A parallel pattern-recognition system composed of coupled-element tristable optical components is proposed. Each elemental component is an optical ring resonator in which three cells of nonlinear refractive-index material are placed between mirrors. The basic idea is derived from the symmetry-breaking instability caused by the unbalance between counterpropagating input light fields that excite the nonlinear refractive-index material (the cell) bidirectionally. Input spatial patterns composed of the arbitrary combinations of [0, 0, 0], [1, 1, 0], [0, 1, 1], and [1, 0, 1] are found to be recognized at once, yielding the capacity of ⅔ bit/cell.
© 1989 Optical Society of America
Original Manuscript: December 29, 1988
Manuscript Accepted: June 7, 1989
Published: September 1, 1989
Kenju Otsuka, "Pattern recognition with a bidirectionally coupled nonlinear-optical-element system," Opt. Lett. 14, 925-927 (1989)