Development of (Pb,La)(Zr,Ti)O_3 Electro-Optic Thin Film for High-Speed Spatial Light Modulator

摘要

A high-speed electro-optic spatial light modulator (EOSLM) was successfully fabricated with (Pb,La)(Zr,Ti)O_3 (PLZT) electro-optic thin film. This EOSLM has a longitudinal structure, so a large electro-optic effect is necessary for low driving voltage (< 20 V). We have investigated the relationship between the orientation of polycrystalline PLZT and the electro-optic effect; we found that (111)-orientated PLZT has a large electro-optic effect, which shows a more than 0.025 refractive index change and a 183 pm/V electro-optic constant. With this PLZT film, we fabricated a prototype spatial light modulator (SLM) chip, which has 180 x 180 pixel arrays. The measured optical switching speed of this device was 7 ns, which is the highest switching speed for two-dimensional pixel array devices. Coded random data is clearly demonstrated with the prototype chip.