Abstract

Coherent Technologies, Inc. has developed, under ARPA and Wright Laboratory funding, a lidar sensor capable of remotely detecting small motions (e.g. vibrations) of solid objects. The sensor is a coherent laser radar using a solid-state laser operating at a wavelength of 2 μm. Coherent lidar sensors capable of long-range remote vibration measurement utilizing CO₂ lasers operating at 10.6 μm have been previously reported (e.g., see references 1 and 2). Operation at the 2-μm wavelength results in improved atmospheric transmission and better spatial and velocity resolution. The 2-μm lidar instrument has demonstrated the ability to sense target velocities as small as a few hundred μm/s in measurement times of 10-100 μs. The measurement precision demonstrated agrees well with predictions of theoretical analysis and Monte Carlo simulations of the measurement process. Measurements of the motion signatures of targets located at 0.1 ~0.5 km range have been demonstrated.

© 1995 Optical Society of America