USA as Represented by Secretary of the Navy

Keith Bromley

Richard P Bocker

Michael A Monahan

Stanley R Clayton

Paul S Catano

Larry B Stotts

Henry J Caulfield

A electrooptic systolic array architecture performs matrix-matrix multiplication using incoherent light. The incoherent light is collimated and passed through a polarizing beamsplitter and onto a pair of optically reflecting light valves. Each of the valves has a number of cells which are continuously being updated in a clocked sequence to vary their reflectivity in acc

Matrix-matrix multiplication using an electrooptical systolic/engagement

The improved electrooptic signal processing relies upon matrix-matrix multiplication using twos complement arithmetic. A source of pulse collimated light illuminates two two-dimension spatial light modulators that operate in a reflective mode through a polarizing beamsplitter. Each of the spatial light modulators has a matrix of optically encoded information of numbers in the twos complement binary representation so that a mixed binary representation of signals is generated within the two-dimensioned photodetector array. The mixed binary representation signals are decoded to a twos complement binary representation or a decimal representation to be useful for more conventional processing techniques. The twos complement arithmetic when incorporated with the electrooptic architecture provides for a convenient means for handling bipolar numbers, avoids the need for matrix partitioning when the matrices are real and offers a means to improve accuracy over conventional optical analog techniques.

Electrooptical matrix multiplication using the twos complement

A method of compressing or expanding the frequency of signals while keeping the signals' original gross temporal relationship relies upon an electrooptical processor. An apertured mask is interposed between an area-array charge coupled device (CCD) and a light emitting diode (LED). Optical signals are emitted from the LED at a clock rate which is the same as the vertical shift rate of charge packets in the CCD. Sampling the CCD's horizontal shift register output at varying rates allows a changing of the frequencies of the optical signals or a reoccurring reversal of sequential portions. Weighting the apertured mask to define at least one Gaussian curve or triangular waveform smooths and eliminates breaks in the compressed or expanded frequencies. Sampling the CCD output at a slower rate than the vertical clock rate compresses the frequency of the representative optical signals and if the CCD output is sampled at a faster rate then the signals will be expanded or rearranged in a sequentially reoccurring order. Thus, the electrooptic processor accomplishes a compression or expansion of signals with the signal's original gross temporal relationship and does not rely upon any mechanically displaceable parts. An optional approach employs a line-array CCD detector and a bidirectionally movable apertured mask to accomplish substantially the same end results; however, this introduces the problems usually associated with mechanical devices.

Frequency compression and expansion using an electrooptical processor

Light energy data is generated in sequential interlaced field raster format y a sensor driven in azimuth to detect a panoramic scene. The light energy data is sequentially recorded together with an azimuth rate signal which is a function of the rate that the sensor is driven in azimuth. Because the sensor has been driven in azimuth, however, there is a delay in the sequential detection between first and second interlaced fields of any selected frame of the panoramic scene; consequently, when it is desired to retrieve and playback a 'stop-action' image comprised of a selected frame, compensation must be made for the delay. The recorded azimuth rate signal is used to develop a commensurate delay between the two sequential first and second interlaced fields of light energy data comprising the selected frame of light energy data which is desired to playback in 'stop-action' form. The delay period thus developed is applied to correct the delay between the first and second interlaced fields so that visual display means, such as cathode ray tube monitor, may display the 'stop-action' playback of the selected frame in a corrected form, eliminating the 'jitter' that otherwise would be visually present between first and second interlaced fields due to the sequential field rate of the raster format in which the light energy data is recorded relative to the azimuthal rate at which the sensor was driven.

Image stabilizer system for stop-action playback

An electro-optical system for performing matrix-vector multiplication includes a mask having a plurality of elements of substantially equal resolution area disposed in a matrix of M rows and N columns, each element containing recorded discrete information as defined by its degree of opacity which is representative of a predetermined mathematical value in a known matrix. A light source is positioned to illuminate the mask and has its intensity modulated as a function of the sequential values in a N X 1, vector. A multiple photo-responsive array including M elements disposed in a column is positioned to receive the light energy transmitted by the illuminated mask and generates signals at each element commensurate with the instantaneous photo energy received at its position. A suitable means which is synchronously operative with the modulation of the intensity of the light source, sequentially develops cumulative signals corresponding to the signal information contained in each column of the mask, producing a matrix-vector multiplication result.

Electro-optical system for performing matrix-vector multiplication

A multi-channel optical correlation system employs a light source to illuminate a mask having a plurality of linearly disposed channels, each of which has recorded information defined by variations in opacity along its linear length. The light source is modulated as a function of an unknown input signal. A multiple element charge coupled device having its elements arrayed in linearly disposed groups along axes parallel to the linearly disposed channels of the illuminated mask is positioned to receive the light energy transmitted by the illuminated mask for developing a charge within each such element commensurate with the photo energy received at its discrete position. A source of clock signals is periodically applied to the charge coupled device for cumulatively shifting the charges developed by each of the linearly disposed groups of discrete elements and a suitable means responsive to the resultant cumulative charge outputs of such groups indicates the group having maximum amplitude of cumulative charge thereby identifying the unknown input signal with the recorded information contained on the particular channel associated with that group.

Growing community of inventors

San Diego, CA, United States of America

Keith Bromley