Abstract

Monolithic linear arrays of semiconductor injection laser devices are useful for a variety of applications including transmitting parallel channels of data along an array of fiber lightguides [1], and high-speed beam scan recording on a photoconducting material [2]. These applications, however, require that the light output powers of each laser in the array be very uniform in intensity so that each channel operates with the same signal-to-noise ratio. This places extremely stringent and often unrealistic requirements on the uniformity of lasers in the array. Alternatively, the light output power of each laser in the array can be individually monitored and used to control the laser current, thus holding the light output power constant. In this paper we demonstrate the feasibility of a very simple, low-cost technique for monitoring the light output power level of each laser in a monolithic linear array, thus making the use of a laser array practical in actual systems applications.

© 1980 Optical Society of America