Multiple-invariant space-variant optical processing
AssigneeThe United States of America as represented by the Secretary of the Air Force
InventorsDavid P. Casasent, Demetri Psaltis
Life of this patent
Estimating the term…
Abstract
A multiple-invariant, space variant optical processor in which two functions described by any number of separate distortion parameters can be correlated with no loss in signal-to-noise ratio of the correlation. The unknown distortion parameters can also be determined in this scheme. Experimental confirmation of the key step, determination of the non-linear phase portion of a complex optical transform can be provided.
Claims1
A multiple invariant space variant optical processing method for performing optical correlations on input signals having known multiple distortions comprising the steps of:
- (a) performing a particular coordinate transformation that is related to one of said multiple distortions on the signal having multiple distortions;
- (b) performing an optical Fourier transformation on the coordinate transformed signal;
- (c) extracting the linear part of the phase of the Fourier transformed signal for said one of said multiple distortions;
- (d) repeating the steps of performing a coordinate transformation, performing an optical Fourier transformation and extracting the linear part of the phase of the Fourier transformed signal on the resultant signal from the extracting step for each of said known multiple distortions;
- and
- (e) correlating the resultant signal, free from said known multiple distortions, with an undistorted reference signal.
Dependencies are inferred from the claim text.