Solid-state imaging device, camera and signal processing method
View Patent ↗The solid-state imaging device of the present invention includes: photodiodes which are two-dimensionally arranged; light condensers each of which condenses light and is provided in a position to correspond to two of the photodiodes which are adjacent to each other; and separating units each of which separates the light entering through the light condensers into first light having a wavelength within a predetermined range, and second light having a wavelength out of the predetermined range, and is provided in a position to correspond to one of the light condensers. Each of the separating units includes: a light-selecting unit which selectively allows transmission of one of the first light and the second light and reflect the other one of the first light and the second light, and allow entering of the transmitted light to one of the corresponding two of the photodiodes; and a light-reflecting unit which reflects the light, reflected by the light-selecting unit, towards the other one of the corresponding two of the photodiodes.
1. A solid-state imaging device comprising:
photodiodes which are two-dimensionally arranged;
light condensers each of which condenses light and is positioned to correspond to two of said photodiodes which are adjacent to each other; and
light separators each of which is operable to separate the light entering through said light condensers into first light having a wavelength within a predetermined range, and second light having a wavelength out of the predetermined range, each light separator positioned to correspond to one of said light condensers,
wherein each of said light separators includes:
a light selector operable to selectively allow transmission of one of the first light and the second light and reflect the other one of the first light and the second light, and to allow the transmitted light to enter one of the corresponding two of said photodiodes; and
a light reflector operable to reflect the light, reflected by said light selector, towards the other one of the corresponding two of said photodiodes,
wherein said light separators include first type light separators and second type light separators,
wherein the first light separated by said first type light separators is first primary color light indicating a first primary color, among red, green and blue, and the second light separated by said first type light separators is a first complementary color light indicating a color which is complementary to the first primary color, and
wherein the first light separated by said second type light separators is second primary color light indicating a second primary color which is different from the first primary color, and the second light separated by said second type light separators is a second complementary color light indicating a color which is complementary to the second primary color.
2. The solid-state imaging device according to claim 1 ,
wherein said light reflector is operable to reflect only visible light.
3. The solid-state imaging device according to claim 1 , further comprising
a light remover operable to remove infrared light,
wherein each of said light separators is operable to separate light from which the infrared light is removed by said light remover, into the first light and the second light.
4. The solid-state imaging device according to claim 1 ,
wherein the first primary color light, the first complementary color light, the second primary color light, and the second complementary color light are red light, cyan light, blue light and yellow light, respectively,
said first type light separators are arranged in the same rows or columns, and
said second type light separators are arranged in the same rows or columns.
5. The solid-state imaging device according to claim 1 ,
wherein the first primary color light, the first complementary color light, the second primary color light, and the second complementary color light are red light, cyan light, green light and magenta light, respectively,
said first type light separators are arranged in the same rows or columns, and
said second type light separators are arranged in the same rows or columns.
6. The solid-state imaging device according to claim 1 , further comprising
a color converter operable to convert signals respectively indicating the first primary color, the first complementary color, the second primary color, and the second complementary color, obtained from said photodiodes, into a red color signal, a green color signal and a blue color signal.
7. The solid-state imaging device according to claim 1 ,
wherein said light selector and one of the corresponding two of said photodiodes are arranged along an optical axis of the light condensed by the corresponding one of said light condensers.
8. The solid-state imaging device according to claim 7 ,
wherein said light condensers are arranged in such manner that the respective centers of said light condensers in a row are shifted from the respective centers of said light condensers in a vertically adjacent row by a distance between the respective centers of two of said photodiodes which are horizontally adjacent.
9. The solid-state imaging device according to claim 1 ,
wherein a vertical arrangement pitch and a horizontal arrangement pitch of said light condensers differ from each other.
10. The solid-state imaging device according to claim 1 ,
wherein said light selector is a multilayer film which includes two types of optical films having different refractive indices,
the optical thickness of each of said optical films is equal to a quarter of a set center wavelength, and
the multilayer film further includes an insulator layer having a photonic structure which is structured based on the set center wavelength.
11. The solid-state imaging device according to claim 10 ,
wherein said light reflector is operable to reflect only visible light.
12. The solid-state imaging device according to claim 10 further comprising
a light remover operable to remove infrared light,
wherein each of said light separators is operable to separate light in which the infrared light is removed by said light remover into the first light and the second light.
13. The solid-state imaging device according to claim 1 ,
wherein said light selector is a multilayer film which includes two types of optical films having different refractive indices,
the optical thickness of each of said optical films is equal to a quarter of a set center wavelength, and
the multilayer film further includes an insulator layer having an optical thickness different than a quarter of the set center wavelength.
14. The solid-state imaging device according to claim 13 ,
wherein said light reflector is operable to reflect only visible light.
15. The solid-state imaging device according to claim 13 , further comprising
a light remover operable to remove infrared light,
wherein each of said light separators is operable to separate light in which the infrared light is removed by said light remover into the first light and the second light.
16. A camera comprising a solid-state imaging device,
wherein said solid-state imaging device includes:
photodiodes which are two-dimensionally arranged;
light condensers each of which condenses light and is positioned to correspond to two of said photodiodes which are adjacent to each other; and
light separators each of which is operable to separate the light entering through said light condensers into first light having a wavelength within a predetermined range, and second light having a wavelength out of the predetermined range, each light separator positioned to correspond to one of said light condensers,
wherein each of said light separators has:
a light selector operable to selectively allow transmission of one of the first light and the second light and reflect the other one of the first light and the second light, and to allow the transmitted light to enter one of the corresponding two of said photodiodes; and
a light reflector operable to reflect the light, reflected by said light selector, towards the other one of the corresponding two of said photodiodes,
wherein said light separators include first type light separators and second type light separators,
wherein the first light separated by said first type light separators is first primary color light indicating a first primary color, among red, green and blue, and the second light separated by said first type light separators is a first complementary color light indicating a color which is complementary to the first primary color, and
wherein the first light separated by said second type light separators is second primary color light indicating a second primary color which is different from the first primary color, and the second light separated by said second type light separators is a second complementary color light indicating a color which is complementary to the second primary color.
17. A signal processing method for use in a solid-state imaging device,
wherein the solid-state imaging device includes:
photodiodes which are two-dimensionally arranged;
light condensers each of which condenses light and is positioned to correspond to two of the photodiodes which are adjacent to each other; and
light separators each of which is operable to separate the light entering through the light condensers into first light having a wavelength within a predetermined range, and second light having a wavelength out of the predetermined range, each light separator positioned to correspond to one of the light condensers,
wherein each of the light separators has:
a light selector operable to selectively allow transmission of one of the first light and the second light and reflect the other one of the first light and the second light, and to allow the transmitted light to enter one of the corresponding two of the photodiodes; and
a light reflector operable to reflect the light, reflected by the light selector, towards the other one of the corresponding two of the photodiodes, and
the light separators have first type light separators and second type light separators,
wherein the first light separated by the first type light separators is first primary color light indicating a first primary color, among red, green and blue, and the second light separated by the first type light separators is a first complementary color light indicating a color which is complementary to the first primary color, and
the first light separated by the second type light separators is second primary color light indicating a second primary color which is different from the first primary color, and the second light separated by the second type light separators is a second complementary color light indicating a color which is complementary to the second primary color,
said signal processing method comprising:
obtaining, from four of said photodiodes to which the first primary color light, the first complementary color light, the second primary color light and the second complementary color light enter by one of the first type light separators and one of the second type light separators, signals respectively indicating the first primary color, the first complementary color, the second primary color, and the second complementary color; and
converting the obtained four signals into a red color signal, a green color signal and a blue color signal.