Electrically steerable lasers using wide-aperture VCSELs

A wide-aperture vertical-cavity surface-emitting laser has been fabricated so as to enhance the transverse mode selection. It was found that the far f ield emission can be made to exhibit two distinct steerable beams. The lase r beams may be steered from 30 degrees away from the normal right up to nor mal emission by varying the driving current. The steering effect is a therm al effect as confirmed by transient waveform analysis. A two-channel switch was built with switching time between channels of 10 mus and crosstalk of greater than 18 dB.