An image sensor includes a substrate, a first thin lens configured to concentrate light of a first wavelength, and including a plurality of first scatterers disposed on the substrate. The plurality of first scatterers includes a material having a refractive index greater than a refractive index of the substrate. The image sensor further includes a plurality of light-sensing cells configured to sense the light concentrated by the first thin lens.
1. An image sensor comprising:
a substrate;
a first thin lens configured to concentrate light of a first wavelength, and comprising a plurality of first scatterers disposed on the substrate, wherein the plurality of first scatterers comprises a material having a refractive index greater than a refractive index of the substrate;
a low-refractive index material layer covering the plurality of first scatterers, and comprising a material having a refractive index less than the refractive index of the material of the plurality of first scatterers,
wherein the first thins lens further comprise a plurality of second scatterers disposed on the low-refractive index material layer and comprising a material having a refractive index greater than the refractive index of the material of the low-refractive index material layer, and
a plurality of light-sensing cells configured to sense the light concentrated by the first thin lens.
2. The image sensor of claim 1 , further comprising a housing configured to fix the first thin lens and the plurality of light-sensing cells, while maintaining a distance between the first thin lens and the plurality of light-sensing cells.
3. The image sensor of claim 1 , wherein each of the plurality of first scatterers and the plurality of second scatterers has a pillar shape.
4. The image sensor of claim 1 , wherein each of the plurality of first scatterers and the plurality of second scatterers has a shape dimension less than the first wavelength.
5. The image sensor of claim 1 , wherein each of a distance between the plurality of first scatterers and a distance between the second scatterers is less than the first wavelength.
6. The image sensor of claim 1 , further comprising a second thin lens configured to concentrate light of a second wavelength different from the first wavelength, and comprising:
a plurality of third scatterers disposed on the substrate, and comprising a material having a refractive index greater than the refractive index of the substrate; and
a plurality of fourth scatterers disposed on a layer different from the plurality of third scatterers, and spaced apart from the third scatterers.
7. The image sensor of claim 6 , wherein each of the plurality of third scatterers and the plurality of fourth scatterers has shape dimension less than the second wavelength.
8. The image sensor of claim 6 , wherein each of a distance between the plurality of third scatterers and a distance between the plurality of fourth scatterers is less than the second wavelength.
9. The image sensor of claim 6 , wherein the low-refractive index material layer is covering the plurality of third scatterers, and
wherein the plurality of fourth scatterers are disposed on the low-refractive material layer.
10. The image sensor of claim 6 , wherein a shape distribution of the plurality of first scatterers and the plurality of second scatterers included in the first thin lens is different from a shape distribution of the plurality of third scatterers and the plurality of fourth scatterers included in the second thin lens.
11. The image sensor of claim 6 , further comprising an optical filter configured to filter incident light such that the light of the first wavelength and the light of the second wavelength are respectively incident on the first thin lens and the second thin lens.
12. The image sensor of claim 1 , further comprising a second thin lens configured to concentrate the light of the first wavelength, and having a focal length different from a focal length of the first thin lens,
wherein the second thin lens comprises:
a plurality of third scatterers disposed on the substrate, and comprising a material having a refractive index greater than the refractive index of the substrate; and
a plurality of fourth scatterers disposed on a layer different from the plurality of third scatterers, and spaced apart from the third scatterers.
13. The image sensor of claim 12 , further comprising a depth map calculator configured to:
calculate a defocusing degree of the light concentrated by the first thin lens and the light concentrated by the second thin lens that are sensed by the plurality of light-sensing cells; and
calculate depth map information of an image that is represented by the light concentrated by the first thin lens and the light concentrated by the second thin lens that are sensed by the plurality of light-sensing cells, based on the calculated defocusing degree.
14. The image sensor of claim 12 , further comprising a third thin lens configured to concentrate light having a second wavelength different from the first wavelength, and comprising:
a plurality of fifth scatterers disposed on the substrate, and comprising a material having a refractive index greater than the refractive index of the substrate; and
a plurality of sixth scatterers disposed on a layer different from the plurality of third scatterers, and spaced apart from the fifth scatterers.
15. The image sensor of claim 14 , wherein each of the plurality of fifth scatterers and the plurality of sixth scatterers has a shape dimension less than the second wavelength.
16. The image sensor of claim 14 , wherein each of a distance between the plurality of fifth scatterers and a distance between the sixth scatterers is less than the second wavelength.
17. The image sensor of claim 14 , wherein a shape distribution of the plurality of fifth scatterers and the plurality of sixth scatterers included in the third thin lens is different from a shape distribution of the plurality of first scatterers and the plurality of second scatterers included in the first thin lens and from a shape distribution of the plurality of third scatterers and the plurality of fourth scatterers included in the second thin lens.
18. The image sensor of claim 14 , further comprising a fourth thin lens configured to concentrate the light of the second wavelength, and having a focal length different from a focal length of the third thin lens,
wherein the second thin lens comprises:
a plurality of seventh scatterers disposed on the substrate, and comprising a material having a refractive index greater than the refractive index of the substrate; and
a plurality of eighth scatterers disposed on a layer different from the plurality of seventh scatterers, and spaced apart from the seventh scatterers.
19. The image sensor of claim 18 , wherein a shape distribution of the plurality of seventh scatterers and the plurality of eighth scatterers included in the fourth thin lens is different from a shape distribution of the plurality of fifth scatterers and the plurality of sixth scatterers included in the third thin lens.