Image sensor and image processing method, and electronic device including the image sensor

Abstract

To provide an image sensor and an image processing method of the same.SOLUTION: An image sensor includes a spectral filter containing a plurality of unit filters arranged in a two-dimensional array and having different center wavelengths, a pixel array that receives light transmitted through the spectral filter and outputs an image signal, and a processor that performs image processing on the image signal output from the pixel array.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to an image sensor and an image processing method, as well as to an electronic device including an image sensor. [Background technology]

[0002] Image sensors using spectral filters are one of the most important optical devices in the field of optics. Conventional image sensors contain a variety of optical elements, making them large in volume and heavy. In recent years, in response to the demand for miniaturization of image sensors, research is being conducted into simultaneously implementing integrated circuits and optical elements on a single semiconductor chip. Summary of the Invention [Problem to be solved by the invention]

[0003] The problem to be solved by the present invention is to provide an image sensor and an image processing method for the image sensor. [Means for solving the problem]

[0004] In one aspect, a spectral filter including a plurality of unit filters arranged two-dimensionally and having different center wavelengths; a pixel array that receives light transmitted through the spectral filter and outputs a video signal; a processor that performs image processing on the image signal output from the pixel array; the plurality of unit filters include at least one first unit filter having a center wavelength in a first wavelength range and at least one second unit filter having a center wavelength in a second wavelength range; The first unit filter is provided as an image sensor including a plurality of first metal reflective layers spaced apart from each other and including a first metal, and at least one first cavity disposed between the plurality of first metal reflective layers.

[0005] The pixel array may be provided corresponding to the plurality of unit filters.

[0006] The processor may independently perform image processing on each of the image signals output from the pixel array and output the processed image signals.

[0007] The processor may combine two or more image signals among the image signals output from the pixel array, perform image processing on the combined image signals, and output the combined image signals. For example, the processor may combine two or four image signals among the image signals output from the pixel array, perform image processing on the combined image signals, and output the combined image signals.

[0008] The two or more video signals may be output from pixels adjacent to each other, and the plurality of unit filters may be arranged so that their center wavelengths are adjacent to each other.

[0009] The spectral filter may further include red, green, and blue color filters disposed on the same plane as the plurality of unit filters, and the pixel array may be provided corresponding to the plurality of unit filters and the red, green, and blue color filters.

[0010] The processor may further perform image processing on the image signals output from the pixels corresponding to the red, green, and blue color filters.

[0011] The spectral filter may further include a blank filter that is provided on the same plane as the plurality of unit filters and that transmits incident light as is. The pixel array may be provided corresponding to the plurality of unit filters and the blank filter.

[0012] The processor may further perform image processing on the video signal output from the pixel corresponding to the blank filter.

[0013] The at least one first unit filter may form a first filter array including a plurality of first unit filters having different center wavelengths, and the at least one second unit filter may form a second filter array including a plurality of second unit filters having different center wavelengths.

[0014] The second unit filter may include a plurality of second metal reflective layers spaced apart from each other and including a second metal different from the first metal, and at least one second cavity disposed between the plurality of second metal reflective layers.

[0015] The center wavelength of the first unit filter is adjusted by changing the thickness or effective refractive index of the first cavity, and the center wavelength of the second unit filter is adjusted by changing the thickness or effective refractive index of the second cavity.

[0016] The first unit filter may further include first and second dielectric layers provided at the bottom and top of the first cavity, and the second unit filter may further include third and fourth dielectric layers provided at the bottom and top of the second cavity.

[0017] The thickness or effective refractive index of each of the first and second dielectric layers is also adjusted according to the center wavelength of the first unit filter, and the thickness or effective refractive index of each of the third and fourth dielectric layers is also adjusted according to the center wavelength of the second unit filter.

[0018] The second unit filter may include a plurality of Bragg reflecting layers spaced apart from one another, and at least one second cavity disposed between the plurality of Bragg reflecting layers.

[0019] In another aspect, In the above image sensor, an image processing method is provided in which the processor performs image processing on the video signal output from the pixel array.

[0020] The pixel array may be provided corresponding to the plurality of unit filters.

[0021] The processor may independently perform image processing on each of the image signals output from the pixel array and output the processed image signals.

[0022] The processor may combine two or more image signals among the image signals output from the pixel array, perform image processing on the combined image signals, and output the combined image signals. For example, the processor may combine two or four image signals among the image signals output from the pixel array, perform image processing on the combined image signals, and output the combined image signals.

[0023] The two or more video signals may be output from pixels adjacent to each other, and the plurality of unit filters may be arranged so that their center wavelengths are adjacent to each other.

[0024] The spectral filter may further include red, green, and blue color filters arranged on the same plane as the plurality of unit filters, and the pixel array may be arranged corresponding to the plurality of unit filters and the red, green, and blue color filters.

[0025] The processor may further perform image processing on the image signals output from the pixels corresponding to the red, green, and blue color filters.

[0026] The spectral filter may further include a blank filter that is provided on the same plane as the plurality of unit filters and that transmits incident light as is, and the pixel array may be provided corresponding to the plurality of unit filters and the blank filter.

[0027] The processor may further perform image processing on the video signal output from the pixel corresponding to the blank filter.

[0028] The second unit filter may include a plurality of second metal reflective layers spaced apart from each other and including a second metal different from the first metal, and at least one second cavity disposed between the plurality of second metal reflective layers.

[0029] The second unit filter may include a plurality of Bragg reflecting layers spaced apart from one another, and at least one second cavity disposed between the plurality of Bragg reflecting layers.

[0030] In yet another aspect, a spectral filter including a plurality of unit filters having different center wavelengths; a pixel array that receives light transmitted through the spectral filter and outputs a video signal; a processor that performs image processing on the image signal output from the pixel array; The processor may include an image sensor that combines two or more image signals output from the pixel array into one image signal, performs image processing on the combined image signal, and outputs the combined image signal.

[0031] The pixel array may include a plurality of blue pixels, a plurality of green pixels, and a plurality of red pixels, in which case the processor may combine at least one of the video signals output from the blue pixels and perform image processing, combine at least one of the video signals output from the green pixels and perform image processing, and combine at least one of the video signals output from the red pixels and perform image processing.

[0032] The pixel array may further include a plurality of ultraviolet (UV) pixels, in which case the processor may combine at least one of the UV image signals output from the UV pixels to perform image processing.

[0033] The pixel array may further include a plurality of near-infrared (NIR) pixels, in which case the processor may combine at least one of the video signals output from the NIR pixels and perform image processing.

[0034] The processor can further process and output spectral information for each video signal output from the pixel array.

[0035] The processor may apply a weighting value according to a specific wavelength region to at least one of the image signals output from the pixel array, and then perform image processing using a sum or difference of the image signals.

[0036] The plurality of unit filters may include at least one first unit filter having a center wavelength in a first wavelength range, and at least one second unit filter having a center wavelength in a second wavelength range.

[0037] The first unit filter may include a plurality of first metal reflective layers spaced apart from each other and including a first metal, and at least one first cavity provided between the plurality of first metal reflective layers.

[0038] The second unit filter may include a plurality of second metal reflective layers spaced apart from each other and including a second metal different from the first metal, and at least one second cavity disposed between the plurality of second metal reflective layers.

[0039] The second unit filter may include a plurality of Bragg reflecting layers spaced apart from one another, and at least one second cavity disposed between the plurality of Bragg reflecting layers.

[0040] The image sensor may further include a timing controller, a row decoder, and an output circuit. [Brief explanation of the drawings]

[0041] [Figure 1] FIG. 1 is a block diagram of an image sensor according to an exemplary embodiment. [Figure 2] 2 is a diagram schematically illustrating a cross section of the spectral filter taken along line II-II' in FIG. [Figure 3A] 1 is a diagram showing a unit filter in which a TiO 2 cavity is provided between Cu reflective layers. [Figure 3B] 3B is a diagram showing a unit filter in which TiO2 dielectric layers are provided on the upper and lower parts of the structure shown in FIG. 3A. [Figure 4] 3C is a diagram showing transmission spectra of the unit filter shown in FIG. 3A and the unit filter shown in FIG. 3B. [Figure 5] FIG. 10 is a cross-sectional view schematically illustrating a spectral filter according to another exemplary embodiment. [Figure 6] 6 is a diagram showing the transmission spectrum of the spectral filter shown in FIG. 5. [Figure 7] FIG. 10 is a cross-sectional view schematically illustrating a spectral filter according to yet another exemplary embodiment. [Figure 8] 8 is a diagram showing a transmission spectrum of the spectral filter shown in FIG. 7. [Figure 9] FIG. 10 is a cross-sectional view schematically illustrating a spectral filter according to yet another exemplary embodiment. [Figure 10] FIG. 10 is a cross-sectional view schematically illustrating a spectral filter according to yet another exemplary embodiment. [Figure 11] FIG. 10 is a cross-sectional view schematically illustrating a spectral filter according to yet another exemplary embodiment. [Figure 12] FIG. 10 is a cross-sectional view schematically illustrating a spectral filter according to yet another exemplary embodiment. [Figure 13] FIG. 10 is a cross-sectional view schematically illustrating a spectral filter according to yet another exemplary embodiment. [Figure 14] FIG. 10 is a cross-sectional view schematically illustrating a spectral filter according to yet another exemplary embodiment. [Figure 15]FIG. 10 is a cross-sectional view schematically illustrating a spectral filter according to yet another exemplary embodiment. [Figure 16] 16 is a diagram showing the transmission spectrum of the spectral filter shown in FIG. 15. [Figure 17] FIG. 10 is a cross-sectional view schematically illustrating a spectral filter according to yet another exemplary embodiment. [Figure 18] 2 is an exemplary plan view of a spectral filter applicable to the image sensor of FIG. 1. FIG. [Figure 19] 1. FIG. 4 is a plan view showing another example of a spectral filter applicable to the image sensor of FIG. [Figure 20] 1. FIG. 4 is a plan view showing yet another exemplary spectral filter applicable to the image sensor of FIG. [Figure 21] FIG. 2 is a plan view illustrating an exemplary pixel array of an image sensor according to an exemplary embodiment. [Figure 22] 22 is a diagram showing a transmission spectrum obtained by an image processing method according to an exemplary embodiment in the pixel array shown in FIG. 21 . [Figure 23] 10 is a diagram illustrating an image processing method according to another exemplary embodiment; [Figure 24] 10 is a diagram illustrating an image processing method according to yet another exemplary embodiment; [Figure 25] FIG. 10 is a cross-sectional view schematically illustrating a spectral filter according to yet another exemplary embodiment. [Figure 26] 26 is a plan view exemplarily showing a pixel array of an image sensor provided corresponding to the spectral filter of FIG. 25. FIG. [Figure 27] 27 is a diagram showing an example of a transmission spectrum obtained by an image processing method according to an exemplary embodiment in the pixel array shown in FIG. 26. [Figure 28] FIG. 10 is a cross-sectional view schematically illustrating a spectral filter according to yet another exemplary embodiment. [Figure 29] 29 is a plan view exemplarily showing a pixel array of an image sensor provided corresponding to the spectral filter of FIG. 28. FIG. [Figure 30] 30 is a diagram showing an example of a transmission spectrum obtained by an image processing method according to an exemplary embodiment in the pixel array shown in FIG. 29. [Figure 31] FIG. 10 is a cross-sectional view schematically illustrating a spectral filter according to yet another exemplary embodiment. [Figure 32] 32 is a diagram showing an example of a wideband filter that can be used as the additional filter shown in FIG. 31. [Figure 33] 32 is a diagram showing another example of a wideband filter that can be used as the additional filter shown in FIG. 31. [Figure 34] FIG. 10 is a cross-sectional view schematically illustrating a spectral filter according to yet another exemplary embodiment. [Figure 35] FIG. 1 is a block diagram that schematically illustrates an electronic device including an image sensor according to an exemplary embodiment. [Figure 36] FIG. 36 is a block diagram illustrating the camera module of FIG. 35. [Figure 37] 1A to 1C are diagrams illustrating various examples of electronic devices to which image sensors according to exemplary embodiments are applied; [Figure 38] 1A to 1C are diagrams illustrating various examples of electronic devices to which image sensors according to exemplary embodiments are applied; [Figure 39] 1A to 1C are diagrams illustrating various examples of electronic devices to which image sensors according to exemplary embodiments are applied; [Figure 40] 1A to 1C are diagrams illustrating various examples of electronic devices to which image sensors according to exemplary embodiments are applied; [Figure 41] 1A to 1C are diagrams illustrating various examples of electronic devices to which image sensors according to exemplary embodiments are applied; [Figure 42] 1A to 1C are diagrams illustrating various examples of electronic devices to which image sensors according to exemplary embodiments are applied; [Figure 43] 1A to 1C are diagrams illustrating various examples of electronic devices to which image sensors according to exemplary embodiments are applied; [Figure 44] 1A to 1C are diagrams illustrating various examples of electronic devices to which image sensors according to exemplary embodiments are applied; [Figure 45] 1A to 1C are diagrams illustrating various examples of electronic devices to which image sensors according to exemplary embodiments are applied; [Figure 46] 1A to 1C are diagrams illustrating various examples of electronic devices to which image sensors according to exemplary embodiments are applied; DETAILED DESCRIPTION OF THE INVENTION

[0042] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the following drawings, the same reference numerals refer to the same components, and the size of each component may be exaggerated in the drawings for clarity and convenience of explanation. Meanwhile, the embodiments described below are merely examples, and various modifications are possible from these embodiments.

[0043] Hereinafter, the terms "upper" and "above" include not only those immediately above, below, left, and right in contact, but also those not in contact but above, below, left, and right. Unless otherwise specified in the context, singular expressions include plural expressions. Furthermore, when a part "comprises" a certain element, this does not mean excluding other elements, but means that it further includes other elements, unless otherwise specified.

[0044] Use of the term "said" and similar directives refers to both the singular and the plural. Unless an order of steps in a method is expressly stated or otherwise specified, the steps may be performed in any order and are not necessarily limited to the order stated.

[0045] Furthermore, terms such as "unit" and "module" used in the specification refer to a unit that processes at least one function or operation, and may be implemented by hardware or software, or by a combination of hardware and software.

[0046] The line connections or connecting members between components shown in the drawings are illustrative of functional connections and / or physical or circuit connections, and in an actual device, various alternative or additional functional connections, physical connections, or circuit connections may be implemented.

[0047] The use of any examples or exemplary terms is intended merely to illustrate the technical idea, and the scope of the invention is not limited by such examples or exemplary terms unless limited by the claims.

[0048] FIG. 1 is a schematic block diagram of an image sensor according to an exemplary embodiment.

[0049] 1, the image sensor 1000 includes a spectral filter 1100, a pixel array 4100, a timing controller 4010, a row decoder 4020, an output circuit 4030, and a processor 4200. The image sensor may include, but is not limited to, a charge coupled device (CCD) image sensor or a complementary metal oxide semiconductor (CMOS) image sensor.

[0050] The spectral filter 1100 transmits light of different wavelength ranges and includes a plurality of unit filters arranged two-dimensionally. The pixel array 4100 includes a plurality of pixels that sense light of different wavelengths transmitted through the plurality of unit filters. Specifically, the pixel array 4100 includes pixels arranged two-dimensionally along a plurality of rows and a plurality of columns. The row decoder 4020 selects one of the rows of the pixel array 4100 in response to a row address signal output from the timing controller 4010. The output circuit 4030 outputs a photodetection signal in units of columns from the plurality of pixels arranged along the selected row. To this end, the output circuit 4030 includes a column decoder and an analog-to-digital converter (ADC). For example, the output circuit 4030 may include a plurality of ADCs arranged for each column between the column decoder and the pixel array 4100, or a single ADC arranged at the output end of the column decoder. The timing controller 4010, the row decoder 4020, and the output circuit 4030 may be implemented as a single chip or separate chips. The image signal output via the output circuit 4030 may be processed by the processor 4200. The method by which the processor 4200 performs image processing will be described later. The processor 4200 may be implemented as a single chip together with the timing controller 4010, the row decoder 4020, and the output circuit 4030. The pixel array 4100 includes a plurality of pixels that sense light of different wavelengths, and the pixel arrangement may be implemented in various ways.

[0051] The following describes in detail the spectral filter 1100 of the image sensor 1000. Figure 2 is a cross-sectional view of the spectral filter taken along line II-II' in Figure 1.

[0052] 1 and 2, the spectral filter 1100 includes a plurality of unit filters arranged two-dimensionally. In Fig. 2, cross sections of six unit filters 111, 112, 113, 121, 122, and 123 are shown as an example.

[0053] The spectral filter 1100 may include first and second filter arrays 110 and 120 arranged on a plane. The first and second filter arrays 110 and 120 may be arranged on substantially the same plane, but are not necessarily arranged on the same plane. The first filter array 110 includes at least one unit filter having a center wavelength in a first wavelength range. Here, the first wavelength range may include, for example, a range of approximately 250 nm to 600 nm. However, this is merely an example, and the first wavelength range may include various wavelength ranges depending on design conditions. FIG. 2 illustrates an example in which the first filter array 110 includes first, second, and third unit filters 111, 112, and 113.

[0054] The second filter array 120 includes at least one unit filter having a center wavelength in a second wavelength range. The second wavelength range is a longer wavelength range than the first wavelength range. For example, the second wavelength range may include a range from approximately 600 nm to 1100 nm. However, this is merely an example, and the second wavelength range may include various other wavelength ranges depending on design conditions. FIG. 2 illustrates an example in which the second filter array 120 includes fourth, fifth, and sixth unit filters 121, 122, and 123.

[0055] FIG. 2 shows a case where the first filter array 110 includes three unit filters 111, 112, and 113, and the second filter array 120 includes three unit filters 121, 122, and 123, but this is merely an example, and the number of unit filters constituting each of the first and second filter arrays 110 and 120 can be varied in various ways.

[0056] Each of the first, second, and third unit filters 111, 112, and 113 constituting the first filter array 110 transmits a specific center wavelength within a first wavelength region, and may have a Fabry-Perot structure in which cavities 141, 142, and 143 are provided between two first metal reflective layers 131 and 132 spaced apart from each other.

[0057] When light passes through the first metal reflective layers 131 and 132 and enters the cavities 141, 142, and 143, the light travels back and forth between the first metal reflective layers 131 and 132 and inside the cavities 141, 142, and 143, causing constructive interference and destructive interference in the process. Then, light having a specific center wavelength that satisfies the constructive interference condition is emitted to the outside of the unit filters 111, 112, and 113. Here, the wavelength band and center wavelength of the light passing through the unit filters 111, 112, and 113 are also determined by the reflection band of the first metal reflective layers 131 and 132 and the characteristics of the cavities 141, 142, and 143.

[0058] The first metal reflective layers 131, 132 may include a first metal capable of reflecting light in a first wavelength region. For example, the first metal may include, but is not limited to, Al, Ag, Au, or TiN. The first metal reflective layers 131, 132 may be formed to a thickness of several tens of nanometers, but this is merely exemplary. As a specific example, the first metal reflective layers 131, 132 may have a thickness of approximately 10 nm to 30 nm.

[0059] The cavities 141, 142, and 143 between the first metal reflective layers 131 and 132 are resonant layers and may include a dielectric material having a predetermined refractive index, such as, but not limited to, silicon, silicon oxide, silicon nitride, hafnium oxide, or titanium oxide.

[0060] The first, second, and third unit filters 111, 112, and 113 may have different center wavelengths within the first wavelength region. To this end, the first, second, and third unit filters 111, 112, and 113 include first, second, and third cavities 141, 142, and 143 with different thicknesses. FIG. 2 exemplarily illustrates a case in which the second cavity 142 is thicker than the first cavity 141, and the third cavity 143 is thicker than the second cavity 142. In this case, among the first, second, and third unit filters 111, 112, and 113, the third unit filter 113 may have the longest center wavelength, and the first unit filter 111 may have the shortest center wavelength. Depending on the thickness of the cavities, some unit filters may have multiple center wavelengths.

[0061] Each of the fourth, fifth, and sixth unit filters 121, 122, and 123 constituting the second filter array 120 transmits a specific center wavelength within the second wavelength range, and may have a Fabry-Perot structure in which cavities 161, 162, and 163 are provided between two spaced-apart second metal reflective layers 151 and 152. Here, the wavelength band and center wavelength of light passing through the unit filters 121, 122, and 123 are determined depending on the reflection bands of the second metal reflective layers 151 and 152 and the characteristics of the cavities 161, 162, and 163.

[0062] The second metal reflective layers 151, 152 may include a second metal capable of reflecting light in the second wavelength region. For example, the second metal may include, but is not limited to, Cu, Ag, Au, or TiN. The second metal reflective layers 151, 152 may be formed to a thickness of several tens of nanometers, but this is merely exemplary. As a specific example, the second metal reflective layers 151, 152 may have a thickness of approximately 40 nm to 50 nm.

[0063] The second metal constituting the second metal reflective layers 151, 152 may be a metal different from the first metal constituting the first metal reflective layers 131, 132. For example, when the first metal reflective layers 131, 132 contain Al, the second metal reflective layers 151, 152 may contain Cu. Furthermore, when the first metal reflective layers 131, 132 contain Al, the second metal reflective layers 151, 152 may contain Ag. Furthermore, when the first metal reflective layers 131, 132 contain Ag, the second metal reflective layers 151, 152 may contain Cu.

[0064] The cavities 161, 162, and 163 between the second metal reflective layers 151 and 152 are resonant layers and may include a dielectric material having a predetermined refractive index, such as silicon, silicon oxide, silicon nitride, hafnium oxide, or titanium oxide.

[0065] The cavities 161, 162, and 163 provided between the second metal reflective layers 151 and 152 may contain the same material as the cavities 141, 142, and 143 provided between the first metal reflective layers 131 and 132. In this case, the thicknesses of the cavities 161, 162, and 163 provided between the second metal reflective layers 151 and 152 may be different from the thicknesses of the cavities 141, 142, and 143 provided between the first metal reflective layers 131 and 132. In addition, the cavities 161, 162, and 163 provided between the second metal reflective layers 151 and 152 may contain a different material from the cavities 141, 142, and 143 provided between the first metal reflective layers 131 and 132.

[0066] The fourth, fifth, and sixth unit filters 121, 122, and 123 may have different center wavelengths within the second wavelength region. To this end, the fourth, fifth, and sixth unit filters 121, 122, and 123 include fourth, fifth, and sixth cavities 161, 162, and 163 with different thicknesses. FIG. 2 exemplarily illustrates a case in which the fifth cavity 162 is thicker than the fourth cavity 161, and the sixth cavity 163 is thicker than the fifth cavity 162. In this case, among the fourth, fifth, and sixth unit filters 121, 122, and 123, the sixth unit filter 123 may have the longest center wavelength, and the fourth unit filter 121 may have the shortest center wavelength. Depending on the thickness of the cavities, some unit filters may have multiple center wavelengths.

[0067] As described above, by arranging the first filter array 110 having cavities 141, 142, and 143 between the first metal reflective layers 131 and 132 and the second filter array 120 having cavities 161, 162, and 163 between the second metal reflective layers 151 and 152 on a plane, it is possible to realize a spectral filter having characteristics of a wide band (e.g., a wavelength range from ultraviolet to near-infrared) including the first wavelength region and the second wavelength region.

[0068] Figure 3A shows a unit filter 11 in which a TiO2 cavity is provided between Cu reflective layers, and Figure 3B shows a unit filter 21 in which TiO2 dielectric layers are provided on the top and bottom of the structure shown in Figure 3A.

[0069] Figure 4 shows the transmission spectra of the unit filter 11 shown in Figure 3A and the unit filter 21 shown in Figure 3B. In Figure 4, "A" shows the transmission spectrum of the unit filter 11 shown in Figure 3A, and "B" shows the transmission spectrum of the unit filter 21 shown in Figure 3B. Referring to Figure 4, it can be seen that the unit filter 21 shown in Figure 3B has a higher transmittance (degree of transmittance) than the unit filter 11 shown in Figure 3A.

[0070] In this way, by providing a TiO2 dielectric layer on each of the upper and lower parts of the structure in which the TiO2 cavity is provided between the Cu reflective layers, it is possible to realize a unit filter 21 with improved transmittance. Here, the thickness of the TiO2 dielectric layer is also adjusted depending on the center wavelength of the unit filter 21.

[0071] FIG. 5 is a cross-sectional view that schematically illustrates a spectral filter 1200 according to another exemplary embodiment.

[0072] 5, the first filter array 210 includes first, second, and third unit filters 211, 212, and 213 having center wavelengths in a first wavelength region, and the second filter array 220 includes fourth, fifth, and sixth unit filters 221, 222, and 223 having center wavelengths in a second wavelength region.

[0073] The first, second, and third unit filters 211, 212, and 213 constituting the first filter array 210 each include two first metal reflective layers 131 and 132 spaced apart from each other, cavities 141, 142, and 143 provided between the first metal reflective layers 131 and 132, and first and second dielectric layers 171 and 172 provided above and below the cavities 141, 142, and 143. The first, second, and third unit filters 211, 212, and 213 include first, second, and third cavities 141, 142, and 143 of different thicknesses so as to have different center wavelengths within the first wavelength range. The first metal reflective layers 131 and 132 and the first, second, and third cavities 141, 142, and 143 are as described above.

[0074] The first dielectric layer 171 is disposed under the first metal reflective layer 131, and the second dielectric layer 172 is disposed over the first metal reflective layer 132. Here, the first and second dielectric layers 171 and 172 are intended to improve the transmittance of the first, second, and third unit filters 211, 212, and 213. The first and second dielectric layers 171 and 172 may have a single-layer structure. Each of the first and second dielectric layers 171 and 172 may include, for example, titanium oxide, silicon nitride, hafnium oxide, silicon oxide, or a high refractive index polymer, but these are merely examples.

[0075] The thicknesses of the first and second dielectric layers 171, 172 also vary depending on the center wavelengths of the first, second, and third unit filters 211, 212, and 213. Fig. 5 shows an example in which the thicknesses of the first and second dielectric layers 171, 172 increase as the center wavelengths of the unit filters 211, 212, and 213 increase. The thicknesses of the first and second dielectric layers 171, 172 are approximately 10 nm to 20,000 nm, but are not limited to this.

[0076] The fourth, fifth, and sixth unit filters 221, 222, and 223 constituting the second filter array 220 each include two second metal reflective layers 151 and 152 spaced apart from each other, cavities 161, 162, and 163 provided between the second metal reflective layers 151 and 152, and third and fourth dielectric layers 181 and 182 provided above and below the cavities 161, 162, and 163. The fourth, fifth, and sixth unit filters 221, 222, and 223 each include fourth, fifth, and sixth cavities 161, 162, and 163 of different thicknesses so as to have different center wavelengths within the second wavelength range. The second metal reflective layers 151 and 152 and the fourth, fifth, and sixth cavities 161, 162, and 163 are as described above.

[0077] The third dielectric layer 181 is disposed under the second metal reflective layer 151, and the fourth dielectric layer 182 is disposed over the second metal reflective layer 152. Here, the third and fourth dielectric layers 181 and 182 are intended to improve the transmittance of the fourth, fifth, and sixth unit filters 221, 222, and 223. The third and fourth dielectric layers 181 and 182 may have a single-layer structure. Like the first and second dielectric layers 171 and 172 described above, the third and fourth dielectric layers 181 and 182 may each include, but are not limited to, titanium oxide, silicon nitride, hafnium oxide, silicon oxide, or a high refractive index polymer.

[0078] The thicknesses of the third and fourth dielectric layers 181, 182 also vary depending on the center wavelengths of the fourth, fifth, and sixth unit filters 221, 222, and 223. Fig. 5 shows an example in which the thicknesses of the third and fourth dielectric layers 181, 182 increase as the center wavelengths of the unit filters 221, 222, and 223 increase. The thicknesses of the third and fourth dielectric layers 181, 182 are approximately 10 nm to 20,000 nm, but are not limited to this.

[0079] Fig. 6 shows the transmission spectrum of the spectral filter 1200 shown in Fig. 5. Here, the first metal reflective layers 131 and 132 and the second metal reflective layers 151 and 152 are formed of Al and Cu, respectively, and the cavities 141, 142, 143, 161, 162, and 163 are formed of TiO2. The first, second, third, and fourth dielectric layers 171, 172, 181, and 182 are all formed of TiO2. In Fig. 6, "C1" indicates the transmission spectrum of the first filter array 210, and "C2" indicates the transmission spectrum of the second filter array 220.

[0080] FIG. 7 is a cross-sectional view that schematically illustrates a spectral filter 1300 according to yet another exemplary embodiment.

[0081] 7, the first filter array 310 includes at least one unit filter having a center wavelength in a first wavelength range, and the second filter array 320 includes at least one unit filter having a center wavelength in a second wavelength range.

[0082] 7 illustrates, for convenience, an example in which first filter array 310 includes one unit filter (first unit filter 315) and second filter array 320 includes one unit filter (second unit filter 325). If first and second filter arrays 310 and 320 each include multiple unit filters, the multiple unit filters include cavities with different thicknesses.

[0083] The first unit filter 315 constituting the first filter array 310 includes two first metal reflective layers 131 and 132 spaced apart from each other, a first cavity 145 provided between the first metal reflective layers 131 and 132, and first and second dielectric layers 371 and 372 provided at the bottom and top of the first cavity 145, respectively.

[0084] The first dielectric layer 371 is disposed under the first metal reflective layer 131, and the second dielectric layer 372 is disposed on the first metal reflective layer 132. The first and second dielectric layers 371 and 372 may each include, but are not limited to, titanium oxide, silicon nitride, hafnium oxide, silicon oxide, or a high refractive index polymer.

[0085] The first dielectric layer 371 may have a single-layer structure. However, the present invention is not limited thereto, and the first dielectric layer 371 may have a multi-layer structure. The second dielectric layer 372 may have a multi-layer structure. For example, the second dielectric layer 372 may have a structure in which different first and second material layers 372a and 372b are alternately stacked. Here, the thickness and number of material layers constituting the second dielectric layer 372 are also adjusted according to the center wavelength of the first unit filter 315. The second dielectric layer 372 may include three or more different material layers.

[0086] The second unit filter 325 constituting the second filter array 320 includes two second metal reflective layers 151 and 152 spaced apart from each other, a second cavity 165 provided between the second metal reflective layers 151 and 152, and third and fourth dielectric layers 381 and 382 provided at the bottom and top of the second cavity 165, respectively.

[0087] The third dielectric layer 381 is provided below the second metal reflective layer 151, and the fourth dielectric layer 382 is provided above the second metal reflective layer 152. Like the first and second dielectric layers 371 and 372, the third and fourth dielectric layers 381 and 382 may include, but are not limited to, titanium oxide, silicon nitride, hafnium oxide, silicon oxide, or a high refractive index polymer.

[0088] The third dielectric layer 381 may have a single-layer structure or a multi-layer structure. The fourth dielectric layer 382 may have a multi-layer structure. For example, the fourth dielectric layer 382 may have a structure in which different first and second material layers 382a and 382b are alternately stacked. Here, the thickness and number of material layers constituting the fourth dielectric layer 382 are also adjusted depending on the center wavelength of the second unit filter 325. The fourth dielectric layer 382 may include three or more different material layers.

[0089] Fig. 8 is a diagram showing the transmission spectrum of the spectral filter 1300 shown in Fig. 7. Fig. 8 shows the transmission spectrum of the spectral filter 1300 shown in Fig. 7 when the first filter array 310 includes seven unit filters having different center wavelengths and the second filter array 320 includes nine unit filters having different center wavelengths.

[0090] The first metal reflective layers 131, 132 and the second metal reflective layers 151, 152 are formed of Al and Cu, respectively, and the cavities 145, 165 are formed of a multilayer film of TiO2 and SiN. The first and third dielectric layers 371, 381 are formed of SiN, respectively, and the second and fourth dielectric layers 372, 382 are formed of a multilayer film of TiO2 and SiN, respectively. In FIG. 8, "D1" indicates the transmission spectrum of the first filter array 310, and "D2" indicates the transmission spectrum of the second filter array 320. Referring to FIG. 8, it can be seen that the spectral filter 1300 can achieve wideband characteristics and high transmittance.

[0091] 9 is a cross-sectional view schematically illustrating a spectral filter 1400 according to yet another exemplary embodiment. For convenience, FIG. 9 illustrates an example in which the first filter array 410 includes one unit filter (first unit filter 415) and the second filter array 420 includes one unit filter (second unit filter 425).

[0092] The first unit filter 415 constituting the first filter array 410 may include three first metal reflective layers 431, 432, and 433 spaced apart from one another, and two first cavities 441 and 442 provided between the first metal reflective layers 431, 432, and 433.

[0093] The first metal reflective layers 431, 432, 433 may include a first metal capable of reflecting light in a first wavelength region. The first cavities 441, 442 may include a dielectric material such as silicon, silicon oxide, silicon nitride, hafnium oxide, or titanium oxide.

[0094] The second unit filter 425 constituting the second filter array 420 includes three second metal reflective layers 451, 452, and 453 spaced apart from one another, and two second cavities 461 and 462 provided between the second metal reflective layers 451, 452, and 453.

[0095] The second metal reflective layers 451, 452, 453 may include a second metal capable of reflecting light in a second wavelength region. The second cavities 461, 462 may include a dielectric material such as silicon, silicon oxide, silicon nitride, hafnium oxide, or titanium oxide.

[0096] Although the above description has been given of a case where first unit filter 415 includes two cavities 441, 442 and second unit filter 425 includes two cavities 461, 462, it is also possible for each of first and second unit filters 415, 425 to include three or more cavities. Also, although the above description has been given of a case where both first and second unit filters 415, 425 have a multi-cavity structure, it is also possible for one of first and second unit filters 415, 425 to have a single-cavity structure and the other to have a multi-cavity structure.

[0097] Fig. 10 is a cross-sectional view schematically illustrating a spectral filter 1500 according to yet another exemplary embodiment. For convenience, Fig. 10 illustrates an example in which the first filter array 510 includes one unit filter (first unit filter 515) and the second filter array 520 includes one unit filter (second unit filter 525).

[0098] 10, a first unit filter 515 constituting a first filter array 510 includes three first metal reflective layers 431, 432, and 433 spaced apart from one another, two first cavities 441 and 442 provided between the first metal reflective layers 431, 432, and 433, and first and second dielectric layers 571 and 572 provided below and above the first cavities 441 and 442. The first metal reflective layers 431, 432, and 433 and the first cavities 441 and 442 are as described above.

[0099] The first dielectric layer 571 is provided under the first metal reflective layer 431, and the second dielectric layer 572 is provided on the first metal reflective layer 433. Here, the first and second dielectric layers 571 and 572 are intended to improve transmittance and may have a single-layer or multi-layer structure. The first and second dielectric layers 571 and 572 may include, for example, but are not limited to, titanium oxide, silicon nitride, hafnium oxide, silicon oxide, or a high refractive index polymer.

[0100] The second unit filter 525 constituting the second filter array 520 includes three second metal reflective layers 451, 452, and 453 spaced apart from one another, two second cavities 461 and 462 provided between the second metal reflective layers 451, 452, and 453, and third and fourth dielectric layers 581 and 582 provided below and above the second cavities 461 and 462. The second metal reflective layers 451, 452, and 453 and the second cavities 461 and 462 are as described above.

[0101] The third dielectric layer 581 is provided under the second metal reflective layer 451, and the fourth dielectric layer 582 is provided over the second metal reflective layer 453. Here, the third and fourth dielectric layers 581 and 582 may have a single-layer or multi-layer structure and may include, for example, but are not limited to, titanium oxide, silicon nitride, hafnium oxide, silicon oxide, or a high refractive index polymer.

[0102] FIG. 11 is a cross-sectional view that schematically illustrates a spectral filter 1600 according to yet another exemplary embodiment.

[0103] 11, a first filter array 610 includes at least one unit filter having a center wavelength in a first wavelength region, and a second filter array 620 includes at least one unit filter having a center wavelength in a second wavelength region. In FIG. 11, the first filter array 610 includes first, second, and third unit filters 611, 612, and 613, and the second filter array 620 includes fourth, fifth, and sixth unit filters 621, 622, and 623.

[0104] The first, second and third unit filters 611, 612, 613 constituting the first filter array 610 each include two first metal reflective layers 631, 632 spaced apart from each other, and cavities 641, 642, 643 provided between the first metal reflective layers 631, 632. The first metal reflective layers 631, 632 are as described above, and therefore will not be described here.

[0105] The first, second, and third unit filters 611, 612, and 613 may have different center wavelengths within a first wavelength region. To this end, the first, second, and third unit filters 611, 612, and 613 include first, second, and third cavities 641, 642, and 643 having different effective refractive indices. Each of the first, second, and third cavities 641, 642, and 643 includes a first material layer and at least one second material layer disposed within the first material layer and having a refractive index different from that of the first material layer.

[0106] 11 exemplarily illustrates a case where each of the first, second, and third cavities 641, 642, and 643 includes a first material layer and a plurality of second material layers disposed within the first material layer and parallel to each other and perpendicular to the first metal reflective layer 631. Here, each of the first and second material layers may include, for example, silicon, silicon oxide, silicon nitride, or titanium oxide. As a specific example, the first material layer may include silicon oxide, and the second material layer may include titanium oxide.

[0107] The effective refractive index of the first, second, and third cavities 641, 642, and 643 can be changed by adjusting the width of the second material layer. FIG. 11 illustrates an example in which the second material layer is formed so that its width increases from the first cavity 641 to the third cavity 643. In this case, among the first, second, and third cavities 641, 642, and 643, the third cavity 643 may have the highest effective refractive index, and the first cavity 641 may have the lowest effective refractive index. Among the first, second, and third unit filters 611, 612, and 613, the third unit filter 613 may have the longest center wavelength, and the first unit filter 611 may have the shortest center wavelength. Depending on the thickness or effective refractive index of the cavity, some unit filters may have multiple center wavelengths.

[0108] Although the above describes the case where multiple second material layers are arranged vertically to the first metal reflective layer 631, the present invention is not limited to this, and multiple second material layers can also be arranged parallel to the first metal reflective layer 631.

[0109] The fourth, fifth, and sixth unit filters 621, 622, and 623 constituting the second filter array 620 each include two second metal reflective layers 651 and 652 spaced apart from each other, and cavities 661, 662, and 663 provided between the second metal reflective layers 651 and 652. The second metal reflective layers 651 and 652 have been described above, so a description thereof will be omitted.

[0110] The fourth, fifth, and sixth unit filters 621, 622, and 623 may have different center wavelengths within the second wavelength region. To this end, the fourth, fifth, and sixth unit filters 621, 622, and 623 include fourth, fifth, and sixth cavities 661, 662, and 663 having different effective refractive indices. Each of the fourth, fifth, and sixth cavities 661, 662, and 663 includes a first material layer and at least one second material layer disposed within the first material layer and having a refractive index different from that of the first material layer.

[0111] 11 exemplarily shows a case where each of the fourth, fifth, and sixth cavities 661, 662, and 663 includes a first material layer and a plurality of second material layers disposed within the first material layer and parallel to each other and perpendicular to the second metal reflective layer 651. Here, each of the first and second material layers may include, for example, silicon, silicon oxide, silicon nitride, or titanium oxide.

[0112] The effective refractive index of the fourth, fifth, and sixth cavities 661, 662, and 663 can be changed by adjusting the width of the second material layer. FIG. 11 illustrates an example in which the second material layer is formed so that its width increases from the fourth cavity 661 to the sixth cavity 663. In this case, among the fourth, fifth, and sixth cavities 661, 662, and 663, the sixth cavity 663 may have the highest effective refractive index, and the fourth cavity 661 may have the lowest effective refractive index. Among the fourth, fifth, and sixth unit filters 621, 622, and 623, the sixth unit filter 623 may have the longest center wavelength, and the fourth unit filter 621 may have the shortest center wavelength. Depending on the thickness or effective refractive index of the cavity, some unit filters may have multiple center wavelengths.

[0113] The above describes an example in which both first filter array 610 and second filter array 620 have a single-cavity structure. However, both first filter array 610 and second filter array 620 may have a multi-cavity structure. Alternatively, one of first filter array 610 and second filter array 620 may have a single-cavity structure and the other may have a multi-cavity structure.

[0114] 12 is a schematic cross-sectional view of a spectral filter 1700 according to yet another exemplary embodiment. The spectral filter 1700 shown in FIG. 12 is similar to the spectral filter 1600 shown in FIG. 11, except that the cavity further includes an etch stop layer.

[0115] The first, second, and third unit filters 711, 712, and 713 constituting the first filter array 710 include first, second, and third cavities 741, 742, and 743 having different effective refractive indices. Each of the first, second, and third cavities 741, 742, and 743 includes an etch-stop layer 740a disposed on the first metal reflective layer 631, a first material layer disposed on the etch-stop layer 740a, and at least one second material layer disposed within the first material layer. The etch-stop layer 740a facilitates the patterning process for forming the cavities. The etch-stop layer 740a may include, but is not limited to, silicon oxide, titanium oxide, or hafnium oxide.

[0116] The fourth, fifth, and sixth unit filters 721, 722, and 723 constituting the second filter array 720 include fourth, fifth, and sixth cavities 761, 762, and 763 having different effective refractive indices, respectively. Each of the fourth, fifth, and sixth cavities 761, 762, and 763 includes an etching stop layer 760a disposed on the second metal reflective layer 651, a first material layer disposed on the etching stop layer 760a, and at least one second material layer disposed inside the first material layer.

[0117] Fig. 13 is a cross-sectional view schematically illustrating a spectral filter 1800 according to yet another exemplary embodiment. The spectral filter 1800 illustrated in Fig. 13 is similar to the spectral filter 1700 illustrated in Fig. 12, except that first and second dielectric layers 871, 872 are provided below and above the first filter array 810, and third and fourth dielectric layers 881, 882 are provided below and above the second filter array 820.

[0118] 13, first, second, and third unit filters 811, 812, and 813 constituting a first filter array 810 each include two first metal reflective layers 631 and 632 spaced apart from each other, cavities 841, 842, and 843 provided between the first metal reflective layers 631 and 632, and first and second dielectric layers 871 and 872 provided below and above the cavities 841, 842, and 843, respectively. The first, second, and third unit filters 811, 812, and 813 each include first, second, and third cavities 841, 842, and 843 having different effective refractive indices so as to have different center wavelengths within a first wavelength region.

[0119] The first dielectric layer 871 is provided below the first metal reflective layer 631, and the second dielectric layer 872 is provided above the first metal reflective layer 632. Here, the first and second dielectric layers 871 and 872 are intended to improve the transmittance of the first, second, and third unit filters 811, 812, and 813.

[0120] Each of the first and second dielectric layers 871 and 872 includes a first material layer and at least one second material layer disposed within the first material layer and having a refractive index different from that of the first material layer. The first and second material layers may include, but are not limited to, titanium oxide, silicon nitride, hafnium oxide, silicon oxide, or a high-refractive-index polymer. The effective refractive index of the first and second dielectric layers 871 and 872 can be adjusted by changing the width of the second material layer according to the center wavelengths of the first, second, and third unit filters 811, 812, and 813. Each of the first and second dielectric layers 871 and 872 may further include an etch-stop layer.

[0121] The fourth, fifth, and sixth unit filters 821, 822, and 823 constituting the second filter array 820 each include two second metal reflective layers 651 and 652 spaced apart from each other, cavities 861, 862, and 863 provided between the second metal reflective layers 651 and 652, and third and fourth dielectric layers 881 and 882 respectively provided above and below the cavities 861, 862, and 863. The fourth, fifth, and sixth unit filters 821, 822, and 823 each include the fourth, fifth, and sixth cavities 861, 862, and 863 having different effective refractive indices so as to have different center wavelengths within the second wavelength range.

[0122] The third dielectric layer 881 is disposed under the second metal reflective layer 651, and the fourth dielectric layer 822 is disposed over the second metal reflective layer 652. Each of the third and fourth dielectric layers 881 and 882 includes a first material layer and at least one second material layer disposed within the first material layer and having a refractive index different from that of the first material layer. The effective refractive index of the third and fourth dielectric layers 881 and 882 can be adjusted by changing the width of the second material layer according to the center wavelengths of the fourth, fifth, and sixth unit filters 821, 822, and 823. Each of the third and fourth dielectric layers 881 and 882 may further include an etching stop layer.

[0123] FIG. 14 is a cross-sectional view that schematically illustrates a spectral filter 1900 according to yet another exemplary embodiment.

[0124] 14, a first filter array 910 includes at least one unit filter having a center wavelength in a first wavelength range, and a second filter array 920 includes at least one unit filter having a center wavelength in a second wavelength range. In FIG. 14, the first filter array 910 includes first, second, and third unit filters 911, 912, and 913, and the second filter array 920 includes fourth, fifth, and sixth unit filters 921, 922, and 923.

[0125] The first wavelength range is a shorter wavelength range than the second wavelength range. For example, the first wavelength range may include a range of approximately 250 nm to 600 nm, and the second wavelength range may include a range of approximately 600 nm to 1100 nm. However, this is merely an example, and the first and second wavelength ranges can be variously modified depending on design conditions. Alternatively, the first wavelength range may be a longer wavelength range than the second wavelength range.

[0126] Each of the first, second and third unit filters 911, 912, 913 constituting the first filter array 910 transmits a specific center wavelength within the first wavelength region, and may have a Fabry-Perot structure in which cavities 941, 942, 943 are provided between two metal reflective layers 931, 932 spaced apart from each other.

[0127] When light passes through the metal reflective layers 931 and 932 and enters the cavities 941, 942, and 943, the light travels back and forth between the metal reflective layers 931 and 932 and inside the cavities 941, 942, and 943, causing constructive interference and destructive interference in the process. Then, light having a specific center wavelength that satisfies the constructive interference condition is emitted to the outside of the unit filters 911, 912, and 913. Here, the wavelength band and center wavelength of the light passing through the unit filters 911, 912, and 913 are also determined by the reflection bands of the metal reflective layers 931 and 932 and the characteristics of the cavities 941, 942, and 943.

[0128] The metal reflective layers 931, 932 contain a predetermined metal capable of reflecting light in the first wavelength region. When the first wavelength region is a wavelength region shorter than the second wavelength region, the metal reflective layers 931, 932 contain, for example, Al, Ag, Au, or TiN. On the other hand, when the first wavelength region is a wavelength region longer than the second wavelength region, the metal reflective layers 931, 932 contain, for example, Cu, Ag, Au, or TiN. However, this is merely an example. The metal reflective layers 931, 932 are provided to a thickness of approximately several tens of nanometers, but are not limited thereto.

[0129] The cavities 941, 942, and 943 provided between the metal reflective layers 931 and 932 may include, but are not limited to, silicon, silicon oxide, silicon nitride, or titanium oxide. The first, second, and third unit filters 911, 912, and 913 may have different center wavelengths within the first wavelength region. To this end, the first, second, and third unit filters 911, 912, and 913 include first, second, and third cavities 941, 942, and 943 with different thicknesses. Although not shown, the first, second, and third unit filters 911, 912, and 913 may also have different center wavelengths by including cavities with different effective refractive indices.

[0130] Each of the fourth, fifth and sixth unit filters 921, 922, 923 constituting the second filter array 920 transmits a specific center wavelength within the second wavelength region, and may have a Fabry-Perot structure in which cavities 961, 962, 963 are provided between two Bragg reflecting layers 951, 952 spaced apart from each other.

[0131] When light passes through the Bragg reflecting layers 951 and 952 and enters the cavities 961, 962, and 963, the light travels back and forth between the Bragg reflecting layers 951 and 952 and inside the cavities 961, 962, and 963, causing constructive interference and destructive interference in the process. Then, light having a specific center wavelength that satisfies the constructive interference condition is emitted to the outside of the unit filters 921, 922, and 923. Here, the wavelength band and center wavelength of the light passing through the unit filters 911, 912, and 913 are also determined by the reflection bands of the Bragg reflecting layers 951 and 952 and the characteristics of the cavities 961, 962, and 963.

[0132] The Bragg reflecting layers 951 and 952 may also be distributed Bragg reflectors (DBRs). The Bragg reflecting layers 951 and 952 may have a structure in which at least one first material layer 951 a and 952 a and at least one second material layer 951 b and 952 b having different refractive indices are alternately stacked. The first material layer 951 a and 952 a or the second material layer 951 b and 952 b may include, for example, silicon oxide, titanium oxide, silicon nitride, or silicon, but this is merely an example.

[0133] If any one of the first material layers 951a, 952a and the second material layers 951b, 952b constituting the Bragg reflection layers 951, 952 contains, for example, a material (e.g., silicon) that can absorb light in the first wavelength region (e.g., short wavelength light), it is possible to prevent light in the first wavelength region from passing through the fourth, fifth and sixth unit filters 921, 922, 923.

[0134] The cavities 961, 962, 963 provided between the Bragg reflector layers 951, 952 may include, for example but not limited to, silicon, silicon oxide, silicon nitride, hafnium oxide, or titanium oxide.

[0135] The fourth, fifth, and sixth unit filters 921, 922, and 923 may have different center wavelengths within the second wavelength region. To this end, the fourth, fifth, and sixth unit filters 921, 922, and 923 include fourth, fifth, and sixth cavities 961, 962, and 963 of different thicknesses. Meanwhile, although not shown, the fourth, fifth, and sixth unit filters 921, 922, and 923 may also have different center wavelengths by including cavities with different effective refractive indices.

[0136] As described above, by arranging the first filter array 910 having cavities 941, 942, and 943 between the metal reflective layers 931 and 932 and the second filter array 920 having cavities 961, 962, and 963 between the Bragg reflective layers 951 and 952 on a plane, a spectral filter having broadband characteristics including the first wavelength region and the second wavelength region can be realized.

[0137] Fig. 15 is a cross-sectional view schematically illustrating a spectral filter 2000 according to yet another exemplary embodiment. For convenience, Fig. 15 illustrates an example in which the first filter array 1010 includes one unit filter (first unit filter 1015) and the second filter array 1020 includes one unit filter (second unit filter 1025).

[0138] 15, a first unit filter 1015 constituting a first filter array 1010 includes two metal reflective layers 1031 and 1032 spaced apart from each other, and a first cavity 1045 provided between the metal reflective layers 1031 and 1032. The metal reflective layers 1031 and 1032 and the first cavity 1045 are as described above.

[0139] The second unit filter 1025 constituting the second filter array 1020 has a multi-cavity structure. Specifically, the second unit filter 1025 includes three spaced-apart Bragg reflecting layers 1051, 1052, and 1053, and two second cavities 1061 and 1062 disposed between the Bragg reflecting layers 1051, 1052, and 1053. The Bragg reflecting layers 1051, 1052, and 1053 and the second cavities 1061 and 1062 are as described above. The number of first and second material layers constituting each of the Bragg reflecting layers 1051, 1052, and 1053 can vary. While FIG. 15 illustrates the second unit filter 1025 including two cavities 1061 and 1062, the present invention is not limited thereto, and the second unit filter 1025 may include three or more cavities.

[0140] Fig. 16 shows the transmission spectrum of the spectral filter 2000 shown in Fig. 15. Fig. 16 shows the transmission spectrum of the spectral filter 2000 shown in Fig. 15 when the first filter array 1010 includes four unit filters having different center wavelengths and the second filter array 1020 includes four unit filters having different center wavelengths.

[0141] In the first filter array 1010, the metal reflective layers 1031 and 1032 were formed of Al, and the cavity 1045 was formed of a multilayer film of TiO2 and SiN. In the second filter array 1020, the Bragg reflective layers 1051, 1052, and 1053 were formed of Si and SiO2, and the cavities 1061 and 1062 were formed of SiO2. In Figure 16, "S1" indicates the transmission spectrum of the first filter array 1010, and "S2" indicates the transmission spectrum of the second filter array 1020.

[0142] The above describes a case where the first unit filter 1015 has a single-cavity structure and the second unit filter 1025 has a multi-cavity structure. However, it is also possible for the first unit filter 1015 to have a multi-cavity structure and the second unit filter 1025 to have a single-cavity structure. Also, both the first and second unit filters 1015, 1025 may have a multi-cavity structure.

[0143] FIG. 17 is a cross-sectional view that schematically illustrates a spectral filter 2100 according to yet another exemplary embodiment.

[0144] 17, the spectral filter 2100 includes first and second filter arrays 1110 and 1120, and a microlens array 1150 provided in the first and second filter arrays 1110 and 1120. The first filter array 1110 includes first, second, and third unit filters 1111, 1112, and 1113 having center wavelengths in a first wavelength region, and the second filter array 1120 includes fourth, fifth, and sixth unit filters 1121, 1122, and 1123 having center wavelengths in a second wavelength region.

[0145] The first filter array 1110 includes any one of the above-described first filter arrays 110 to 1010, and the second filter array 1120 includes any one of the above-described second filter arrays 120 to 1020. Description of the first and second filter arrays 1110 and 1120 will be omitted.

[0146] A microlens array 1150 including a plurality of microlenses 1150a is provided above the first and second filter arrays 1110 and 1120. The microlenses 1150a focus and direct external light to the corresponding unit filters 1111, 1112, 1113, 1121, 1122, and 1123.

[0147] 17 exemplarily shows a case where microlenses 1150a are provided in one-to-one correspondence with unit filters 1111, 1112, 1113, 1121, 1122, and 1123. However, this is merely an example, and it is also possible to provide a plurality of unit filters 1111, 1112, 1113, 1121, 1122, and 1123 corresponding to one microlens 1150a.

[0148] The spectral filter according to the above embodiment is provided in an image sensor 1000 (FIG. 1), and a pixel array 4100 of the image sensor 1000 receives light transmitted through the spectral filter, converts it into an electrical video signal, and outputs the signal. The video signal output from the pixel array 4100 is then subjected to image processing by a processor 4200 and output. Here, the pixel array 4100 may be provided to correspond to a plurality of unit filters of the spectral filter. The pixel array 4100 is provided to correspond one-to-one with the plurality of unit filters. However, this is not a limitation, and two or more pixels may be provided to correspond to one unit filter.

[0149] FIG. 18 is an exemplary plan view of a spectral filter 9100 applicable to the image sensor 1000 of FIG.

[0150] 18, a spectral filter 9100 includes a plurality of filter groups 9110 arranged two-dimensionally, where each filter group 9110 includes 16 unit filters F1 to F16 arranged in a 4x4 array.

[0151] The first and second unit filters F1 and F2 have center wavelengths UV1 and UV2 in the ultraviolet region, the third through fifth unit filters F3 and F5 have center wavelengths B1 and B3 in the blue region, the sixth through eleventh unit filters F6 and F11 have center wavelengths G1 and G6 in the green region, the twelfth through fourteenth unit filters F12 and F14 have center wavelengths R1 and R3 in the red region, and the fifteenth and sixteenth unit filters F15 and F16 have center wavelengths NIR1 and NIR2 in the near-infrared region.

[0152] Fig. 19 is a plan view of another exemplary spectral filter 9100 applicable to the image sensor of Fig. 1. For convenience, Fig. 19 shows a plan view of one filter group 9120.

[0153] 19, each filter group 9120 includes nine unit filters F1 through F9 arranged in a 3x3 array. The first and second unit filters F1 and F2 have center wavelengths UV1 and UV2 in the ultraviolet range, the fourth, fifth, and seventh unit filters F4, F5, and F7 have center wavelengths B1 through B3 in the blue range, the third and sixth unit filters F3 and F6 have center wavelengths G1 and G2 in the green range, and the eighth and ninth unit filters F8 and F9 have center wavelengths R1 and R2 in the red range.

[0154] Fig. 20 is a plan view of yet another example of a spectral filter 9100 that can be applied to the image sensor of Fig. 1. For convenience, Fig. 20 shows a plan view of one filter group 9130.

[0155] 20, each filter group 9130 includes 25 unit filters F1 through F25 arranged in a 5x5 array. The first through third unit filters F1 through F3 have center wavelengths UV1 through UV3 in the ultraviolet range, the sixth, seventh, eighth, eleventh, and twelfth unit filters F6, F7, F8, F11, and F12 have center wavelengths B1 through B5 in the blue range, the fourth, fifth, and ninth unit filters F4, F5, and F9 have center wavelengths G1 through G3 in the green range, and the tenth, thirteenth, fourteenth, fifteenth, eighteenth, and nineteenth unit filters F10, F13, F14, F15, F18, and F19 have center wavelengths R1 through R6 in the red range. The twentieth, twenty-third, twenty-fourth and twenty-fifth unit filters F20, F23, F24 and F25 have center wavelengths NIR1 to NIR4 in the near-infrared region.

[0156] The image processing method for the video signal output from the pixel array of the image sensor 1000 will now be described.

[0157] FIG. 21 is a plan view illustrating an example of a pixel array 4110 of an image sensor 1000 according to an example embodiment.

[0158] 21, the pixel array 4110 includes a plurality of pixels P1 through P16 arranged two-dimensionally. In FIG. 21, 16 pixels P1 through P16 are arranged in a 4×4 array. In FIG. 21, the first through sixteenth pixels P1 through P16 output image signals ranging from the ultraviolet region to the near-infrared region, but this is merely an example. Here, the plurality of unit filters are arranged such that their center wavelengths are adjacent to each other, but this is not limiting.

[0159] The first and second pixels P1 and P2 can also function as ultraviolet pixels that output video signals in the ultraviolet region. In this case, the unit filters corresponding to the first and second pixels P1 and P2 can have center wavelengths UV1 and UV2 in the ultraviolet region. The third through fifth pixels P3 through P5 can also function as blue pixels that output video signals in the blue region. In this case, the unit filters corresponding to the third through fifth pixels P3 through P5 can have center wavelengths B1 to B3 in the blue region.

[0160] The sixth through eleventh pixels P6 through P11 can also function as green pixels that output video signals in the green light region. In this case, the unit filters corresponding to the sixth through eleventh pixels P6 through P11 can have center wavelengths G1 through G6 in the green light region. The twelfth through fourteenth pixels P12 through P14 can also function as red pixels that output video signals in the red light region. In this case, the unit filters corresponding to the twelfth through fourteenth pixels P12 through P14 can have center wavelengths R1 through R3 in the red light region. The fifteenth and sixteenth pixels P15 and P16 can also function as near-infrared pixels that output video signals in the near-infrared region. In this case, the unit filters corresponding to the fifteenth and sixteenth pixels P15 and P16 can have center wavelengths NIR1 and NIR2 in the near-infrared region.

[0161] 21, the plurality of pixels P1 through P16 can receive light that has passed through the unit filters of the spectral filter, convert it into an electrical image signal, and output it. In this case, the processor 4200 (FIG. 1) can independently perform image processing on each of the image signals output from the plurality of pixels P1 through P16 and output the resulting signal. In this way, by independently performing image processing on each of the image signals output from the plurality of pixels P1 through P16, a spectral image with high resolution can be obtained.

[0162] Figure 22 shows the results obtained when the processor 4200 independently performs image processing on each of the video signals output from the pixels P1 to P16 in the pixel array 4110 shown in Figure 21. Referring to Figure 22, the processor 4200 independently performs image processing on each of the 16 video signals output from the 16 pixels P1 to P16, and as a result, 16 transmission spectra are output.

[0163] Hereinafter, a method for the processor 4200 to perform image processing using a pixel binning technique will be described. The image processing method using the pixel binning technique refers to a method in which the processor 4200 combines two or more video signals output from two or more adjacent pixels and performs image processing. For example, if the pixel array includes a plurality of blue pixels, a plurality of green pixels, and a plurality of red pixels, the processor 4200 may combine at least one of the video signals output from the blue pixels and perform image processing, combine at least one of the video signals output from the green pixels and perform image processing, and combine at least one of the video signals output from the red pixels and perform image processing.

[0164] If the pixel array 4110 further includes a plurality of ultraviolet (UV) pixels, the processor 4200 can combine at least one of the ultraviolet image signals output from the UV pixels and perform image processing. If the pixel array 4110 further includes a plurality of near-infrared (NIR) pixels, the processor 4200 can combine at least one of the image signals output from the near-infrared pixels and perform image processing. The processor 4200 can also combine image signals output from adjacent pixels of different wavelength regions and perform image processing.

[0165] 23 is a diagram illustrating an image processing method according to another exemplary embodiment. Referring to FIG. 23, a pixel array 4110 includes a plurality of pixels P1 through P16 arranged two-dimensionally. The pixels P1 through P16 shown in FIG. 23 are similar to the pixels P1 through P16 shown in FIG. 21, and therefore, a description thereof will be omitted.

[0166] 23, the pixels P1 through P16 can receive light that has passed through the unit filters of the spectral filter, convert the light into an electrical image signal, and output the signal. In this case, the processor 4200 (FIG. 1) can combine two image signals output from two adjacent pixels P1 through P16 into one signal and perform image processing. Here, the unit filters corresponding to the two pixels P1 through P16 that are combined to perform image processing can be arranged so that their center wavelengths are adjacent to each other.

[0167] 23, when the processor 4200 combines two image signals output from two adjacent pixels P1 through P16 and performs image processing, the 16 image signals output from the 16 pixels P1 through P16 are processed as eight image signals and then output by the processor 4200. In this manner, the unit filters corresponding to the two pixels P1 through P16 that are combined and subjected to image processing are arranged so that their center wavelengths are adjacent to each other, thereby enabling eight transmission spectra with high signal strength to be output.

[0168] FIG. 24 is a diagram illustrating an image processing method according to yet another exemplary embodiment.

[0169] 24, a pixel array 4110 includes a plurality of pixels P1 to P16 arranged two-dimensionally. The pixels P1 to P16 shown in FIG. 24 are similar to the pixels P1 to P16 shown in FIG. 21, and therefore, a description thereof will be omitted.

[0170] 24, the pixels P1 through P16 can receive light that has passed through the unit filters of the spectral filter, convert the light into an electrical image signal, and output the signal. In this case, the processor 4200 (FIG. 1) can combine four image signals output from four adjacent pixels P1 through P16 into one signal and perform image processing. Here, the unit filters corresponding to the four pixels P1 through P16 that are combined to perform image processing can be arranged so that their center wavelengths are adjacent to each other.

[0171] 24, when the processor 4200 combines four image signals output from four adjacent pixels P1 through P16 and performs image processing, the 16 image signals output from the 16 pixels P1 through P16 are processed as six image signals and output by the processor 4200. In this manner, the unit filters corresponding to the four pixels P1 through P16 that are combined and subjected to image processing are arranged so that their center wavelengths are adjacent to each other, thereby enabling six transmission spectra with high signal strength to be output.

[0172] Although the above description has been given as an example of two or four pixels P1 to P16 being processed as a single unit, various other numbers of pixels P1 to P16 can be processed as a single unit.

[0173] In image processing of the image signals output from the pixel array 4110, the processor 4200 may perform image processing using the sum or difference of the image signals. In this case, a weight based on a specific wavelength range is applied to at least one of the image signals. However, this is not limited thereto, and the image signals may not be weighted based on a specific wavelength range. In addition to the image processing described above, the processor 4200 may also process and output spectral information for each of the image signals output from the pixel array 4110.

[0174] FIG. 25 is a cross-sectional view that schematically illustrates a spectral filter 2200 according to yet another exemplary embodiment.

[0175] 25, the spectral filter 2200 includes first and second filter arrays 1210 and 1220 and a color filter array 1230. Here, the first and second filter arrays 1210 and 1220 and the color filter array 1230 are disposed on substantially the same plane.

[0176] The first filter array 1210 includes first, second, and third unit filters 1211, 1212, and 1213 having center wavelengths in a first wavelength region, and the second filter array 1220 includes fourth, fifth, and sixth unit filters 1221, 1222, and 1223 having center wavelengths in a second wavelength region. The first filter array 1210 may be any one of the first filter arrays 110 to 1010 described above, and the second filter array 1220 may be any one of the second filter arrays 120 to 1020 described above. Descriptions of the first and second filter arrays 1210 and 1220 will be omitted.

[0177] The color filter array 1230 may include, for example, a red color filter 1231, a green color filter 1232, and a blue color filter 1233. Here, the red color filter 1231 may transmit red light having a wavelength band of approximately 600 nm to 700 nm, the green color filter 1232 may transmit green light having a wavelength band of approximately 500 nm to 600 nm, and the blue color filter 1233 may transmit blue light having a wavelength band of approximately 400 nm to 500 nm. The red, green, and blue color filters 1231, 1232, and 1233 may be color filters commonly used in color display devices such as liquid crystal displays (LCDs) or organic light-emitting display devices (OLEDs). A microlens array 1250 including a plurality of microlenses 1250a may be further provided on top of the first and second filter arrays 1210 and 1220 and the color filter array 1230.

[0178] According to this embodiment, not only can the first and second filter arrays 1210, 1220 be used to obtain information about the center wavelengths of the unit filters 1211, 1212, 1213, 1221, 1222, 1223, but the color filter array 1230 can also be used to obtain information about the wavelengths of red light, green light, and blue light.

[0179] FIG. 26 is a plan view illustrating an example of a pixel array 4120 of an image sensor provided in correspondence with the spectral filter 2200 shown in FIG.

[0180] 26, the pixel array 4120 includes a plurality of pixels P1 to P16 arranged two-dimensionally. In FIG. 26, 16 pixels P1 to P16 are arranged in a 4×4 array.

[0181] For example, the unit filters corresponding to the first and second pixels P1 and P2 have center wavelengths UV1 and UV2 in the ultraviolet range, the unit filters corresponding to the third and fifth pixels P3 and P5 have center wavelengths B1 and B2 in the blue range, the unit filters corresponding to the sixth, seventh, tenth, and eleventh pixels P6, P7, P10, and P11 have center wavelengths G1, G2, G3, and G4 in the green range, the unit filters corresponding to the twelfth and fourteenth pixels P12 and P14 have center wavelengths R1 and R2 in the red range, and the unit filters corresponding to the fifteenth and sixteenth pixels P15 and P16 have center wavelengths NIR1 and NIR2 in the near-infrared range.

[0182] The blue color filter corresponding to the fourth pixel P4 has a central wavelength B in the blue light region, the green color filters corresponding to the eighth and ninth pixels P8 and P9 have a central wavelength G in the green light region, and the red color filter corresponding to the thirteenth pixel P13 has a central wavelength R in the red light region.

[0183] 26, the pixels P1 through P16 can receive light transmitted through the unit filters of the spectral filter, convert the received light into electrical video signals, and output the electrical video signals. The processor 4200 (FIG. 1) can independently perform image processing on the video signals output from the pixels P1, P2, P3, P5, P6, P7, P10, P11, P12, P14, P15, and P16 corresponding to the unit filters. As described above, the processor 4200 can also combine two or more video signals output from the pixels P1, P2, P3, P5, P6, P7, P10, P11, P12, P14, P15, and P16 corresponding to the unit filters and perform image processing on the combined video signals. The processor 4200 can also perform image processing on the video signals output from the pixels P4, P8, P9, and P13 corresponding to the red, green, and blue color filters.

[0184] Figure 27 shows the results obtained by the processor 4200 performing image processing on the video signals output from the plurality of pixels P1 to P16 shown in Figure 26. Referring to Figure 27, twelve transmission spectra are output by independently performing image processing on the video signals output from the pixels P1, P2, P3, P5, P6, P7, P10, P11, P12, P14, P15, and P16 corresponding to the unit filters, and three transmission spectra are output by performing image processing on the video signals output from the pixels P4, P8, P9, and P13 corresponding to the red, green, and blue color filters.

[0185] FIG. 28 is a cross-sectional view that schematically illustrates a spectral filter 2300 according to yet another exemplary embodiment.

[0186] 28, the spectral filter 2300 includes first and second filter arrays 1510 and 1520 and a blank filter 1530. Here, the first and second filter arrays 1510 and 1520 and the blank filter 1530 are provided on substantially the same plane.

[0187] The first filter array 1510 includes first, second, and third unit filters 1511, 1512, and 1513 having center wavelengths in a first wavelength region, and the second filter array 1520 includes fourth, fifth, and sixth unit filters 1521, 1522, and 1523 having center wavelengths in a second wavelength region. The first filter array 1510 may be any one of the first filter arrays 110 to 1010 described above, and the second filter array 1520 may be any one of the second filter arrays 120 to 1020 described above. Descriptions of the first and second filter arrays 1510 and 1520 will be omitted.

[0188] The blank filter 1530 may be a filter that transmits incident light directly. The blank filter 1530 may include, for example, a transparent dielectric material or air. A microlens array 1550 including a plurality of microlenses 1550a may be further provided on top of the first and second filter arrays 1510, 1520 and the blank filter 1530.

[0189] According to this embodiment, not only can information about the central wavelengths of the unit filters 1511, 1512, 1513, 1521, 1522, and 1523 be obtained using the first and second filter arrays 1510 and 1520, but also information about the intensity of light incident on the spectral filters can be obtained using the blank filter 1530.

[0190] FIG. 29 is a plan view illustrating an example of a pixel array 4130 of an image sensor provided in correspondence with the spectral filter 2300 shown in FIG.

[0191] 29, the pixel array 4130 includes a plurality of pixels P1 to P16 arranged two-dimensionally. In FIG. 29, 16 pixels P1 to P16 are arranged in a 4×4 array.

[0192] For example, the unit filter corresponding to the second pixel P2 has a center wavelength UV1 in the ultraviolet region, the unit filters corresponding to the third through fifth pixels P3 through P5 have center wavelengths B1 through B3 in the blue region, the unit filters corresponding to the sixth through eleventh pixels P6 through P11 have center wavelengths G1 through G6 in the green region, the unit filters corresponding to the twelfth through fourteenth pixels P12 through P14 have center wavelengths R1 through R3 in the red region, and the unit filters corresponding to the fifteenth and sixteenth pixels P15 and P16 have center wavelengths NIR1 and NIR2 in the near-infrared region.

[0193] The first pixel P1 is provided corresponding to the blank filter 1530 shown in Fig. 28. Here, the first pixel P1 receives light passing through the blank filter 1530, converts it into an electrical video signal, and outputs it. The processor 4200 (Fig. 1) can perform image processing on the video signal and output it. The video signal output from the first pixel P1 is processed by the processor 4200, resulting in a black and white image in which brightness changes depending on the intensity.

[0194] FIG. 30 shows the results obtained when the processor 4200 performs image processing on the video signals output from the plurality of pixels P1 to P16 shown in FIG.

[0195] Referring to FIG. 30, image processing is performed independently on each of the video signals output from pixels P2 to P16 corresponding to the unit filters, thereby outputting 15 transmission spectra, and image processing is performed on the video signal output from the first pixel P1 corresponding to the blank filter, thereby outputting one transmission spectrum whose intensity varies depending on the wavelength.

[0196] FIG. 31 is a cross-sectional view that schematically illustrates a spectral filter 2300 according to yet another exemplary embodiment.

[0197] 31, the spectral filter 2300 includes first and second filter arrays 1310 and 1320, and an additional filter array 2500 provided on the first and second filter arrays 1310 and 1320. The first filter array 1310 includes first, second, and third unit filters 1311, 1312, and 1313 having center wavelengths in a first wavelength region, and the second filter array 1320 includes fourth, fifth, and sixth unit filters 1321, 1322, and 1323 having center wavelengths in a second wavelength region.

[0198] The first filter array 1310 may be any one of the above-described first filter arrays 110 to 1010, and the second filter array 1320 may be any one of the above-described second filter arrays 120 to 1020. Description of the first and second filter arrays 1310 and 1320 will be omitted.

[0199] The additional filter array 2500 includes a plurality of additional filters 2501, 2502, and 2503. Fig. 31 shows a case in which a first additional filter 2501 is provided corresponding to the first and second unit filters 1311 and 1312, a second additional filter 2502 is provided corresponding to the third and fourth unit filters 1313 and 1321, and a third additional filter 2503 is provided corresponding to the fifth and sixth unit filters 1322 and 1323. However, this is merely an example, and the first, second, and third additional filters 2501, 2502, and 2503 may each be provided corresponding to one unit filter 1311, 1312, 1313, 1321, 1322, and 1323, or may each be provided corresponding to three or more unit filters 1311, 1312, 1313, 1321, 1322, and 1323.

[0200] The first, second, and third additional filters 2501, 2502, and 2503 function to block light of wavelength bands that are not desired by the corresponding unit filters 1311, 1312, 1313, 1321, 1322, and 1323. For example, if the first and second unit filters 1311 and 1312 have center wavelengths of approximately 400 to 500 nm, the first additional filter 2501 is a blue filter that transmits blue light. If the third and fourth unit filters 1313 and 1321 have center wavelengths of approximately 500 to 600 nm, the second additional filter 2502 is a green filter that transmits green light. If the fifth and sixth unit filters 1322 and 1323 have center wavelengths of approximately 600 to 700 nm, the third additional filter 2503 is a red filter that transmits red light.

[0201] The additional filter array 2500 may be a color filter array. In this case, the first, second, and third additional filters 2501, 2502, and 2503 are blue, green, and red color filters, respectively. The blue, green, and red color filters may be color filters typically used in color display devices such as liquid crystal displays or organic light-emitting display devices.

[0202] The additional filter array 2500 may be a wideband filter array, in which case the first, second and third additional filters 2501, 2502, 2503 become first, second and third wideband filters, where each of the wideband filters may have, for example, a multi-cavity structure or a metallic mirror structure.

[0203] FIG. 32 shows an example of a wideband filter 2510 that can be used as the additional filters 2501, 2502, 2503 shown in FIG.

[0204] 32, a wideband filter 2510 includes a plurality of reflective layers 2513, 2514, and 2515 spaced apart from one another, and a plurality of cavities 2511 and 2512 disposed between the reflective layers 2513, 2514, and 2515. Although three reflective layers 2513, 2514, and 2515 and two cavities 2511 and 2512 are shown in FIG. 32 as an example, the numbers of the reflective layers 2513, 2514, and 2515 and the cavities 2511 and 2512 can be varied in various ways.

[0205] Each of the reflective layers 2513, 2514, and 2515 can also be a distributed Bragg reflector (DBR). Each of the reflective layers 2513, 2514, and 2515 can have a structure in which multiple material layers having different refractive indices are alternately stacked. Each of the cavities 2511 and 2512 can include a material having a predetermined refractive index, or can include two or more materials having different refractive indices.

[0206] FIG. 33 shows another example of a wideband filter 2520 that can be used as the additional filters 2501, 2502, and 2503 shown in FIG.

[0207] Referring to FIG. 33, a wideband filter 2520 includes two metal mirror layers 2522 and 2523 spaced apart from each other, and a cavity 2521 provided between the metal mirror layers 2522 and 2523.

[0208] FIG. 34 is a cross-sectional view that schematically illustrates a spectral filter 3000 according to yet another exemplary embodiment.

[0209] Referring to FIG. 34, the spectral filter 3000 includes first and second filter arrays 1410 and 1420, and a short wavelength absorbing filter 1610 and a long wavelength blocking filter 1620 provided in the first and second filter arrays 1410 and 1420.

[0210] The first filter array 1410 includes first, second, and third unit filters 1411, 1412, and 1413 having center wavelengths in a first wavelength region, and the second filter array 1420 includes fourth, fifth, and sixth unit filters 1421, 1422, and 1423 having center wavelengths in a second wavelength region.

[0211] The first filter array 1410 may be any one of the above-described first filter arrays 110 to 1010, and the second filter array 1420 may be any one of the above-described second filter arrays 120 to 1020. Description of the first and second filter arrays 1410 and 1420 will be omitted.

[0212] The short wavelength absorption filter 1610 is provided in some of the unit filters 1411, 1412, 1413, 1421, 1422, and 1423, namely, unit filters 1411, 1413, and 1422, and the long wavelength cutoff filter 1620 is provided in other some of the unit filters 1411, 1412, 1413, 1421, 1422, and 1423, namely, unit filters 1412, 1421, and 1423. FIG. 34 shows a case where the short wavelength absorption filter 1610 and the long wavelength blocking filter 1620 are each provided corresponding to one unit filter 1411, 1412, 1413, 1421, 1422, 1423, but this is not limited thereto, and the short wavelength absorption filter 1610 and the long wavelength blocking filter 1620 can also be provided corresponding to two or more unit filters 1411, 1412, 1413, 1421, 1422, 1423.

[0213] The short wavelength absorption filter 1610 serves to block light of a short wavelength, such as visible light. The short wavelength absorption filter 1610 can be produced, for example, by evaporating silicon, a substance capable of absorbing visible light, onto some of the unit filters 1411, 1413, and 1422 of the unit filters 1411, 1412, 1413, 1421, 1422, and 1423. The unit filters 1411, 1413, and 1422 provided with the short wavelength absorption filter 1610 can transmit near infrared (NIR), which has a wavelength longer than that of visible light.

[0214] The long wavelength blocking filter 1620 serves to block light with long wavelengths, such as near-infrared light. The long wavelength blocking filter 1620 may include a near-infrared blocking filter. The unit filters 1412, 1421, and 1423 provided with the long wavelength blocking filter 1620 can transmit visible light, which has a wavelength shorter than that of near-infrared light.

[0215] According to this embodiment, by providing the short wavelength absorption filter 1610 and the long wavelength blocking filter 1620 in the first and second filter arrays 1410 and 1420, it is possible to fabricate a spectral filter 3000 having wideband characteristics that can be realized from the visible light band to the near-infrared band.

[0216] The image sensor 1000 described above can be employed in a variety of high-performance optical or electronic devices, such as, but not limited to, smartphones, mobile phones, personal digital assistants (PDAs), laptops, personal computers (PCs), various portable devices, home appliances, security cameras, medical cameras, automobiles, Internet of Things (IoT) devices, and other mobile or non-mobile computing devices.

[0217] In addition to the image sensor 1000, the electronic device may further include a processor, for example, an application processor (AP), that controls the image sensor. The processor may run an operating system or application program, control multiple hardware or software components, and perform various data processing and calculations. The processor may further include a graphic processing unit (GPU) and / or an image signal processor. If the processor includes an image signal processor, the image (or video) acquired by the image sensor may be stored and / or output using the processor.

[0218] 35 is a block diagram illustrating an example of an electronic device ED01 including an image sensor 1000. Referring to FIG. 35, in the network environment ED00, the electronic device ED01 can communicate with another electronic device ED02 via a first network ED98 (such as a short-range wireless communication network) or with another electronic device ED04 and / or a server ED08 via a second network ED99 (such as a long-range wireless communication network). The electronic device ED01 can communicate with the electronic device ED04 via the server ED08. The electronic device ED01 includes a processor ED20, a memory ED30, an input device ED50, an audio 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 identity module ED96, and / or an antenna module ED97. The electronic device ED01 may omit some of the components (such as the display device ED60) or add other components. Some of the components may be implemented as a single integrated circuit. For example, the sensor module ED76 (such as a fingerprint sensor, iris sensor, or illuminance sensor) may be implemented by being incorporated into the display device ED60 (such as a display). In addition, if the image sensor 1000 includes a spectroscopic function, some functions of the sensor module (such as a color sensor or illuminance sensor) may be implemented in the image sensor 1000 itself, rather than as a separate sensor module.

[0219] The processor ED20 can execute software (e.g., program ED40) and control one or more other components (e.g., hardware and software components) of the electronic device ED01 coupled to the processor ED20, and can perform various data processing or calculations. As part of the data processing or calculations, the processor ED20 can load instructions and / or data received from other components (e.g., sensor module ED76, communication module ED90) into volatile memory ED32, process the instructions and / or data stored in volatile memory ED32, and store the resulting data in non-volatile memory ED34. The processor ED20 includes a main processor ED21 (e.g., a central processing unit, an application processor) and an auxiliary processor ED23 (e.g., a graphics processing unit, an image signal processor, a sensor hub processor, a communication processor), which can operate independently or together with the main processor ED21. The auxiliary processor ED23 can use less power than the main processor ED21 and can perform specialized functions.

[0220] The auxiliary processor ED23 can control functions and / or states associated with some of the components of the electronic device ED01 (such as the display device ED60, the sensor module ED76, and the communication module ED90) in place of the main processor ED21 while the main processor ED21 is in an inactive state (sleep state), or together with the main processor ED21 while the main processor ED21 is in an active state (application execution state). The auxiliary processor ED23 (such as the image signal processor or the communication processor) can also be embodied as part of other functionally related components (such as the camera module ED80 and the communication module ED90).

[0221] The memory ED30 can store a variety of data required by the components of the electronic device ED01 (such as the processor ED20 and the sensor module ED76). This data includes, for example, input and / or output data for software (such as the program ED40) and its associated instructions. The memory ED30 includes a volatile memory ED32 and / or a non-volatile memory ED34. The non-volatile memory ED34 includes an internal memory ED36 fixedly mounted within the electronic device ED01 and a removable external memory ED38.

[0222] The program ED40 is stored as software in the memory ED30 and includes an operation system ED42, a middleware ED44 and / or an application ED46.

[0223] The input device ED50 can receive instructions and / or data from outside (such as a user) the electronic device ED01 for use by components (such as the processor ED20) of the electronic device ED01. The input device ED50 includes a microphone, a mouse, a keyboard, and / or a digital pen (such as a stylus pen).

[0224] The audio output device ED55 can output audio signals to the outside of the electronic device ED01. The audio output device ED55 includes a speaker and / or a receiver. The speaker can be used for general purposes such as multimedia playback or recording and playback, and the receiver can be used to receive incoming calls. The receiver may be integrated into the speaker or may be implemented as a separate, independent device.

[0225] The display device ED60 can visually provide information outside the electronic device ED01. The display device ED60 includes a display, a holographic device, or a projector, and control circuitry for controlling the device. The display device ED60 includes touch circuitry configured to sense a touch and / or sensor circuitry (such as a pressure sensor) configured to measure the strength of a force generated by the touch. The audio module ED70 can convert sound into an electrical signal or convert an electrical signal into sound. The audio module ED70 can acquire sound via the input device ED50 or output sound via the speakers and / or headphones of the audio output device ED55 and / or other electronic devices (such as the electronic device ED02) directly or wirelessly coupled to the electronic device ED01.

[0226] The sensor module ED76 can sense the operating state (power, temperature, etc.) of the electronic device ED01 or the external environmental state (user state, etc.) and generate an electrical signal and / or a data value corresponding to the sensed state. The sensor module ED76 includes a gesture sensor, a gyro sensor, a barometric pressure sensor, a magnetic sensor, an acceleration sensor, a grip sensor, a proximity sensor, a color sensor, an IR (Infrared) sensor, a biosensor, a temperature sensor, a humidity sensor, and / or an illuminance sensor.

[0227] The interface ED77 may support one or more specified protocols that can be used to connect the electronic device ED01 directly or wirelessly to other electronic devices (such as the electronic device ED02). The interface ED77 may include a High Definition Multimedia Interface (HDMI), a Universal Serial Bus (USB) interface, an SD card interface, and / or an audio interface.

[0228] The connection terminal ED78 includes a connector that allows the electronic device ED01 to be physically connected to another electronic device (such as the electronic device ED02). The connection terminal ED78 includes an HDMI connector, a USB connector, an SD card connector, and / or an audio connector (such as a headphone connector).

[0229] The haptic module ED79 can convert electrical signals into mechanical stimuli (vibrations, movements, etc.) or electrical stimuli that can be perceived by the user through touch or kinesthetic sensation. The haptic module ED79 includes motors, piezoelectric elements, and / or electrical stimulators.

[0230] Camera module ED80 can capture still and video images. Camera module ED80 includes a lens assembly including one or more lenses, image sensor 1000 of FIG. 1, an image signal processor, and / or a flash. The lens assembly included in camera module ED80 can collect light emitted from a subject from which an image is to be captured.

[0231] The power management module ED88 can manage the power supplied to the electronic device ED01. The power management module ED88 can also be embodied as part of a PMIC (Power Management Integrated Circuit).

[0232] The battery ED89 can provide power to the components of the electronic device ED01. The battery ED89 includes a non-rechargeable primary battery, a rechargeable secondary battery, and / or a fuel cell.

[0233] The communication module ED90 can support the establishment of a direct (wired) and / or wireless communication channel between the electronic device ED01 and other electronic devices (such as the electronic device ED02, the electronic device ED04, and the server ED08) and the execution of communication via the established communication channel. The communication module ED90 includes one or more communication processors that operate independently of the processor ED20 (such as an application processor) and support the direct and / or wireless communication. The communication module ED90 includes a wireless communication module ED92 (such as a cellular communication module, a short-range wireless communication module, or a Global Navigation Satellite System (GNSS) communication module) and / or a wired communication module ED94 (such as a local area network (LAN) communication module, a power line communication module, etc.). The appropriate communication module can communicate with other electronic devices via a first network ED98 (such as a short-range communication network like Bluetooth, WiFi Direct, or Infrared Data Association (IrDA)) or a second network ED99 (such as a cellular network, a long-range communication network like the Internet, or a computer network (LAN, WAN, etc.)). Such various types of communication modules may be integrated into one component (such as a single chip) or may be embodied by multiple components (multiple chips) that are separate from one another. The wireless communication module ED92 may use subscriber information (such as an International Mobile Subscriber Identity (IMSI)) stored in the subscriber identity module ED96 to identify and authenticate the electronic device ED01 within a communication network, such as a first network ED98 and / or a second network ED99.

[0234] The antenna module ED97 can transmit signals and / or power to or receive signals from the outside (such as other electronic devices). The antenna includes a radiator made of a conductive pattern formed on a substrate (such as a PCB). The antenna module ED97 includes one or more antennas. When multiple antennas are included, the communication module ED90 selects an antenna from the multiple antennas that is suitable for a communication method used in a communication network such as the first network ED98 and / or the second network ED99. Signals and / or power are transmitted or received between the communication module ED90 and other electronic devices via the selected antenna. In addition to the antenna, other components (such as RFICs (Radio Frequency Integrated Circuits)) may be included as part of the antenna module ED97.

[0235] Some of the components are connected to each other via a peripheral communication method (bus, GPIO (General Purpose Input and Output), SPI (Serial Peripheral Interface), MIPI (Mobile Industry Processor Interface), etc.) and can exchange signals (commands, data, etc.) with each other.

[0236] Commands or data are transmitted 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 may be the same or different types of devices as the electronic device ED01. Some or all of the operations performed by the electronic device ED01 may be performed by one or more of the other electronic devices ED02, ED04, and ED08. For example, when the electronic device ED01 must perform a certain function or service, it may request one or more other electronic devices to perform the function or service in whole or in part, instead of performing the function or service itself. The one or more other electronic devices that receive the request may perform additional functions or services related to the request and transmit the results of their execution to the electronic device ED01. For this purpose, cloud computing, distributed computing, and / or client-server computing technologies may be utilized.

[0237] FIG. 36 is a block diagram illustrating the camera module ED80 of FIG. 35. Referring to FIG. 36, the camera module ED80 includes a lens assembly CM10, a flash CM20, an image sensor 1000 (e.g., shown in FIG. 1), an image stabilizer CM40, a memory CM50 (e.g., a buffer memory), and / or an image signal processor CM60. The lens assembly CM10 can collect light emitted from a subject to be imaged. The camera module ED80 may include multiple lens assemblies CM10, in which case the camera module ED80 may function as a dual camera, a 360° camera, or a spherical camera. Some of the multiple lens assemblies CM10 may have the same lens attributes (e.g., angle of view, focal length, autofocus, F-number, optical zoom, etc.) or different lens attributes. The lens assembly CM10 may include a wide-angle lens or a telephoto lens.

[0238] The flash CM20 can emit light used to enhance light emitted or reflected from a subject. The flash CM20 includes one or more light-emitting diodes (e.g., RGB (Red-Green-Blue) LEDs, White LEDs, Infrared LEDs, Ultraviolet LEDs, etc.) and / or a xenon lamp. The image sensor 1000, which is also the image sensor described in FIG. 1, can capture an image corresponding to the subject by converting light emitted or reflected from the subject and transmitted through the lens assembly CM10 into an electrical signal. The image sensor 1000 may include one or more sensors selected from image sensors with different attributes, such as an RGB sensor, a BW (Black and White) sensor, an IR sensor, or a UV sensor. Each sensor included in the image sensor 1000 may be embodied as a CCD sensor and / or a CMOS sensor.

[0239] The image stabilizer CM40 responds to movement of the camera module ED80 or the electronic device ED01 including it by moving one or more lenses included in the lens assembly CM10 or the image sensor 1000 in a specific direction or by controlling the operating characteristics of the image sensor 1000 (such as adjusting the read-out timing) to compensate for negative effects of the movement. The image stabilizer CM40 can sense the movement of the camera module ED80 or the electronic device ED01 using a gyro sensor (not shown) or an acceleration sensor (not shown) located inside or outside the camera module ED80. The image stabilizer CM40 can also be embodied optically.

[0240] The memory CM50 can store all or part of the data of an image acquired via the image sensor 1000 for subsequent image processing. For example, when multiple images are acquired at high speed, the acquired original data (Bayer-Patterned data, high-resolution data, etc.) can be stored in the memory CM50, and after displaying only the low-resolution image, the original data of the selected (e.g., user-selected) image can be transmitted to the image signal processor CM60. The memory CM50 can be integrated into the memory ED30 of the electronic device ED01 or can be configured as a separate memory operated independently.

[0241] The image signal processor CM60 can perform image processing on images acquired via the image sensor 1000 or image data stored in the memory CM50. The image processing can include depth map generation, 3D modeling, panorama generation, feature point extraction, image synthesis, and / or image compensation (noise reduction, resolution adjustment, brightness adjustment, blurring, sharpening, softening, etc.). The image signal processor CM60 can control (e.g., exposure time control or readout timing control) components included in the camera module ED80 (e.g., image sensor 1000). Images processed by the image signal processor CM60 are stored back in the memory CM50 for further processing or provided to components external to the camera module ED80 (e.g., memory ED30, display device ED60, electronic device ED02, electronic device ED04, server ED08, etc.). The image signal processor CM60 may be integrated into the processor ED20 or may be configured as a separate processor that operates independently of the processor ED20. When the image signal processor CM60 is configured as a separate processor from the processor ED20, the image processed by the image signal processor CM60 can be displayed on the display device ED60 after undergoing additional image processing by the processor ED20.

[0242] The electronic device ED01 includes multiple camera modules ED80 each having different attributes or functions, where one of the multiple camera modules ED80 is a wide-angle camera and another is a telephoto camera, and similarly, one of the multiple camera modules ED80 is a front camera and another is a rear camera.

[0243] According to an exemplary embodiment, an image processing device can be provided that includes a memory and a processor. The memory can store one or more instructions. The processor executes the one or more instructions to receive video signals output from an image sensor that includes a pixel array and a spectral filter including a plurality of unit filters having different center wavelengths, combine two or more of the video signals output from the image sensor into one according to a wavelength range, perform image processing, and output the processed video signal.

[0244] According to an exemplary embodiment, an image processing method can be provided, which includes receiving image signals output from an image sensor including a pixel array and a spectral filter including a plurality of unit filters having different center wavelengths, combining two or more of the image signals output from the image sensor into one according to a wavelength range, and outputting the processed image signal.

[0245] According to an exemplary embodiment, a computer-readable medium having stored thereon a program for performing an image processing method may be provided, the image processing method including receiving image signals output from an image sensor including a pixel array and a spectral filter including a plurality of unit filters having different center wavelengths, combining two or more of the image signals output from the image sensor into one according to a wavelength range, and outputting the processed image signal.

[0246] The image sensor 1000 according to an embodiment may be applied to a mobile phone or smartphone 5100m shown in FIG. 37, a tablet or smart tablet 5200 shown in FIG. 38, a digital camera or camcorder 5300 shown in FIG. 39, a laptop computer 5400 shown in FIG. 40, or a TV or smart TV 5500 shown in FIG. 41. For example, the smartphone 5100m or the smart tablet 5200 may include multiple high-resolution cameras, each equipped with a high-resolution image sensor. The high-resolution cameras may be used to extract depth information of an object in an image, adjust out-of-focus of the image, or automatically identify an object in the image.

[0247] The image sensor 1000 may also be applied to a smart refrigerator 5600 shown in FIG. 42, a security camera 5700 shown in FIG. 43, a robot 5800 shown in FIG. 44, a medical camera 5900 shown in FIG. 45, and the like. For example, the smart refrigerator 5600 may automatically recognize food in the refrigerator using an image sensor and notify a user via a smartphone of whether a specific food is present and the type of food that has been received or removed. The security camera 5700 may provide ultra-high resolution images and utilize high sensitivity to recognize objects or people in images even in dark environments. The robot 5800 may be deployed in disaster or industrial sites where humans cannot directly approach and may provide high-resolution images. The medical camera 5900 may provide high-resolution images for diagnosis or surgery and dynamically adjust its field of view.

[0248] Furthermore, the image sensor 1000 may be applied to a vehicle 6000, as shown in Fig. 46. The vehicle 6000 includes a plurality of vehicle cameras 6010, 6020, 6030, and 6040 arranged at various positions, and each of the vehicle cameras 6010, 6020, 6030, and 6040 includes an image sensor according to an embodiment. The vehicle 6000 may provide a driver with various information about the interior or surroundings of the vehicle 6000 by using the vehicle cameras 6010, 6020, 6030, and 6040, and may automatically recognize objects or people in the image and provide information necessary for autonomous driving.

[0249] Although the image sensor with the spectral filter and the electronic device including the same have been described with reference to the embodiments shown in the drawings, these are merely examples, and those skilled in the art will recognize that various modifications and equivalent embodiments are possible. Therefore, the disclosed embodiments should be considered as illustrative examples, not limiting. The scope of the present invention is defined in the claims, not the above description, and all configurations within the scope of the claims should be construed as being within the scope of the claims, even if they are different from the embodiments. [Industrial Applicability]

[0250] The present invention is applicable to, for example, technical fields related to optical equipment. [Explanation of symbols]

[0251] 110 First filter array 111 1st unit filter 112 Second unit filter 113 Third Unit Filter 120 Second Filter Array 121 4th unit filter 122 5th unit filter 123 6th Unit Filter 131,132 First metal reflective layer 141,142,143,161,162,163 Cavity 151,152 Second metal reflective layer 1000 image sensors 1100 Spectral Filter 4010 Timing Controller 4020 Row Decoder 4030 output circuit 4100 pixel array 4200 processor

Claims

1. a spectral filter including a plurality of unit filters arranged two-dimensionally and having different center wavelengths; a pixel array that receives light transmitted through the spectral filter and outputs a video signal; a processor that performs image processing on the video signal output from the pixel array; the plurality of unit filters include at least one first unit filter having a center wavelength in a first wavelength range and at least one second unit filter having a center wavelength in a second wavelength range; the first unit filter includes a plurality of first metal reflective layers spaced apart from one another and including a first metal; and at least one first cavity provided between the plurality of first metal reflective layers; The image sensor according to claim 1, wherein the second unit filter includes a plurality of Bragg reflection layers spaced apart from each other, and at least one second cavity disposed between the plurality of Bragg reflection layers.

2. 2. The image sensor according to claim 1, wherein the pixel array is provided corresponding to the plurality of unit filters.

3. 3. The image sensor of claim 2, wherein the processor independently performs image processing on each of the image signals output from the pixel array and outputs the processed image signals.

4. 3. The image sensor of claim 2, wherein the processor combines two or more image signals output from the pixel array into one image signal, performs image processing on the combined image signal, and outputs the combined image signal.

5. 5. The image sensor of claim 4, wherein the processor combines two or four image signals output from the pixel array into one image signal, performs image processing on the combined image signal, and outputs the combined image signal.

6. 5. The image sensor of claim 4, wherein the two or more video signals are output from pixels adjacent to each other, and the plurality of unit filters are arranged such that their center wavelengths are adjacent to each other.

7. 2. The image sensor of claim 1, wherein the spectral filter further comprises red, green, and blue color filters disposed on the same plane as the plurality of unit filters.

8. 8. The image sensor according to claim 7, wherein the pixel array is provided corresponding to the plurality of unit filters and the red, green, and blue color filters.

9. 10. The image sensor of claim 8, wherein the processor further performs image processing on the image signals output from the pixels corresponding to the red, green, and blue color filters.

10. 2. The image sensor according to claim 1, wherein the spectral filter further includes a blank filter that is disposed on the same plane as the plurality of unit filters and that transmits incident light as it is.

11. The image sensor according to claim 10 , wherein the pixel array is provided corresponding to the plurality of unit filters and the blank filter.

12. 12. The image sensor of claim 11, wherein the processor further performs image processing on the video signal output from the pixel corresponding to the blank filter.

13. 2. The image sensor of claim 1, wherein the at least one first unit filter forms a first filter array including a plurality of first unit filters having different center wavelengths, and the at least one second unit filter forms a second filter array including a plurality of second unit filters having different center wavelengths.

14. 2. The image sensor of claim 1, wherein the second unit filter includes: a plurality of second metal reflective layers spaced apart from each other and including a second metal different from the first metal; and at least one second cavity disposed between the plurality of second metal reflective layers.

15. 15. The image sensor of claim 14, wherein the center wavelength of the first unit filter is adjusted by changing a thickness or an effective refractive index of the first cavity, and the center wavelength of the second unit filter is adjusted by changing a thickness or an effective refractive index of the second cavity.

16. 15. The image sensor of claim 14, wherein the first unit filter further includes first and second dielectric layers disposed on a lower and upper portion of the first cavity, and the second unit filter further includes third and fourth dielectric layers disposed on a lower and upper portion of the second cavity.

17. 17. The image sensor of claim 16, wherein the thickness or effective refractive index of each of the first and second dielectric layers is adjusted according to the center wavelength of the first unit filter, and the thickness or effective refractive index of each of the third and fourth dielectric layers is adjusted according to the center wavelength of the second unit filter.

18. 2. An image processing method for an image sensor according to claim 1, comprising: The processor performs image processing on the video signal output from the pixel array; The image processing method, wherein the second unit filter includes a plurality of Bragg reflection layers spaced apart from each other, and at least one second cavity disposed between the plurality of Bragg reflection layers.

19. 20. The image processing method of claim 18, wherein the pixel array is provided corresponding to the plurality of unit filters.

20. 20. The image processing method of claim 19, wherein the processor independently performs image processing on each of the image signals output from the pixel array and outputs the processed image signals.

21. 20. The image processing method of claim 19, wherein the processor combines two or more image signals output from the pixel array into one image signal, performs image processing on the combined image signal, and outputs the combined image signal.

22. 22. The image processing method of claim 21, wherein the processor combines two or four image signals output from the pixel array into one image signal, performs image processing on the combined image signal, and outputs the combined image signal.

23. 22. The image processing method of claim 21, wherein the two or more image signals are output from pixels adjacent to each other, and the plurality of unit filters are arranged such that their center wavelengths are adjacent to each other.

24. 20. The image processing method of claim 18, wherein the spectral filter further includes red, green, and blue color filters arranged on the same plane as the plurality of unit filters, and the pixel array is arranged corresponding to the plurality of unit filters and the red, green, and blue color filters.

25. 25. The image processing method of claim 24, wherein the processor further performs image processing on the image signals output from the pixels corresponding to the red, green, and blue color filters.

26. 20. The image processing method of claim 18, wherein the spectral filter further includes a blank filter that is arranged on the same plane as the plurality of unit filters and transmits incident light as is, and the pixel array is arranged corresponding to the plurality of unit filters and the blank filter.

27. 27. The image processing method of claim 26, wherein the processor further performs image processing on the image signal output from the pixel corresponding to the blank filter.

28. 20. The image processing method of claim 18, wherein the second unit filter includes: a plurality of second metal reflective layers spaced apart from each other and including a second metal different from the first metal; and at least one second cavity disposed between the plurality of second metal reflective layers.

29. a spectral filter including a plurality of unit filters having different center wavelengths; a pixel array that receives light transmitted through the spectral filter and outputs a video signal; a processor that performs image processing on the video signal output from the pixel array; the processor combines two or more image signals output from the pixel array into one image signal, performs image processing on the combined image signal, and outputs the combined image signal; the plurality of unit filters include at least one first unit filter having a center wavelength in a first wavelength range and at least one second unit filter having a center wavelength in a second wavelength range; the first unit filter includes a plurality of first metal reflective layers spaced apart from one another and including a first metal; and at least one first cavity provided between the plurality of first metal reflective layers; The image sensor according to claim 1, wherein the second unit filter includes a plurality of Bragg reflection layers spaced apart from each other, and at least one second cavity disposed between the plurality of Bragg reflection layers.

30. 30. The image sensor of claim 29, wherein the pixel array includes a plurality of blue pixels, a plurality of green pixels, and a plurality of red pixels.

31. 31. The image sensor of claim 30, wherein the processor combines at least one of the image signals output from the blue pixels and performs image processing, combines at least one of the image signals output from the green pixels and performs image processing, and combines at least one of the image signals output from the red pixels and performs image processing.

32. 32. The image sensor of claim 31, wherein the pixel array further comprises a plurality of ultraviolet (UV) pixels.

33. 33. The image sensor of claim 32, wherein the processor combines at least one of the ultraviolet image signals output from the ultraviolet pixels and performs image processing.

34. 32. The image sensor of claim 31, wherein the pixel array further comprises a plurality of near-infrared (NIR) pixels.

35. 35. The image sensor of claim 34, wherein the processor combines at least one of the image signals output from the near-infrared pixels and performs image processing.

36. 30. The image sensor of claim 29, wherein the processor further processes and outputs spectral information for each of the video signals output from the pixel array.

37. 30. The image sensor of claim 29, wherein the processor applies a weight according to a specific wavelength region to at least one of the image signals output from the pixel array, and then performs image processing using a sum or a difference of the image signals.

38. 2. The image sensor of claim 1, further comprising a timing controller, a row decoder, and an output circuit.

39. 39. An electronic device comprising an image sensor according to any one of claims 1 to 17 and claims 29 to 38.

40. 40. The electronic device of claim 39, wherein the electronic device is a mobile phone, a smartphone, a tablet, a smart tablet, a digital camera, a camcorder, a laptop, a TV, a smart TV, a smart refrigerator, a security camera, a robot, or a medical camera.

Images