Strain-Biased PLZT Input Devices (Page Composers) for Holographic Memories and Optical Data Processing

Abstract

PLZT-7/65/35 is a ferroelectric ceramic with strong electrooptic properties and memory; it is switched through transparent electrodes when mechanically strained. Matrix addressed x-y page composers for interfacing electrical and coherent optical systems are being fabricated with PLZT. Switching voltages are 50–300 V. Optical efficiencies greater than 40% have been achieved. Strains near 2.4 × 10⁻³ mm/mm permit half-wave retardation switching in 100-μ-thick plates with 80-V read-in and 190-V erase levels (60 Hz hysteresis data). A 128 × 128 element array can operate at 10⁷ bits/sec with 10-μsec switching in a row at a time mode. Half-select disturbances affect contrasts. Applications in displays are also feasible.