Heterodyne efficiency is discussed for a partially coherent signal and a coherent local oscillator beam. Both fileds are assumed to have Gaussian amplitude distributions. An input aperture is used to reduce the background noise. As the coherence of the signal decreases, the efficiency also decreases. However, there is a simple relation between the beam parameters and the detector dimensions to maintain optimum efficiency. The effect of the offset of the signal from the detector axis is also discussed, assuming the Gaussian probability of the deviation. In this case, the optimum parameters that give the maximum efficiency change with the average deviation.
© 1992 Optical Society of America
Original Manuscript: July 16, 1991
Published: September 1, 1992
Toshiyuki Tanaka, Mitsuo Taguchi, and Kazumasa Tanaka, "Heterodyne efficiency for a partially coherent optical signal," Appl. Opt. 31, 5391-5394 (1992)