Grating Light Valve

The grating light valve (GLV) is a "micro projection" technology which operates using a dynamically adjustable diffraction grating. It competes with other light valve technologies such as Digital Light Processing (DLP) and liquid crystal on silicon (LCoS) for implementation in video projector devices such as rear-projection televisions. The use of microelectromechanical systems (MEMS) in optical applications, which is known as optical MEMS or micro-opto-electro-mechanical structures (MOEMS), has enabled the possibility to combine the mechanical, electrical and optical components in very small scale.

Silicon Light Machines (SLM), in Sunnyvale CA, markets and licenses GLV technology with the capitalised trademarks Grated Light Valve and GLV, previously Grating Light Valve. The valve diffracts laser light using an array of tiny movable ribbons mounted on a silicon base. The GLV uses six ribbons as the diffraction gratings for each pixel. The alignment of the gratings is altered by electronic signals, and this displacement controls the intensity of the diffracted light in a very smooth gradation.