Abstract

We describe the construction and performance of a diffraction grating having an efficiency that can be varied by an externally applied electrical signal. The device consists, in part, of a nematic liquid-crystal layer sandwiched between a photoresist relief grating and a glass plate. Transparent electrodes are deposited on the grating and on the plate, followed by a thin polymer layer that is rubbed along the grating's grooves to ensure a planar orientation of the liquid crystal. The diffraction efficiency of the grating for monochromatic light that is linearly polarized parallel to the director can be changed by more than an order of magnitude by varying the electrode voltage. The characteristics and performance of the device are described, and its possible application to the problem of devising reconfigurable optical interconnections is discussed.

© 1990 Optical Society of America