Abstract

We have previously reported resolution of 40 Ip/mm in an imaging threshold detector using a phase conjugate resonator (PCR),¹ This device, which is a combination of the conventional BaTiO₃ PCR² with the incoherent-to-coherent spatial light modulator concept^3,4, is intended to produce an output when one element of an n × n pixel array is above a preset threshold. This performance is obtained by using a separate spatially encoded erase beam to erase all transverse modes of the resonator except those of the desired element. Since the erasure is not complete, but only sufficient to keep undesirable pixels from resonating, it is necessary to avoid crosstalk, i.e., partial reflections from one element assisting the oscillation of another, for the device to operate as intended.

© 1986 Optical Society of America