CODED APERTURE IMAGING SYSTEM

• US 20090016481A1
• Filed: 02/06/2007
• Published: 01/15/2009
• Est. Priority Date: 02/06/2006
• Status: Active Grant

• Current Assignee: Qinetiq Limited (QinetiQ Group PLC)
• Original Assignee: Qinetiq Limited (QinetiQ Group PLC)
• Inventors: Slinger, Christopher William
• Granted Patent: US 8,035,085 B2
• Time in Patent Office: Days
• US Class Current: 378/2
• CPC Class Codes: G01T 1/295 using coded aperture devices, e.g. Fresnel zone plates handling of radiation of particles, e.g. using diaphragms, collimators, diffraction G21K1/00

Abstract

This invention relates to a coded aperture imaging system wherein a detector array is arranged to receive radiation from a scene via a coded aperture mask. The coded aperture mask provides a plurality of uncorrelated coded aperture arrays at different positions on the mask. Each distinct coded aperture array therefore passes coded information to the detector array. The intensity pattern at the detector array, which is a summation of the intensity patterns from each of the distinct coded aperture arrays, can be decoded separately for each coded aperture array to reconstruct a separate image associated with each coded aperture array. In this way the present invention teaches a coded aperture array means with multiple, simultaneous fields of view. The different fields of view can be different sizes and/or resolutions. Preferably the coded aperture mask is reconfigurable.

Claims

1. A method of coded aperture imaging comprising arranging a detector to receive radiation from a scene via a coded aperture mask wherein the coded aperture mask has a plurality of distinct coded aperture arrays at different locations of the mask.

2. A method as claimed in claim 1 wherein the coded aperture mask is provided by a reconfigurable coded aperture mask means.

3. A method as claimed in claim 1 wherein at least one of the coded aperture arrays has a different resolution to another coded aperture array.

4. A method as claimed in claim 1 wherein at least one of the coded aperture arrays has a different size to another coded aperture array.

5. A method as claimed in claim 1 wherein each coded aperture array is uncorrelated with the other coded aperture arrays.

6. A method as claimed in claim 1 wherein the different coded aperture arrays are orthogonal.

7. A method as claimed in claim 1 further comprising the step of periodically changing at least one of the position, size and resolution of at least one coded aperture array.

8. A method as claimed in claim 1 further comprising the step of periodically changing the number of coded aperture arrays.

9. A method as claimed in claim 1 further comprising the step of the step of processing the signal at the detector array to decode an image associated with each distinct coded aperture array.

10. A coded aperture imager comprising a detector arranged to receive radiation from a scene via a coded aperture mask wherein the coded aperture mask is adapted to provide a plurality of distinct coded aperture array at different locations,

11. A coded aperture imager as claimed in claim 10 wherein the coded aperture mask is a reconfigurable coded aperture mask means.

12. A coded aperture imager as claimed in claim 10 where the coded aperture mask is curved.

13. A coded aperture imager as claimed in claim 10 where the coded aperture mask is faceted.