Spectral imaging apparatus
Provided is a spectral imaging apparatus. The spectral imaging apparatus includes: an optical filter including a plurality of band filter units having different center wavelengths; a sensing device configured to receive light passing through the optical filter; an imaging lens array including a plurality of lens units which respectively correspond to the plurality of band filter units and each implement imaging on the sensing device; and a transparent substrate which is apart from the sensing device. At least one of the optical filter and the imaging lens array is provided on the transparent substrate.
1. An image sensing device comprising:
an optical filter comprising a plurality of band filter units, the plurality of band filter units having different center wavelengths;
a sensor configured to receive light passing through the optical filter, and convert the light into an electrical signal to perform imaging of an object;
an imaging lens array which is apart from the optical filter, comprising a plurality of lens units which respectively correspond to the plurality of band filter units, the plurality of lens units forming a focus of the imaging of the sensor; and
a light blocking layer provided between the plurality of lens units,
wherein the light blocking layer is provided at positions corresponding to boundaries between the plurality of band filter units.
2. The image sensing device of claim 1 , wherein the optical filter and the imaging lens array are apart from the sensor.
3. The image sensing device of claim 1 , wherein the optical filter is provided on the sensor.
4. The image sensing device of claim 1 , wherein the imaging lens array is provided on the sensor.
5. The image sensing device of claim 1 , further comprising an additional filter, which comprises a plurality of additional filter units, the plurality of additional filter units respectively corresponding to the plurality of band filter units and configured to transmit specific wavelength bands.
6. The image sensing device of claim 5 , wherein the plurality of additional filter units comprise a plurality of color filter units or a plurality of broadband filter units.
7. The image sensing device of claim 1 , wherein each of the plurality of lens units comprises at least one convex lens.
8. The image sensing device of claim 1 , wherein each of the plurality of lens units comprises a flat lens or a meta lens.
9. The image sensing device of claim 1 , wherein each of the plurality of band filter units comprises:
a cavity layer; and
Bragg reflection layers respectively provided on an upper surface and a lower surface of the cavity layer.
10. The image sensing device of claim 9 , wherein the cavity layer comprises a single material layer or a plurality of material layers having different refractive indexes.
11. The image sensing device of claim 9 , wherein the cavity layer has a thickness greater than λ/n, where λ refers to a center wavelength of a corresponding band filter unit, and n refers to an effective refractive index of the cavity layer.
12. The image sensing device of claim 9 , wherein the Bragg reflection layers comprise at least three material layers having different refractive indexes.
13. The image sensing device of claim 1 , wherein each of the plurality of band filter units has a photonic crystal structure or a nano-post structure.
14. The image sensing device of claim 1 , wherein the sensor comprises an image sensor or a photodiode.