Hsiao-Yi LEE, Hon-Fai YAU and Peir-Jyh WANG

Institute of Optical Sciences, National Central University, Chung-Li Taoyuan 320, Taiwan

(Accepted July 8, 1994)

Using the beam fanning effect in a BaTiO₃ crystal, we propose two simple set-ups to perform the function of an optical image combiner and an optical AND gate respectively. The optical image combiner combines two mutually coherent as well as mutually incoherent patterns transmitted to it separately into a single coherent pattern. This set-up can also be used as an optical OR gate. For the AND gate, the two input signals may also be mutually coherent or incoherent. Experimental results showed the response time of these two devices to range from 0.01 second to 2.5 seconds.

Key words : optical image combiner, optical OR gate, beam fanning effect, photorefractive crystal