Thickness variation compensation in a Fabry-Perot modulator array using a self-tuned Fabry-Perot structure

A method is presented for compensating cavity thickness variations in conventional Fabry-Perot devices through the replacement of the input mirror with a holographic mirror, resulting in a self-tuned Fabry-Perot (STFP) device. The technique is suitable for integrating large arrays of electro-optic Fabry-Perot modulators with silicon circuitry. Experimental results of a STEP modulator are presented showing cavity thickness compensation of an electrooptic 9/65/35 bulk lead lanthanum zirconate titanate crystal having thickness variations corresponding to similar to 6 Fabry-Perot fringes in a 2.5 x 2.5 mm(2) area. The compensated modulator used an in situ recorded Fe-doped LiNbO3 holographic mirror, and had a uniform backreflection over a 2.5 x 2.5 mm(2) area. (C) 1997 American Institute of Physics.