Abstract

Optical spot array generators are useful for inputs to optical processing and computing systems. In this paper we demonstrate rib waveguides overlaid with many micrometer-scale grating areas which produces an array of optical beams. This beam array generator can produce a regular matrix of spots which processors such as S-SEED arrays require, as well as spot patterns in less regular shapes, such as L-shape, which are useful for other types of processors [1]. The grating outcoupler approach offers an advantage over the binary phase grating approach to spot array generation because arbitrary patterns can be implemented with the flexible arrangement of the grating areas. In addition, this technique is relatively insensitive to variations in input wavelength (e.g. mode-hopping in a semiconductor laser) and to temperature variations of the device. Finally, the highly directional nature of grating outcoupling yields beams with very low divergence, easing alignment tolerances.

© 1995 Optical Society of America