Optical transmitter-receiver

Abstract

This specification discloses a communication apparatus provided with light emitting means for generating transmission light modulated by an information signal, light receiving means for receiving modulated reception light, an optical member for reflecting one of the transmission light and the reception light and transmitting the other therethrough, a reflecting member for reflecting the transmission light emerging from the optical member to the transmission side and reflecting the reception light to the optical member, light splitting means for splitting part of the reception light obtained through the optical member, detecting means for detecting the positional state of the light obtained from the light splitting means, and driving means for rotatively driving the reflecting member about two axes in accordance with the positional state of the light detected by the detecting means. The specification further discloses an apparatus which has a lens unit having positive refractive power disposed between the light emitting means and the light splitting means and in which at least one lens constituting the lens unit is moved to thereby vary the state of the light beam.

Dependencies are inferred from the claim text.