Multi-point spectral system and multi-point spectral module to be mounted on, clipped on or connected to an image capturing module of an electronic device easily
A multi-point spectral system includes an imaging lens, an image capturing module and a multiwavelength filter (MWF) disposed between the imaging lens and the image capturing module. The MWF has a plurality of narrow-bandpass filter (NBPF) units arranged in an array, and each of the plurality of NBPF units has a respective predetermined central transmitted wavelength. The multi-point spectral system is provided to capture plural spectral images of a scene, which contain spectral or color information of the scene. The multi-point spectral system may utilize the information of the plural spectral images to recognize features revealed at the scene.
1. A multi-point spectral system, comprising:
a multiwavelength filter (MWF) including a plurality of narrow-bandpass filter (NBPF) units arranged in an array, each of the plurality of NBPF units having a respective predetermined central transmitted wavelength;
an imaging lens provided to form a plurality of duplicated images of a scene onto the plurality of NBPF units, respectively; and
an image capturing module including a color-image sensing element, wherein the color-image sensing element has an image-sensing region divided into a plurality of image-sensing areas corresponding to the plurality of NBPF units, respectively, and each of the plurality of image-sensing areas includes plural color micro-units arranged in an array, wherein the color micro-units include a plurality of red color micro-units, a plurality of green color micro-units, and a plurality of blue color micro-units, and each of the plural color micro-units has a wavelength band of responsive spectrum;
wherein the MWF is located between the imaging lens and the image capturing module, and the image capturing module captures the plurality of duplicated images of the scene, and
wherein each of the plurality of NBPF units includes a transmitted wavelength band, and the transmitted wavelength band of the NBPF unit is narrower than the wavelength band of responsive spectrum of the color micro-unit.
2. The multi-point spectral system of claim 1 , wherein at least two of the plurality of NBPF units have different predetermined central transmitted wavelengths.
3. The multi-point spectral system of claim 1 , wherein the imaging lens and the MWF are assembled together in a multi-point spectral module.
4. The multi-point spectral system of claim 1 , wherein each of the plurality of NBPF units has a Fabry-Perot filter structure.
5. The multi-point spectral system of claim 4 , wherein the Fabry-Perot filter structure includes a spacer between two reflectors, and the two reflectors are made of dielectric films or metallic films.
6. The multi-point spectral system of claim 1 , wherein the image capturing module further includes a built-in imaging lens, and the built-in imaging lens is in front of the color-image sensing element.
7. The multi-point spectral system of claim 1 , wherein the color-image sensing element is a color charge-coupled device sensor or a color complementary metal-oxide semiconductor sensor.
8. The multi-point spectral system of claim 1 , wherein the imaging lens includes a micro-lens array.
9. The multi-point spectral system of claim 1 , further comprising a processing device provided to process the plurality of duplicated images.
10. The multi-point spectral system of claim 9 , wherein the processing device includes:
an image synthesis unit configured to synthesize the plurality of duplicated images of the scene into information of plural spectral distributions of the scene;
a segmentation unit configured to partition an image of the scene into plural regions;
a feature extracting unit configured to extract one or more spectral features of the plural partitioned regions; and
a first categorizing unit configured to execute a categorized algorithm between the spectral features of each partitioned region of the image and stored spectral features in a database unit, and produce one or more similarity results.
11. The multi-point spectral system of claim 10 , wherein the feature extracting unit executes a principal components analysis (PCA) to extract the one or more spectral features.
12. The multi-point spectral system of claim 10 , wherein the first categorizing unit executes a comparison by calculating plural Euclidean distances between the spectral features of the plural partitioned regions and the stored spectral features in the database unit, converts the Euclidean distances into plural similarity values, and outputs most five of the plural similarity values as the similarity results.
13. The multi-point spectral system of claim 12 , wherein the processing device further includes a second categorizing unit, and the second categorizing unit executes an unmixing process to the similarity results which are less than a threshold value, and produces new similarity results.
14. The multi-point spectral system of claim 13 , wherein each of the plural partitioned regions includes plural pixels, and a set including one or more of the pixels is regarded as a minimum processed unit by the feature extracting unit.
15. The multi-point spectral system of claim 14 , wherein the second categorizing unit further categorizes each pixel of the plural partitioned regions into plural categories according to the new similarity results, and produces an averaged spectrum with pixels in a same category for recognition.
16. A multi-point spectral module being mounted on, clipped on or connected to an image capturing module of an electronic device with ease, comprising:
a multiwavelength filter includes a plurality of narrow-bandpass filter (NBPF) units arranged in an array, each of the plurality of NBPF units having a predetermined central transmitted wavelength, respectively; and
an imaging lens provided to form a plurality of duplicated images of a scene onto the plurality of NBPF units, respectively,
wherein the image capturing module includes a color-image sensing element having an image-sensing region divided into a plurality of image-sensing areas corresponding to the plurality of NBPF units, respectively, and each of the plurality of image-sensing areas includes plural color micro-units arranged in an array, and wherein the color micro-units include a plurality of red color micro-units, a plurality of green color micro-units, and a plurality of blue color micro-units, and each of the plural color micro-units has a wavelength band of responsive spectrum, and
wherein each of the plurality of NBPF units includes a transmitted wavelength band, and the transmitted wavelength band of the NBPF unit is narrower than the wavelength band of responsive spectrum of the color micro-unit.