Radiance sensor and radiance reconstruction method

• US 10,228,279 B2
• Filed: 04/21/2017
• Issued: 03/12/2019
• Est. Priority Date: 04/21/2016
• Status: Active Grant

• Current Assignee: Arizona Board of Regents (University of Arizona)
• Original Assignee: Arizona Board of Regents (University of Arizona)
• Inventors: Caucci, Luca, Barrett, Harrison
• Primary Examiner(s): Le, Que T
• Application Number:
  US15/494,351
• Publication Number:
  US 20170307439A1
• Time in Patent Office: 690 Days
• Field of Search: 250205
• CPC Class Codes: G01J 1/0219 Electrical interface; User interface
• CPC Class Codes: G01J 1/0228 Control of working procedures; Failure detection; Spectral bandwidth calculation
• CPC Class Codes: G01J 1/0266 Field-of-view determination; Aiming or pointing of a photometer; Adjusting alignment; Encoding angular position; Size of the measurement area; Position tracking; Photodetection involving different fields of view for a single detector
• CPC Class Codes: G01J 1/0407 Optical elements not provided otherwise, e.g. manifolds, windows, holograms, gratings
• CPC Class Codes: G01J 1/0411 using focussing or collimating elements, i.e. lenses or mirrors; Aberration correction
• CPC Class Codes: G01J 1/0414 using plane or convex mirrors, parallel phase plates, or plane beam-splitters
• CPC Class Codes: G01J 1/0437 using masks, aperture plates, spatial light modulators, spatial filters, e.g. reflective filters
• CPC Class Codes: G01J 1/0448 Adjustable, e.g. focussing
• CPC Class Codes: G01J 1/4228 arrangements with two or more detectors, e.g. for sensitivity compensation
• CPC Class Codes: G02B 21/367 providing an output produced by processing a plurality of individual source images, e.g. image tiling, montage, composite images, depth sectioning, image comparison
• CPC Class Codes: G02B 27/0075 with means for altering, e.g. increasing, the depth of field or depth of focus

Abstract

A radiance sensor includes a memory and a microprocessor. The memory stores non-transitory computer-readable instructions and adapted to store a plurality of electrical signals output from a photodetector array in response to electromagnetic radiation transmitted through a lenslet array and incident on the photodetector array. The microprocessor is adapted to execute the instructions to (i) determine irradiance of the electromagnetic radiation in a detector plane from the plurality of electrical signals, each electrical signal having generated by a respective one of a plurality of photodetectors of the photodetector array, and (ii) reconstruct, from the determined irradiance, the 4D-radiance in an input plane, the lenslet array being between the input plane and the detector plane.

Claims

1. A radiance sensor comprising:

a lenslet array;

a photodetector array located in a detector plane, and including a plurality of photodetectors configured to generate a respective one of a plurality of electrical signals output in response to electromagnetic radiation transmitted by the lenslet array and incident on the photodetector array;

memory configured to store non-transitory computer-readable instructions and the plurality of electrical signals;

a microprocessor configured to execute the instructions to;

determine irradiance of the electromagnetic radiation in the detector plane from the plurality of electrical signals; and

reconstruct, from the determined irradiance, a radiance field in an input plane, the lenslet array being between the input plane and the detector plane.

2. The radiance sensor of claim 1, the lenslet array having a plurality of lenslets of focal length f, the photodetector array being located a distance d≥

f behind the lenslet array.

3. The radiance sensor of claim 1, the microprocessor being further configured to, when executing the instructions to reconstruct, apply a pseudoinverse operator to data corresponding to the determined irradiance.

4. A radiance sensor comprising:

memory storing non-transitory computer-readable instructions and adapted to store a plurality of electrical signals output from a photodetector array in response to electromagnetic radiation transmitted through a lenslet array and incident on the photodetector array;

a microprocessor configured to execute the instructions to;

determine irradiance of the electromagnetic radiation in a detector plane from the plurality of electrical signals, each electrical signal having generated by a respective one of a plurality of photodetectors of the photodetector array; and

reconstruct, from the determined irradiance, the 4D-radiance in an input plane, the lenslet array being between the input plane and the detector plane.

5. The radiance sensor of claim 4, further comprising the lenslet array, the photodetector array located behind the lenslet array in a plane substantially parallel to a plane of the lenslet array.

6. The radiance sensor of claim 4, the lenslet array having a plurality of lenslets of focal length f, the photodetector array being located a distance q≥

f behind the lenslet array.

7. The radiance sensor of claim 4, a microprocessor being further configured to, when executing the instructions to reconstruct, apply a pseudoinverse operator to data corresponding to the determined irradiance.

8. A method for reconstructing 4D-radiance of electromagnetic radiation transmitted through a lenslet array and detected by a photodetector array in a detector plane, comprising:

determining irradiance of the electromagnetic radiation in the detector plane from a plurality of electrical signals, each of the plurality of electrical signals having been generated by a respective one of a plurality of photodetectors of the photodetector array in response to a respective one of a plurality of spatial regions of the electromagnetic radiation; and

reconstructing, from the determined irradiance, the 4D-radiance in an input plane, the lenslet array being between the input plane and the detector plane.

9. The method of claim 8, further comprising generating each of the plurality of electrical signals by detecting the electromagnetic radiation with the photodetector array.

10. The method of claim 8, the lenslet array having a plurality of lenslets of focal length f, the photodetector array being located a distance q≥

f behind the lenslet array.

11. The method of claim 8, the step of reconstructing comprising applying a pseudoinverse operator to data corresponding to the determined irradiance.