Coded aperture snapshot spectral imager and method therefor

A method for providing a spectral image of a scene, wherein the method comprises:

• (1) projecting a plurality of first images of the scene onto a first image plane, wherein the plurality of first images is based on light from the scene that comprises a plurality of spectral components, and wherein each of the plurality of first images is uniquely characterized by a different one of the plurality of spectral components, and further wherein the plurality of first images are interspersed on the first image plane, the plurality of first images being formed by operations comprising;
• (i) imaging the scene onto a first coded aperture located at a second image plane, the first coded aperture haying an aperture pattern that is based on the number of spectral components in the plurality of spectral components, wherein the first coded aperture transmits a plurality of sub-images of the scene, and wherein each of the plurality of sub-images comprises the plurality of spectral components;
• and
• (ii) imaging the first coded aperture onto the first image plane through a first disperser that disperses the spectral components of each of the plurality of sub-images along a first dimension on the first image plane;
• and
• (2) receiving the plurality of first images at a photodetector array that is located at the first image plane, wherein each photodetector in the photodetector array receives light that is characterized by only one of the plurality of spectral components.

A method for providing a spectral image of a scene, the method comprising:

• (1) projecting a plurality of first images of the scene onto a first image plane, wherein the plurality of first images is based on light from the scene that comprises a plurality of spectral components, and wherein each of the plurality of first images is uniquely characterized by a different one of the plurality of spectral components, and further wherein the plurality of first images are interspersed on the first image plane, the plurality of first images being formed by operations comprising;
• (i) providing a first coded aperture that has an aperture pattern, wherein the aperture pattern is based on the number of spectral components in the plurality of spectral components;
• (ii) imaging the scene onto the first coded aperture, wherein the first coded aperture is located at a second image plane, and wherein the scene is imaged onto the first coded aperture through a first disperser that induces a first dispersion along a first dimension;
• (iii) transmitting the imaged scene through the first coded aperture;
• and
• (iv) imaging the first coded aperture onto the first image plane, wherein the first coded aperture is imaged through a second disperser, and wherein the second disperser removes the induced first dispersion;
• and
• (2) receiving the plurality of first images at a photodetector array that is located at the first image plane, wherein each photodetector in the photodetector array receives light that is characterized by only one of the plurality of spectral components.

A method for providing a spectral image of a scene, the method comprising:

• (1) projecting a plurality of first images of the scene onto a first image plane, wherein the plurality of first images is based on light from the scene that comprises a plurality of spectral components, and wherein each of the plurality of first images is uniquely characterized by a different one of the plurality of spectral components, and further wherein the plurality of first images are interspersed on the first image plane, the plurality of first images being formed by operations comprising;
• (i) providing a first coded aperture that has an aperture pattern, wherein the aperture pattern is based on the number of spectral components in the plurality of spectral components;
• (ii) imaging the scene onto a first coded aperture, wherein the first coded aperture is located at a second image plane;
• (iii) imaging the first coded aperture onto a second coded aperture located at a third image plane, wherein the first coded aperture is imaged onto the second coded aperture through first disperser that induces a first dispersion along a first dimension;
• and
• (iv) imaging the second coded aperture onto the first image plane, wherein the second coded aperture is imaged onto the first image plane through a second disperser, and wherein the second disperser is less dispersive than the first disperser;
• and
• (2) receiving the plurality of first images at a photodetector array that is located at the first image plane, wherein each photodetector in the photodetector array receives light that is characterized by only one of the plurality of spectral components.

A method for providing a spectral image of a scene, wherein the method comprises:

• providing a coded aperture, wherein the coded aperture comprises an array of fields, and wherein each field has n rows of regions aligned with a first dimension and n columns of regions, where n is the number of spectral components in the plurality of spectral components, and wherein each row comprises 1 transmissive region and (n−1) non-transmissive regions, and further wherein no two transmissive region within the coded aperture are contiguous;
• forming a first image of the scene on the coded aperture, wherein the first image is based on light from the scene that comprises a plurality of spectral components;
• imaging the coded aperture through a disperser to form a plurality of second images on a first image plane, wherein each of the plurality of second images is uniquely characterized by a different one of the plurality of spectral components, and wherein the plurality of second images are dispersed along the first dimension on the first image plane, and further wherein the plurality of second images are interspersed on the first image plane;
• and
• receiving the plurality of second images at a photodetector array that is located at a second image plane, wherein each photodetector in the photodetector array receives light that is characterized by only one of the plurality of spectral components.

A method for collecting spatio-spectral information from a scene, wherein the method comprises:

• providing a coded aperture, wherein the coded aperture comprises an array of fields, and wherein each field has n rows of regions aligned with a first dimension and n columns of regions, where n is the number of spectral components in the plurality of spectral components, and wherein each row comprises 1 transmissive region and (n−1) non-transmissive regions, and further wherein no two transmissive region within the coded aperture are contiguous;
• forming a first image of the scene at a coded aperture, wherein the first image is based on light from the scene that comprises a plurality of spectral components, and wherein the first image is formed through a first disperser that induces a first spectral dispersion on the first image;
• forming a plurality of second images at a first image plane by imaging the coded aperture onto the first image plane through a second disperser, wherein the second disperser removes the first dispersion;
• and
• receiving the plurality of second images at a photodetector array located at the first image plane, wherein each of the plurality of second images is uniquely characterized by a different one of the plurality of spectral components, and wherein the plurality of second images are interspersed, and further wherein each photodetector of the photodetector array receives light that is characterized by only one of the plurality of spectral components.

A method for collecting spatio-spectral information from a scene, wherein the method comprises:

• providing a first coded aperture and a second coded aperture, wherein each of the first coded aperture and second coded aperture comprises an array of fields, and wherein each field has n rows of regions aligned with a first dimension and n columns of regions, where n is the number of spectral components in the plurality of spectral components, and wherein each row comprises 1 transmissive region and (n−1) non-transmissive regions, and further wherein no two transmissive region within each of the first coded aperture and second coded aperture are contiguous;
• forming a first image of the scene on the first coded aperture, wherein the first image is based on light from the scene that comprises a plurality of spectral components;
• forming a second image of the first coded aperture on the second coded aperture, wherein the second image is formed through a first disperser that is characterized by a first dispersion;
• forming a plurality of third images on a first image plane by imaging the second coded aperture onto the first image plane through a second disperser that is characterized by a second dispersion that is less than the first dispersion;
• and
• receiving the plurality of third images at a photodetector array located at the first image plane, wherein each of the plurality of third images is uniquely characterized by a different one of the plurality of spectral components, and wherein the plurality of third images are interspersed, and further wherein each photodetector of the photodetector array receives light that is characterized by only one of the plurality of spectral components.