Abstract

Tunable and narrow linewidth semiconductor lasers are useful in variety of measurement such as a spectroscopy¹ and heterodyne optical communication system. Our application is to use this tunable laser diode for absolute distance measurement. At first we have developped an external cavity in the Liftman configuration, composed by a commercial laser diode (without any special antireflexion coating). We focus our theory on the pivot axis position of the external mirror. With this theory only rotary motion is required for continuous tuning. Tunability tests show (fig1) that this laser can be tuned continuously on a frequency range of 60 GHz centered on the axial modes of the external cavity.

© 1996 IEEE