the color filter array 120. The planarization layer 125 may include an organic polymer material suitable for stacking and easily forming a flat surface on the first to fourth color filters 121, 122, 123, and 124 including organic materials. The organic polymer material forming the planarization layer 125 may have a transparent property with respect to visible light. For example, the planarization layer 125 may include at least one organic polymer material among epoxy resin, polyimide, polycarbonate, polyacrylate, and polymethyl methacrylate (PMMA). An encapsulation layer may be further disposed on the planarization layer 125. The encapsulation layer may serve as a protective layer that prevents the planarization layer 125 including the organic polymer material from being damaged during the process of forming the nano-optical microlens array 130 on the planarization layer 125. Additionally, the encapsulation layer may serve as an anti-diffusion layer that prevents the metal components of the color filter array 120 from passing through the planarization layer 125 and being exposed to the outside due to high temperature during the process of forming the nano-optical microlens array 130. To this end, the encapsulation layer may include an inorganic material. The inorganic material of the encapsulation layer may be formed at a temperature lower than the process temperature for forming the nano-optical microlens array 130 and may include a material transparent with respect to visible light. Additionally, in order to reduce the reflection loss at the interface between the planarization layer 125 and the encapsulation layer, it is advantageous that the refractive index of the encapsulation layer is similar to the refractive index of the planarization layer 125. For example, the difference between the refractive index of the planarization layer 125 and the refractive index of the encapsulation layer may be within ±20% of the refractive index of the planarization layer 125. For example, the encapsulation layer may include at least one inorganic material among SiO 2 , SiN, and SiON.

[0074] The planarization layer 125 may be formed to a thickness that satisfies appropriate distance requirements related to the focal lengths of the first to fourth nano-optical microlenses 131, 132, 133, and 134. The planarization layer 125 is an example and may be omitted in some cases.

[0075] Each of the first to fourth nano-optical microlenses 131, 132, 133, and 134 may include a plurality of nanostructures NP. The nanostructure NP may be a nanocolumn having a sub-wavelength-sized cross-sectional diameter. Here, sub-wavelength refers to less than the wavelength of the light band to be converged. When the incident light is visible light, the cross-sectional diameter of the nanostructure NP may have a size less than, for example, 400 nm, 300 nm, 200 nm, or 100 nm. At the same time, the height of the nanostructure NP may be about 500 nm to about 1500 nm and may be greater than the cross-sectional diameter. That is, the aspect ratio of the nanostructure NP may be greater than 1, for example, 2 or greater, 3 or greater, or 5 or greater.

[0076] The nanostructure NP may include a material having a relatively high refractive index compared to the peripheral material and a relatively low absorption rate in the visible light band. For example, the nanostructure NP may include c-Si, p-Si, a-Si, and III-V group compound semiconductors (GaP, GaN, GaAs, etc.), SiC, TiO 2 、SiN 3 、ZnS, ZnSe, Si 3 N 4 and / or combinations thereof. The region around the nanostructure NP may be filled with a dielectric material DL having a relatively low refractive index compared to the nanostructure NP and a relatively low absorption rate in the visible light band. For example, the region around the nanostructure NP may be filled with silanol-based glass (SOG), SiO 2 、Al 2 O 3 、air, etc.

[0077] The refractive index of the nanostructure NP having a high refractive index may be about 2.0 or greater with respect to light having a wavelength of about 630 nm, and the refractive index of the dielectric material DL having a low refractive index may be about 1.0 or greater and less than 2.0 with respect to light having a wavelength of about 630 nm. In addition, the difference between the refractive index of the nanostructure NP and the refractive index of the dielectric material DL may be about 0.5 or greater. The nanostructure NP having a refractive index different from that of the peripheral material may change the phase of the light passing through the nanostructure NP. This is caused by the phase delay that occurs due to the sub-wavelength-shaped size of the nanostructure NP, and the degree of the phase delay can be determined by the detailed shape size and arrangement shape of the nanostructure NP.

[0078] Figure 3A and Figure 3BIt shows that the nano-optical microlens array 130 and the sensor substrate 110 are aligned such that the centers of the corresponding lenses and pixels are aligned. That is, the center of the first pixel 11 is aligned with the center of the first nano-optical microlens 131 facing the first pixel 11, the center of the first pixel 12 is aligned with the center of the first nano-optical microlens 131 facing the first pixel 12, the center of the second pixel 21 is aligned with the center of the second nano-optical microlens 132 facing the second pixel 21, and the center of the second pixel 22 is aligned with the center of the second nano-optical microlens 132 facing the second pixel 22. The centers of the third pixels 31 and 32 and the center of the third nano-optical microlens 133, and the centers of the fourth pixels 41 and 42 and the center of the fourth nano-optical microlens 134 are similarly arranged. This arrangement shows the center where the principal ray angle of the incident light is 0 degrees, and at other positions, the centers of the nano-optical microlenses and the centers of the pixels facing the nano-optical microlenses may not be aligned. The degree of misalignment can increase as the distance from the center of the nano-optical microlens array 130 increases.

[0079] At the shown positions, the plurality of nanostructures NP included in each of the first to fourth nano-optical microlenses 131, 132, 133, and 134 may have such a shape and arrangement that the shape and arrangement form a phase profile with a raised center. That is, the shape and arrangement of the plurality of nanostructures NP included in each of the first to fourth nano-optical microlenses 131, 132, 133, and 134 can be determined such that the plurality of nanostructures NP act as convex lenses that respectively converge the incident light with a principal ray angle of 0 degrees onto the first to fourth pixels 11, 12, 21, 22, 31, 32, 41, and 42.

[0080] Compared with a general converging lens having a curved light incident surface, each of the first to fourth nano-optical microlenses 131, 132, 133, and 134 has a flat light incident surface and can be referred to as a flat nano-optical microlens.

[0081] As described above, the light incident on the pixel array 1100 can pass through the nano-optical microlens array 130 and have a specific light convergence distribution. Among the light passing through the nano-optical microlens array 130, green light can pass through the first color filter 121 and the fourth color filter 124 and converge onto the four first pixels 11, 12, 13, and 14 and the four fourth pixels 41, 42, 43, and 44, blue light can pass through the second color filter 122 and converge onto the four second pixels 21, 22, 23, and 24, and red light can pass through the third color filter 123 and converge onto the four third pixels 31, 32, 33, and 34.

[0082] In addition to the above-described light converging performance, the nanostructured NP arrangement of the nano-optical microlens array 130 provided in the pixel array 1100 according to the embodiment is set in consideration of improved AF performance and reduction of crosstalk between adjacent pixels.

[0083] Referring again to Figure 2D , the arrangement of the nanostructured NPs will be described in detail.

[0084] The nanostructured NPs forming a first nano-optical microlens 131 may not be uniformly distributed over the entire area within the first nano-optical microlens 131, but may be arranged mostly within a specific area. For example, the nanostructured NPs may be arranged mostly within a reference circle RC having a diameter equal to the width D of the first pixel 11 facing the reference circle RC. In the drawings, all the nanostructured NPs are arranged within the reference circle RC, but this is an example. In the shown plan view, when the ratio of the area of the nanostructured NPs arranged within the reference circle RC to the entire area of the nanostructured NPs included in the first nano-optical microlens 131 is referred to as the fill factor, the fill factor may be 90% or greater, or 95% or greater.

[0085] Even within each of the second nano-optical microlens 132, the third nano-optical microlens 133, and the fourth nano-optical microlens 134, the fill factor may be 90% or greater, or 95% or greater.

[0086] The first nano-optical microlens 131, the second nano-optical microlens 132, and the third nano-optical microlens 133 may have different fill factors. In the drawings, the nanostructured NPs included in the first to fourth nano-optical microlenses 131, 132, 133, and 134 have the same number and similar sizes, but this is an example. The nanostructured NPs provided in the second nano-optical microlens 132 corresponding to the blue pixels may have a larger cross-sectional area than the nanostructured NPs provided in each of the first nano-optical microlens 131, the third nano-optical microlens 133, and the fourth nano-optical microlens 134, or may also be a larger number. Therefore, the fill factor of the nanostructured NP arrangement of the second nano-optical microlens 132 may be smaller than the fill factors of the first nano-optical microlens 131 and the third nano-optical microlens 133.

[0087] The arrangement of the nanostructured NPs may be described as an N×N matrix defined on the shown X-Y plane. Here, N may be an integer of 3 or greater. The arrangement of the nanostructured NPs may be determined such that the nanostructured NPs are not provided at one or more of the four positions (1, 1), (1, N), (N, 1), and (N, N) on the N×N matrix. In other words, the nanostructured NPs may be arranged in such a way that N2 One nanostructured NP is aligned in N rows and N columns, and then one or more of the four nanostructured NPs located at the four corners are excluded or removed so that the nanostructured NPs are positioned away from the four corners of each of the nano-optical microlenses 131 to 134. Figure 2D It is shown that for N = 4, the nanostructured NPs are not located at all four corner positions but only at the remaining N 2 - 4 positions (i.e., 12 positions).

[0088] The nanostructured NPs are arranged as described above to correct the phase profile formed by the nano-optical microlenses to a nearly circular shape and to reduce crosstalk with adjacent pixels. Additionally, the focal point formed by the nano-optical microlenses can be on the center of the corresponding pixel, thereby improving the AF performance.

[0089] Figure 4A and Figure 4B are plan views showing the nano-optical microlens array 1 and the nano-optical microlens array 2 according to Comparative Example 1 and Comparative Example 2.

[0090] Figure 4A The nano-optical microlens array 1 of Comparative Example 1 shown shows a lens group corresponding to Figure 2D and the nanostructured NPs included in each nano-optical microlens are arranged in an N×N shape. The phase of the incident light caused by this arrangement of the nanostructured NPs can exhibit a phase profile PC that is nearly square.

[0091] Figure 4B The nano-optical microlens array 2 of Comparative Example 2 shown has an arrangement of nanostructured NPs corresponding to a form that is rotated 45 degrees from the arrangement of the nanostructured NPs of Figure 4A . The phase of the incident light caused by this arrangement of the nanostructured NPs can have a phase profile PC that is nearly circular in shape. In Figure 4B , the nanostructured NPs can be located at positions corresponding to the pixel boundaries.

[0092] Figure 5A , Figure 5B and Figure 5C are respectively calculation simulation curves showing the spectra of the light sensed by an image sensor including the nano-optical microlens arrays according to Comparative Example 1, Comparative Example 2, and the Example.

[0093] In the curves, RL, GL, and BL are the spectra of red light, green light, and blue light respectively, and the dashed line is the spectrum in the case where the image sensor includes a general microlens array.

[0094] Figure 5A , Figure 5B and Figure 5CIt is shown that the nano-optical microlens arrays of Comparative Example 1, Comparative Example 2, and the Example all exhibit a quantum efficiency (QE) similar to that in the case where the image sensor includes a general microlens array.

[0095] The AF performance and crosstalk in the image sensors of Comparative Example 1, Comparative Example 2, and the Example are shown in detail in the following table.

[0096] [Table 1]

[0097]

[0098] R, Gb, Gr, and B respectively indicate the contrast ratio (CR ratio) in the channels of the red pixel, the first green pixel, the second green pixel, and the blue pixel. The larger the contrast ratio, the greater the AF sensitivity, that is, it can be evaluated that the AF performance is improved. CTK is a numerical representation of the signal overlap (i.e., crosstalk) between adjacent pixels.

[0099] In the case of this Example, compared with Comparative Example 1 and Comparative Example 2, the crosstalk is smaller, and the AFCR in each pixel is larger.

[0100] Hereinafter, various examples of the nano-optical microlens array that can improve the AF performance and reduce the crosstalk are described.

[0101] Figure 6 is a plan view showing the structure of the nano-optical microlens array 130A that can be provided in the image sensor according to the Example.

[0102] The nano-optical microlens array 130A of this Example is different from Figure 2D the nano-optical microlens array 130 shown in that the number of nanostructures NP included in each of the first to fourth nano-optical microlenses 131, 132, 133, and 134.

[0103] The nanostructures NP are arranged in a 5×5 matrix and are not at the four corner positions (i.e., (1, 1), (1, 5), (5, 1), and (5, 5)) represented as X Figure 6 in 1 Y 1 、X 1 Y 5 、X 5 Y 1 and X 5 Y 5 of the 5×5 matrix.

[0104] Figure 7 is a plan view showing the structure of the nano-optical microlens array 130B that can be provided in the image sensor according to the Example.

[0105] The nano-optical microlens array 130B of this embodiment and Figure 2D and Figure 6 the nano-optical microlens arrays 130 and 130A shown are different in that: the number of nanostructures NP provided in the second nano-optical microlens 132 is different from the number of nanostructures NP provided in each of the first nano-optical microlens 131, the third nano-optical microlens 133, and the fourth nano-optical microlens 134. The nanostructures NP of the second nano-optical microlens 132 are arranged based on 5×5, and the nanostructures NP of each of the first nano-optical microlens 131, the third nano-optical microlens 133, and the fourth nano-optical microlens 134 are arranged based on 4×4.

[0106] Figure 6 and Figure 7 The number of nanostructures NP provided in each of the first to fourth nano-optical microlenses 131, 132, 133, and 134 shown is an example and can be changed differently. For example, the nanostructures NP provided in each of the first to fourth nano-optical microlenses 131, 132, 133, and 134 can all have an arrangement based on 3×3 or an arrangement based on N×N, where N is greater than 5. Alternatively, the number of nanostructures NP provided in the first nano-optical microlens 131, the second nano-optical microlens 132, and the third nano-optical microlens 133 can all be different. In this case, the number of nanostructures NP provided in the second nano-optical microlens 132 corresponding to the blue pixel is the largest, and the number of nanostructures NP provided in the third nano-optical microlens 133 corresponding to the red pixel can be the smallest. For example, the first nano-optical microlens 131 can be arranged based on 4×4, the second nano-optical microlens 132 can be arranged based on 5×5, and the third nano-optical microlens 133 can be arranged based on 3×3.

[0107] The arrangement of the nanostructures NP in the nano-optical microlens arrays 130, 130A, and 130B shows a lens group. The arrangement of the nanostructures NP can vary according to the position of the lens group and the relative position of the lens group within the nano-optical microlens arrays 130, 130A, and 130B. This takes into account that the chief ray angle of the light incident on the image sensor varies according to the position.

[0108] Figure 8 is a conceptual diagram illustrating the chief ray angle of the light incident on the pixel array 1100 of the image sensor according to the embodiment.

[0109] The pixel array 1100 of an image sensor can be employed in a camera module together with the module lens ML, and the light guided to the pixel array 1100 through the module lens ML can have different incident angles according to the position of the pixel array 1100. The incident angle of the light incident on the pixel array 1100 can be represented by or defined as the chief ray angle CRA. The chief ray CR refers to the ray starting from a point on the object, passing through the center of the module lens ML, and incident on the pixel array 1100, and the CRA refers to the angle formed by the chief ray CR and the optical axis OX.

[0110] The CRA of the light incident on the center C of the nano-optical microlens array 130 is 0 degrees, and the farther away from the center (i.e., toward the periphery of the nano-optical microlens array 130), the larger the CRA of the light incident on the corresponding lens group at that position. Additionally, even when the CRA is the same, the direction of the chief ray changes according to the azimuthal position of the corresponding lens group. The azimuthal angle can be defined as the angle formed with a reference direction on a plane perpendicular to the optical axis OX, for example, the angle formed with the X direction on the X-Y plane.

[0111] In the arrangement of the nanostructures in the lens groups included in the nano-optical microlens array 130, the magnitude and direction of the CRA can be considered. Hereinafter, the position where the CRA is 0 degrees or close to 0 degrees is referred to as the center, and other positions are referred to as the periphery, and the lens group located at the center of the nano-optical microlens array 130 is referred to as the central group, and the lens group located at the periphery is referred to as the peripheral group PG. The position that can be regarded as the center is not limited to the exact center position of the nano-optical microlens array 130, and can be defined as the position where the CRA is within a specific range. For example, for convenience, the range of the center can be defined, for example, the CRA is within 5%, 10%, or 20% of the maximum CRA.

[0112] As described above, configuring the nano-optical microlens array 130 by differentiating between the center and the periphery takes into account that the nano-optical microlens array 130 operates effectively with respect to light incident within a specific angular range. However, when the incident angle is away from the specific angular range, the light converging performance of the nano-optical microlens array 130 may deteriorate, and the effects of improving the AF performance or reducing crosstalk as described above may decrease.

[0113] Figure 9A and Figure 9B are plan views showing the structure of the nano-optical microlens array 130C that can be provided in an image sensor according to an embodiment as viewed from the peripheral groups PG1 and PG2 at different positions.

[0114] In Figure 9A the nano-optical microlens array 130C shows the peripheral group PG1, and inFigure 9B In [description], the nano-optical microlens array 130C shows the peripheral group PG2. The peripheral group PG1 is at the position with an azimuth angle of 180 degrees, and the peripheral group PG2 is at the position with an azimuth angle of 0 degrees.

[0115] The nanostructures NP disposed on the first to fourth nano-optical microlenses 131, 132, 133, and 134 included in the peripheral group PG1 can be arranged based on 4×4. And in the second and third rows, the nanostructures NP are arranged in the order of increasing size toward the center (i.e., toward the right). Similar to the above-described nano-optical microlens arrays 130, 130A, and 130B, the nanostructures NP are not located at the positions (1, 1), (1, 4), (4, 1), and (4, 4).

[0116] The nanostructures NP disposed on the first to fourth nano-optical microlenses 131, 132, 133, and 134 included in the peripheral group PG2 can also be arranged based on 4×4. And in the second and third rows, the nanostructures NP are arranged in the order of increasing size toward the center (i.e., toward the left). Similar to the above-described nano-optical microlens arrays 130, 130A, and 130B, the nanostructures NP are not located at the positions (1, 1), (1, 4), (4, 1), and (4, 4).

[0117] The lens groups disposed in the nano-optical microlens array 130C have been described as two peripheral groups PG1 and PG2. However, similarly, in the peripheral groups at other azimuth angle positions, the nanostructures NP can be arranged in the order of increasing size toward the center. For example, at the positions with azimuth angles of 90 degrees and 270 degrees, the nanostructures NP in the second and third columns can be arranged in the order of increasing size toward the center.

[0118] Among the lens groups disposed in the nano-optical microlens array 130C, the central group can have the arrangement of the nanostructures NP as Figure 2D shown.

[0119] Figures 10A to 10D is a plan view showing the structure of the nano-optical microlens array 130D that can be disposed in an image sensor according to an embodiment, as observed from the peripheral groups PG1, PG2, PG3, and PG4 at different positions.

[0120] In the nano-optical microlens array 130D of the present embodiment, the nanostructures NP of the first to fourth nano-optical microlenses 131, 132, 133, and 134 of the lens group at the periphery may not be located at some of the four positions (1, 1), (1, N), (N, 1), and (N, N). In other words, the nanostructures NP may not be disposed at two of the four positions (1, 1), (1, N), (N, 1), and (N, N), and may be disposed at the remaining N 2 -2 positions. The combination of the two positions where the nanostructures NP are not disposed may vary according to the azimuth angle. Alternatively, the nanostructures NP may not be disposed at three of the four positions (1, 1), (1, N), (N, 1), and (N, N), and may be disposed at the remaining N 2 -3 positions. The combination of the three positions where the nanostructures NP are not disposed may vary according to the azimuth angle. Alternatively, the nanostructures NP may not be disposed at one of the four positions (1, 1), (1, N), (N, 1), and (N, N), and may be disposed at the remaining N 2 -1 position. The one position where the nanostructures NP are not disposed may vary according to the azimuth angle.

[0121] Figures 10A to 10D The peripheral groups PG1, PG2, PG3, and PG4 shown are the positions with azimuth angles of 180 degrees, 0 degrees, 270 degrees, and 90 degrees, respectively.

[0122] The first to fourth nano-optical microlenses 131, 132, 133, and 134 belonging to the corresponding positions include rows or columns of nanostructures NP arranged such that the size of the nanostructures NP increases toward the center. The specific positions where the nanostructures NP are not disposed are different from each other according to the azimuth angle.

[0123] Regarding Figure 10A the peripheral group PG1 with an azimuth angle of 180 degrees, in the second and third rows, the nanostructures NP are arranged to become larger toward the right side (i.e., in the +X direction as the central direction), and the nanostructures NP are not disposed at the positions (1, 1) and (4, 1), and are disposed at the remaining 14 positions.

[0124] Regarding Figure 10B the peripheral group PG2 with an azimuth angle of 0 degrees, in the second and third rows, the nanostructures NP are arranged to become larger toward the left side (i.e., in the -X direction as the central direction), and the nanostructures NP are not disposed at the positions (1, 4) and (4, 4), and are disposed at the remaining 14 positions.

[0125] Regarding Figure 10CThe peripheral group PG3 with an azimuth angle of 270 degrees, in the second and third columns, the nanostructures NP are arranged to become larger upward (i.e., in the +Y direction which is the central direction), and the nanostructures NP are not arranged at positions (4, 1) and (4, 4), and are arranged at the remaining 14 positions.

[0126] Regarding Figure 10D The peripheral group PG4 with an azimuth angle of 90 degrees, in the second and third columns, the nanostructures NP are arranged to become larger downward (i.e., in the -Y direction which is the central direction), and the nanostructures NP are not arranged at positions (1, 1) and (1, 4), and are arranged at the remaining 14 positions.

[0127] In the case of the peripheral groups with azimuth angles of 45 degrees, 135 degrees, 225 degrees, and 315 degrees, the positions where the nanostructures NP are not arranged can be determined in a manner similar to the above. For example, the nanostructures NP can not be arranged at the position farthest from the center among the four positions, and the nanostructures NP can be arranged at the remaining N 2 -1 positions. Alternatively, the nanostructures NP can not be arranged at three of the four positions except the one closest to the center, and the nanostructures NP can be arranged at the remaining N 2 -3 positions.

[0128] In the above description, the arrangement of the nanostructures NP of each of the first to fourth nano-optical microlenses 131, 132, 133, and 134 is based on N×N, where N is 4, and all cases are the same, but not limited to this. N can be 3, or 5 or larger, or similar to Figure 7 as described in, N in the second nano-optical microlens 132 can be different from N of each of the first nano-optical microlens 131, the third nano-optical microlens 133, and the fourth nano-optical microlens 134.

[0129] The central group of the nano-optical microlens array 130D can include the first to fourth nano-optical microlenses 131, 132, 133, and 134 as Figure 2D described in.

[0130] As described above, the nanostructures NP of the first to fourth nano-optical microlenses 131, 132, 133, and 134 are arranged by dividing into a central group and a peripheral group, and thus, the filling factor defined by the reference circle RC can be different between the central group and the peripheral group. For example, the filling factor of the peripheral group can be smaller than that of the central group. The filling factor of the peripheral group with a larger CRA can be smaller than that of the peripheral group with a smaller CRA. The filling factor of the central group can be greater than 90%, greater than 95%, or close to 100%. For example, the filling factor in the central group located at the center of the nano-optical microlens array 130 can be 100%.

[0131] Figure 11 is a cross-sectional view showing the pixel array 1100 including the nano-optical microlens array 130E including another structure.

[0132] The nano-optical microlens array 130E in the pixel array 1100 of this embodiment is different from the above-mentioned nano-optical microlens array in that: the nano-optical microlens array 130E includes a first nanostructure NP1 and a second nanostructure NP2 which are arranged and divided into a first layer LE1 and a second layer LE2.

[0133] The arrangement of the above-mentioned nanostructure NP can be applied to both the first nanostructure NP1 of the first layer LE1 and the second nanostructure NP2 of the second layer LE2, or can be applied to only either layer. For example, the arrangement of the above-mentioned nanostructure NP can be applied to only the second nanostructure NP2 of the second layer LE2.

[0134] As an example, the above-mentioned pixel array 1100 has a square arrangement, but in another embodiment, the pixel array 1100 can have a different arrangement.

[0135] Figure 12A is a plan view showing another example of the color arrangement of the pixel array 1100 in the image sensor, and Figure 12B 、 Figure 12C and Figure 12D is a schematic plan view showing the sensor substrate 110, the color filter array 120, and the nano-optical microlens array 130F provided in the Figure 12A pixel array 1100.

[0136] As Figure 12A shown, the pixel array 1100 can have a color arrangement of a general Bayer pattern. As Figure 12BAs shown, the sensor substrate 110 includes a plurality of unit pixel groups 110G, and each unit pixel group 110G includes first to fourth pixels 11, 21, 31, and 41 arranged in a 2×2 manner. The first to fourth pixels 11, 21, 31, and 41 may each include four photosensitive units c1, c2, c3, and c4 arranged in a 2×2 manner. Refer to Figure 12C , the color filter array 120 includes first to fourth color filters 121, 122, 123, and 124 facing the first to fourth pixels 11, 21, 31, and 41, respectively. Refer to Figure 12D , the nano-optical microlens array 130F includes first to fourth nano-optical microlenses 131, 132, 133, and 134 facing the first to fourth pixels 11, 21, 31, and 41, respectively. That is, the nano-optical microlens array 130F of the present embodiment is different from the nano-optical microlens array 130 described in Figure 2D in that each of the first to fourth nano-optical microlenses 131, 132, 133, and 134 is included in one lens group.

[0137] The pixel array 1100 may be referred to as a quad-cell (Qcell) structure. In the Qcell structure, each pixel is divided into four smaller sub-pixels that operate independently and sense incident light, and the sub-pixels are referred to as photosensitive units (for example, Figure 2B the four photosensitive units c1 to c4 within a single pixel 11 in ). Compared with a conventional Bayer color filter array using patterns of a red color filter, a green color filter, and a blue color filter above the pixels, this arrangement provides enhanced light sensitivity and more accurate color reproduction.

[0138] As described above, the fill factor, the positions where nanostructures NP are not provided in the N×N-based arrangement, the relationship between the number N and the corresponding pixels, the differences in the arrangement of nanostructures NP in the peripheral group and the central group, the bilayer arrangement of nanostructures NP, etc. can be equivalently applied to the pixel array of the Qcell structure.

[0139] Figure 13 is a schematic block diagram of an electronic device ED01 including an image sensor according to some embodiments. Figure 14 is Figure 13 a schematic block diagram of a camera module ED80 included in the electronic device ED01.

[0140] Refer to Figure 13, in a network environment ED00, an electronic device ED01 may communicate with another electronic device ED02 via a first network ED98 (e.g., a short-range wireless communication network, etc.), or may communicate with another electronic device ED04 and / or a server ED08 via a second network ED99 (e.g., a long-range wireless communication network, etc.). The electronic device ED01 may communicate with the electronic device ED04 via the server ED08. The electronic device ED01 may include a processor ED20, a memory ED30, an input device ED50, a sound output device ED55, a display device ED60, an audio module ED70, a sensor module ED76, an interface ED77, a haptic module ED79, a camera module ED80, a power management module ED88, a battery ED89, a communication module ED90, a subscriber identification module ED96, and / or an antenna module ED97. In the electronic device ED01, some components (e.g., the display device ED60, etc.) may be omitted, or another component may be added. Some components may be configured as an integrated circuit. For example, the sensor module ED76 (e.g., a fingerprint sensor, an iris sensor, an illuminance sensor, etc.) may be embedded and implemented in the display device ED60 (e.g., a display, etc.).

[0141] The processor ED20 may control one or more components (e.g., hardware, software components, etc.) connected to the processor ED20 of the electronic device ED01 by executing software (e.g., a program ED40, etc.), and may perform various data processing or operations. As part of the data processing or operations, the processor ED20 may load commands and / or data received from another component (e.g., the sensor module ED76, the communication module ED90, etc.) into the volatile memory ED32, may process the commands and / or data stored in the volatile memory ED32, and may store the resulting data in the non-volatile memory ED34. The processor ED20 may include a main processor ED21 (e.g., a central processing unit, an application processor, etc.), and a co-processor ED23 (e.g., a graphics processing unit, an image signal processor, a sensor hub processor, a communication processor, etc.) that may operate independently of the main processor ED21 or together with the main processor ED21. The co-processor ED23 may use less power than the main processor ED21 and may perform specified functions.

[0142] The auxiliary processor ED23 can control functions and / or states related to some components (e.g., display device ED60, sensor module ED76, communication module ED90, etc.) in the electronic device ED01 on behalf of the main processor ED21 when the main processor ED21 is in an inactive state (e.g., sleep state), or together with the main processor ED21 when the main processor ED21 is in an active state (e.g., application execution state). The auxiliary processor ED23 (e.g., image signal processor, communication processor, etc.) can be implemented as part of another component (e.g., camera module ED80, communication module ED90, etc.) that is functionally related to it.

[0143] The memory ED30 can store various data required by components (e.g., processor ED20, sensor module ED76, etc.) of the electronic device ED01. The data can include, for example, input data and / or output data related to software (e.g., program ED40, etc.) and commands associated therewith. The memory ED30 can include volatile memory ED32 and / or non-volatile memory ED34. The non-volatile memory ED34 can include internal memory ED36 and / or external memory ED38.

[0144] The program ED40 can be stored in the memory ED30 as software, and can include an operating system ED42, middleware ED44, and / or applications ED46.

[0145] The input device ED50 can receive commands and / or data to be used in components (e.g., processor ED20, etc.) of the electronic device ED01 from the outside of the electronic device ED01 (e.g., user input, etc.). The input device ED50 can include a microphone, a mouse, a keyboard, and / or a digital pen (e.g., a stylus).

[0146] The sound output device ED55 can output a sound signal to the outside of the electronic device ED01. The sound output device ED55 can include a speaker and / or a receiver. The speaker can be used for general purposes such as multimedia reproduction or recording playback, and the receiver can be used for receiving calls. The receiver can be coupled as part of the speaker, or can be implemented as an independent device.

[0147] The display device ED60 can provide visual information to the outside of the electronic device ED01. The display device ED60 can include a display, a holographic device, or a projector, and a control circuit for controlling the corresponding device. The display device ED60 can include a touch circuit configured to sense a touch and / or a sensor circuit (e.g., a pressure sensor, etc.) configured to measure the intensity of the force generated by the touch.

[0148] The audio module ED70 can convert sound into an electrical signal and vice versa. The audio module ED70 can obtain sound through the input device ED50, or can output sound via the sound output device ED55 and / or the speakers and / or headphones of another electronic device (e.g., electronic device ED02, etc.) directly or wirelessly connected to the electronic device ED01.

[0149] The sensor module ED76 can sense the operating state (power, temperature, etc.) of the electronic device ED01 or the external environmental state (e.g., user state, etc.), and can generate an electrical signal and / or data value corresponding to the sensed state. The sensor module ED76 can include a gesture sensor, a gyro sensor, a pressure sensor, a magnetic sensor, an acceleration sensor, a grip sensor, a proximity sensor, a color sensor, an infrared (IR) line sensor, an in-body sensor, a temperature sensor, a humidity sensor, and / or an illuminance sensor.

[0150] The interface ED77 can support one or more specified protocols that can be used to directly or wirelessly connect the electronic device ED01 to another electronic device (e.g., electronic device ED02, etc.). The interface ED77 can include a high-definition multimedia interface (HDMI), a universal serial bus (USB) interface, an SD card interface, and / or an audio interface.

[0151] The connection terminal ED78 can include a connector through which the electronic device ED01 can be physically connected to another electronic device (e.g., electronic device ED02, etc.). The connection terminal ED78 can include an HDMI connector, a USB connector, an SD card connector, and / or an audio connector (headphone connector, etc.).

[0152] The haptic module ED79 can convert an electrical signal into a mechanical stimulus (e.g., vibration, movement, etc.) or an electrical stimulus that a user can sense through touch or kinesthesia. The haptic module ED79 can include a motor, a piezoelectric device, and / or an electrical stimulation device.

[0153] The camera module ED80 can capture still images and videos. The camera module ED80 can include a lens assembly having one or more lenses, the above image sensor 1000, an image signal processor, and / or a flash. The lens assembly included in the camera module ED80 can collect light emitted from an object (i.e., the object to be captured).

[0154] The power management module ED88 can manage the power supplied to the electronic device ED01. The power management module ED88 can be implemented as part of a power management integrated circuit (PMIC).

[0155] The battery ED89 can supply power to the components of the electronic device ED01. The battery ED89 can include a non-rechargeable primary battery, a rechargeable secondary battery, and / or a fuel cell.

[0156] The communication module ED90 can support establishing a direct (wired) communication channel and / or a wireless communication channel between the electronic device ED01 and another electronic device (e.g., the electronic device ED02, the electronic device ED04, the server ED08, etc.), and performing communication through the established communication channel. The communication module ED90 can operate independently of the processor ED20 (e.g., an application processor, etc.), and can include one or more communication processors that support direct communication and / or wireless communication. The communication module ED90 can include a wireless communication module ED92 (e.g., a cellular communication module, a short-range wireless communication module, a Global Navigation Satellite System (GNSS) communication module) and / or a wired communication module ED94 (e.g., a Local Area Network (LAN) communication module, a power line communication module, etc.). Among the communication modules, the corresponding communication module can communicate with another electronic device via a first network ED98 (e.g., a short-range communication network such as Bluetooth, WiFi Direct, or Infrared Data Association (IrDA)) or a second network ED99 (e.g., a long-range communication network such as a cellular network, the Internet, or a computer network (e.g., LAN, WAN, etc.)). These various types of communication modules described above can be integrated into one component (e.g., a single chip, etc.), or can be implemented as multiple separate components (e.g., multiple chips). The wireless communication module ED92 can identify and authenticate the electronic device ED01 in a communication network (e.g., the first network ED98 and / or the second network ED99) by using the subscriber information (e.g., International Mobile Subscriber Identifier (IMSI), etc.) stored in the subscriber identity module ED96.

[0157] The antenna module ED97 can transmit signals and / or power to the outside (another electronic device, etc.), or receive signals and / or power from the outside (another electronic device, etc.). The antenna can include a radiator formed as a conductive pattern formed on a substrate (e.g., a printed circuit board (PCB), a printed wiring board (PWB), etc.). The antenna module ED97 can include one or more antennas. When the antenna module ED97 includes multiple antennas, an antenna suitable for the communication type to be used in a communication network (e.g., the first network ED98 and / or the second network ED99) can be selected from the multiple antennas through the communication module ED90. Signals and / or power can be transmitted between the communication module ED90 and another electronic device via the selected antenna. Another component (e.g., a Radio Frequency Integrated Circuit (RFIC), etc.) other than the antenna can be included as part of the antenna module ED97.

[0158] Some components can be connected to each other via communication methods between peripheral devices (bus, General-Purpose Input and Output (GPIO), Serial Peripheral Interface (SPI), Mobile Industry Processor Interface (MIPI), etc.), and can exchange signals (e.g., commands, data, etc.).

[0159] Commands or data can be sent or received between the electronic device ED01 and an external electronic device ED04 via a server ED08 connected to a second network ED99. The other electronic devices ED02 and ED04 can be devices of the same or different types as the electronic device ED01. All or some of the operations performed in the electronic device ED01 can be performed in one or more of the other electronic devices ED02, ED04, and the server ED08. For example, when the electronic device ED01 has to perform a specific function or service, the electronic device ED01 can request one or more other electronic devices to perform some or all of the function or service instead of performing the function or service itself. The one or more electronic devices that receive the request perform additional functions or services related to the request and can transmit the execution results to the electronic device ED01. For this purpose, for example, cloud computing, distributed computing, or client-server computing technologies can be used.

[0160] Reference Figure 14 , the camera module ED80 can include a lens assembly 1170, a flash 1120, an image sensor 1000, an image stabilizer 1140, an AF controller 1130, a memory 1150 (buffer memory, etc.), an actuator 1180, and / or an Image Signal Processor (ISP) 1160.

[0161] The lens assembly 1170 can collect light emitted from an object to be captured. The lens assembly 1170 can include one or more optical lenses. The lens assembly 1170 can include a path switching member that switches the optical path toward the image sensor 1000. Depending on whether the path switching member is provided and the arrangement type of the optical lenses, the camera module ED80 can be of a vertical type or a folding type. The camera module ED80 can include a plurality of lens assemblies 1170, and in this case, the camera module ED80 can include a dual camera module, a 360-degree camera module, or a spherical camera module. Some of the plurality of lens assemblies 1170 can have the same lens characteristics (viewing angle, focal length, autofocus, F-number, optical zoom, etc.) or different lens characteristics. The lens assembly 1170 can include a wide-angle lens or a telephoto lens.

[0162] The actuator 1180 can drive the lens assembly 1170. At least some of the optical lenses and the path switching members included in the lens assembly 1170 can be moved by the actuator 1180. The optical lenses can be moved along the optical axis, and when the distance between adjacent lenses is adjusted by moving at least some of the optical lenses included in the lens assembly 1170, the optical zoom ratio can be adjusted.

[0163] The actuator 1180 can adjust the position of any one of the optical lenses in the lens assembly 1170 such that the image sensor 1000 can be located at the focal length of the lens assembly 1170. The actuator 1180 can drive the lens assembly 1170 according to the AF drive signal transmitted from the AF controller 1130.

[0164] The flash 1120 can emit light for enhancing the light emitted or reflected from an object. The flash 1120 can emit visible light or infrared light. The flash 1120 can include one or more light emitting diodes (red - green - blue (RGB) LEDs, white LEDs, infrared LEDs, ultraviolet LEDs, etc.) and / or xenon lamps. The image sensor 1000 can be the image sensor 1000 described above with reference to Figure 1 and can include any one of the nano - optical microlens arrays 130, 130A, 130B, 130C, 130D, and 130E of the above - described respective embodiments, or a combination or modified type thereof. The image sensor 1000 can obtain an image corresponding to the object by converting the light emitted or reflected from the object and transmitted through the lens assembly 1170 into an electrical signal.

[0165] In addition, each pixel of the image sensor 1000 can include, for example, a plurality of photosensitive units arranged in a 2×2 shape to form a plurality of channels. Some pixels can be used as AF pixels, and the image sensor 1000 can generate an AF drive signal based on signals from a plurality of channels in the AF pixels. As described above, among the nano - optical microlens arrays 130, 130A, 130B, 130C, 130D, or 130E included in the image sensor 1000, the nano - structure array type is set to improve AF performance and reduce crosstalk, and thus, the accuracy of AF drive can be improved.

[0166] In response to the movement of the camera module ED80 or the electronic device ED01 including the camera module ED80, the image stabilizer 1140 moves one or more lenses included in the lens assembly 1170 or the image sensor 1000 in a specific direction, or controls the operating characteristics (such as adjusting the readout timing) of the image sensor 1000 to compensate for the negative impact of the movement. The image stabilizer 1140 can sense the movement of the camera module ED80 or the electronic device ED01 by using a gyro sensor or an acceleration sensor arranged inside or outside the camera module ED80. The image stabilizer 1140 can be implemented as an optical type.

[0167] The AF controller 1130 can generate an AF drive signal based on the signal value sensed from the AF pixels in the image sensor 1000. The AF controller 1130 can control the actuator 1180 according to the AF drive signal.

[0168] The memory 1150 can store some or all of the data of the images obtained through the image sensor 1000 for subsequent image processing operations. For example, when multiple images are obtained at high speed, the obtained raw data (Bayer pattern data, high-resolution data, etc.) is stored in the memory 1150, and only low-resolution images are displayed. Then, the raw data of the selected image (user selection, etc.) can be transmitted to the image signal processor 1160. The memory 1150 can be integrated with the memory ED30 of the electronic device ED01, or can include an additional memory that operates independently.

[0169] The ISP 1160 can perform image processing on the images obtained through the image sensor 1000 or the image data stored in the memory 1150. The image processing can include depth map generation, 3D modeling, panoramic generation, feature extraction, image combination, and / or image compensation (noise reduction, resolution adjustment, brightness adjustment, blur, sharpening, softening, etc.). The image signal processor 1160 can control the components (such as the image sensor 1000) included in the camera module ED80 (exposure time control, readout timing control, etc.). The images processed by the image signal processor 1160 can be stored again in the memory 1150 for additional processing, or can be provided to external components of the camera module ED80 (such as the memory ED30, the display device ED60, the electronic device ED02, the electronic device ED04, the server ED08, etc.). The image signal processor 1160 can be integrated with the processor ED20, or can be configured as an additional processor that operates independently of the processor ED20. When the image signal processor 1160 is configured as an additional processor separated from the processor ED20, the images processed by the image signal processor 1160 undergo additional image processing by the processor ED20, and then can be displayed on the display device ED60.

[0170] The AF controller 1130 may be integrated with the image signal processor 1160. The image signal processor 1160 may generate an AF signal by processing signals of AF pixels from the image sensor 1000, and the AF controller 1130 may convert the AF signal into a driving signal for the actuator 1180 and transmit the signal to the actuator 1180.

[0171] The electronic device ED01 may further include one or more camera modules having different characteristics or functions. The camera module may include components similar to those of the camera module ED80 of Figure 14 and the image sensor included in the camera module may be implemented as a charge-coupled device (CCD) sensor and / or a complementary metal-oxide semiconductor (CMOS) sensor, and may include one or more sensors selected from image sensors having different characteristics (e.g., an RGB sensor, a black and white (BW) sensor, an IR sensor, or a UV sensor). In this case, one of the plurality of camera modules ED80 may include a wide-angle camera, and another camera module ED80 may include a telephoto camera. Similarly, one of the plurality of camera modules ED80 may include a front camera, and another camera module ED80 may include a rear camera.

[0172] The image sensor 1000 according to some embodiments may be applied to various electronic devices.

[0173] The image sensor 1000 according to some embodiments may be applied to a mobile phone or a smart phone, a tablet computer or a smart tablet computer, a digital camera or a video camera, a laptop computer, or a television or a smart TV. For example, a smart phone or a smart tablet computer may include a plurality of high-resolution cameras each including a high-resolution image sensor. By using the high-resolution camera, depth information of an object in an image may be extracted, defocus of the image may be adjusted, or an object in the image may be automatically recognized.

[0174] In addition, the image sensor 1000 may be applied to a smart refrigerator, a surveillance camera, a robot, a medical camera, etc. For example, the smart refrigerator may automatically recognize food in the refrigerator by using the image sensor and may notify a user of the presence of a specific type of food, the type of food put in or taken out, etc. via a smart phone. In addition, the surveillance camera may provide an ultra-high-resolution image and, by using high sensitivity, may allow a user to recognize an object or a person in the image even in a dark environment. The robot may be input into a disaster or industrial site where people may not be able to directly enter to provide a high-resolution image to a user. The medical camera may provide a high-resolution image for diagnosis or surgery and may dynamically adjust the field of view.

[0175] In addition, the image sensor 1000 can be applied to a vehicle. The vehicle may include a plurality of vehicle cameras arranged at various positions.

[0176] Each vehicle camera may include an image sensor according to an embodiment.

[0177] The vehicle can provide various information related to the interior or the surroundings of the vehicle to the driver by using the plurality of vehicle cameras, and can automatically identify objects or people in the images to provide information required for automatic travel.

[0178] The image sensor including the above-described nano-optical microlens array can exhibit improved autofocus performance and reduce crosstalk between adjacent pixels.

[0179] The image sensor including the above-described nano-optical microlens array can reduce performance degradation according to the chief ray angle.

[0180] The above exemplary embodiments are merely exemplary and should not be construed as limiting. The present teachings can be easily applied to other types of devices. In addition, the description of the exemplary embodiments is intended to be illustrative and not to limit the scope of the claims, and many alternatives, modifications, and variations will be apparent to those skilled in the art.

Claims

1. An image sensor, comprising: a sensor substrate including a plurality of pixels configured to sense incident light; A nano-optical micro-lens array, comprising a plurality of nano-optical micro-lenses corresponding to the plurality of pixels respectively; as well as A color filter array is disposed between the sensor substrate and the nano-optical microlens array and includes a plurality of color filters, Each of the plurality of nano-optical microlenses comprises a plurality of nanostructures for converging the incident light onto a corresponding pixel, and A filling factor represents a ratio of an area of ​​a nanostructure arranged within a reference circle among the plurality of nanostructures included in one of the plurality of nano-optical microlenses to an entire area of ​​the plurality of nanostructures included in the one nano-optical microlens, and the reference circle has a size of a pixel corresponding to the one nano-optical microlens as a diameter, and the filling factor is greater than or equal to 95%.

2. The image sensor according to claim 1, wherein: Among the plurality of nano-optical micro-lenses, the filling factor of the nano-optical micro-lens located at the most central point of the nano-optical micro-lens array is 100%.

3. The image sensor according to claim 1, wherein: Each of the plurality of pixels includes four photosensitive cells arranged in a 2×2 manner.

4. The image sensor according to claim 1, wherein: The plurality of nanostructures are arranged on a two-dimensional plane perpendicular to a direction in which the sensor substrate, the color filter array, and the nano-optical microlens array are arranged, and When the plurality of nanostructures are arranged in the form of an N×N matrix on the two-dimensional plane, the plurality of nanostructures do not exist at one or more of the four positions (1, 1), (1, N), (N, 1) and (N, N). Wherein, N is an integer greater than or equal to 3.

5. The image sensor according to claim 4, wherein: Among the plurality of nano-optical microlenses, the plurality of nanostructures included in the nano-optical microlens located at the center of the nano-optical microlens array do not exist at the four positions (1, 1), (1, N), (N, 1) and (N, N) of the N×N matrix, and occupy the remaining N 2 -4 positions.

6. The image sensor according to claim 4, wherein: When the plurality of nano-optical micro-lenses are divided into a center and a periphery according to relative positions within the nano-optical micro-lens array, The plurality of nanostructures included in one nano-optical microlens located at the periphery are arranged in a row or a column in an order of increasing size toward the center.

7. The image sensor according to claim 4, wherein: When the plurality of nano-optical micro-lenses are divided into a center and a periphery according to relative positions within the nano-optical micro-lens array, Among the nano-optical microlenses belonging to the periphery, in two nano-optical microlenses having different azimuth angles defined in the two-dimensional plane, there is no difference in the position of the nanostructure among the four positions (1, 1), (1, N), (N, 1) and (N, N).

8. The image sensor according to claim 4, wherein: When the plurality of nano-optical micro-lenses are divided into a center and a periphery according to relative positions within the nano-optical micro-lens array, Among the nano-optical microlenses belonging to the periphery, in the nano-optical microlenses having an azimuth angle of 0 degrees defined in the two-dimensional plane, the nanostructure does not exist at positions (1, N) and (N, N).

9. The image sensor according to claim 4, wherein: When the plurality of nano-optical micro-lenses are divided into a center and a periphery according to relative positions within the nano-optical micro-lens array, Among the nano-optical microlenses belonging to the periphery, in the nano-optical microlenses having an azimuth angle of 90 degrees defined in the two-dimensional plane, the nanostructure does not exist at positions (1, 1) and (1, N).

10. The image sensor according to claim 4, wherein: When the plurality of nano-optical micro-lenses are divided into a center and a periphery according to relative positions within the nano-optical micro-lens array, Among the nano-optical microlenses belonging to the periphery, in the nano-optical microlenses having an azimuth angle of 180 degrees defined in the two-dimensional plane, the nanostructure does not exist at positions (1, 1) and (N, 1).

11. The image sensor according to claim 4, wherein: When the plurality of nano-optical micro-lenses are divided into a center and a periphery according to relative positions within the nano-optical micro-lens array, Among the nano-optical microlenses belonging to the periphery, in the nano-optical microlenses having an azimuth angle of 270 degrees defined in the two-dimensional plane, the nanostructure does not exist at positions (N, 1) and (N, N).

12. The image sensor according to claim 1, wherein: When the plurality of nano-optical microlenses are divided into a center and a periphery according to relative positions within the nano-optical microlens array, the filling factor of the nano-optical microlenses at the center is greater than the filling factor of the nano-optical microlenses at the periphery.

13. The image sensor according to claim 1, wherein: The plurality of nano-optical micro-lenses include: The first nano-optical microlens, facing the green filter; a second nano-optical microlens facing the blue filter; and The third nano-optical microlens faces the red filter.

14. The image sensor according to claim 13, wherein: A filling factor of the second nano-optical microlens is smaller than a filling factor of the first nano-optical microlens or the third nano-optical microlens.

15. The image sensor according to claim 13, wherein: The number of nanostructures included in the second nano-optical microlens is greater than the number of nanostructures included in the first nano-optical microlens or the third nano-optical microlens.

16. The image sensor according to claim 1, wherein: The plurality of pixels include first to fourth pixel groups that are adjacent to each other in a 2×2 arrangement, The first pixel group to the fourth pixel group respectively include four first pixels to four fourth pixels that are adjacent to each other in a 2×2 arrangement, The plurality of nano-optical microlenses include four first to four fourth nano-optical microlenses respectively corresponding to the four first to four fourth pixels adjacent to each other in a 2×2 arrangement, The color filter array includes a first green filter, a blue filter, a red filter, and a second green filter, and The first green filter, the blue filter, the red filter, and the second green filter face the first to fourth pixel groups one by one, respectively.

17. The image sensor according to claim 1, wherein: The plurality of pixels include first to fourth pixels that are adjacent to each other in a 2×2 arrangement, Each of the first to fourth pixels includes four photosensitive units arranged in 2×2, The plurality of nano-optical micro-lenses include first to fourth nano-optical micro-lenses facing the first to fourth pixels respectively. The color filter array includes a first green filter, a blue filter, a red filter, and a second green filter, and The first green filter, the blue filter, the red filter, and the second green filter face the first to fourth pixels one by one, respectively.

18. An electronic device comprising: a lens assembly including one or more lenses for forming an optical image of a subject; The image sensor according to claim 1, wherein the image sensor is configured to convert the optical image into an electrical signal; as well as A processor is configured to process the electrical signal generated by the image sensor.

19. An image sensor, comprising: a sensor substrate including a plurality of pixels configured to sense incident light; A nano-optical micro-lens array, comprising a plurality of nano-optical micro-lenses corresponding to the plurality of pixels respectively; as well as A color filter array is disposed between the sensor substrate and the nano-optical microlens array and includes a plurality of color filters, Each of the plurality of nano-optical microlenses comprises a plurality of nanostructures for converging the incident light onto a corresponding pixel, When the plurality of nanostructures are arranged in the form of an N×N matrix on a two-dimensional plane, in the nano-optical microlens disposed at the center of the nano-optical microlens array, the plurality of nanostructures are not present at four positions (1, 1), (1, N), (N, 1) and (N, N), and are disposed at the remaining N 2 - 4 positions, and Wherein, N is an integer greater than or equal to 3.

20. An image sensor, comprising: a sensor substrate including pixels configured to convert light into electrical signals; a nano-optical microlens array comprising nano-optical microlenses for focusing light into said pixels; as well as A color filter array is located between the sensor substrate and the nano-optical microlens array, Each of the nano-optical microlenses includes a nanostructure, which is arranged along the circumference of two concentric circles with different diameters and is located away from a pixel boundary line and the center of the concentric circles.

Images