Frederick W Freyre

43902472, Jun 28, 1983

Jun 17, 1981

6/274561

Frederick W. Freyre - Wantagh NY

Hazeltine Corporation - Greenlawn NY

G02F 111

350358

Coherent light is incident upon an acousto-optical cell through which bulk acoustic waves are propagating. These acoustic waves correspond to a signal to be delayed and result from the application of the signal to a piezoelectric transducer of the cell. The waves cause periodic variations in the refractive index of the cell which interact with the coherent light. Acoustic frequency components of the propagating waves correspond to the signal frequency components and cause the cell to diffract the beam of incident coherent light and to frequency shift the diffracted beam. The relative phases of the acoustic frequency components of the acoustic waves also correspond to the phases of the frequency components of the signal to be delayed and are imparted to the respective diffracted light beams. The diffracted light is combined with undiffracted coherent light so that optical heterodyning takes place. The recombined light is focused by a Fourier transform lens onto a photomixer which detects the frequency difference between the diffracted and undiffracted light beams.

51075342, Apr 21, 1992

Sep 25, 1989

7/411968

Frederick W. Freyre - Wantagh NY

Hazeltine Corporation - Greenlawn NY

G02B 626

385 22

A flat panel display system is provided in which the pixels thereof are illuminated by optical fibers. Economy and compactness are achieved by using micromechanical light modulators to demultiplex light from a limited number of LED's to a large number of pixels. By using micromechanical light modulators incorporated in an integrated circuit, the flat panel display system is relatively economical, has low power consumption, and produces a display of very high resolution. The display also may be provided in full color.

44484941, May 15, 1984

Jun 17, 1981

6/274577

Frederick W. Freyre - Wantagh NY

Hazeltine Corporation - Commack NY

G02F 111

350358

Coherent light is incident upon an acousto-optical cell through which bulk acoustic waves are propagating. These acoustic waves correspond to a signal to be detected and cause periodic variations in the refractive index of the cell which interact with the coherent light. Acoustic frequency components of the propagating waves cause the cell to diffract beams of incident coherent light in a unique direction and to frequency shift each beam of diffracted light. The relative phases of the acoustic frequency components are also imparted to the respective diffracted light beams. Diffracted and undiffracted coherent light beams are recombined so that optical heterodyning takes place. The recombined light beams are focused by a Fourier Transform lens onto a photomixer which detects the frequency difference between the diffracted and undiffracted light beams. By detecting the recombined light beams with a photomixer array or by deflecting the position of the undiffracted light, a channelized coherent acoustic-optical receiver is achieved which may function as part of a rapidly tunable bandpass filter.

59871881, Nov 16, 1999

Dec 17, 1993

8/168406

Frederick W. Freyre - Wantagh NY

Northrop Grumman Corporation - Los Angeles CA

G06K 974

382278

An optical correlator includes at least one electrically addressable liquid crystal array, at least one LED array for generating a reference image which is modulated by changing the transmissivity of the liquid crystals in the liquid crystal array, and at least one two-dimensional large size photodiode, the photodiode receiving a modulated image from the liquid crystal array. LED and liquid crystal array are stacked together with a photodiode or an array of photodiodes with no space between, for an exceptionally simple, compact and inexpensive optical correlator structure.

44602502, Jul 17, 1984

Jun 17, 1981

6/274611

Frederick W. Freyre - Wantagh NY
Richard LaRosa - South Hempstead NY

Hazeltine Corporation - Commack NY

G02F 111

350358

Coherent light is incident upon an acousto-optical cell through which bulk acoustic waves are propagating. These acoustic waves correspond to a signal to be detected and cause periodic variations in the refractive index of the cell which interact with the coherent light. Acoustic frequency components of the propagating waves cause the cell to diffract beams of incident coherent light in a unique direction and to frequency shift each beam of diffracted light. The relative phases of the acoustic frequency components are also imparted to the respective diffracted light beams. Diffracted and undiffracted coherent light beams are recombined so that optical heterodyning takes place. The recombined light beams are focused by a Fourier Transform lens onto a photomixer which detects the frequency difference between the diffracted and undiffracted light beams. By detecting the recombined light beams with a photomixer array or, by deflecting the position of the undiffracted light or by amplitude or phase modulating the undiffracted light, a channelized coherent acousto-optical receiver is achieved which may function as part of a rapidly tunable bandpass filter.