Abstract

An efficient optical computing system may involve the use of a programmable logic array (PLA) where only on outputs are stored in locations addressable by the inputs. The lensless optical shadow-casting (OSC) system¹ using LEDs provides an easier and reliable means to generate logic operations. This scheme has been recently extended^2,3 to include polarized sources, masks, and encoding codes, thus increasing the design flexibility. In an OSC, each LED produces a shadow of the input overlap pattern, which along with the other similarly produced shadows give an output overlap pattern which is subsequently decoded by means of decoding masks. The original¹ and polarization-encoded^2,3 optical shadow-casting systems explored so far are designed to generate only one output at a time. We report the design of a polarization-encoded PLA device where multiple outputs are generated simultaneously for all the input pixels without switching either LEDs or mask. The proposed algorithm is thereafter employed to design an optimal multiple-output binary multiplication unit.

© 1987 Optical Society of America