Spatial light modulators using charge-coupled-device addressing and electroabsorption effects in GaAs/AlGaAs multiple quantum wells

We describe the fabrication and performance of the first spatial light modulators (SLM’s) which combine addressing in AlGaAs charge-coupled devices (CCD’s) and electroabsorption effects in GaAs/AlGaAs multiple quantum wells (MQW’s). One-dimensional, sixteen-stage, three-phase AlGaAs CCD’s with semitransparent gates were fabricated on the surface of the SLM. The optical signal propagates normal to the surface and enters the SLM through the gates. The transmission of this signal through the MQW is then modulated according to the channel voltage of the CCD’s. The maximum contrast ratio at 847 nm was measured to be 1.45:1 for these GaAs/AlGaAs -based SLM’s.