Abstract

Optimum alignment of a coherent lidar is notoriously difficult to achieve¹, particularly in compact systems designed for field operation. The correct spatial overlap and wavefront matching of signal and local oscillator beams can be especially time-consuming in systems at non-visible wavelengths (eg CO₂). Several authors have suggested re-injection of the signal into the laser oscillator to achieve automatic alignment^2-4.

© 1991 Optical Society of America