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. A spectral camera 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 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;
a transparent substrate which is apart from the sensor; and
a light blocking layer provided between the plurality of lens units,
wherein the optical filter, the imaging lens array, and the light blocking layer are provided on the transparent substrate, and
wherein the light blocking layer is provided at positions corresponding to boundaries between the plurality of band filter units.
2. The spectral camera of claim 1 , wherein the optical filter is provided on a first surface of the transparent substrate, and the imaging lens array is provided on a second surface of the transparent substrate, the second surface being opposite to the first surface.
3. The spectral camera of claim 1 , wherein the optical filter and the imaging lens array are provided on a surface of the transparent substrate.
4. The spectral camera of claim 3 , further comprising an intermediate layer provided between the optical filter and the imaging lens array.
5. A spectral camera, 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 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;
a transparent substrate which is apart from the sensor; and
a light blocking layer provided between the plurality of lens units,
wherein the optical filter is provided on the transparent substrate, and the imaging lens array is provided on the sensor, and
wherein the light blocking layer is provided at positions corresponding to boundaries between the plurality of band filter units.
6. The spectral camera of claim 1 , further comprising an additional filter, which is provided on the sensor or the transparent substrate and 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.
7. The spectral camera of claim 6 , wherein the plurality of additional filter units comprise a plurality of color filter units or a plurality of broadband filter units.
8. The spectral camera of claim 1 , wherein each of the plurality of lens units comprises at least one convex lens.
9. The spectral camera of claim 1 , wherein each of the plurality of lens units comprises a flat lens or a meta lens.
10. The spectral camera 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.
11. The spectral camera of claim 10 , wherein the cavity layer comprises a single material layer or a plurality of material layers having different refractive indexes.
12. The spectral camera of claim 10 , 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.
13. The spectral camera of claim 10 , wherein the Bragg reflection layers comprise at least three material layers having different refractive indexes.
14. The spectral camera of claim 1 , wherein each of the plurality of band filter units has a photonic crystal structure or a nano-post structure.
15. The spectral camera of claim 1 , wherein the sensor comprises an image sensor or a photodiode.
16. A spectral camera 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 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;
a transparent substrate which is apart from the sensor; and
a light blocking layer provided between the plurality of lens units,
wherein the imaging lens array and the light blocking layer are provided on a first surface of the transparent substrate, the first surface facing toward the optical filter, and the optical filter is provided on the sensor, and
wherein the light blocking layer is provided at positions corresponding to boundaries between the plurality of band filter units.