A real-time, no-moving-parts, tracking receiver that operates in the infrared region of the spectrum (λ = 905 nm) has been constructed. It optically processes the signal by means of a specially constructed holographic optical element. In one sense, this element can be thought of as an exotic optical lens with two, or four, off-axis foci. Actually, it is more than that and because of its additional holographic characteristics, it can be used for signal processing. This optical signal processing is based on the fact that the amount of light diffracted to each of the two, or four, off-axis foci is dependent on the physical position that light passes through the element. Thus, when a properly made holographic element is located at the field-lens position with detectors placed at the two, or four, image points, a real-time elec-trical tracking signal results. A number of these holographic optical elements have been fabricated, tested, and in-corporated into a tracking receiver that can track a GaAs laser illuminated target.

Date Published: 8 December 1977
PDF: 10 pages
Proc. SPIE 0118, Optical Signal and Image Processing, (8 December 1977); doi: 10.1117/12.955686

Published in SPIE Proceedings Vol. 0118:
Optical Signal and Image Processing
David P. Casasent, Editor(s)