We develop the general scanning relationships of an acousto-optic system by using both a purely geometric-optics and a physical-optics approach; each approach provides useful insights into the scanning relationships. The diffraction approach reveals that there are four basic scanning configurations: a long or short chirp scanner, either aperture or repetition-rate limited. The throughput rate for a scanner is always maximized if we use the short-chirp-scanning, repetition-rate-limited mode of operation. The maximum rate may be achieved with other configurations, but at the expense of a decrease in some of the other performance parameters. Examples are given of how these design relationships are used.

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This paper summarizes the design considerations and developmental status of a wideband holographic system breadboard designed to prove the feasibility of recording and reproducing digital data at 400 Mbits/sec and 40 Mbits/sec, respectively. The following critical system elements were investigated: multiplexer-demultiplexer electronics, linear data composer, polygonal mirror scanner, holographic recording techniques, and data readout devices. The feasibility of recording digital data in multichannel holographic form at high densities has been demonstrated on a subsystem basis.

An interferometric optical system is configured with an active feedback loop as an optical adaptive filter. The closed loop characteristics of the system are found to be sensitive to alignment and aberrations. An open loop diagnostic procedure is applied to the system to develop stability to a level supporting 30 db adaptively formed frequency rejection notches.The time delay in the closed loop signal path is found to be the limiting factor in system performance.

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