Time-integrating acousto-optical processors
AssigneeThe United States of America as represented by the Director, National Security Agency
InventorTerry M. Turpin
Life of this patent
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Abstract
Disclosed are acousto-optical information processors employing a two-dimensional, time-integrating architecture. These three-product type processors are multi-purpose processors which can perform a variety of complex signal processing operations in two-dimensions, without requiring two-dimensional spatial light modulators. Typical of these processing operations are two-dimensional correlation, spectrum analysis, and cross ambiquity function processing. Some of the two-dimensional processing operations are made possible by the incorporation into a two-dimensional correlator of a distributed local oscillator, which may be implemented with mechanical-optical or electro-optical techniques. The acousto-optical processors may be easily implemented with readily available optical and acousto-optical components.
Claims16
A time-integrating optical processor comprising:
- a light beam;
- a two-dimensional time-integrating detector;
- means for modulating the light beam in a first spatial dimension, x, said x-modulating means including a first one-dimensional spatial light modulator;
- means for expanding the x-modulated beam in a second, mutually orthogonal spatial dimension, y;
- means for modulating the light beam in the second spatial dimension, said y-modulating means including a second one-dimensional spatial light modulator;
- and
- means for imaging said expanded x-modulated and said y-modulated light beams onto the detector.
A time-integrating optical processor, comprising:
- a light beam;
- means for splitting said light beam into first and second light beams;
- a first acousto-optic light modulator for modulating said first light beam with a first signal, f(t);
- first spreading means for spreading the modulated light beam from said first acousto-optic modulator in a first spatial dimension, x;
- a second one-dimensional acouto-optic light modulator for modulating said spread light beam from said first acousto-optic modulator in said first spatial dimension, x, with a second signal g(t);
- second spreading means for spreading the diffracted light from said second acousto-optic modulator in a second spatial dimension, y, orthogonal to said first spatial dimension, x;
- a scanning mirror having small linear rotations about an axis parallel to said x dimension for reflecting said second light beam from said mirror with a linearly varying frequency shift in said y dimension;
- and
- a two-dimensional time-integrating detector for detecting said light beams from said second spreading means and from said scanning mirror.
Dependencies are inferred from the claim text.