<title>Amorphous selenium liquid crystal light valve for x-ray imaging</title>

Abstract

We propose a novel x-ray image intensifier that incorporates the x-ray absorption, image formation and amplification stages with a simple, flat panel structure. The device, to be called the x ray light valve (XLV), is based on two key components physically coupled in a sandwich structure; a solid state electrostatic x-ray detector and an electro-optic light modulator. X-ray absorption in the photoconductive detector controls the state of the electro-optic modulator via creation of charge carriers and the spatial and temporal variations that they induce in the modulator potential. Since the x-ray detector is electrostatic and the photo charge is strongly coupled to the light modulator, high resolution imaging is possible. Moreover, the amplification achieved by light modulation can avoid a coupling secondary quantum sink. Thus the XLV image may be coupled to an optical sensor, e.g., charge coupled device (CCD) camera, to produce a quantum noise limited digital radiographic imaging system. We outline the structure and the operation of the XLV. We discuss the features of the XLV based image acquisition and compare the properties of the XLV based and a phosphor screen based imaging chains.