Spectral filters, as well as image sensors and electronic devices that include spectral filters.

Abstract

A spectral filter is provided, along with an image sensor and an electronic device, both of which include the spectral filter. The spectral filter includes a first and second metallic reflective layer spaced apart from each other, a plurality of cavities disposed between the first and second metallic reflective layers, and a bandpass filter disposed between the plurality of cavities and selectively transmitting light in a specific wavelength region. Each of the plurality of cavities may have a multimode structure having multiple center wavelengths.

Description

[0001] Cross-reference to related applications

[0002] This application is based on and claims priority to Korean Patent Application No. 10-2021-0052531 filed with the Korean Intellectual Property Office on April 22, 2021, and Korean Patent Application No. 10-2022-0032230 filed with the Korean Intellectual Property Office on March 15, 2022, the entire disclosure of which is incorporated herein by reference. Technical Field

[0003] This disclosure relates to a spectral filter, an image sensor, and an electronic device, wherein both the image sensor and the electronic device include the spectral filter. Background Technology

[0004] In related technologies, image sensors divide the wavelength band into three parts: red (R), green (G), and blue (B). However, to improve color accuracy and object recognition performance, it is necessary to develop image sensors with spectral filters that divide the wavelength band into more parts. Existing spectral filters have been used in dedicated cameras that include large and complex optical components, and research and development on image sensors with spectral filters integrated on semiconductor chips is ongoing. Summary of the Invention

[0005] A spectral filter is provided, as well as an image sensor and an electronic device, wherein both the image sensor and the electronic device include the spectral filter.

[0006] Additional aspects will be set forth in part in the description which follows, and will also be apparent in part from the description, or may be learned by practicing the embodiments presented in this disclosure.

[0007] According to one aspect of the embodiments, a spectral filter includes: a first metal reflective layer; a second metal reflective layer disposed above the first metal reflective layer; a plurality of cavities disposed between the first and second metal reflective layers, each cavity having a plurality of center wavelengths; and a bandpass filter disposed below the first metal reflective layer or above the second metal reflective layer, and including a plurality of band filters that transmit light in different wavelength regions, wherein the plurality of band filters are arranged to correspond to the plurality of cavities, each of the plurality of band filters transmits light in a specific wavelength region, and each of the plurality of cavities corresponding to each of the plurality of band filters has a plurality of center wavelengths including the center wavelength in the specific wavelength region.

[0008] Bandpass filters can include color filters or broadband filters.

[0009] Multiple frequency band filters can be configured to correspond one-to-one with multiple cavities.

[0010] Multiple frequency band filters may include a first frequency band filter that transmits light in a first wavelength region, a second frequency band filter that transmits light in a second wavelength region, and a third frequency band filter that transmits light in a third wavelength region.

[0011] The multiple cavities may include a first cavity corresponding to a first frequency band filter, a second cavity corresponding to a second frequency band filter, and a third cavity corresponding to a third frequency band filter.

[0012] The first cavity may have multiple center wavelengths including a center wavelength in a first wavelength region, the second cavity may have multiple center wavelengths including a center wavelength in a second wavelength region, and the third cavity may have multiple center wavelengths including a center wavelength in a third wavelength region.

[0013] The first to third cavities can have different effective refractive indices.

[0014] The first to third cavities can have the same thickness.

[0015] Each of the first to third cavities may have a thickness greater than or equal to about 200 nm and less than or equal to about 1000 nm.

[0016] At least one of the first to third cavities may include a substrate and at least one pattern arranged in a specific shape in the substrate.

[0017] The substrate of each of the first to third cavities may include titanium oxide.

[0018] The substrate of each of the first through third cavities may include silicon nitride or hafnium oxide. Each of the multiple frequency band filters may be configured to correspond to two or more cavities.

[0019] The first and second metal reflective layers may be made of the same metal material or different metal materials.

[0020] The first and second metal reflective layers may include Al, Cu, Ag, Au, Ti, W, or TiN. The first or second metal reflective layer may also include polycrystalline silicon.

[0021] Each of the first and second metal reflective layers can have a thickness of about 10 nm to about 80 nm.

[0022] The spectral filter may also include multiple dielectric layers arranged above or below multiple cavities, with different effective refractive indices.

[0023] According to one aspect of another embodiment, an image sensor includes: a spectral filter; and a pixel array for receiving light transmitted through the spectral filter, wherein the spectral filter further includes: a first metallic reflective layer; a second metallic reflective layer disposed above the first metallic reflective layer; a plurality of cavities disposed between the first and second metallic reflective layers, each cavity having a plurality of center wavelengths; and a bandpass filter disposed below the first metallic reflective layer or above the second metallic reflective layer, and including a plurality of band filters selectively transmitting light in different wavelength regions, wherein the plurality of band filters are arranged corresponding to the plurality of cavities, each of the plurality of band filters transmitting light in a specific wavelength region, and each of the plurality of cavities corresponding to each of the plurality of band filters having a plurality of center wavelengths including a center wavelength in the specific wavelength region.

[0024] The pixel array may include multiple pixels, and each pixel may include a wiring layer and a photodiode disposed on the wiring layer, the wiring layer including driving circuitry.

[0025] Multiple frequency band filters may include a first frequency band filter that transmits light in a first wavelength region, a second frequency band filter that transmits light in a second wavelength region, and a third frequency band filter that transmits light in a third wavelength region.

[0026] The multiple cavities may include a first cavity corresponding to a first frequency band filter, a second cavity corresponding to a second frequency band filter, and a third cavity corresponding to a third frequency band filter.

[0027] The first cavity may have multiple center wavelengths including a center wavelength in a first wavelength region, the second cavity may have multiple center wavelengths including a center wavelength in a second wavelength region, and the third cavity may have multiple center wavelengths including a center wavelength in a third wavelength region.

[0028] The first to third cavities can have different effective refractive indices.

[0029] The first to third cavities can have the same thickness.

[0030] At least one of the first to third cavities may include a substrate and at least one pattern arranged in a specific shape in the substrate.

[0031] The spectral filter may also include multiple dielectric layers arranged above or below multiple cavities, with different effective refractive indices.

[0032] Image sensors may also include timing controllers, line decoders, and output circuitry.

[0033] According to one aspect of another embodiment, an electronic device includes the image sensor described above.

[0034] Electronic devices may include mobile phones, smartphones, tablet computers, smart tablet computers, digital cameras, camcorders, laptop computers, televisions, smart TVs, smart refrigerators, security cameras, robots, or medical cameras.

[0035] According to another aspect of the embodiments, a spectral filter includes: a first metal reflective layer; a second metal reflective layer disposed above the first metal reflective layer; a plurality of cavities disposed between the first and second metal reflective layers; and a bandpass filter disposed below the first metal reflective layer or above the second metal reflective layer. The bandpass filter includes a plurality of frequency band filters that transmit light in a plurality of wavelength regions, wherein the plurality of frequency band filters are configured to correspond to the plurality of cavities, each of the plurality of frequency band filters transmits light in a corresponding wavelength region, and each of the plurality of cavities corresponding to each of the plurality of frequency band filters has a plurality of corresponding center wavelengths, the plurality of corresponding center wavelengths including corresponding center wavelengths in the corresponding wavelength regions.

[0036] According to another aspect of another embodiment, a spectral filter includes: a resonator array including: a first metal reflective layer; a second metal reflective layer; and a plurality of multimode cavities disposed between the first and second metal reflective layers, the plurality of multimode cavities having uniform thickness; and a filter array disposed below or above the resonator array, the filter array including a plurality of filters that transmit light in a plurality of wavelength regions, wherein one of the plurality of filters corresponds to one or more of the plurality of multimode cavities, and the one filter transmits light in one of the plurality of wavelength regions, and wherein one of the plurality of multimode cavities has a plurality of center wavelengths including a center wavelength in one of the plurality of wavelength regions of the one filter.

[0037] In a spectral filter, one of the multiple multimode cavities includes a first dielectric pattern, such that the multiple multimode cavities have a first effective refractive index; and another of the multiple multimode cavities includes a second dielectric pattern, such that the other of the multiple multimode cavities has a second effective refractive index. Attached Figure Description

[0038] The above and other aspects, features, and characteristics of some embodiments of this disclosure will become clearer from the following description taken in conjunction with the accompanying drawings, in which:

[0039] Figure 1 This is a schematic diagram of a cross-section of an image sensor according to an example embodiment;

[0040] Figure 2 This is a cross-sectional view of the spectral filter according to an example embodiment;

[0041] Figures 3A to 3C yes Figure 2 A diagram showing examples of the transmission spectra of the first bandpass filter, the second bandpass filter, and the third bandpass filter in the spectral filter;

[0042] Figure 4 yes Figure 2 A diagram illustrating an example of a bandpass filter;

[0043] Figure 5 yes Figure 2 A diagram of another example of a bandpass filter;

[0044] Figures 6A to 6C yes Figure 2 A diagram showing examples of the transmission spectra of the first, second, and third cavities in a spectral filter;

[0045] Figure 7 This is a diagram of a spectral filter according to another example embodiment;

[0046] Figure 8A and Figure 8B It shows Figure 7 Simulation results of the transmission spectra of the first and second cavities in the spectral filter;

[0047] Figure 9A It shows the way Figure 7 Simulation results of the absorption spectra detected by the spectral filter in the first and second pixels;

[0048] Figure 9B It shows the way Figure 7 Simulation results of the absorption spectra detected by the spectral filter in the third and fourth pixels;

[0049] Figure 9C It shows the way Figure 7 Simulation results of the absorption spectra detected by the spectral filter in the fifth and sixth pixels;

[0050] Figure 9D It shows the way Figure 7 Simulation results of the absorption spectra detected by the spectral filter in the seventh and eighth pixels;

[0051] Figure 10 This is a diagram of a spectral filter according to another example embodiment;

[0052] Figure 11 This is a diagram of a spectral filter according to another example embodiment;

[0053] Figure 12 This is a block diagram of an image sensor according to an example embodiment;

[0054] Figure 13 It is applicable Figure 12 A planar diagram of an example spectral filter for an image sensor;

[0055] Figure 14 It is applicable Figure 12 A planar view of another example of a spectral filter for an image sensor;

[0056] Figure 15 It is applicable Figure 12 A planar view of another example of a spectral filter for an image sensor;

[0057] Figure 16 This is a schematic block diagram of an electronic device including an image sensor according to an example embodiment;

[0058] Figure 17 yes Figure 16 A schematic block diagram of the camera module; and

[0059] Figures 18 to 19 These are figures illustrating various examples of electronic devices employing image sensors according to exemplary embodiments. Detailed Implementation

[0060] Referring now to the embodiments, examples of which are shown in the accompanying drawings, wherein similar reference numerals throughout the drawings denote similar elements. In this respect, the presented embodiments may take different forms and should not be construed as limited to the description set forth herein. Therefore, the embodiments are described below only with reference to the accompanying drawings to explain various aspects. The term “and / or” as used herein includes any and all combinations of one or more of the associated listed items. Expressions such as “at least one of…” modify the entire list of elements when following a list of elements, rather than modifying individual elements in the list. For example, the expression “at least one of a, b, and c” should be understood to include only a, only b, only c, both a and b, both a and c, both b and c, all of a, b, and c, or variations thereof.

[0061] In the context of describing the embodiments (especially in the context of the appended claims), the use of the terms “a,” “an,” “the,” and similar designations should be interpreted to cover both the singular and the plural. Unless otherwise indicated herein or clearly contradicted by the context, all methods described herein may be performed in any suitable order, and the embodiments are not limited to the described order of operations.

[0062] Furthermore, the terms "component," "module," etc., refer to a unit that performs at least one function or operation, and can be implemented using hardware, software, or a combination thereof.

[0063] The connecting lines or connectors shown in the various accompanying drawings are intended to illustrate exemplary functional relationships and / or physical or logical couplings between various elements, and therefore it should be noted that many alternative or additional functional relationships, physical connections or logical connections may exist in actual devices.

[0064] Any and all examples or examples of language used herein are intended only to better illustrate technical concepts and do not impose limitations on the scope of the embodiments unless otherwise required.

[0065] Figure 1 This is a schematic diagram of a cross-section of an image sensor 1000 according to an example embodiment. Figure 1 The image sensor 1000 may include, for example, a complementary metal-oxide-semiconductor (CMOS) image sensor or a charge-coupled device (CCD) image sensor.

[0066] refer to Figure 1 The image sensor 1000 may include a pixel array 65 and a resonator structure 80 disposed on the pixel array 65. The pixel array 65 may include a plurality of pixels arranged in a two-dimensional (2D) manner, and the resonator structure 80 (e.g., a resonator array) may include a plurality of resonators disposed corresponding to the plurality of pixels.

[0067] Each pixel of the pixel array 65 may include a photodiode 62 as a photoelectric conversion element and a driving circuit 52 for driving the photodiode 62. The photodiode 62 may be embedded in a semiconductor substrate 61. The semiconductor substrate 61 may be, for example, a silicon substrate. However, this disclosure is not limited thereto. A wiring layer 51 may be disposed on the lower surface 61a of the semiconductor substrate 61, and the driving circuit 52 (e.g., a metal-oxide-semiconductor field-effect transistor (MOSFET)) may be disposed in the wiring layer 51.

[0068] A resonator structure 80, comprising multiple resonators, can be disposed above a semiconductor substrate 61. Each resonator can be arranged to transmit light in a specific desired wavelength region. Each resonator may include a first reflective layer 81 and a second reflective layer 82 spaced apart from each other, and cavities 83a, 83b, 83c, and 83d disposed between the first reflective layer 81 and the second reflective layer 82. Each reflective layer in the first reflective layer 81 and the second reflective layer 82 may include, for example, a metallic reflective layer or a Bragg reflective layer. Each cavity in cavities 83a, 83b, 83c, and 83d can be arranged to induce resonance of light in a specific desired wavelength region.

[0069] A first functional layer 71 may be disposed between the upper surface 61b of the semiconductor substrate 61 and the resonator structure 80. The first functional layer 71 can improve the transmittance of light incident on the photodiode 62 by passing through the resonator structure 80. For this purpose, the first functional layer 71 may include a dielectric layer or a dielectric pattern with an adjusted refractive index.

[0070] The second functional layer 72 can be disposed on the upper surface of the resonator structure 80. The second functional layer 72 can improve the transmittance of light incident on the resonator structure 80. For this purpose, the second functional layer 72 may include a dielectric layer or a dielectric pattern with an adjusted refractive index. The third functional layer 90 may also be disposed on the upper surface of the second functional layer 72. The third functional layer 90 may include, for example, an anti-reflective layer, a focusing lens, a color filter, a short-wavelength absorption filter, a long-wavelength cutoff filter, etc. However, this is only an example.

[0071] At least one of the first functional layer 71, the second functional layer 72, and the third functional layer 90 can, together with the resonator structure 80, constitute the spectral filter described below. The spectral filter according to the example embodiment will be described in detail below.

[0072] The following describes in detail a spectral filter suitable for an image sensor 1000 according to an exemplary embodiment. The spectral filter according to the exemplary embodiment can detect light having a wavelength range of about 350 nm to about 1000 nm or a wavelength range of about 350 nm to about 1500 nm. However, this disclosure is not limited thereto.

[0073] Figure 2 This is a cross-sectional view of the spectral filter 1100 according to an example embodiment. Figure 2 An example is shown of light incident on a spectral filter 1100 in the first to third wavelength regions. Here, the first wavelength region may include a first wavelength λ1, a first wavelength λ1' and a first wavelength λ1'", the second wavelength region may include a second wavelength λ2, a second wavelength λ2' and a second wavelength λ2'", and the third wavelength region may include a third wavelength λ3, a third wavelength λ3' and a third wavelength λ3'.

[0074] refer to Figure 2 The spectral filter 1100 may include multiple filters (i.e., a first filter 111, a second filter 112, and a third filter 113) arranged in a two-dimensional (2D) manner, such as a filter array. A pixel array 4100, including multiple pixels (i.e., a first pixel 101, a second pixel 102, and a third pixel 103) corresponding to the first filter 111, the second filter 112, and the third filter 113 respectively, may be disposed below the spectral filter 1100. Figure 2 The diagram illustrates the case where there are three filters (i.e., first filter 111, second filter 112, and third filter 113) and three pixels (i.e., first pixel 101, second pixel 102, and third pixel 103).

[0075] Although the first filter 111, the second filter 112, and the third filter 113 may be arranged on substantially the same plane, this disclosure is not limited thereto. The first filter 111 may have a center wavelength in a first wavelength region. The first wavelength region may be in the range of, for example, about 350 nm to about 500 nm. However, this is merely exemplary, and the first wavelength region may also have various wavelength ranges depending on design considerations.

[0076] The second filter 112 may have a center wavelength in a second wavelength region. The second wavelength region may be longer than the first wavelength region. The second wavelength region may be in the range of, for example, about 500 nm to about 650 nm; however, such a range is provided only as an example. The third filter 113 may have a center wavelength in a third wavelength region. The third wavelength region may be longer than the second wavelength region. The third wavelength region may be in the range of, for example, about 650 nm to about 800 nm; however, such a range is provided only as an example.

[0077] The first filter 111, the second filter 112, and the third filter 113 may include a resonator 140 and a bandpass filter 150 disposed above the resonator 140. The resonator 140 (e.g., a resonator array) may include a first cavity 141, a second cavity 142, and a third cavity 143, and the bandpass filter 150 may include a first band filter 151, a second band filter 152, and a third band filter 153.

[0078] The resonator 140 may have a Fabry-Perot structure. Specifically, the resonator 140 may include a first metal reflective layer 131 and a second metal reflective layer 132 spaced apart from each other, and a first cavity 141, a second cavity 142, and a third cavity 143 disposed between the first metal reflective layer 131 and the second metal reflective layer 132. Each of the first cavity 141, the second cavity 142, and the third cavity 143 may have a multimode cavity structure with multiple center wavelengths as described below.

[0079] When light passes through the second metal reflective layer 132 and is incident on each of the first cavity 141, the second cavity 142, and the third cavity 143, the light can be internally reflected between the first metal reflective layer 131 and the second metal reflective layer 132 within the first cavity 141, the second cavity 142, and the third cavity 143, during which constructive interference and destructive interference occur. In each of the first cavity 141, the second cavity 142, and the third cavity 143, light with a specific center wavelength that satisfies the constructive interference condition can be output through the first metal reflective layer 131 and incident on each of the first pixel 101, the second pixel 102, and the third pixel 103 of the pixel array 4100.

[0080] A lower dielectric layer 170 may be disposed between the resonator 140 and the pixel array 4100, and an upper dielectric layer 180 may be disposed between the resonator 140 and the bandpass filter 150. The lower dielectric layer 170 and the upper dielectric layer 180 may comprise transparent dielectric materials that increase the transmittance of the center wavelength. The lower dielectric layer 170 and the upper dielectric layer 180 may comprise, for example, titanium oxide, silicon nitride, hafnium oxide, silicon oxide, high refractive index polymers, etc.; however, this disclosure is not limited thereto.

[0081] The first filter 111 may further include a first cavity 141 disposed between the first metal reflective layer 131 and the second metal reflective layer 132, and a first frequency band filter 151 disposed above the first cavity 141. The second filter 112 may further include a second cavity 142 disposed between the first metal reflective layer 131 and the second metal reflective layer 132, and a second frequency band filter 152 disposed above the second cavity 142. The third filter 113 may further include a third cavity 143 disposed between the first metal reflective layer 131 and the second metal reflective layer 132, and a third frequency band filter 153 disposed above the third cavity 143.

[0082] Each of the first band filter 151, the second band filter 152, and the third band filter 153 can transmit light in a specific wavelength range and block light in other wavelength ranges. Figures 3A to 3CExamples of the transmission spectra of the first band filter 151, the second band filter 152, and the third band filter 153 are shown. Figure 3A The transmission spectrum of the first band filter 151 is shown, and the first band filter 151 can transmit light in the first wavelength region. Figure 3B The transmission spectrum of the second band filter 152 is shown, and the second band filter 152 can transmit light in the second wavelength region. Figure 3C The transmission spectrum of the third-band filter 153 is shown, and the third-band filter 153 can transmit light in the third wavelength region.

[0083] exist Figure 2 In the spectral filter 1100, when light from the first wavelength region, the second wavelength region, and the third wavelength region is incident on the bandpass filter 150, the light from the first wavelength region with wavelengths λ1, λ1', and λ1" can pass through the first band filter 151. The light from the second wavelength region with wavelengths λ2, λ2', and λ2" can pass through the second band filter 152, and the light from the third wavelength region with wavelengths λ3, λ3', and λ3" can pass through the third band filter 153.

[0084] For example, a color filter can be used as a bandpass filter 150. For instance, the color filter can be a typical color filter used in color display devices such as liquid crystal displays and organic light-emitting diode displays. In this case, the first band filter 151 can be a blue color filter, the second band filter 152 can be a green color filter, and the third band filter 153 can be a red color filter.

[0085] In addition to the color filters described above, a broadband pass filter can also be used as a bandpass filter 150. In this case, the first band filter 151, the second band filter 152, and the third band filter 153 can be a first broadband filter, a second broadband filter, and a third broadband filter, respectively. Each of the first to third broadband filters can have, for example, a multi-cavity structure or a metal mirror structure.

[0086] Figure 4 This is a diagram of an example of a broadband filter. (Reference) Figure 4 The broadband filter 2510 may include a plurality of reflective layers spaced apart from each other (i.e., a first reflective layer 2513, a second reflective layer 2514 and a third reflective layer 2515), and a plurality of cavities disposed between the first reflective layer 2513, the second reflective layer 2514 and the third reflective layer 2515 (i.e., a first cavity 2511 and a second cavity 2512). Figure 4Three reflective layers (i.e., first reflective layer 2513, second reflective layer 2514 and third reflective layer 2515) and two cavities (i.e. first cavity 2511 and second cavity 2512) are shown; however, the number of reflective layers and cavities can vary.

[0087] The first reflective layer 2513, the second reflective layer 2514, and the third reflective layer 2515 can be spaced apart from each other. The first cavity 2511 can be disposed between the first reflective layer 2513 and the second reflective layer 2514, and the second cavity 2512 can be disposed between the second reflective layer 2514 and the third reflective layer 2515.

[0088] Each cavity in the first cavity 2511 and the second cavity 2512 may include a material having a specific refractive index. Each cavity in the first cavity 2511 and the second cavity 2512 may include two or more materials with different refractive indices.

[0089] Each of the first reflective layer 2513, the second reflective layer 2514, and the third reflective layer 2515 may be a Bragg reflector. The Bragg reflector may be a distributed Bragg reflector (DBR). Each of the first reflective layer 2513, the second reflective layer 2514, and the third reflective layer 2515 may have a structure in which, for example, multiple material layers with different refractive indices are alternately stacked.

[0090] Figure 5 This is a diagram of another example of a broadband filter. (Reference) Figure 5 The broadband filter 2520 may include a first metal mirror layer 2522 and a second metal mirror layer 2523 spaced apart from each other, and a cavity 2521 disposed between the first metal mirror layer 2522 and the second metal mirror layer 2523.

[0091] Return to reference Figure 2 The first cavity 141, the second cavity 142, and the third cavity 143 may be disposed between the first metal reflective layer 131 and the second metal reflective layer 132. The first metal reflective layer 131 and the second metal reflective layer 132 may comprise a metallic material capable of reflecting light in a specific wavelength region. The first metal reflective layer 131 and the second metal reflective layer 132 may comprise, for example, Al, Cu, Ag, Au, Ti, W, TiN, etc.; however, this disclosure is not limited thereto. The first metal reflective layer 131 and the second metal reflective layer 132 may also comprise polycrystalline silicon.

[0092] The first metal reflective layer 131 and the second metal reflective layer 132 may comprise the same metallic material. For example, the first metal reflective layer 131 and the second metal reflective layer 132 may comprise Al. Alternatively, the first metal reflective layer 131 and the second metal reflective layer 132 may comprise Cu. The first metal reflective layer 131 and the second metal reflective layer 132 may comprise different metallic materials. For example, the first metal reflective layer 131 may comprise Cu, and the second metal reflective layer 132 may comprise Au. However, this is merely an example.

[0093] The first metal reflective layer 131 and the second metal reflective layer 132 may have a thickness of tens of nanometers; however, this disclosure is not limited thereto. For example, each of the first metal reflective layer 131 and the second metal reflective layer 132 may have a thickness of about 10 nm to about 80 nm.

[0094] Each of the first cavity 141, the second cavity 142, and the third cavity 143 can have a multi-mode cavity structure with multiple center wavelengths. Therefore, to achieve the multi-mode cavity structure, each of the first cavity 141, the second cavity 142, and the third cavity 143 can be formed with a thickness greater than or equal to a specific thickness. The first cavity 141, the second cavity 142, and the third cavity 143 can have the same thickness. The first cavity 141, the second cavity 142, and the third cavity 143 can have different effective refractive indices, resulting in different center wavelengths.

[0095] The first cavity 141, the second cavity 142, and the third cavity 143 may include, for example, silicon, silicon oxide, silicon nitride, hafnium oxide, or titanium oxide; however, this is merely an example, and the first cavity 141, the second cavity 142, and the third cavity 143 may include various other dielectric materials.

[0096] The first cavity 141 may include a substrate 140a. Furthermore, the first cavity 141 may include at least one first pattern 141a disposed in the substrate 140a in a specific shape and comprising a dielectric material different from the material of the substrate 140a. The effective refractive index of the first cavity 141 may be determined based on the material of the substrate 140a, the material of the first pattern 141a, the content of the material in the first pattern 141a, etc.

[0097] For example, the substrate 140a of the first cavity 141 may include titanium oxide. The substrate 140a of the first cavity 141 may include silicon nitride or hafnium oxide. However, this is only an example.

[0098] Specifically, in the first cavity 141, the substrate 140a may include titanium oxide, and the first pattern 141a may include silicon oxide. However, this is merely an example. The substrate 140a may include silicon oxide, and the first pattern 141a may include titanium oxide.

[0099] The first cavity 141 may have a thickness greater than or equal to a certain thickness to make it multimodal. For example, the first cavity 141 may have a thickness greater than or equal to about 200 nm and less than or equal to about 1000 nm. For example, the first cavity 141 may have a thickness greater than or equal to about 250 nm and less than or equal to about 700 nm. However, this disclosure is not limited thereto.

[0100] The second cavity 142 may include a substrate 140a and at least one second pattern 142a disposed in the substrate 140a in a specific shape. The second cavity 142 may have an effective refractive index different from that of the first cavity 141, such that the second cavity 142 has a center wavelength different from that of the first cavity 141. The effective refractive index of the second cavity 142 may be determined based on the material of the substrate 140a, the material of the second pattern 142a, the content of the material in the second pattern 142a, etc. The second pattern 142a may include the same material as the first pattern 141a. In this case, the content of the material in the second pattern 142a may be different from the content of the material in the first pattern 141a. The second pattern 142a may include a material different from that in the first pattern 141a. Similar to the first cavity 141, the second cavity 142 may have a thickness greater than or equal to a specific thickness to make it multi-mode.

[0101] The third cavity 143 may include a substrate 140a and at least one third pattern 143a disposed in the substrate 140a in a specific shape. The third cavity 143 may have an effective refractive index different from that of the first cavity 141 and the second cavity 142, such that the third cavity 143 has a center wavelength different from that of the first cavity 141 and the second cavity 142. The effective refractive index of the third cavity 143 may be determined based on the material of the substrate 140a, the material of the third pattern 143a, the content of the material in the third pattern 143a, etc. The third pattern 143a may include the same material as the first pattern 141a and the second pattern 142a. In this case, the content of the material in the third pattern 143a may be different from the content of the material in the first pattern 141a and the second pattern 142a. The third pattern 143a may include a material different from the material in the first pattern 141a and the second pattern 142a.

[0102] Similar to the first cavity 141 and the second cavity 142, the third cavity 143 may have a thickness greater than or equal to a certain thickness to make it multimodal. The first cavity 141, the second cavity 142, and the third cavity 143 may have the same thickness. For example, the first cavity 141, the second cavity 142, and the third cavity 143 may have a thickness greater than or equal to about 200 nm and less than or equal to about 1000 nm (e.g., about greater than or equal to 250 nm and less than or equal to 700 nm).

[0103] Figures 6A to 6C Examples of transmission spectra of the first cavity 141, the second cavity 142, and the third cavity 143 are shown. Figures 6A to 6C The illustration shows a case where each of the first cavity 141, the second cavity 142, and the third cavity 143 has three center wavelengths. However, this disclosure is not limited thereto, and each of the first cavity 141, the second cavity 142, and the third cavity 143 may have two or more four center wavelengths based on their thickness and effective refractive index.

[0104] Figure 6A The transmission spectrum of the first cavity 141 is shown, and the first cavity 141 may have a first wavelength λ1, a second wavelength λ2, and a third wavelength λ3 as center wavelengths. Here, each of the first wavelength λ1, the second wavelength λ2, and the third wavelength λ3 may be in the first wavelength region, the second wavelength region, and the third wavelength region, respectively.

[0105] Figure 6B The transmission spectrum of the second cavity 142 is shown, and the second cavity 142 may have a first wavelength λ1', a second wavelength λ2', and a third wavelength λ3' as center wavelengths. Each of the first wavelength λ1', the second wavelength λ2', and the third wavelength λ3' may be spaced apart from the first wavelength λ1, the second wavelength λ2, and the third wavelength λ3 by a specific distance, respectively; however, this disclosure is not limited thereto. Each of the first wavelength λ1', the second wavelength λ2', and the third wavelength λ3' may be in a first wavelength region, a second wavelength region, and a third wavelength region, respectively.

[0106] Figure 6C The transmission spectrum of the third cavity 143 is shown, and the third cavity 143 may have a first wavelength λ1”, a second wavelength λ2”, and a third wavelength λ3” as center wavelengths. Each of the first wavelength λ1”, the second wavelength λ2”, and the third wavelength λ3” may be spaced apart from the first wavelength λ1’, the second wavelength λ2’, and the third wavelength λ3’ by a specific distance; however, this disclosure is not limited thereto. Each of the first wavelength λ1”, the second wavelength λ2”, and the third wavelength λ3” may be in the first wavelength region, the second wavelength region, and the third wavelength region, respectively.

[0107] like Figures 6A to 6C As shown, each of the first cavity 141, the second cavity 142, and the third cavity 143 can realize multi-mode with multiple center wavelengths, and since the first cavity 141, the second cavity 142, and the third cavity 143 have different effective refractive indices, the first cavity 141, the second cavity 142, and the third cavity 143 can have different center wavelengths.

[0108] As mentioned above, in Figure 2 In the spectral filter 1100, when light from the first wavelength region, the second wavelength region, and the third wavelength region is incident on the bandpass filter 150, the light from the first wavelength region with wavelengths λ1, λ1', and λ1” can pass through the first band filter 151. The light from the second wavelength region with wavelengths λ2, λ2', and λ2” can pass through the second band filter 152, and the light from the third wavelength region with wavelengths λ3, λ3', and λ3” can pass through the third band filter 153.

[0109] When light of wavelengths λ1, λ1', and λ1" that have passed through the first frequency band filter 151 is incident into the first cavity 141, only light of wavelength λ1 can pass through the first cavity 141 and be incident on the first pixel 101. When light of wavelengths λ2, λ2', and λ2" that have passed through the second frequency band filter 152 is incident into the second cavity 142, only light of wavelength λ2 can be output through the second cavity 142 and be incident on the second pixel 102. When light of wavelengths λ3, λ3', and λ3" that have passed through the third frequency band filter 153 is incident into the third cavity 143, only light of wavelength λ3 can be output through the third cavity 143 and be incident on the third pixel 103. Therefore, each pixel in the first pixel 101, second pixel 102, and third pixel 103 can detect light of wavelengths λ1, λ2, and λ3.

[0110] According to an embodiment, a spectral filter 1100 capable of detecting light of a desired wavelength can be realized by combining a bandpass filter 150 that transmits light in a specific wavelength region with each of the first cavity 141, the second cavity 142, and the third cavity 143 having a multimode structure with multiple center wavelengths. Furthermore, by forming the first cavity 141, the second cavity 142, and the third cavity 143 with the same thickness, the spectral filter 1100 can be manufactured using a simpler process.

[0111] Figure 7This is a diagram of a spectral filter 1200 according to another example embodiment. Figure 7 An example is shown where light from the first to the fourth wavelength regions is incident on a spectral filter 1200. Here, the first wavelength region may include a first wavelength λ1, a first wavelength λ1', and a first wavelength λ1'", the second wavelength region may include a second wavelength λ2, a second wavelength λ2', and a second wavelength λ2", the third wavelength region may include a third wavelength λ3, a third wavelength λ3', and a third wavelength λ3'", and the fourth wavelength region may include a fourth wavelength λ4, a fourth wavelength λ4', and a fourth wavelength λ4'". Hereinafter, embodiments will be described focusing on differences from the embodiments described above.

[0112] refer to Figure 7 The spectral filter 1200 may include multiple filters (i.e., first filter 211, second filter 212, third filter 213, fourth filter 214, fifth filter 215, sixth filter 216, seventh filter 217, and eighth filter 218), and a pixel array 4100 including multiple pixels (i.e., first pixel 101, second pixel 102, third pixel 103, fourth pixel 104, fifth pixel 105, sixth pixel 106, seventh pixel 107, and eighth pixel 108) may be disposed below the spectral filter 1200. Figure 7 Eight filters (i.e., first filters 211 to eighth filters 218) and eight pixels (i.e., first pixel 101 to eighth pixel 108) are shown.

[0113] The first filter 211 and the second filter 212 may have a center wavelength in a first wavelength region. The first wavelength region may be in the range of, for example, about 350 nm to about 500 nm. The third filter 213 and the fourth filter 214 may have a center wavelength in a second wavelength region. The second wavelength region may be in the range of, for example, about 500 nm to about 650 nm.

[0114] The fifth filter 215 and the sixth filter 216 may have a center wavelength in the third wavelength region. The third wavelength region may be in the range of, for example, about 650 nm to about 800 nm. The seventh filter 217 and the eighth filter 218 may have a center wavelength in the fourth wavelength region. The fourth wavelength region may be in the range of, for example, about 800 nm to about 1000 nm or about 800 nm to about 1500 nm.

[0115] The first filters 211 to the eighth filters 218 may include a resonator 260 and a bandpass filter 250 disposed above the resonator 260. The resonator 260 may include a first cavity 261, a second cavity 262, a third cavity 263, a fourth cavity 264, a fifth cavity 265, a sixth cavity 266, a seventh cavity 267, and an eighth cavity 268 disposed between the first metal reflective layer 231 and the second metal reflective layer 232. The bandpass filter 250 may include a first band filter 251, a second band filter 252, a third band filter 253, and a fourth band filter 254. A lower dielectric layer 270 may also be disposed between the resonator 260 and the pixel array 4100, and an upper dielectric layer 280 may also be disposed between the resonator 260 and the bandpass filter 250.

[0116] Each of the first cavities 261 to the eighth cavities 268 may have a multi-mode structure with multiple center wavelengths as described above. For this purpose, each of the first cavities 261 to the eighth cavities 268 may have a thickness greater than or equal to a specific thickness. Furthermore, the first cavities 261 to the eighth cavities 268 may have different effective refractive indices, such that they have different center wavelengths.

[0117] As described above, the color filter of the broadband filter can be used as a bandpass filter 250. Each of the first band filters 251 to the fourth band filters 254 can transmit light in a specific wavelength range and block light in other wavelength ranges.

[0118] The first frequency band filter 251 can transmit light in a first wavelength region (e.g., about 350 nm to about 500 nm). The first frequency band filter 251 can correspond to the first cavity 261 and the second cavity 262. The first frequency band filter 251 can be disposed above the first cavity 261 and the second cavity 262. The second frequency band filter 252 can transmit light in a second wavelength region (e.g., about 500 nm to about 650 nm). The second frequency band filter 252 can correspond to the third cavity 263 and the fourth cavity 264. The second frequency band filter 252 can be disposed above the third cavity 263 and the fourth cavity 264.

[0119] The third-band filter 253 can transmit light in a third wavelength region (e.g., about 650 nm to about 800 nm). The third-band filter 253 can correspond to the fifth cavity 265 and the sixth cavity 266. The third-band filter 253 can be disposed above the fifth cavity 265 and the sixth cavity 266.

[0120] The fourth-band filter 254 can transmit light in a fourth wavelength region (e.g., about 800 nm to about 1000 nm). The fourth-band filter 254 can correspond to the seventh cavity 267 and the eighth cavity 268. The fourth-band filter 254 can be positioned above the seventh cavity 267 and the eighth cavity 268.

[0121] For example, blue, green, and red filters can be used as the first band filter 251, the second band filter 252, and the third band filter 253, respectively, and a near-field ray (NIR) filter can be used as the fourth band filter. When the fourth wavelength region has a range of NIR wavelengths, a blue filter can be used as the fourth band filter 254.

[0122] exist Figure 7 In the spectral filter 1200, when light from the first wavelength region, the second wavelength region, the third wavelength region, and the fourth wavelength region is incident on the bandpass filter 250, the light with the first wavelength λ1, the light with the first wavelength λ1', and the light with the first wavelength λ1" in the first wavelength region can pass through the first frequency band filter 251 and be incident on the first cavity 261 and the second cavity 262. Here, the light with the first wavelength λ1 can be output through the first cavity 261 and incident on the first pixel 101, and the light with the first wavelength λ1' can be output through the second cavity 262 and incident on the second pixel 102.

[0123] Light of the second wavelength λ2, the second wavelength λ2', and the second wavelength λ2" in the second wavelength region can pass through the second frequency band filter 252 and be incident on the third cavity 263 and the fourth cavity 264. Here, light of the second wavelength λ2 can be output through the third cavity 263 to be incident on the third pixel 103, and light of the second wavelength λ2' can be output through the fourth cavity 264 to be incident on the fourth pixel 104.

[0124] Light of the third wavelength λ3, the third wavelength λ3', and the third wavelength λ3” in the third wavelength region can pass through the third band filter 253 and be incident on the fifth cavity 265 and the sixth cavity 266. Here, the light of the third wavelength λ3 can be output through the fifth cavity 265 and incident on the fifth pixel 105, and the light of the third wavelength λ3' can be output through the sixth cavity 266 and incident on the sixth pixel 106.

[0125] Light of wavelength λ4, wavelength λ4', and wavelength λ4'” in the fourth wavelength region can pass through the fourth band filter 254 and be incident on the seventh cavity 267 and the eighth cavity 268. Here, light of wavelength λ4 can be output through the seventh cavity 267 and incident on the seventh pixel 107, and light of wavelength λ4' can be output through the eighth cavity 268 and incident on the eighth pixel 108.

[0126] The following text will describe about Figure 7 Simulation results for the spectral filter 1200. A Cu layer with a thickness of 30 nm and an Al layer with a thickness of 10 nm are used as the first metal reflective layer 231 and the second metal reflective layer 232, respectively. The first cavity 261 to the eighth cavity 268 have a thickness of 400 nm.

[0127] Figure 8A and Figure 8B It shows Figure 7 Simulation results of the transmission spectra of the first cavity 261 and the second cavity 262 in the spectral filter 1200. Here, the first cavity 261 consists only of titanium oxide, while the substrate of the second cavity 262 consists of titanium oxide, and the pattern of the second cavity 262 consists of silicon oxide. The pattern content in the second cavity 262 is 20%.

[0128] refer to Figure 8A and Figure 8B Each of the first cavity 261 and the second cavity 262 has two center wavelengths (i.e., the first cavity 261 has two center wavelengths, one for the blue light region and one for the red light region; and the second cavity 262 has two center wavelengths, one for the blue light region and one for the red light region). Furthermore, the center wavelength of the second cavity 262 is offset from the center wavelength of the first cavity 261 by a specific distance.

[0129] Figure 9A It shows the way Figure 7 The simulation results of the absorption spectra detected in the first pixel 101 and the second pixel 102 by the spectral filter 1200. Here, the blue filter is used as the first frequency band filter 251. Reference Figure 9A The wavelength of the blue light region is detected in the first pixel 101 and the second pixel 102.

[0130] Figure 9B It shows the way Figure 7 Simulation results of the absorption spectra detected by the spectral filter 1200 in the third pixel 103 and the fourth pixel 104. Here, the green filter is used as the second frequency band filter 252. Reference Figure 9B The wavelength of the green light region is detected in the third pixel 103 and the fourth pixel 104.

[0131] Figure 9C It shows the way Figure 7 Simulation results of the absorption spectra detected by the spectral filter 1200 in the fifth pixel 105 and the sixth pixel 106. Here, the red filter is used as the third frequency band filter 253. Reference Figure 9C The wavelength of the red light region is detected in the fifth pixel 105 and the sixth pixel 106.

[0132] Figure 9D It shows the way Figure 7 Simulation results of the absorption spectra detected by the spectral filter 1200 in the seventh pixel 107 and the eighth pixel 108. Here, the blue filter is used as the fourth band filter 254. Reference Figure 9D The wavelength of the NIR light region is detected in the seventh pixel 107 and the eighth pixel 108.

[0133] As described above, according to the embodiments, a spectral filter 1200 with broadband characteristics ranging from, for example, ultraviolet to NIR can be implemented. The foregoing embodiments describe a bandpass filter 250 comprising four frequency band filters (i.e., first band filters 251 to fourth band filters 254); however, this disclosure is not limited thereto, and the bandpass filter 250 may comprise a variety of numbers of frequency band filters. Furthermore, although the foregoing embodiments describe each of the first band filters 251 to fourth band filters 254 comprising two cavities, this disclosure is not limited thereto, and the number of cavities corresponding to each of the first band filters 251 to fourth band filters 254 may vary.

[0134] Figure 10 This is a diagram of a spectral filter 1300 according to another example embodiment.

[0135] refer to Figure 10 The spectral filter 1300 may include multiple filters (i.e., a first filter 311, a second filter 312, and a third filter 313), and a pixel array 4100 including multiple pixels (i.e., a first pixel 101, a second pixel 102, and a third pixel 103) may be disposed below the spectral filter 1300. Figure 10 Examples of three filters are shown, namely, the first filter 311, the second filter 312, and the third filter 313.

[0136] The first filter 311, the second filter 312, and the third filter 313 may include a resonator 340 and a bandpass filter 350 disposed above the resonator 340. The resonator 340 may include a first cavity 341, a second cavity 342, and a third cavity 343 disposed between a first metallic reflective layer 331 and a second metallic reflective layer 332. The bandpass filter 350 may include a first band filter 351, a second band filter 352, and a third band filter 353. Since the resonator 340 and the bandpass filter 350 have been described above, any redundant descriptions thereof are omitted.

[0137] A lower dielectric layer 370 may also be disposed between the resonator 340 and the pixel array 4100, and an upper dielectric layer 380 may also be disposed between the resonator 340 and the bandpass filter 350. The lower dielectric layer 370 and the upper dielectric layer 380 can improve the transmittance of the spectral filter 1300. The lower dielectric layer 370 and the upper dielectric layer 380 may include, for example, titanium oxide, silicon nitride, hafnium oxide, silicon oxide, high refractive index polymers, etc.; however, the foregoing is provided only as an example.

[0138] The first dielectric layer 371 and the second dielectric layer 381 can be disposed below and above the first cavity 341, respectively. The first dielectric layer 371 and the second dielectric layer 381 can improve the transmittance of the first filter 311. For example, the first dielectric layer 371 and the second dielectric layer 381 can improve the transmittance in the first wavelength region.

[0139] Each dielectric layer in the first dielectric layer 371 and the second dielectric layer 381 may include a dielectric material with a different refractive index. Specifically, the first dielectric layer 371 may include a substrate 370a and at least one first pattern 371a disposed in the substrate 370a in a specific shape, and the second dielectric layer 381 may include a substrate 380a and at least one first pattern 381a disposed in the substrate 380a in a specific shape. The effective refractive index of each dielectric layer in the first dielectric layer 371 and the second dielectric layer 381 may be determined based on the materials of the substrates 370a and 380a, the materials of the first patterns 371a and 381a, the content of the materials of the first patterns 371a and 381a, etc.

[0140] The third dielectric layer 372 and the fourth dielectric layer 382 may be disposed below and above the second cavity 342, respectively. The third dielectric layer 372 and the fourth dielectric layer 382 may improve the transmittance of the second filter 312. For example, the third dielectric layer 372 and the fourth dielectric layer 382 may improve the transmittance in the second wavelength region. The third dielectric layer 372 and the fourth dielectric layer 382 may have an effective refractive index different from the effective refractive index of the first dielectric layer 371 and the second dielectric layer 381. The third dielectric layer 372 may include a substrate 370a and at least one second pattern 372a disposed in the substrate 370a in a specific shape, and the fourth dielectric layer 382 may include a substrate 380a and at least one second pattern 382a disposed in the substrate 380a in a specific shape. The effective refractive index of each dielectric layer in the third dielectric layer 372 and the fourth dielectric layer 382 can be determined based on the materials of the substrates 370a and 380a, the materials of the second patterns 372a and 382a, and the content of the materials of the second patterns 372a and 382a.

[0141] The fifth dielectric layer 373 and the sixth dielectric layer 383 may be disposed below and above the third cavity 343, respectively. The fifth dielectric layer 373 and the sixth dielectric layer 383 can improve the transmittance of the third filter 313. For example, the fifth dielectric layer 373 and the sixth dielectric layer 383 can improve the transmittance in the third wavelength region. The fifth dielectric layer 373 and the sixth dielectric layer 383 may have an effective refractive index different from the effective refractive indices of the first dielectric layer 371, the second dielectric layer 381, the third dielectric layer 372, and the fourth dielectric layer 382. The fifth dielectric layer 373 may include a substrate 370a and at least one third pattern 373a disposed in the substrate 370a in a specific shape, and the sixth dielectric layer 383 may include a substrate 380a and at least one third pattern 383a disposed in the substrate 380a in a specific shape. The effective refractive index of each dielectric layer in the fifth dielectric layer 373 and the sixth dielectric layer 383 can be determined based on the materials of the substrates 370a and 380a, the materials of the third patterns 373a and 383a, and the content of the materials of the third patterns 373a and 383a.

[0142] Figure 11 This is a diagram of a spectral filter 1400 according to another example embodiment. Besides the bandpass filter 450 disposed below the resonator 440, Figure 11 The spectral filter 1400 can be used with Figure 2 The spectral filter is the same as that of 1100.

[0143] refer to Figure 11The spectral filter 1400 may include multiple filters (i.e., a first filter 411, a second filter 412, and a third filter 413), and a pixel array 4100 including multiple pixels (i.e., a first pixel 101, a second pixel 102, and a third pixel 103) may be disposed below the spectral filter 1400.

[0144] The first filter 411, the second filter 412, and the third filter 413 may include a resonator 440 and a bandpass filter 450 disposed below the resonator 440. The resonator 440 may include a first cavity 441, a second cavity 442, and a third cavity 443 disposed between a first metallic reflective layer 431 and a second metallic reflective layer 432. The bandpass filter 450 may include a first band filter 451, a second band filter 452, and a third band filter 453. Since the resonator 440 and the bandpass filter 450 have been described above, any redundant descriptions thereof are omitted.

[0145] A lower dielectric layer 470 can be disposed below the resonator 440, and an upper dielectric layer 480 can be disposed above the resonator 440. The lower dielectric layer 470 and the upper dielectric layer 480 may include... Figure 10 The lower dielectric layer 370 and the upper dielectric layer 380 are used to improve the transmittance of the spectral filter 1300.

[0146] Figure 12 This is a schematic block diagram of an image sensor 1000 according to an example embodiment.

[0147] refer to Figure 12The image sensor 1000 may include a spectral filter 9100, a pixel array 4100, a timing controller 4010, a row decoder 4020, and an output circuit 4030. The spectral filter 9100 may include multiple filters that transmit light in different wavelength regions and are arranged in a 2D manner. The pixel array 4100 may include multiple pixels that detect light of different wavelengths transmitted through the multiple filters. Specifically, the pixel array 4100 may include pixels arranged in a 2D manner along multiple rows and columns. The row decoder 4020 may select 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 may output a light detection signal from the pixels arranged along the selected row, column by column. For this purpose, the output circuit 4030 may include a column decoder and an analog-to-digital converter (ADC). For example, the output circuit 4030 may include multiple ADCs arranged for each column between the column decoder and the pixel array 4100, or a single ADC located at the output of the column decoder. The timing controller 4010, line decoder 4020, and output circuit 4030 can be implemented as a single chip or separate chips. A processor for processing the image signal output through the output circuit 4030 can be implemented as a single chip containing the timing controller 4010, line decoder 4020, and output circuit 4030. The pixel array 4100 can include multiple pixels that detect light of different wavelengths, and the pixels can be arranged in various ways.

[0148] Figure 13 It can be applied to Figure 12 A plan view of an example of the spectral filter 9100 of the image sensor 1100.

[0149] refer to Figure 13 The spectral filter 9100 may include multiple filter groups 9110 arranged in a 2D manner. Each filter group 9110 may include sixteen filters arranged in a 4×4 array (i.e., first filter F1, second filter F2, third filter F3, fourth filter F4, fifth filter F5, sixth filter F6, seventh filter F7, eighth filter F8, ninth filter F9, tenth filter F10, eleventh filter F11, twelfth filter F12, thirteenth filter F13, fourteenth filter F14, fifteenth filter F15 and sixteenth filter F16).

[0150] The first filter F1 and the second filter F2 can have center wavelengths UV1 and UV2 in the ultraviolet region, and the third filter F3 to the fifth filter F5 can have center wavelengths B1 to B3 in the blue light region. The sixth filter F6 to the eleventh filter F11 can have center wavelengths G1 to G6 in the green light region, and the twelfth filter F12 to the fourteenth filter F14 can have center wavelengths R1 to R3 in the red light region. The fifteenth filter F15 and the sixteenth filter F16 can have center wavelengths NIR1 and NIR2 in the NIR region.

[0151] Figure 14 It can be applied to Figure 12 A plan view of another example of the spectral filter 9100 for the image sensor. For ease of illustration, Figure 14 This is a planar diagram of a 9120 filter bank.

[0152] refer to Figure 14 Each filter bank 9120 may include nine filters arranged in a 3×3 array (i.e., first filter F1 to ninth filter F9). First filter F1 and second filter F2 may have center wavelengths UV1 and UV2 in the ultraviolet region, and fourth filter F4, fifth filter F5, and seventh filter F7 may have center wavelengths B1 to B3 in the blue light region. Third filter F3 and sixth filter F6 may have center wavelengths G1 and G2 in the green light region, and eighth filter F8 and ninth filter F9 may have center wavelengths R1 and R2 in the red light region.

[0153] Figure 15 It can be applied to Figure 12 A plan view of another example of the spectral filter 9100 for the image sensor. For ease of illustration, Figure 15 This is a plan view of a 9130 filter bank.

[0154] refer to Figure 15Each filter bank 9130 may include twenty-five filters arranged in a 5×5 array (i.e., filters F1 through F16, F17, F18, F19, F20, F21, F22, F23, F24, and F25). Filters F1 through F3 may have center wavelengths UV1 through UV3 in the ultraviolet region, and filters F6, F7, F8, F11, and F12 may have center wavelengths B1 through B5 in the blue light region. Filters F4, F5, and F9 may have center wavelengths G1 through G3 in the green light region, and filters F10, F13, F14, F15, F18, and F19 may have center wavelengths R1 through R6 in the red light region. The twentieth filter F20, the twenty-third filter F23, the twenty-fourth filter F24, and the twenty-fifth filter F25 can have center wavelengths NIR1 to NIR4 in the NIR region.

[0155] The image sensor 1000 with the aforementioned spectral filter can be employed by a variety of high-performance optical devices or high-performance electronic devices. Electronic devices may include, for example, smartphones, mobile phones, cellular 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, but this disclosure is not limited thereto.

[0156] In addition to the image sensor 1000, the electronic device may also include a processor for controlling the image sensor, such as an application processor (AP). The processor drives an operating system or application to control multiple hardware or software components and perform various data processing and calculations. The processor may also include a graphics processing unit (GPU) and / or an image signal processor. When the processor includes an image signal processor, it can be used to store and / or output images (or videos) acquired by the image sensor.

[0157] Figure 16 This is a schematic block diagram of an electronic device ED01 including an image sensor 1000. (Reference) Figure 16In the network environment ED00, electronic device ED01 can communicate with another electronic device ED02 via a first network ED98 (e.g., a short-range wireless communication network), or with another electronic device ED04 and / or server ED08 via a second network ED99 (e.g., a long-range wireless communication network). Electronic device ED01 can communicate with electronic device ED04 via server ED08. Electronic device ED01 may include 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 identification module ED96, and / or an antenna module ED97. In electronic device ED01, some components (e.g., display device ED60, etc.) may be omitted, or other components may be added. Some of the components may be implemented as an integrated circuit. For example, the sensor module ED76 (e.g., a fingerprint sensor, an iris sensor, an illuminance sensor, etc.) can be implemented by embedding it in the display device ED60 (e.g., a display, etc.). Furthermore, when the image sensor 1000 includes spectral functionality, some functions of the sensor module ED76 (e.g., a color sensor and an illuminance sensor) can be implemented by the image sensor 1000 instead of a separate sensor module.

[0158] Processor ED20 can control one or more other components (e.g., hardware and software components) of electronic device ED01 connected to processor ED20 by executing software (e.g., program ED40, etc.) and perform various data processing or calculations. As part of the data processing or calculation, processor ED20 can load commands and / or data received from other components (e.g., sensor module ED76, communication module ED90, etc.) into volatile memory ED32, process the commands and / or data stored in volatile memory ED32, and store the result data in non-volatile memory ED34. Processor ED20 may include a main processor ED21 (e.g., central processing unit, application processor, etc.) and an auxiliary processor ED23 (e.g., graphics processing unit, image signal processor, sensor hub processor, communication processor, etc.) that can operate independently of or with the main processor ED21. Auxiliary processor ED23 may use less power than main processor ED21 and can perform specialized functions.

[0159] The auxiliary processor ED23 can replace the main processor ED21 when the main processor ED21 is inactive (i.e., in sleep mode), or, when the main processor ED21 is active (i.e., in application execution mode), work with the main processor ED21 to control the functions and / or states of some components of the electronic device ED01 (e.g., display device ED60, sensor module ED76, communication module ED90, etc.). The auxiliary processor ED23 (e.g., image signal processor, communication processor, etc.) can be implemented as part of other functionally related components (e.g., camera module ED80, communication module ED90, etc.).

[0160] Memory ED30 can store various data required by the components of electronic device ED01 (e.g., processor ED20, sensor module ED76, etc.). This data may include, for example, software (e.g., program ED40, etc.) and input and / or output data regarding commands associated with it. Memory ED30 may include volatile memory ED32 and / or non-volatile memory ED34. Non-volatile memory ED34 may include internal memory ED36 fixedly installed in electronic device ED01 and removable external memory ED38.

[0161] The program ED40 can be stored as software in the memory ED30, and the program ED40 may include the operating system ED42, middleware ED44 and / or application ED46.

[0162] Input device ED50 can receive commands and / or data from outside electronic device ED01 (e.g., from a user) to be used by components of electronic device ED01 (e.g., processor ED20, etc.). Input device ED50 may include a microphone, mouse, keyboard, and / or digital pen (e.g., stylus, etc.).

[0163] Audio output device ED55 can output audio signals to the external device ED01. Audio output device ED55 may include a speaker and / or a handset. The speaker can be used for general purposes such as multimedia playback or recording playback, and the handset can be used to receive incoming calls. The handset can be implemented by being coupled as part of the speaker, or it can be implemented as a separate, independent device.

[0164] Display device ED60 can visually provide information to the outside of electronic device ED01. Display device ED60 may include a display, holographic device or projector, and control circuitry for controlling the corresponding device. Display device ED60 may include touch circuitry configured to detect touch and / or sensor circuitry configured to measure the intensity of the force generated by the touch (e.g., pressure sensor, etc.).

[0165] The audio module ED70 can convert sound into electrical signals or vice versa. The audio module ED70 can obtain sound through the input device ED50, or output sound through the speakers and / or headphones of another electronic device (e.g., electronic device ED02, etc.) connected to the audio output device ED55 and / or electronic device ED01 via wired or wireless means.

[0166] Sensor module ED76 can detect the operating status (e.g., power, temperature, etc.) or external environmental status (e.g., user status, etc.) of electronic device ED01, and can generate electrical signals and / or data values ​​corresponding to the detected status. Sensor module ED76 may include gesture sensors, gyroscope sensors, atmospheric pressure sensors, magnetic sensors, accelerometers, grip sensors, proximity sensors, color sensors, infrared (IR) sensors, biometric sensors, temperature sensors, humidity sensors, and / or illuminance sensors.

[0167] Interface ED77 can support one or more specified protocols for electronic device ED01 to connect to another electronic device (e.g., electronic device ED02, etc.) via wired or wireless means. 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.

[0168] The connection terminal ED78 may include a connector for physically connecting electronic device ED01 to another electronic device (e.g., electronic device ED02, etc.). The connection terminal ED78 may include an HDMI connector, a USB connector, an SD card connector, and / or an audio connector (e.g., a headphone connector, etc.).

[0169] The haptic module ED79 can convert electrical signals into mechanical stimuli (e.g., vibration, movement, etc.) or electrical stimuli that can be perceived by the user through touch or motion. The haptic module ED79 may include a motor, a piezoelectric device, and / or an electrical stimulation device.

[0170] The ED80 camera module can capture still images and video. The ED80 camera module may include a lens assembly, which includes one or more lenses. Figure 1 The camera module ED80 includes an image sensor 1000, an image signal processor, and / or a flash. The lens assembly within the camera module collects light emitted from the subject for image capture.

[0171] The power management module ED88 manages the power supplied to the electronic device ED01. The power management module ED88 can be implemented as part of a power management integrated circuit (PMIC).

[0172] Battery ED89 can supply power to the components of electronic device ED01. Battery ED89 may include non-rechargeable primary batteries, rechargeable secondary batteries, and / or fuel cells.

[0173] Communication module ED90 can establish a direct (wired) communication channel and / or a wireless communication channel between electronic device ED01 and another electronic device (e.g., electronic device ED02, electronic device ED04, or server ED08, etc.), and can support communication through the established communication channel. Communication module ED90 can operate independently of processor ED20 (e.g., application processor, etc.) and can include one or more communication processors supporting wired and / or wireless communication. Communication module ED90 may include wireless communication module ED92 (e.g., cellular communication module, short-range wireless communication module, Global Navigation Satellite System (GNSS) communication module, etc.) and / or wired communication module ED94 (e.g., local area network (LAN) communication module, power line communication module, etc.). Among the above communication modules, the corresponding communication module can communicate with another electronic device through a first network ED98 (e.g., a short-range communication network such as Bluetooth, Wi-Fi Direct, or Infrared Data Association (IrDA)) or a second network ED99 (e.g., a long-range communication network such as a cellular network, the Internet, or a computer network (LAN, WAN, etc.). These various types of communication modules can be integrated into a single component (e.g., a single chip, etc.) or implemented as multiple separate components (e.g., multiple chips). The wireless communication module ED92 can verify and authenticate the electronic device ED01 within a communication network (e.g., the first network ED98 and / or the second network ED99) by using subscriber information (e.g., the International Mobile Subscriber Identifier (IMSI) etc.) stored in the subscriber identification module ED96.

[0174] Antenna module ED97 can transmit signals and / or power to or from an external source (e.g., another electronic device). The antenna may include a transmitter formed in a conductive pattern on a substrate (e.g., a printed circuit board (PCB)). Antenna module ED97 may include one or more antennas. When antenna module ED97 includes multiple antennas, communication module ED90 can select an antenna suitable for a communication method used in a communication network such as a first network ED98 and / or a second network ED99. Signals and / or power can be transmitted or received between communication module ED90 and another electronic device via the selected antenna. Other components besides antennas (e.g., RFIC, etc.) may be included as part of antenna module ED97.

[0175] Some of the components can be connected to each other through communication methods between peripheral devices (e.g., bus, general purpose input and output (GPIO), serial peripheral interface (SPI), mobile industry processor interface (MIPI), etc.) and can exchange signals (e.g., commands, data, etc.).

[0176] Commands or data can be sent or received between electronic device ED01 and external electronic device ED04 via server ED08 connected to the second network ED99. Electronic devices ED02 and ED04 can be of the same or different type as electronic device ED01. All or part of the operations performed in electronic device ED01 can be performed in one or more of electronic devices ED02, ED04, and ED08. For example, when electronic device ED01 needs to perform a function or service, it can request one or more electronic devices to perform part or all of the function or service, rather than performing the function or service itself. The one or more electronic devices receiving the request can perform additional functions or services related to the request and send the results of the execution back to electronic device ED01. Cloud computing, distributed computing, and / or client-server computing technologies can be used for this purpose.

[0177] Figure 17 yes Figure 16 A schematic block diagram of the ED80 camera module. (Reference) Figure 17 The camera module ED80 may include a lens assembly CM10, a flash CM20, and an image sensor 1000 (e.g., Figure 12 The camera module ED80 may include an image sensor 1000, an image stabilizer CM40, a memory CM50 (e.g., buffer memory), and / or an image signal processor CM60. A lens assembly CM10 can collect light emitted from the subject for image capture. The camera module ED80 may include multiple lens assemblies CM10, and in this case, the camera module ED80 may be a binocular camera, a 360-degree camera, or a spherical camera. Some of the lens assemblies CM10 may have the same lens properties (e.g., angle of view, focal length, autofocus, f-number, optical zoom, etc.) or different lens properties. The lens assembly CM10 may include a wide-angle lens or a telephoto lens.

[0178] The flash CM20 can emit light to amplify light emitted or reflected from the subject. The flash CM20 may include one or more light-emitting diodes (e.g., red-green-blue (RGB) LEDs, white LEDs, infrared LEDs, ultraviolet LEDs, etc.) and / or a xenon lamp. The image sensor 1000 may include... Figure 1The image sensor 1000 converts light emitted or reflected from the subject and transmitted through the lens assembly CM10 into electrical signals, thereby obtaining an image corresponding to the subject. The image sensor 1000 may include one or more sensors selected from image sensors with different properties, such as RGB sensors, black-and-white (BW) sensors, IR sensors, or UV sensors. Each sensor included in the image sensor 1000 may be implemented as a charge-coupled device (CCD) sensor and / or a complementary metal-oxide-semiconductor (CMOS) sensor.

[0179] Image stabilizer CM40 can respond to movement of camera module ED80 or electronics ED01 including camera module ED80 by moving one or more lenses or image sensor 1000 included in lens assembly CM10 in a specific direction, or by controlling (e.g., adjusting readout timing, etc.) the movement characteristics of image sensor 1000 to compensate for negative effects caused by movement. Image stabilizer CM40 can detect movement of camera module ED80 or electronics ED01 using a gyroscope sensor (not shown) or accelerometer sensor (not shown) disposed inside or outside camera module ED80. Image stabilizer CM40 can be implemented in an optical form.

[0180] The memory CM50 can store partial or complete data of the image acquired by the image sensor 1000 for subsequent image processing operations. For example, when multiple images are acquired at high speed, only the low-resolution image is displayed, while the acquired raw data (e.g., Bayer patterned data, high-resolution data, etc.) is stored in the memory CM50. The memory CM50 can then be used to send the raw data of the selected (e.g., user-selected, etc.) image to the image signal processor CM60. The memory CM50 can be incorporated into the memory ED30 of the electronic device ED01, or configured as a separate memory operating independently.

[0181] Image signal processor CM60 can perform image processing on images acquired by image sensor 1000 or image data stored in memory CM50. Image processing may include depth map generation, 3D modeling, panorama generation, feature point extraction, image compositing, and / or image compensation (e.g., noise reduction, resolution adjustment, brightness adjustment, blurring, sharpening, softening, etc.). Image signal processor CM60 can perform control (e.g., exposure time control or readout timing control, etc.) on components included in camera module ED80 (e.g., image sensor 1000, etc.). Images processed by image signal processor CM60 may be stored again in memory CM50 for additional processing, or provided to external components of camera module ED80 (e.g., memory ED30, display device ED60, electronic device ED02, electronic device ED04, server ED08, etc.). Image signal processor CM60 may be incorporated into processor ED20, or configured as a separate processor operating independently of 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 undergo additional image processing by the processor ED20 and then be displayed by the display device ED60.

[0182] Electronic device ED01 may include multiple camera modules ED80 with different attributes or functions. In this case, one camera module of camera module ED80 may be a wide-angle camera, and another camera module may be a telephoto camera. Similarly, one camera module of camera module ED80 may be a front-facing camera, and another camera module may be a rear-facing camera.

[0183] The image sensor 1000 according to the embodiment can be applied to Figure 18 The mobile phone or smartphone 5100m shown in (a) Figure 18 The tablet computer or smart tablet computer 5200 shown in (b) Figure 18 The digital camera or camcorder 5300 shown in (c) Figure 18 The notebook computer 5400 shown in (d) Figure 18 The television or smart TV 5500 shown in (e) is an example. For instance, a smartphone 5100m or a smart tablet 5200 may include multiple high-resolution cameras, each with a high-resolution image sensor mounted thereon. By using high-resolution cameras, depth information of the subject in the image can be extracted, the image can be adjusted for defocusing, or the subject in the image can be automatically identified.

[0184] Furthermore, the image sensor 1000 can be applied to Figure 19 The smart refrigerator 5600 shown in (a) Figure 19 The security camera 5700 shown in (b) Figure 19 Robot 5800 shown in (c) Figure 19 Examples include the medical camera 5900 shown in (d). For instance, the smart refrigerator 5600 can automatically identify food in the refrigerator using an image sensor and notify the user of the presence of specific food, the type of food input or output, etc., via a smartphone. The security camera 5700 can provide ultra-high resolution images and can identify objects or people in images in dark environments using high sensitivity. The robot 5800 can be placed in disaster or industrial sites where people cannot directly access it and can provide high-resolution images. The medical camera 5900 can provide high-resolution images for diagnosis or surgery and can therefore dynamically adjust the field of view.

[0185] Furthermore, the image sensor 1000 can be applied to Figure 19 The vehicle 6000 is shown in (e). The vehicle 6000 may include a plurality of vehicle cameras 6010, 6020, 6030, and 6040 disposed at different locations. Each of the vehicle cameras 6010, 6020, 6030, and 6040 may include an image sensor according to an embodiment. The vehicle 6000 can provide the driver with various information about the interior or periphery of the vehicle 6000 by using the vehicle cameras 6010, 6020, 6030, and 6040, and thus can automatically identify objects or people in the images and provide the information required for autonomous driving.

[0186] According to an example embodiment, by combining a multimode cavity with multiple center wavelengths with a bandpass filter that transmits light only in a specific wavelength region, a broadband spectral filter capable of detecting light of a desired wavelength can be realized. Furthermore, by forming the multimode cavity with the same thickness, the spectral filter can be fabricated using a simpler process. According to another example embodiment, an image sensor including the aforementioned spectral filter and an electronic device including the image sensor can be provided.

[0187] It should be understood that the embodiments described herein should be considered in a descriptive sense and not for limiting purposes only. The description of features or aspects in each embodiment should generally be considered as applicable to other similar features or aspects in other embodiments. Although one or more embodiments have been described with reference to the accompanying drawings, those skilled in the art will understand that various changes in form and detail may be made without departing from the spirit and scope defined by the appended claims.

Claims

1. A spectral filter, comprising: Resonators, including: - First metallic reflective layer; - A second metallic reflective layer, disposed above the first metallic reflective layer; and - Multiple cavities are disposed between the first metal reflective layer and the second metal reflective layer; and A bandpass filter is disposed below the first metal reflective layer or above the second metal reflective layer. The bandpass filter includes multiple frequency band filters that transmit light in multiple wavelength regions. The plurality of frequency band filters are configured to correspond to the plurality of cavities. Each of the multiple frequency band filters transmits light in the corresponding wavelength region, and Each of the plurality of cavities corresponding to the plurality of frequency band filters has a plurality of center wavelengths, one of which is included in the corresponding wavelength region of the corresponding frequency band filter corresponding to the cavity, and At least one of the plurality of cavities includes a substrate and at least one pattern disposed in the substrate in a shape.

2. The spectral filter according to claim 1, wherein, The bandpass filter is a color filter or a broadband filter.

3. The spectral filter according to claim 1, wherein, Each of the multiple frequency band filters corresponds one-to-one with the multiple cavities.

4. The spectral filter according to claim 3, wherein, The plurality of frequency band filters include a first frequency band filter configured to transmit light in a first wavelength region, a second frequency band filter configured to transmit light in a second wavelength region, and a third frequency band filter configured to transmit light in a third wavelength region.

5. The spectral filter according to claim 4, wherein, The plurality of cavities includes a first cavity corresponding to the first frequency band filter, a second cavity corresponding to the second frequency band filter, and a third cavity corresponding to the third frequency band filter.

6. The spectral filter according to claim 5, wherein, The first cavity has a plurality of first center wavelengths and one of the plurality of first center wavelengths is in the first wavelength region; the second cavity has a plurality of second center wavelengths and one of the plurality of second center wavelengths is in the second wavelength region; and the third cavity has a plurality of third center wavelengths and one of the plurality of third center wavelengths is in the third wavelength region.

7. The spectral filter according to claim 5, wherein, The refractive indices of the first cavity, the second cavity, and the third cavity are different.

8. The spectral filter according to claim 7, wherein, The thickness of the first cavity, the thickness of the second cavity, and the thickness of the third cavity are the same.

9. The spectral filter according to claim 8, wherein, The thickness of the first cavity, the second cavity, and the third cavity is greater than or equal to 200 nm and less than or equal to 1000 nm.

10. The spectral filter according to claim 5, wherein, The substrate of each of the first cavity, the second cavity, and the third cavity comprises titanium oxide.

11. The spectral filter according to claim 5, wherein, The substrate of each of the first cavity, the second cavity, and the third cavity comprises silicon nitride or hafnium oxide.

12. The spectral filter according to claim 1, wherein, Each of the plurality of frequency band filters corresponds to two or more of the plurality of cavities.

13. The spectral filter according to claim 1, wherein, The first metal reflective layer comprises a first metal material, and the second metal reflective layer comprises a second metal material, wherein the first metal material and the second metal material are the same or different.

14. The spectral filter according to claim 13, wherein, The first metal reflective layer or the second metal reflective layer includes Al, Cu, Ag, Au, Ti, W or TiN.

15. The spectral filter according to claim 14, wherein, The first metal reflective layer or the second metal reflective layer further includes polycrystalline silicon.

16. The spectral filter according to claim 1, wherein, The thickness of the first metal reflective layer and the thickness of the second metal reflective layer are 10 nm to 80 nm.

17. The spectral filter according to claim 1, further comprising: Multiple dielectric layers are disposed above or below the multiple cavities and have multiple different effective refractive indices.

18. An image sensor, comprising: Spectral filter; as well as A pixel array that receives light transmitted through the spectral filter. The spectral filter includes: Resonators, including - First metallic reflective layer; - A second metal reflective layer is disposed above the first metal reflective layer; - Multiple cavities are disposed between the first metal reflective layer and the second metal reflective layer; and A bandpass filter is disposed below the first metal reflective layer or above the second metal reflective layer. The bandpass filter includes multiple frequency band filters that transmit light in multiple wavelength regions. The plurality of frequency band filters are configured to correspond to the plurality of cavities. Each of the multiple frequency band filters transmits light in the corresponding wavelength region. Each of the plurality of cavities corresponding to the plurality of frequency band filters has a plurality of center wavelengths, one of which is included in the corresponding wavelength region of the corresponding frequency band filter corresponding to the cavity, and At least one of the plurality of cavities includes a substrate and at least one pattern disposed in the substrate in a shape.

19. The image sensor according to claim 18, wherein, The pixel array includes a plurality of pixels, and each of the plurality of pixels includes a wiring layer and a photodiode disposed on the wiring layer, the wiring layer including a driving circuit.

20. The image sensor according to claim 19, wherein, The plurality of frequency band filters include a first frequency band filter that transmits light in a first wavelength region, a second frequency band filter that transmits light in a second wavelength region, and a third frequency band filter that transmits light in a third wavelength region.

21. The image sensor according to claim 20, wherein, The plurality of cavities includes a first cavity corresponding to the first frequency band filter, a second cavity corresponding to the second frequency band filter, and a third cavity corresponding to the third frequency band filter.

22. The image sensor according to claim 21, wherein, The first cavity has a plurality of first center wavelengths including a center wavelength in the first wavelength region, the second cavity has a plurality of second center wavelengths including a center wavelength in the second wavelength region, and the third cavity has a plurality of third center wavelengths including a center wavelength in the third wavelength region.

23. The image sensor according to claim 22, wherein, The refractive indices of the first cavity, the second cavity, and the third cavity are different.

24. The image sensor according to claim 23, wherein, The thickness of the first cavity, the thickness of the second cavity, and the thickness of the third cavity are the same.

25. The image sensor according to claim 18, wherein, The spectral filter further includes multiple dielectric layers disposed above or below the multiple cavities, and having multiple effective refractive indices.

26. The image sensor of claim 18 further includes a timing controller, a line decoder, and an output circuit.

27. An electronic device comprising the image sensor of claim 18.

28. The electronic device according to claim 27, wherein, The electronic devices include mobile phones, smartphones, tablet computers, smart tablet computers, digital cameras, camcorders, laptop computers, televisions, smart TVs, smart refrigerators, security cameras, robots, or medical cameras.

29. A spectral filter, comprising: Resonator array, including: - First metallic reflective layer; - Second metallic reflective layer; and - Multiple multi-mode cavities are disposed between the first metal reflective layer and the second metal reflective layer, wherein the thickness of the multiple multi-mode cavities is uniform; and A filter array, disposed below or above the resonator array, comprising multiple filters that transmit light in multiple wavelength regions. In this configuration, one of the multiple filters corresponds to one or more of the multiple multimode cavities, and the filter transmits light from a corresponding wavelength region among the multiple wavelength regions. Each of the plurality of multimode cavities has a plurality of center wavelengths, one of which is included in the corresponding wavelength region of the filter corresponding to the multimode cavity. At least one of the plurality of multi-mode cavities includes a substrate and at least one pattern disposed in the substrate in a shape.

30. The spectral filter according to claim 29, wherein, One of the plurality of multimode cavities includes a first dielectric pattern, such that the one multimode cavity has a first effective refractive index; and another multimode cavity includes a second dielectric pattern, such that the other multimode cavity has a second effective refractive index.

Images