System and method for imaging with pinhole arrays

Patent metadata

Field	Value
Publication number	US-10033996-B2
Application number	US-201515117356-A
Country	US
Kind code	B2
Filing date	Feb 5, 2015
Priority date	Feb 6, 2014
Publication date	Jul 24, 2018
Grant date	Jul 24, 2018

Abstract

A method and system are provided, for imaging a region of interest with pinhole based imaging. The method comprising: collecting input radiation from the region of interest through a selected set of a plurality of a predetermined number of aperture arrays, each array having a predetermined arrangement of apertures and collecting the input radiation during a collection time period, wherein said selected set of the aperture arrays and the corresponding collection time periods defining a total effective transmission function of the radiation collection, generating image data from the collected input radiation, said image data comprising said predetermined number of image data pieces corresponding to the input radiation collected through the aperture arrays respectively, processing the image data pieces utilizing said total effective transmission function of the radiation collection, and determining a restored image of the region of interest. The set of aperture arrays is preferably selected such that said total effective transmission function provides non-null transmission for spatial frequencies being lower than a predetermined maximal spatial frequency.

First claim

The invention claimed is:

1. A method for imaging a region of interest comprising:
(a) collecting input radiation from the region of interest through a selected set of a plurality of a predetermined number of aperture arrays, each array having a predetermined arrangement of apertures and collecting the input radiation during a collection time period, wherein said selected set of the aperture arrays and the corresponding collection time periods defining a total effective transmission function of the radiation collection,
(b) generating image data from the collected input radiation, said image data comprising said predetermined number of image data pieces corresponding to the input radiation collected through the aperture arrays respectively,
(c) processing the image data pieces utilizing said total effective transmission function of the radiation collection, and determining a restored image of the region of interest.

2. The method of claim 1 , wherein said set of aperture arrays is selected such that said total effective transmission function provides non-null transmission for spatial frequencies being lower than a predetermined maximal spatial frequency.

3. The method of claim 2 , wherein said corresponding collection time periods of the selected aperture arrays are selected for optimizing transmission intensities for selected spatial frequencies.

4. The method of claim 1 , wherein said minimal aperture size defining the maximal spatial frequency is selected in accordance with geometrical resolution of image detection.

5. The method of claim 1 , further comprising detecting said image data pieces using a single readout mode for all of said collection time periods of the aperture arrays, thereby integrating said image data pieces to form the image data in one scan time while selectively using the different aperture arrays.

6. The method of claim 1 , wherein said processing of the image data pieces for restoring the image of the region of interest comprises: determining a sum of intensity maps of said image data pieces and utilizing inverting the distortion effect caused by the total effective transmission function, to thereby generate said restored image data.

7. The method of claim 1 , wherein said input radiation is electromagnetic radiation in at least one of the following spectra: infra-red radiation, visible light, ultra violet radiation, x-ray radiation, and gamma radiation.

8. The method of claim 1 , wherein said processing of the image data pieces for determining the restored image data further comprises: providing a set of at least two different depth resolved effective transmission functions each corresponding to the collection of the input radiation from an object plane of the region of interest located at a different distance from said set of the aperture arrays; for each of the depth resolved effective transmission functions, determining a partially restored image data piece corresponding to the respective object plane; and generating data indicative of a three-dimensional restored image of the region of interest.

9. The method of claim 1 , wherein selection of said set of a plurality of a predetermined number of aperture arrays and the corresponding arrangement of apertures comprises: determining desired resolution for imaging and a corresponding minimal aperture dimension; determining the shape and angle of each aperture, determining a number of aperture to provide desired brightness of imaging; determining said predetermined number of arrays; determining aperture arrangement in each array to provide non-null total effective transmission function of the set of aperture arrays.

10. The method of claim 9 , wherein said determining of aperture arrangement comprises: determining aperture arrangement of a first array; determining a corresponding effective transmission function; identifying spatial frequencies for which said effective transmission function provides transmission lower than a predetermined threshold; and determining one or more additional aperture arrangement such that transmission of said one or more of the additional aperture arrangement at said identified spatial frequencies is above a predetermined threshold.

11. An imaging system comprising:
(a) a mask defining a radiation collection surface for spatial filtering of input radiation being collected, the mask comprising a plurality of apertures and being configured and operable to selectively provide a plurality of a predetermined number of spatial filtering patterns of the mask, each filtering pattern being formed by a predetermined arrangement of apertures in said collection surface;
(b) a control unit comprising: a filtering controller module; an image acquisition module and an image processing module; wherein the filtering module is configured for operating said mask to selectively collect the input radiation by different filtering patterns during selected exposure time periods; the image acquisition module is configured for receiving image data pieces corresponding to the collection of the input radiation through said filtering patterns respectively during said selected exposure time periods; and the image processing module is configured for receiving and processing the image data pieces and utilizing data indicative of a total effective transmission function of the radiation collection through said mask, and determining a restored image data of a region of interest from which the input radiation is being collected.

12. The system of claim 11 , wherein said selected a plurality of a predetermined number of spatial filtering patterns of the mask being preselected to provide said effective transmission function with non-null transmission for spatial frequencies lower than a desired predetermined maximal spatial frequency.

13. The system of claim 11 , wherein said mask being configure as a replaceable mask comprising plurality of a predetermined number of spatial filtering patterns such that the mask may be configured to selectively place a spatial filtering patterns on the radiation collection surface of the mask.

14. The system of claim 11 , wherein said mask has at least one of the following configurations: mechanical wheel comprising said two or more aperture arrays each defining a corresponding filtering pattern, and a radiation transmission modulator configured to electronically vary filtering pattern thereof.

15. The system of claim 11 , wherein said mask comprises a multiplexed arrangement of apertures corresponding to said predetermined number of spatial filtering patterns, said multiplexed arrangement of apertures comprising groups of apertures corresponding to different filtering patterns, each group of apertures comprises a wavelength selective filter configured for transmission of a predetermined wavelength range being a part of a total wavelength range for imaging.

16. The system of claim 11 , wherein the processor unit further comprising a set selection module configured to be responsive to input data comprising data about desired resolution and brightness and to determine a corresponding set of filtering patterns having non-null effective transmission function.

17. The system of claim 11 , wherein the processor unit further comprising a depth resolution pre-processing module configured to determine depth resolved effective transmission function in accordance with aperture arrangement of the set of filtering patterns.

18. The system of claim 17 , wherein the image processing module is configured and operable to determine a plurality of restored depth resolved image data pieces, eac

Assignees

• Univ Bar Ilan

Inventors

• Zalevsky Zeev
• Schwarz Moshe Arie Ariel
• Shemer Amir
• Zlotnik Alexander

Classifications

• G01T1/295

  using coded aperture devices, e.g. Fresnel zone plates (handling of radiation of particles, e.g. using diaphragms, collimators, diffraction G21K1/00) · CPC title

• G02B2207/129

  Coded aperture imaging · CPC title

• G02B30/24

  involving temporal multiplexing, e.g. using sequentially activated left and right shutters · CPC title

• H04N13/218

  using spatial multiplexing · CPC title

• G02B26/06

  for controlling the phase of light (G02B26/08 takes precedence {, measuring optical phase difference G01J9/00}) · CPC title