The present invention is directed to a laser communication transmitter and
receiver for wireless optical communication. The laser communication
transmitter uses a small diameter so correspondingly divergent beam to
provide improved bit error rates. A laser communication receiver includes
a diffractive optical element to permit detectors at different spatial
locations to detect different wavelengths of the optical signal. An
immersion lens may be employed to focus the optical signal to a spot size
smaller than the photoactive area of the detector.