Image sensor

Abstract

To provide an image sensor which prevents crosstalk from occurring in an autofocusing pixel, improves sensitivity of a pixel adjacent to the autofocusing pixel, and generates images having improved image quality.SOLUTION: An image sensor includes: a substrate, having first and second surfaces opposing each other in a first direction, on which a plurality of unit pixels are arranged, the plurality of unit pixels including at least one normal pixel, an autofocusing pixel, and a compensation pixel in a direction parallel to the first surface; a photodiode disposed in the substrate in each of the plurality of unit pixels; and a device isolation film disposed between the plurality of unit pixels. The unit pixels are arranged on the first surface and include color filters separated from each other by a grid, and microlenses disposed on the color filters. The normal pixel includes a normal microlens. The compensation pixel is disposed on one side of the autofocusing pixel and includes a transparent color filter and a compensation microlens smaller than the normal microlens.SELECTED DRAWING: Figure 3a

Description

Technical Field

[0001] The present invention relates to an image sensor, and particularly to an image sensor that prevents crosstalk, improves the sensitivity of pixels adjacent to autofocus pixels, and generates an image with improved image quality.

Background Art

[0002] An image sensor is a semiconductor-based sensor that receives light and generates an electrical signal, and includes a pixel array having a plurality of unit pixels, a circuit for driving the pixel array to generate an image, and the like. The plurality of unit pixels include a photodiode that generates electric charge in response to external light, a pixel circuit that converts the electric charge generated by the photodiode into an electrical signal, and the like. Image sensors can be widely applied to cameras for taking photos and videos, as well as smartphones, tablet PCs, laptop computers, TVs, automobiles, and the like.

[0003] In recent years, along with research to improve autofocus performance, research to generate an image with high image quality has become an issue.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] The present invention has been made in view of the problems of the above-mentioned conventional image sensors, and the object of the present invention is to provide an image sensor that prevents crosstalk that may occur in the autofocus pixels of an image sensor including a transparent color filter, improves the sensitivity of pixels adjacent to the autofocus pixels, and further generates an image with improved image quality. [Means for solving the problem]

[0006] To achieve the above objective, the present invention provides an image sensor comprising: a substrate having a first surface and a second surface facing each other in a first direction, on which a plurality of unit pixels are arranged along a direction parallel to the first surface, including at least one general pixel, at least one autofocus pixel, and at least one compensation pixel; a photodiode disposed inside the substrate in each of the plurality of unit pixels; and an element isolation film disposed between the plurality of unit pixels. The autofocus pixels include a pair of unit pixels arranged parallel to a second direction perpendicular to the first direction, Each of the plurality of unit pixels includes a color filter arranged on the first plane and separated from each other by a grid, and a microlens arranged on the color filter, the general pixel includes a general microlens, and the compensation pixel is In the second direction in which the pair of unit pixels are arranged in parallel, The autofocus pixels Adjacent to only one side It includes a transparent color filter and a compensating microlens smaller than the general microlens. Furthermore, by including the compensating microlenses which are smaller than the general microlenses included in the general pixels, the asymmetric output occurring in the pair of unit pixels included in the autofocus pixels is compensated. It is characterized by the following:

[0007] Furthermore, the image sensor according to the present invention, made to achieve the above objective, comprises a substrate, a pixel array including a plurality of pixel groups arranged along a direction parallel to the upper surface of the substrate, and a logic circuit for acquiring pixel signals from the pixel array, wherein each of the plurality of pixel groups is defined by an element isolation film extending in a first direction perpendicular to the upper surface of the substrate. at least one Autofocus pixels, at least one Compensation pixels, and at least one General pixels includingThe unit pixel comprises a plurality of unit pixels, each of which includes a photodiode disposed inside the substrate, a color filter disposed on the upper surface of the substrate and separated from adjacent color filters by a grid, and a microlens disposed on the color filter, wherein the compensation pixel compensates for the signal output from the autofocus pixel and includes a compensation microlens smaller than the microlens contained in the adjacent pixel, and a transparent color filter. Furthermore, the pair of unit pixels included in the autofocus pixel are arranged parallel to each other in a second direction perpendicular to the first direction, and the compensation pixel is arranged adjacent only to one side of the autofocus pixel in the second direction in which the pair of unit pixels are arranged parallel to each other. It is characterized by the following:

[0008] Furthermore, the image sensor according to the present invention, made to achieve the above objective, comprises a substrate including a first surface and a second surface facing each other in a first direction, a plurality of unit pixels arranged on the substrate, a photodiode disposed inside the substrate in each of the unit pixels, and an element isolation film disposed between the unit pixels, each of the unit pixels forming an autofocus pixel, a general pixel, and a compensation pixel, and includes a color filter disposed on the first surface and separated from adjacent color filters by a grid, and a microlens disposed on the color filter, the autofocus pixel includes a pair of the unit pixels arranged parallel to a second direction perpendicular to the first direction, and the pair of unit pixels share the microlens and the color filter, The compensation pixel has a different structure from the general pixel. In the second direction in which the pair of unit pixels are arranged in parallel, the following are arranged adjacent only to one side of the autofocus pixel: The system includes a transparent color filter and is characterized by compensating the signal output from the autofocus pixel. [Effects of the Invention]

[0009] According to the image sensor of the present invention, a compensation pixel adjacent to an autofocus pixel and including a transparent color filter can include a small microlens and grid, thereby improving crosstalk in the autofocus pixel and sensitivity in the compensation pixel. Further, it can include pixels including microlenses and grids that are formed smaller as going from the center to the end of the pixel array, thereby improving lens shading along with the problem of crosstalk.

Brief Description of the Drawings

[0010] [Figure 1] It is a block diagram showing a schematic configuration of an image sensor according to an embodiment of the present invention. [Figure 2] It is a circuit diagram showing a pixel circuit of an image sensor according to an embodiment of the present invention. [Figure 3a] It is a plan view for explaining a pixel group included in an image sensor according to an embodiment of the present invention. [Figure 3b] It is a plan view for explaining a pixel group included in an image sensor according to an embodiment of the present invention. [Figure 4] It is a cross-sectional view for explaining an image sensor according to an embodiment of the present invention, and is a cross-sectional view taken along the line I-I' in FIG. 3a. [Figure 5] It is a plan view for explaining a pixel group included in an image sensor according to an embodiment of the present invention. [Figure 6] It is a plan view for explaining a pixel group included in an image sensor according to an embodiment of the present invention. [Figure 7] It is a plan view for explaining a pixel group included in an image sensor according to an embodiment of the present invention. [Figure 8] It is a plan view for explaining a pixel array included in an image sensor according to an embodiment of the present invention. [Figure 9] It is a plan view for explaining an image sensor according to an embodiment of the present invention. [Figure 10] It is a view for explaining an image sensor according to an embodiment of the present invention, and is a cross-sectional view taken along the line II-II' in FIG. 9. [Figure 11]It is a plan view for explaining an image sensor according to an embodiment of the present invention. [Figure 12] It is a view for explaining an image sensor according to an embodiment of the present invention, and is a cross-sectional view taken along line III-III' of FIG. 11. [Figure 13] It is a plan view for explaining a pixel array included in an image sensor according to an embodiment of the present invention. [Figure 14] It is a cross-sectional view for explaining a pixel array included in an image sensor according to an embodiment of the present invention, and is a cross-sectional view taken along line IV-IV' of FIG. 13. [Figure 15] It is a plan view for explaining a pixel array included in an image sensor according to an embodiment of the present invention. [Figure 16] It is a cross-sectional view for explaining a pixel array included in an image sensor according to an embodiment of the present invention, and is a cross-sectional view taken along line V-V' of FIG. 15. [Figure 17a] It is a cross-sectional view for explaining a formation process of an image sensor according to an embodiment of the present invention. [Figure 17b] It is a cross-sectional view for explaining a formation process of an image sensor according to an embodiment of the present invention. [Figure 17c] It is a cross-sectional view for explaining a formation process of an image sensor according to an embodiment of the present invention. <00'00108> [Figure 17d] It is a cross-sectional view for explaining a formation process of an image sensor according to an embodiment of the present invention. [Figure 17e] It is a cross-sectional view for explaining a formation process of an image sensor according to an embodiment of the present invention. [Figure 17f] It is a cross-sectional view for explaining a formation process of an image sensor according to an embodiment of the present invention. [Figure 18] It is a block diagram showing a schematic configuration of an electronic device including an image sensor according to an embodiment of the present invention. [Figure 19] It is a block diagram showing a schematic configuration of the camera module of FIG. 18. [Modes for carrying out the invention]

[0011] Next, specific examples of embodiments for implementing the image sensor according to the present invention will be described with reference to the drawings.

[0012] Figure 1 is a block diagram showing a schematic configuration of an image sensor according to one embodiment of the present invention. Referring to Figure 1, an image sensor 1 according to one embodiment of the present invention includes a pixel array 10 and a logic circuit 20, etc.

[0013] The pixel array 10 includes multiple unit pixels PX arranged in the form of an array along multiple rows and multiple columns. Each unit pixel PX includes at least one photoelectric element that generates an electric charge in response to light, and a pixel circuit that generates a pixel signal corresponding to the charge generated by the photoelectric element. Photoelectric conversion elements include photodiodes formed from semiconductor materials, and / or organic photodiodes formed from organic materials. In one embodiment, each unit pixel PX includes one photoelectric element, and the photoelectric element included in the unit pixel PX receives light and generates an electric charge.

[0014] In one embodiment of the present invention, a plurality of unit pixels PX include at least one general pixel, at least one autofocus pixel, and at least one compensation pixel. Autofocus pixels are pixels that enable the image sensor 1 to perform the autofocus function, and compensation pixels are pixels that prevent crosstalk that may occur in the autofocus pixels. On the other hand, each general pixel, autofocus pixel, and compensation pixel contains a photodiode that receives light and generates an electric charge. However, this is only one embodiment, and is not limited thereto.

[0015] In the embodiment, the pixel circuit includes a transmission transistor, a drive transistor, a selection transistor, and a reset transistor, among others. If each unit pixel PX has one photoelectric element, then each unit pixel PX includes a pixel circuit for processing the charge generated by the photoelectric element. As an example, each of the multiple unit pixels PX included in the image sensor 1 according to one embodiment of the present invention includes a photodiode. As a result, the pixel circuit corresponding to each unit pixel PX includes a transmission transistor, a drive transistor, a selection transistor, and a reset transistor.

[0016] However, this is only one embodiment, and is not limited thereto. For example, multiple unit pixels PX included in the image sensor 1 can share a floating diffusion region in units of pixel groups or smaller units, thereby allowing at least some of the photoelectric conversion elements to share some of the drive transistors, selection transistors, and reset transistors.

[0017] The logic circuit 20 includes a circuit for controlling the pixel array 10. For example, the logic circuit 20 includes a low driver 21, a readout circuit 22, a column driver 23, and control logic 24. The row driver 21 drives the pixel array 10 row by row. For example, the low driver 21 generates transmission control signals to control the transmission transistors of the pixel circuit, reset control signals to control the reset transistors, and selection control signals to control the selection transistors, and inputs them to the pixel array 10 row by row.

[0018] The readout circuit 22 may include a Correlated Double Sampler (CDS), an Analog-to-Digital Converter (ADC), and the like. The correlated dual sampler is connected via unit pixels (PX) and column lines. The correlated double sampler performs correlated double sampling by receiving pixel signals from unit pixels PX connected to the low line selected by the low line selection signal of the low driver 21. The pixel signal is received via the column line. The analog-to-digital converter converts the pixel signals detected by the correlated duplex sampler into digital pixel signals and transmits them to the column driver 23.

[0019] The column driver 23 includes a latch or buffer circuit and an amplification circuit for temporarily storing the digital pixel signal, and processes the digital pixel signal received from the readout circuit 22. The low driver 21, the readout circuit 22, and the column driver 23 are controlled by the control logic 24. The control logic 24 includes a timing controller for controlling the operating timing of the low driver 21, the readout circuit 22, and the column driver 23.

[0020] Within a given unit pixel (PX), unit pixels (PX) located at the same position horizontally share the same column line. For example, unit pixels PX arranged at the same position in the vertical direction are simultaneously selected by the low driver 21 and output pixel signals via the column line. In one embodiment, the readout circuit 22 simultaneously acquires a pixel signal from a unit pixel PX selected by the low driver 21 via a column line. The pixel signal includes a reset voltage and a pixel voltage, where the pixel voltage is the voltage in which the charge generated in response to light at each unit pixel PX is reflected in the reset voltage. However, the explanation detailed with reference to Figure 1 is not limited thereto, and the image sensor may further include other configurations and be driven in a variety of ways.

[0021] Figure 2 is a circuit diagram showing the pixel circuit of an image sensor according to one embodiment of the present invention. Referring to Figure 2, the multiple unit pixels PX included in the image sensor 1 according to one embodiment of the present invention are grouped in pairs. Each pixel circuit corresponding to a grouped unit pixel PX includes multiple semiconductor elements for processing the charge generated by the photodiodes (PD1, PD2), along with multiple photodiodes (PD1, PD2) corresponding to multiple unit pixels PX.

[0022] As an example, the pixel circuit includes first and second photodiodes (PD1, PD2), first and second transmission transistors (TX1, TX2), a reset transistor RX, a selection transistor SX, and a drive transistor DX. The first and second photodiodes (PD1, PD2) included in the pixel circuit share a floating diffusion region FD, a reset transistor RX, a selection transistor SX, and a drive transistor DX. On the other hand, the gate electrodes of the first and second transmission transistors (TX1, TX2), the reset transistor RX, and the selection transistor SX are connected to the drive signal lines (TG1, TG2, RG, SG), respectively. However, this is only one embodiment and is not limited to what is shown in Figure 2; pixel circuits can be designed in a variety of ways. For example, a pixel circuit may include a semiconductor element for processing the charge generated by a photodiode, on a unit pixel (PX) basis.

[0023] In one embodiment of the present invention, one pixel circuit generates a first electrical signal from the charge generated by the photodiodes (PD1, PD2) contained in that pixel circuit and outputs it to the first column line, and the other pixel circuit generates a second electrical signal from the charge generated by the photodiodes (PD1, PD2) contained in that pixel circuit and outputs it to the second column line. In one embodiment, two or more pixel circuits arranged adjacent to each other share a single first column line. Similarly, two or more other pixel circuits that are adjacent to each other share one second column line. Pixel circuits that are placed adjacent to each other share some semiconductor elements.

[0024] The first and second transmission transistors (TX1 and TX2) are connected to the first and second transmission gates (TG1 and TG2) and the first and second photodiodes (PD1 and PD2), respectively. On the other hand, the first and second transmission transistors (TX1 and TX2) share a floating diffusion region (FD). The first and second photodiodes (PD1 and PD2) generate charge in proportion to the amount of light incident from the outside, and accumulate it in each photodiode.

[0025] The first and second transmission transistors (TX1, TX2) sequentially transmit the charge accumulated in the first and second photodiodes (PD1, PD2) to the floating diffusion region FD. Different signals are applied to the first and second transmission gates (TG1 and TG2) in order to transmit the charge generated by one of the first and second photodiodes (PD1 and PD2) to the floating diffusion region FD. As a result, the floating diffusion region FD accumulates the charge generated in either the first or second photodiode (PD1, PD2).

[0026] The reset transistor RX periodically resets the charge accumulated in the floating diffusion region FD. As an example, the electrodes of the reset transistor RX are connected to the floating diffusion region FD and the power supply voltage V. DD It connects to the network. When the reset transistor RX is turned on, the power supply voltage V DD Due to the potential difference, the charge accumulated in the floating diffusion region FD is discharged, resetting the floating diffusion region FD, and the voltage in the floating diffusion region FD becomes the power supply voltage V DD It becomes identical to this.

[0027] The operation of the drive transistor DX is controlled according to the amount of charge accumulated in the floating diffusion region FD. The drive transistor DX, in combination with a current source located outside the unit pixel PX, functions as a source follower buffer amplifier. As an example, the potential change due to charge accumulation in the floating diffusion region (FD) is amplified and output to the output line Vout.

[0028] The selection transistor SX selects the unit pixels PX to be read, row by row. When the selection transistor SX is turned on, the electrical signal output from the drive transistor DX is transmitted to the selection transistor SX.

[0029] An image sensor 1 according to one embodiment of the present invention provides an autofocus function based on the pixel circuit shown in Figure 2, wherein at least one of a pixel group containing multiple unit pixels that share a floating diffusion region FD provides an autofocus function. As an example, the image sensor 1 provides an autofocus function in one direction using a first photodiode PD1 and a second photodiode PD2. For example, the logic circuit provides an autofocus function in the left-right direction using the first pixel signal acquired after the first transmission transistor TX1 is turned on, and the second pixel signal acquired after the second transmission transistor TX2 is turned on. However, the pixel circuit for the unit pixel that provides the autofocus function is not necessarily limited to that shown in Figure 2, and some elements may be added or omitted as needed.

[0030] Figures 3a and 3b are plan views illustrating a pixel group included in an image sensor according to one embodiment of the present invention. Figures 3a and 3b show a pixel group PG corresponding to one color filter array included in an image sensor (100-1, 100-2) according to one embodiment of the present invention, and its configuration. As an example, one color filter array corresponds to four pixel groups PG, and in a first direction (e.g., the Z direction), each pixel group PG includes a color filter CF having a predetermined hue.

[0031] Referring to Figures 3a and 3b, in an image sensor (100-1, 100-2) according to one embodiment of the present invention, each pixel group PG includes a plurality of unit pixels PX arranged in a "2×2" configuration. On the other hand, in the embodiments shown in Figures 3a and 3b, each pixel group PG includes a colored color filter and a transparent color filter. For example, in each pixel group PG, the colored color filter and the transparent color filter are arranged alternately in a second direction perpendicular to the first direction (e.g., the X direction) and in a third direction perpendicular to both the first and second directions (e.g., the Y direction).

[0032] Each pixel group PG contains multiple unit pixels PX, which are defined by element isolation films DTI placed between them, and grids GR are placed on the element isolation films DTI. Each of the multiple unit pixels PX separated by the element isolation film DTI includes a photodiode and a microlens ML positioned above the color filter CF. The microlens ML is positioned at the top of the unit pixel PX in the first direction and allows light to enter it.

[0033] A plurality of unit pixels PX included in an image sensor (100-1, 100-2) according to one embodiment of the present invention include at least one general pixel PX1, at least one autofocus pixel PX2, and at least one compensation pixel PXC. For example, the general pixel PX1 and the compensated pixel PXC are pixels used to generate an image using the acquired pixel signal, while the autofocus pixel PX2 is a pixel used to automatically focus on a subject using the phase difference of the incident light. On the other hand, the compensation pixel PXC is a pixel designed to prevent crosstalk that may occur in the autofocus pixel PX2.

[0034] The autofocus pixel PX2 includes a pair of unit pixels PX arranged parallel to each other in a second or third direction. For example, the image sensor (100-1) shown in Figure 3a includes an autofocus pixel PX2 composed of two unit pixels PX arranged parallel to each other in a third direction. Furthermore, the image sensor (100-2) shown in Figure 3b includes an autofocus pixel PX2 composed of two unit pixels PX arranged parallel to each other in the second direction. On the other hand, the compensation pixel PXC is positioned on one side of the autofocus pixel PX2 in the direction in which the two unit pixels PX included in the autofocus pixel PX2 are arranged.

[0035] Referring to Figure 3a, a pair of unit pixels PX contained in the autofocus pixel PX2 are contained in one pixel group PG. In contrast, referring to Figure 3b, the pair of unit pixels PX included in the autofocus pixel PX2 spans two adjacent pixel groups PG.

[0036] In an image sensor (100-1, 100-2) according to one embodiment of the present invention, each pixel group PG includes a colored color filter CF having at least one hue from green G, red R, and blue B, and a transparent W color filter CF. As an example, the image sensors (100-1, 100-2) shown in Figures 3a and 3b include green G, red R, blue B, and transparent W color filters CF.

[0037] On the other hand, the image sensors (100-1, 100-2) include one color filter array for each pixel group PG, which is arranged in a "2x2" configuration. For example, a pixel group PG containing a green G color filter is arranged alternately with a pixel group PG containing a red R or blue B color filter in the second and third directions. However, unlike other unit pixels PX, the autofocus pixel PX2, which performs the autofocus function, utilizes the phase difference of light incident on an adjacent pair of unit pixels, and therefore has a colored filter CF of the same hue placed adjacent to it.

[0038] In other words, a pixel group PG consisting only of general pixels PX1 and compensating pixels PXC within the pixel group PG includes two non-adjacent transparent color filters CF and two non-adjacent colored color filters CF. However, this is only one embodiment, and the color filter array of the image sensors (100-1, 100-2) is not limited to those shown in Figures 3a and 3b.

[0039] In an image sensor (100-1, 100-2) according to one embodiment of the present invention, a general pixel PX1 includes a general microlens ML1 placed on a colored or transparent color filter CF, and a general grid GRN that separates the color filter CF from other adjacent color filters CF. The autofocus pixel PX2 includes an autofocus microlens ML2 shared by a pair of unit pixels PX contained within the autofocus pixel PX2, a color filter CF shared by the pair of unit pixels PX, and a general grid GRN. On the other hand, the compensation pixel PXC includes a compensation microlens MLC and a compensation grid GRC, which are positioned on a transparent color filter CF.

[0040] As described above, an image sensor (100-1, 100-2) according to one embodiment of the present invention includes a transparent color filter CF. At least one of the unit pixels PX located on one side of the autofocus pixel PX2 includes a transparent color filter CF, and the autofocus function of the image sensor (100-1, 100-2) performed by the autofocus pixel PX2 may be affected by the unit pixel PX including the transparent color filter CF.

[0041] For example, around one of the pair of unit pixels PX included in the autofocus pixel PX2, a unit pixel PX containing a colored color filter CF is arranged, and around the other unit pixel PX included in the pair of unit pixels PX included in the autofocus pixel PX2, a unit pixel PX containing a transparent color filter CF is arranged. This can cause the pair of unit pixels PX contained within the autofocus pixel PX2 to produce an asymmetrical output. Such asymmetrical output may cause crosstalk problems in the autofocus pixel PX2 and may also degrade the autofocus capabilities of the image sensors (100-1, 100-2).

[0042] In an image sensor (100-1, 100-2) according to one embodiment of the present invention, the above problem can be solved by forming a unit pixel PX adjacent to the autofocus pixel PX2 and including a transparent color filter CF as a compensation pixel PXC. The compensating pixel PXC includes a compensating microlens MLC, which is smaller in size than the general microlens ML1 included in the general pixel PX1, thereby compensating for the asymmetric output occurring in the pair of unit pixels PX included in the autofocus pixel PX2. As a result, the image sensors (100-1, 100-2) can perform improved autofocus compared to when they do not include the PXC (compensated pixels).

[0043] On the other hand, the compensating microlens MLC included in the compensating pixel PXC is smaller in size than the general microlens ML1, which may result in a loss of sensitivity in the compensating pixel PXC. An image sensor according to one embodiment of the present invention (100-1, 100-2) can minimize sensitivity loss by increasing the aperture area of ​​the pixels by forming the compensation grid GRC surrounding the transparent color filter CF included in the compensation pixel PXC smaller than the general grid GRN.

[0044] Figure 4 is a cross-sectional view illustrating an image sensor according to one embodiment of the present invention, and is a cross-sectional view obtained by cutting the image sensor (100-1) shown in Figure 3a along the line I-I'. Referring to Figure 4, the image sensor (100-1) includes a substrate 110 including a first surface 111 and a second surface 112 facing each other, a photodiode PD disposed inside the substrate 110 in each of the multiple unit pixels PX, and an element isolation film DTI disposed between the multiple unit pixels PX.

[0045] As an example, a group of unit pixels PX includes at least one general pixel PX1, at least one autofocus pixel PX2, and at least one compensation pixel PXC, all arranged along a direction parallel to the first surface 111.

[0046] In a general pixel PX1 included in an image sensor (100-1) according to one embodiment of the present invention, a color filter CF, a light transmission layer 130, and a general microlens ML1 are sequentially arranged on the first surface 111 of the substrate 110. As an example, in the image sensor (100-1) shown in Figure 4, the color filter CF included in the general pixel PX1 is blue B. However, this is only one embodiment, and is not limited thereto. Light incident through the general microlens ML1 is incident on the photodiode PD contained in the general pixel PX1. As described above, the general pixel PX1 of the image sensor (100-1) according to one embodiment of the present invention generates an image using the corresponding general microlens ML1 and photodiode PD.

[0047] On the other hand, in the autofocus pixel PX2 included in the image sensor (100-1), a color filter CF corresponding to the autofocus pixel PX2, a light transmission layer 130, and an autofocus microlens ML2 are sequentially arranged on the first surface 111 of the substrate 110. As an example, in the image sensor (100-1) shown in Figure 4, the color filter CF included in the autofocus pixel PX2 is green G, and the autofocus microlens ML2 has a configuration that extends in a third direction (e.g., the Y direction) to correspond to the autofocus pixel PX2. However, this is only one embodiment, and is not limited thereto.

[0048] In the compensation pixel PXC included in the image sensor (100-1), a transparent color filter CF, a light transmission layer 130, and a compensation microlens MLC are sequentially arranged on the first surface 111 of the substrate 110. The compensating microlens MLC is smaller in size than the general microlens ML1. For example, the compensating microlens MLC has the same refractive index as the general microlens ML1, but with a smaller diameter.

[0049] Referring to both Figure 3a and Figure 4, the color filters CF included in the image sensor (100-1) are separated from each other by grids GR placed on the element isolation film DTI. Grid GR may contain metal or transparent material. The image sensor 100-1 shown in Figure 4 is an example of a grid GR containing a transparent material.

[0050] On the other hand, some of the grid GRs included in the image sensor (100-1) have different sizes from each other. As an example, in the image sensor (100-1), the grid GR includes a general grid GRN and a compensation grid GRC. However, this is only one embodiment and is not limited thereto; the image sensor (100-1) may include grids GR of various sizes as needed.

[0051] In an image sensor (100-1) according to one embodiment of the present invention, a transparent color filter CF included in a compensation pixel PXC is separated from other adjacent color filters CF by a compensation grid GRC. On the other hand, the color filters CF included in the general pixel PX1 and the autofocus pixel PX2 are separated from other adjacent color filters CF by a general grid GRN which is larger than the compensation grid GRC. As an example, the compensating grid GRC has a shorter length than the general grid GRN in all directions.

[0052] In an image sensor (100-1) according to one embodiment of the present invention, the size of the grid GR arranged between pixels of different types corresponds to the size of the smaller microlens ML among the microlenses ML contained between two adjacent pixels. As an example, the grid GR positioned between the compensating pixel PXC and the general pixel PX1 corresponds to the size of the smaller of the two compensating microlenses, MLC and ML1. Therefore, a compensation grid GRC is placed between the compensation pixel PXC and the general pixel PX1. However, this is only one embodiment, and is not limited thereto.

[0053] Due to the difference in grid size GR, the aperture of the general pixel PX1 is smaller than the aperture of the compensated pixel PXC. In other words, in a direction parallel to the first direction, the color filter CF included in the general pixel PX1 has a shorter length than the color filter CF included in the compensating pixel PXC. As an example, in the image sensor (100-1) shown in Figure 4, the length of the color filter CF included in the general pixel PX1 is L1, and the length of the color filter CF included in the compensation pixel PXC is Lc, which is greater than L1.

[0054] An image sensor (100-1) according to one embodiment of the present invention minimizes sensitivity loss that may occur due to the size of the compensating microlens MLC by forming the aperture of the compensating pixel PXC to be larger than the aperture of other pixels.

[0055] On the other hand, in the image sensor (100-1), a pixel circuit is located below the photodiode PD. As an example, a pixel circuit includes a wiring pattern 170 and an insulating layer 180 covering the wiring pattern 170, and is arranged on the second surface 112 of the substrate 110. Although not shown in Figure 4, the pixel circuit includes multiple elements, including transmission transistors, and a floating diffusion region. The pixel circuit operates to acquire pixel signals from multiple unit pixels PX.

[0056] Figures 5 to 7 are plan views illustrating the pixel groups included in an image sensor according to one embodiment of the present invention. As described above, each pixel group PG in the image sensor 100 according to one embodiment of the present invention includes a colored color filter CF having at least one hue from green G, red R, and blue B, and a transparent W color filter CF.

[0057] Referring to Figure 5, an image sensor 200 according to one embodiment of the present invention includes a plurality of unit pixels PX, including at least one general pixel PX1, at least one autofocus pixel PX2, and at least one compensation pixel PXC, similar to the image sensor (100-1) shown in Figure 3a, and each pixel includes a corresponding microlens ML and grid GR.

[0058] As an example, each pixel group PG in the image sensor 200 includes two non-adjacent transparent color filters CF and two non-adjacent colored color filters CF. In the image sensor 200, the colored color filter CF includes a red R or blue B color filter and a green G color filter. On the other hand, pixel group PG containing a red R color filter and pixel group PG containing a blue B color filter are arranged alternately in the second and third directions.

[0059] Referring to Figure 6, an image sensor 300 according to one embodiment of the present invention includes a plurality of unit pixels PX, including at least one general pixel PX1, at least one autofocus pixel PX2, and at least one compensation pixel PXC, similar to the image sensor (100-1) shown in Figure 3a, and each pixel includes a corresponding microlens ML and grid GR.

[0060] As an example, each pixel group PG in the image sensor 300 includes two non-adjacent transparent color filters CF and two non-adjacent colored color filters CF. In the image sensor 300, the colored filter CF is one of the following: blue-green (C), magenta (M), or yellow (Y). For example, each pixel group PG includes a blue-green (C) or magenta (M) color filter and a yellow (Y) color filter. On the other hand, pixel group PG containing a magenta color filter (M) and pixel group PG containing a blue-green color filter (C) are arranged alternately in the second and third directions.

[0061] Referring to Figure 7, an image sensor 400 according to one embodiment of the present invention includes a plurality of unit pixels PX, including at least one general pixel PX1, at least one autofocus pixel PX2, and at least one compensation pixel PXC, similar to the image sensor (100-1) shown in Figure 3a, and each pixel includes a corresponding microlens ML and grid GR.

[0062] For example, each pixel group PG in the image sensor 400 includes two non-adjacent transparent color filters CF and two non-adjacent colored color filters CF. In the image sensor 400, each pixel group PG includes a red R color filter and a blue B color filter that are not adjacent to each other.

[0063] However, the arrangement of color filters included in the image sensors (200, 300, 400) shown in Figures 5 to 7 is merely an embodiment and not a limiting factor. For example, an image sensor may include color filters with a variety of patterns. However, an image sensor according to one embodiment of the present invention includes a general pixel PX1, an autofocus pixel PX2, and a compensation pixel PXC located on one side of the autofocus pixel PX2, wherein the compensation pixel PXC includes a small-sized compensation microlens MLC and a compensation grid GRC.

[0064] Figure 8 is a plan view illustrating the pixel array included in an image sensor according to one embodiment of the present invention. The image sensor (100-2) shown in Figure 3b includes a pixel array 100A containing a plurality of unit pixels PX arranged along a direction parallel to the upper surface of the substrate, and a logic circuit for acquiring pixel signals from the plurality of unit pixels PX. Figure 8 shows an example of the pixel array 100A of the image sensor (100-2) shown in Figure 3b.

[0065] Referring to Figure 8, in the pixel array 100A of an image sensor (100-2) according to one embodiment of the present invention, each of the multiple unit pixels PX is defined by an element isolation film. Multiple unit pixels (PX) form pixel groups (PG) in 2x2 arrays. Pixel group PG includes a color filter having a color filter array CFA that has a regular pattern for each "2x2" array. However, this is only one embodiment, and is not limited thereto. For example, an autofocus pixel PX2 includes a pair of parallel-arranged unit pixels PX, and each pair of unit pixels PX includes a colored filter of the same hue. As a result, the color filter array CFA may appear irregularly in some pixel groups PG.

[0066] On the other hand, each of the multiple unit pixels PX is one of the following: a general pixel PX1, an autofocus pixel PX2, and a compensation pixel PXC. Each of the multiple unit pixels PX includes a color filter separated from each other by a grid GR placed on an element isolation film, and a microlens ML placed on the color filter.

[0067] The compensation pixel PXC is located on one side of the autofocus pixel PX2, which contains a pair of unit pixels PX, and includes a transparent color filter. The compensation pixel PXC is configured to compensate for the signal output from the autofocus pixel PX2. For example, the signal output from the autofocus pixel PX2 is a signal for performing the autofocus function, and the compensation pixel PXC can improve the autofocus function of the image sensor (100-2) by compensating for the asymmetric output signal.

[0068] The above compensation can be achieved by the compensating microlens MLC included in the compensating pixel PXC, and the compensating microlens MLC is smaller than the general microlens ML1 included in the general pixel PX1. The sensitivity loss in the compensation pixel PXC caused by the difference in size of the microlens ML can be improved by using a smaller compensation grid GRC than the general grid GRN.

[0069] The image sensor (100-1) shown in Figure 3a indicates that one autofocus pixel PX2 corresponds to one pixel group PG, but this is only one embodiment and is not limited thereto. For example, at least one of the multiple pixel groups PG included in the image sensor (100-1) does not need to include an autofocus pixel PX2.

[0070] Furthermore, similar to the pixel array 100A of the image sensor (100-2) shown in Figure 8, one autofocus pixel PX2 can correspond to two pixel groups PG. In other words, the pair of unit pixels PX contained in the autofocus pixel PX2 are placed in two adjacent pixel groups PG.

[0071] Figures 9 and 11 are plan views illustrating an image sensor according to one embodiment of the present invention, Figure 10 is a cross-sectional view taken along the line II-II' in Figure 9, and Figure 12 is a cross-sectional view taken along the line III-III' in Figure 11. Referring to Figures 9 and 11, an image sensor (500, 600) according to one embodiment of the present invention includes a plurality of unit pixels PX, each including at least one general pixel PX1, at least one autofocus pixel PX2, and at least one compensation pixel PXC, similar to the image sensor (100-1) shown in Figure 3a, and each pixel includes a corresponding microlens ML and grid GR.

[0072] The autofocus pixels PX2 included in the image sensor (500, 600) include a pair of unit pixels PX arranged parallel to a second direction (e.g., the Y direction) perpendicular to a first direction (e.g., the Z direction). The pair of unit pixels PX contained in the autofocus pixel PX2 share the autofocus microlens ML2 and the colored filter CF. In the image sensors (500, 600) shown in Figures 9 and 10, the colored color filter CF is shown as a green G color filter; however, this is merely one embodiment and is not limited to this. Furthermore, the color filter array and the array of multiple unit pixels PX are not limited to those shown in the figure.

[0073] The compensation pixel PXC included in the image sensor (500, 600) is positioned on one side of the autofocus pixel PX2 and is formed to compensate for the signal output from the autofocus pixel PX2. The compensated pixel PXC includes a transparent W color filter and has a different structure from the general pixel PX1.

[0074] Referring to Figure 9, the compensation pixel PXC included in the image sensor 500 includes a compensation microlens MLC that is smaller than the general microlens ML1 included in the general pixel PX1. However, unlike the image sensor (100-1) shown in Figure 3a, the grid included in the compensation pixel PXC is the same as the general grid GRN included in the general pixel PX1.

[0075] Referring to Figure 11, the compensation pixel PXC included in the image sensor 600 includes a compensation grid GRC that is smaller than the general grid GRN included in the general pixel PX1. However, unlike the image sensor (100-1) shown in Figure 3a, the microlens ML included in the compensation pixel PXC is identical to the general microlens ML1 included in the general pixel PX1.

[0076] Referring to Figures 10 and 12, an image sensor (500, 600) according to one embodiment of the present invention includes a substrate (510, 610) having a first surface (511, 611) and a second surface (512, 612) facing each other, a photodiode PD disposed inside the substrate (510, 610) in each of a plurality of unit pixels PX, and an element isolation film DTI disposed between the plurality of unit pixels PX. Each unit pixel PX includes at least one general pixel PX1, at least one autofocus pixel PX2, and at least one compensation pixel PXC, all arranged along a direction parallel to the first plane (511, 611).

[0077] The compensation pixel PXC included in the image sensor 500 shown in Figure 10 includes a compensation microlens MLC that is smaller than the general microlens ML1 included in the general pixel PX1. On the other hand, the compensation pixel PXC included in the image sensor 600 shown in Figure 11 includes a compensation grid GRC that is smaller than the general grid GRN included in the general pixel PX1. For example, the compensation grid GRC has a shorter length than the general grid GRN in all directions, which allows the compensation pixel PXC of the image sensor 600 to have a wider aperture than the general pixel PX1.

[0078] Figure 13 is a plan view illustrating the pixel array included in an image sensor according to one embodiment of the present invention, and Figure 14 is a cross-sectional view illustrating the pixel array included in an image sensor according to one embodiment of the present invention, and is a cross-sectional view taken along the line IV-IV' in Figure 13. Referring to Figures 13 and 14, an image sensor 700 according to one embodiment of the present invention includes a pixel array in which a plurality of unit pixels PX are arranged. Figure 13 shows only a plurality of unit pixels PX arranged in an "8x8" configuration, but this is only one embodiment and is not limiting; the pixel array can contain many more unit pixels PX.

[0079] In an image sensor 700 according to one embodiment of the present invention, the microlenses ML and grid GR included in a plurality of unit pixels PX become smaller as they approach the edges of the pixel array. For example, a microlens MLa contained in a unit pixel PX located in the center of a pixel array has a first size, while a microlens MLb contained in a unit pixel PX located outside the center of the pixel array has a second size that is smaller than the first size. On the other hand, a microlens MLc contained within a unit pixel PX located at the edge of the pixel array can have a third size that is smaller than the second size.

[0080] Similarly, a grid GRc located on an element isolation film DTI that defines a unit pixel PX located at the edge of a pixel array is smaller than a grid GRb located on an element isolation film DTI that defines a unit pixel PX located further inside. Furthermore, the grid GRa located on the element isolation film DTI that defines the unit pixel PX located in the center of the pixel array is larger than the grid GRb located on the element isolation film DTI that defines the unit pixel PX located further out.

[0081] In an image sensor 700 according to one embodiment of the present invention, the size of the grid GR placed between pixels containing microlenses ML of different sizes corresponds to the size of the smaller microlens ML contained in two adjacent pixels. On the other hand, the image sensor 700, similar to the image sensor (100-1) shown in Figure 3a, includes a plurality of unit pixels PX, each containing at least one general pixel PX1, at least one autofocus pixel PX2, and at least one compensation pixel PXC, with each pixel including a corresponding microlens ML and grid GR.

[0082] Therefore, the image sensor 700 according to one embodiment of the present invention can improve lens shading occurring in the generated image by utilizing the structural differences between the microlens ML and the grid GR from the perspective of the entire pixel array. Furthermore, the compensation pixel PXC, which is positioned on one side of the autofocus pixel PX2 included in the image sensor 700 and includes a transparent W color filter, can prevent crosstalk in the autofocus pixel PX2 and improve the autofocus function of the image sensor 700.

[0083] Referring to Figure 14, in the pixel array of the image sensor 700, the central axis of each of the multiple unit pixels PX and the optical axis of the microlens ML contained within each of the multiple unit pixels PX do not overlap in the first direction (for example, the Z direction). For example, the distance between the central axis of a unit pixel PX and the optical axis of a microlens ML increases as you get closer to the edges of the pixel array. However, the pixel array of the image sensor 700 shown in Figures 13 and 14 is merely one embodiment and is not limited to those shown in the figures. For example, the arrangement of the color filters CF included in the image sensor 700 can be designed in various ways, and not only the size of the microlenses ML and the grid GR, but also the shape of the unit pixels PX can be varied in various ways as needed.

[0084] Figure 15 is a plan view illustrating the pixel array included in an image sensor according to one embodiment of the present invention, and Figure 16 is a cross-sectional view illustrating the pixel array included in an image sensor according to one embodiment of the present invention, and is a cross-sectional view taken along the line V-V' in Figure 15. Figures 15 and 16 correspond to the image sensor 700 shown in Figures 13 and 14, respectively.

[0085] Referring to Figures 15 and 16, an image sensor 800 according to one embodiment of the present invention includes a pixel array in which a plurality of unit pixels PX are arranged. However, similar to the image sensor 700 shown in Figures 13 and 14, the configuration and structure of the image sensor 800 are not limited to those shown in the figures.

[0086] The image sensor 800 includes a plurality of unit pixels PX, each containing at least one general pixel PX1, at least one autofocus pixel PX2, and at least one compensation pixel PXC, with each pixel including a corresponding microlens ML and grid GR. The autofocus pixel PX2 includes a pair of unit pixels PX arranged parallel to each other in one direction, and the compensation pixel PXC is located on one side of the autofocus pixel PX2 in the aforementioned one direction.

[0087] In an image sensor 800 according to one embodiment of the present invention, the microlenses ML and grids GR included in a plurality of unit pixels PX become smaller as they approach the edges of the pixel array. Furthermore, the compensated pixel PXC includes a compensated microlens MLC and a compensated grid GRC placed on a transparent W color filter, and each of the compensated microlens MLC and compensated grid GRC is smaller than the general microlens ML1 and general grid GRN included in the general pixel PX1.

[0088] For example, a microlens MLa contained in a unit pixel PX located in the center of a pixel array has a first size, while a microlens MLb contained in a unit pixel PX located outside the center of the pixel array has a second size that is smaller than the first size. On the other hand, the microlenses MLc contained within the unit pixels PX located at the edges of the pixel array have a third size that is smaller than the second size.

[0089] Furthermore, the microlens ML and grid GR included in the compensating pixel PXC are smaller than the microlens ML and grid GR included in the general pixel PX1 located around it. For example, a microlens MLd contained in a compensating pixel PXC located at the edge of a pixel array is smaller than a third-size microlens MLc. Similarly, a transparent color filter contained in a compensating pixel PXC located at the edge of the pixel array is separated from an adjacent color filter by a grid GRd that is smaller in size than the grid GRc contained in the adjacent general pixel PX1.

[0090] Similarly, a grid GRc located on an element isolation film DTI that defines a unit pixel PX located at the edge of a pixel array is smaller than a grid GRb located on an element isolation film DTI that defines a unit pixel PX located further inside. Furthermore, the grid GRa located on the element isolation film DTI that defines the unit pixel PX located in the center of the pixel array is larger than the grid GRb located on the element isolation film DTI that defines the unit pixel PX located further out.

[0091] An image sensor 800 according to one embodiment of the present invention, similar to the image sensor 700 shown in Figures 13 and 14, can improve lens shading occurring in the generated image by utilizing the structural differences between the microlenses ML and the grid GR from an overall perspective of the pixel array. Furthermore, the compensation pixel PXC, which is located on one side of the autofocus pixel PX2 included in the image sensor 800 and includes a transparent W color filter, can prevent crosstalk in the autofocus pixel PX2 and improve the autofocus function of the image sensor 800.

[0092] Figures 17a to 17f are cross-sectional views illustrating the image sensor formation process according to one embodiment of the present invention. Figures 17a to 17f are cross-sectional views (cut along the line I-I' in Figure 3a) showing the steps of forming the image sensor (100-1) according to one embodiment of the present invention described in Figure 3a. Referring to Figure 17a, the image sensor (100-1) is manufactured by forming an element isolation film DTI using a trench formed on the substrate 110.

[0093] As an example, a mask layer is laminated on one surface of the substrate 110 in order to form trenches only in the space where the element isolation film DTI should be formed. Trenches are not formed in the space where the mask layer exists, and the inside of trenches formed in the space where the mask layer does not exist is filled with insulating material, thereby forming the element isolation film DTI. The mask layer, along with the substrate 110 and a portion of the element isolation film DTI, is removed by a polishing process. For example, the upper surface of the substrate 110 that remains after being removed by the polishing process is defined as the second surface 112.

[0094] Referring to Figure 17b, in an image sensor (100-1) according to one embodiment of the present invention, a pixel circuit is arranged on the second surface 112 that remains after the polishing process. As described above, the pixel circuit includes multiple elements, a wiring pattern 170 connected to the multiple elements, and an insulating layer 180 covering the multiple elements and the wiring pattern 170. For example, the pixel circuit controls the operation of the image sensor (100-1). On the other hand, on the side opposite the second surface 112 of the substrate 110, a portion of the substrate 110 and the element isolation film DTI is removed by a polishing process. For example, the upper surface opposite to the substrate 110 that remains after being removed by the polishing process is defined as the first surface 111. This forms the internal structure and pixel circuit of the substrate 110 included in the image sensor (100-1).

[0095] Referring to Figure 17c, the element isolation film DTI included in the image sensor (100-1) penetrates the second surface 112 and the first surface 111 of the substrate 110. However, this is only one embodiment and is not limited thereto, and at least one of the element isolation films DTI may be formed to have different lengths from each other.

[0096] The process shown in Figures 17d to 17f is the process of forming the superstructure of the unit pixel PX included in the image sensor (100-1) described in Figure 4. As an example, a general grid GRN and a compensation grid GRC are formed on the element isolation film DTI on the second surface 112 of the substrate 110, a color filter CF is formed on the grid GR and the second surface 112, and a light transmission layer 130 is deposited on the upper surface thereof. Next, microlenses ML of various sizes for injecting light are deposited on the outermost part of the unit pixel PX, resulting in the image sensor (100-1) shown in Figure 3a. However, this is merely one embodiment and is not limited thereto; the manufacturing process may vary depending on the configuration and effects of the image sensor (100-1).

[0097] Figure 18 is a block diagram showing the schematic configuration of an electronic device including an image sensor according to one embodiment of the present invention, and Figure 19 is a block diagram showing the schematic configuration of the camera module 1100b in Figure 18. Referring to Figure 18, the electronic device 1000 includes a camera module group 1100, an application processor 1200, a PMIC 1300, and an external memory 1400.

[0098] The camera module group 1100 includes multiple camera modules (1100a, 1100b, 1100c). The figure shows an embodiment in which three camera modules (1100a, 1100b, and 1100c) are arranged, but the embodiment is not limited to this. In some embodiments, the camera module group 1100 may be modified to include only two camera modules. Furthermore, in some embodiments, the camera module group 1100 may be modified to include n camera modules (where n is a natural number greater than or equal to 4). In one embodiment, at least one of the multiple camera modules (1100a, 1100b, 1100c) included in the camera module group 1100 includes an image sensor according to one of the embodiments described above with reference to Figures 1 to 17f.

[0099] The detailed configuration of camera module 1100b will be described in more detail below with reference to Figure 19, but the following description can also be applied to other camera modules (1100a, 1100c) depending on the embodiment. Referring to Figure 19, the camera module 1100b includes a prism 1105, an optical path folding element (OPFE) 1110, an actuator 1130, an image sensing device 1140, and a storage device 1150.

[0100] The prism 1105 includes a reflective surface 1107 made of a light-reflecting material, which alters the path of light L incident from the outside. In some embodiments, the prism 1105 changes the path of light L incident in the X-axis direction to the Y-axis direction, which is perpendicular to the X-axis direction. Furthermore, the prism 1105 can rotate the reflective surface 1107 of the light-reflecting material in the A direction around the central axis 1106, or rotate the central axis 1106 in the B direction, thereby changing the path of light L incident in the X direction to the perpendicular Y direction. During this process, the OPFE1110 also moves in the Z-axis direction, which is perpendicular to the X-axis and Y-axis directions.

[0101] In one embodiment, as shown in the figure, the maximum rotation angle of the prism 1105 in the A direction is 15 degrees or less in the positive (+) A direction and greater than 15 degrees in the negative (-) A direction, but the embodiment is not limited thereto. In one embodiment, the prism 1105 can move within approximately 20 degrees in the positive (+) or negative (-)B direction, or between 10 and 20 degrees, or between 15 and 20 degrees, where the angle of movement can be the same angle in the positive (+) or negative (-)B direction, or within approximately 1 degree, up to a similar angle. In one embodiment, the prism 1105 can move the reflective surface 1107 of the light-reflecting material in the Z-axis direction parallel to the extension direction of the central axis 1106.

[0102] The OPFE1110 includes, for example, an optical lens consisting of m (where m is a natural number) groups. The m lenses move in a third direction, changing the optical zoom ratio of the camera module 1100b. For example, if the basic optical zoom magnification of the camera module 1100b is Z, then when moving the m optical lenses included in the OPFE 1110, the optical zoom magnification of the camera module 1100b can be changed to 3Z, 5Z, or an optical zoom magnification of 5Z or higher.

[0103] The actuator 1130 moves the OPFE 1110 or the optical lens (hereinafter referred to as the optical lens) to a specific position. For example, the actuator 1130 adjusts the position of the optical lens so that the sensor 1142 is positioned at the focal length of the optical lens for accurate sensing. For example, sensor 1142 is an image sensor.

[0104] The image sensing device 1140 includes a sensor 1142, control logic 1144, and memory 1146. The sensor 1142 senses an image of the object to be sensed using light L provided through an optical lens. The control logic 1144 controls the overall operation of the camera module 1100b. For example, the control logic 1144 controls the operation of the camera module 1100b in accordance with the control signals provided via the control signal line CSLb.

[0105] Memory 1146 stores information necessary for the operation of the camera module 1100b, such as calibration data 1147. Calibration data 1147 contains information necessary for the camera module 1100b to generate image data using light L supplied from an external source. The calibration data 1147 may include, for example, information regarding the degree of rotation, focal length, and optical axis. If the camera module 1100b is implemented as a multi-state camera where the focal length changes depending on the position of the optical lens, the calibration data 1147 includes the focal length value for each position (or state) of the optical lens and information regarding autofocusing.

[0106] The storage 1150 stores the image data sensed by the sensor 1142. The storage 1150 can be located outside the image sensing device 1140 and implemented in a stacked configuration with the sensor chips that make up the image sensing device 1140. In one embodiment, the storage 1150 can be implemented using EEPROM (Electrically Erasable Programmable Read-Only Memory), but the embodiments are not limited thereto.

[0107] Referring to both Figures 18 and 19, in one embodiment, each of the multiple camera modules (1100a, 1100b, 1100c) includes an actuator 1130. As a result, each of the multiple camera modules (1100a, 1100b, 1100c) contains the same or different calibration data 1147 resulting from the operation of the actuator 1130 contained within it.

[0108] In one embodiment, one of the multiple camera modules (1100a, 1100b, 1100c) (e.g., 1100b) is a folded lens camera module including the prism 1105 and OPFE 1110 described above, while the remaining camera modules (e.g., 1100a, 1100c) are vertical camera modules that do not include the prism 1105 and OPFE 1110; however, the embodiments are not limited thereto.

[0109] In one embodiment, one of the multiple camera modules (1100a, 1100b, 1100c) (for example, 1100c) is a vertical depth camera that extracts depth information using, for example, IR (Infrared Ray). In this case, the application processor 1200 can merge the image data provided by the depth camera with the image data provided by other camera modules (e.g., 1100a or 1100b) to generate a 3D depth image.

[0110] In one embodiment, at least two of the multiple camera modules (1100a, 1100b, 1100c) (for example, 1100a and 1100b) have different fields of view (angles of view). In this case, for example, the optical lenses of at least two camera modules (e.g., 1100a and 1100b) among the multiple camera modules (1100a, 1100b, and 1100c) are different from each other, but are not limited to this.

[0111] Furthermore, in one embodiment, the field of view of each of the multiple camera modules (1100a, 1100b, 1100c) is different from that of the others. In this case, the optical lenses included in each of the multiple camera modules (1100a, 1100b, 1100c) are different from each other, but are not limited to this.

[0112] In one embodiment, each of the multiple camera modules (1100a, 1100b, 1100c) is arranged physically separated from one another. In other words, instead of multiple camera modules (1100a, 1100b, 1100c) dividing and using the sensing area of ​​a single sensor 1142, an independent sensor 1142 is placed inside each of the multiple camera modules (1100a, 1100b, 1100c).

[0113] Referring further to Figure 18, the application processor 1200 includes an image processing unit 1210, a memory controller 1220, and an internal memory 1230. The application processor 1200 can also be implemented separately from the multiple camera modules (1100a, 1100b, 1100c). For example, the application processor 1200 and multiple camera modules (1100a, 1100b, 1100c) can be implemented on separate semiconductor chips, isolated from each other.

[0114] The image processing unit 1210 includes a plurality of subprocessors (1212a, 1212b, 1212c), an image generator 1214, and a camera module controller 1216. The image processing device 1210 includes multiple subprocessors (1212a, 1212b, 1212c) in a number corresponding to the number of camera modules (1100a, 1100b, 1100c).

[0115] Image data generated from each camera module (1100a, 1100b, 1100c) is provided to the corresponding subprocessors (1212a, 1212b, 1212c) via separate image signal lines (ISLa, ISLb, ISLc). For example, image data generated from camera module 1100a is provided to subprocessor 1212a via image signal line ISLa, image data generated from camera module 1100b is provided to subprocessor 1212b via image signal line ISLb, and image data generated from camera module 1100c is provided to subprocessor 1212c via image signal line ISLc. Such image data can be transmitted, for example, using a Camera Serial Interface (CSI) based on MIPI (Mobile Industry Processor Interface), but the embodiments are not limited thereto.

[0116] On the other hand, in one embodiment, one subprocessor may be arranged to support multiple camera modules. For example, instead of subprocessors 1212a and 1212c being implemented separately as shown in the figure, they can be implemented integrated as a single subprocessor, and the image data provided from camera modules 1100a and 1100c can be selected by a selection element (e.g., a multiplexer) and then provided to the integrated subprocessor.

[0117] The image data provided to each subprocessor (1212a, 1212b, 1212c) is then provided to the image generator 1214. The image generator 1214 generates an output image using image data provided by each subprocessor (1212a, 1212b, 1212c) according to the generating information or mode signal. Specifically, the image generator 1214 merges at least a portion of the image data generated from camera modules (1100a, 1100b, 1100c) having different field-of-view angles, according to the image generation information or mode signal, to generate an output image. Furthermore, the image generator 1214 selects one of the image data generated from camera modules (1100a, 1100b, 1100c) having different field-of-view angles, according to the image generation information or mode signal, and generates an output image.

[0118] In one embodiment, the image generation information may include a zoom signal (or zoom factor). In one embodiment, the mode signal may be, for example, a signal based on a mode selected by the user. If the image generation information is a zoom signal (zoom factor), and each camera module (1100a, 1100b, 1100c) has a different field of view (field of view angle), the image generator 1214 will perform different operations depending on the type of zoom signal.

[0119] For example, if the zoom signal is the first signal, the image data output from camera module 1100a and the image data output from camera module 1100c are merged, and then the merged image signal and the image data output from camera module 1100b, which was not used in the merging, are used to generate the output image. If the zoom signal is a second signal different from the first signal, the image generator 1214 does not merge such image data, but instead selects one of the image data output from each camera module (1100a, 1100b, 1100c) to generate the output image. However, the embodiments are not limited thereto, and the method for processing image data can be modified and implemented in any way as needed.

[0120] In one embodiment, the image generator 1214 receives multiple image data with different exposure times from at least one of the multiple subprocessors (1212a, 1212b, 1212c), and performs HDR (high dynamic range) processing on the multiple image data to generate merged image data with an increased dynamic range.

[0121] The camera module controller 1216 provides control signals to each camera module (1100a, 1100b, 1100c). Control signals generated by the camera module controller 1216 are provided to the corresponding camera modules (1100a, 1100b, 1100c) via separate control signal lines (CSLa, CSLb, CSLc).

[0122] One of the multiple camera modules (1100a, 1100b, 1100c) is designated as the master camera (e.g., 1100b) depending on the image generation information or mode signal, including the zoom signal, while the remaining camera modules (e.g., 1100a, 1100c) are designated as slave cameras. This information is included in the control signals and provided to the corresponding camera modules (1100a, 1100b, 1100c) via separate control signal lines (CSLa, CSLb, CSLc).

[0123] Depending on the zoom factor or operating mode signal, the camera module operating as the master camera and the camera operating as the slave camera can be changed. For example, if the field of view of camera module 1100a is wider than that of camera module 1100b, and exhibits a lower zoom factor, then camera module 1100b operates as the master camera and camera module 1100a operates as the slave camera. Conversely, when the zoom factor indicates a high zoom ratio, camera module 1100a operates as the master camera and camera module 1100b operates as the slave camera.

[0124] In one embodiment, the control signals provided from the camera module controller 1216 to each camera module (1100a, 1100b, 1100c) may include a sync enable signal. For example, if camera module 1100b is the master camera and camera modules (1100a, 1100c) are slave cameras, the camera module controller 1216 transmits a sink enable signal to camera module 1100b. When such a sync enable signal is provided to camera module 1100b, it generates a sync signal based on the provided sync enable signal and provides the generated sync signal to camera modules (1100a, 1100c) via the sync signal line SSL. Camera module 1100b and camera modules (1100a, 1100c) are synchronized to such a sink signal and transmit image data to the application processor 1200.

[0125] In one embodiment, the control signals provided from the camera module controller 1216 to a plurality of camera modules (1100a, 1100b, 1100c) include mode information corresponding to the mode signal. Based on this mode information, the multiple camera modules (1100a, 1100b, 1100c) operate in a first operating mode and a second operating mode in relation to the sensing speed. Multiple camera modules (1100a, 1100b, 1100c) generate an image signal at a first speed in a first operating mode (for example, an image signal at a first frame rate), encode it at a second speed higher than the first speed (for example, an image signal at a second frame rate higher than the first frame rate), and transmit the encoded image signal to the application processor 1200. In this case, the second velocity is no more than 30 times the first velocity.

[0126] The application processor 1200 stores the received image signal, in other words, the encoded image signal, in its internal memory 1230 or external memory 1400. It then reads the encoded image signal from the internal memory 1230 or external memory 1400, decodes it, and displays the image data generated based on the decoded image signal. For example, one of the multiple subprocessors (1212a, 1212b, 1212c) of the image processing device 1210 performs decoding, and also performs image processing on the decoded image signal.

[0127] Multiple camera modules (1100a, 1100b, 1100c) generate image signals in a second operating mode at a third speed lower than the first speed (for example, generating image signals at a third frame rate lower than the first frame rate) and transmit the image signals to the application processor 1200. The image signal provided to the application processor 1200 may be an unencoded signal. The application processor 1200 either performs image processing on the received image signal or stores the image signal in the internal memory 1230 or the external memory 1400.

[0128] The PMIC1300 supplies power, such as power supply voltage, to each of the multiple camera modules (1100a, 1100b, 1100c). For example, under the control of the application processor 1200, the PMIC 1300 supplies first power to camera module 1100a via power signal line PSLa, second power to camera module 1100b via power signal line PSLb, and third power to camera module 1100c via power signal line PSLc.

[0129] The PMIC1300 responds to the power control signal PCON from the application processor 1200 to generate and adjust the power levels for each of the multiple camera modules (1100a, 1100b, 1100c). The power control signal PCON includes power adjustment signals for each operating mode of multiple camera modules (1100a, 1100b, 1100c). For example, the operating mode includes a low power mode, in which case the power control signal PCON includes information about the camera module operating in low power mode and the power level to be set. The power levels supplied to each of the multiple camera modules (1100a, 1100b, 1100c) are either identical or different from one another. Furthermore, the power level can be changed dynamically.

[0130] Furthermore, the present invention is not limited to the embodiments described above. It can be modified and implemented in various ways without departing from the technical scope of the present invention. [Explanation of Symbols]

[0131] Image sensors: 1, 100, 100-1, 100-2, 200, 300, 400, 500, 600, 700, 800 10, 100A Pixel Array 20 Logic Circuits 21 Low Driver 22. Lead-out circuit 23 Column Drivers 24 Control Logic 110 circuit boards 111, 112 1st page, 2nd page 130 Light transmission layer 170 wiring patterns 180 Insulating layer CF Color Filter CFA Color Filter Array DTI element separation membrane GR Grid GRC Compensation Grid GRN General Grid ML Microlens ML1 General Microlens ML2 Autofocus Microlens MLC Compensation Microlenses PD photodiode PG Pixel Group PX (pixels) PX1 General Pixel PX2 Autofocus Pixels PXC Compensated Pixels

Claims

1. A substrate comprising a first surface and a second surface facing each other in a first direction, wherein a plurality of unit pixels are arranged along a direction parallel to the first surface, including at least one general pixel, at least one autofocus pixel, and at least one compensation pixel. In each of the plurality of unit pixels, a photodiode is disposed inside the substrate, The system comprises an element isolation film disposed between the plurality of unit pixels, The autofocus pixels include a pair of unit pixels arranged parallel to a second direction perpendicular to the first direction, Each of the plurality of unit pixels includes a color filter arranged on the first surface and separated from each other by a grid, and a microlens arranged on the color filter. The aforementioned general pixel includes a general microlens, The compensation pixel is positioned adjacent only to one side of the autofocus pixel in the second direction in which the pair of unit pixels are arranged in parallel, and includes a transparent color filter and a compensation microlens smaller than the general microlens, and is characterized in that the compensation microlens, which is smaller than the general microlens included in the general pixel, compensates for the asymmetric output generated by the pair of unit pixels included in the autofocus pixel.

2. The image sensor according to claim 1, characterized in that the pair of unit pixels share an autofocus microlens.

3. The image sensor according to claim 2, characterized in that a pair of unit pixels included in the autofocus pixels include a colored color filter of the same hue.

4. The image sensor according to claim 2, characterized in that the compensation pixel is arranged on one side of the autofocus pixel in the second direction.

5. The image sensor according to claim 4, characterized in that the pixel located adjacent to the other side of the autofocus pixel on the opposite side of the autofocus pixel in the second direction is a general pixel including a colored color filter.

6. The image sensor according to claim 1, characterized in that the grid includes a metal or transparent material.

7. The aforementioned general pixel includes a general grid, The image sensor according to claim 1, characterized in that the transparent color filter included in the compensation pixel is separated from adjacent color filters by a compensation grid smaller than the general grid.

8. The image sensor according to claim 7, characterized in that, in a second direction perpendicular to the first direction, the length of the color filter included in the general pixel is smaller than the length of the color filter included in the compensation pixel.

9. circuit board and A pixel array including a plurality of pixel groups arranged along a direction parallel to the upper surface of the substrate, The system includes a logic circuit that acquires pixel signals from the aforementioned pixel array, Each of the plurality of pixel groups includes a plurality of unit pixels, each defined by an element isolation film extending in a first direction perpendicular to the upper surface of the substrate, and including at least one autofocus pixel, at least one compensation pixel, and at least one general pixel. Each of the plurality of unit pixels includes a photodiode disposed inside the substrate, a color filter disposed on the upper surface of the substrate and separated from adjacent color filters by a grid, and a microlens disposed on the color filter. The compensation pixel compensates for the signal output from the autofocus pixel and includes a compensation microlens smaller than the microlens included in the adjacent pixel, and a transparent color filter. The pair of unit pixels included in the autofocus pixel are arranged parallel to a second direction perpendicular to the first direction, The image sensor is characterized in that the compensation pixel is arranged adjacent only to one side of the autofocus pixel in the second direction in which the pair of unit pixels are arranged in parallel.

10. The image sensor according to claim 9, characterized in that the unit pixels included in the autofocus pixels are arranged parallel to a second direction perpendicular to the first direction and include a colored color filter of the same hue.

11. Each of the aforementioned plurality of pixel groups includes a unit pixel arranged in a "2x2" configuration. The plurality of pixel groups include a first pixel group consisting only of the general pixels and the compensation pixels, The image sensor according to claim 9, characterized in that the first pixel group includes two transparent color filters that are not adjacent to each other and two colored color filters that are not adjacent to each other.

12. The image sensor according to claim 9, characterized in that the microlenses and the grid become smaller as they approach the edges of the pixel array.

13. The image sensor according to claim 12, characterized in that the distance between the central axis of each of the plurality of unit pixels and the optical axis of the microlens contained in each of the plurality of unit pixels increases as it approaches the edge of the pixel array.

14. The image sensor according to claim 9, characterized in that the compensation pixel includes a compensation grid smaller than the grid included in the pixel adjacent to the compensation pixel.

15. The image sensor according to claim 9, characterized in that, in a second direction perpendicular to the first direction and a third direction perpendicular to the second direction, the length of the grid corresponds to the size of the smallest microlens among the microlenses corresponding to each of the color filters separated by the grid.

16. The image sensor according to claim 9, characterized in that the pair of unit pixels included in the autofocus pixels are arranged in each of two adjacent pixel groups.

17. A substrate including a first surface and a second surface facing each other in the first direction, Multiple unit pixels arranged on the substrate, In each of the aforementioned unit pixels, a photodiode is disposed inside the substrate, The system comprises an element isolation film disposed between the unit pixels, Each of the aforementioned unit pixels forms an autofocus pixel, a general pixel, and a compensation pixel. The system includes a color filter arranged on the first surface and separated from adjacent color filters by a grid, and a microlens arranged on the color filter, The autofocus pixels include a pair of the unit pixels arranged parallel to a second direction perpendicular to the first direction, The pair of unit pixels share the microlens and the color filter, The image sensor is characterized in that the compensation pixel has a structure different from the general pixel, is positioned adjacent only to one side of the autofocus pixel in the second direction in which the pair of unit pixels are arranged in parallel, includes a transparent color filter, and compensates for the signal output from the autofocus pixel.

18. The image sensor according to claim 17, characterized in that the compensation pixel includes a compensation microlens smaller than the general microlens included in the general pixel.

19. The image sensor according to claim 17, characterized in that the compensation pixel includes a compensation grid having a shorter length than the general grid included in the general pixel in the second direction and a third direction perpendicular to the second direction.

Images