<title>Angular selectivity independent of the writing conditions in photorefractive grating</title>

Abstract

The independent characteristic of the angular selectivity for the writing conditions was presented in photorefractive grating. In general, the incident angle of writing beam and the interaction length determine the angular selectivity of the grating. When the focused probe beam is incident on the grating, we obtain a new relation that the angular selectivity of the photorefractive grating depends on the probe beam incident conditions and is independent of the writing conditions such as writing beam incident angle, wavelength, and interaction length. These characteristics are experimentally investigated as a function of the following parameters; writing beam incident angle, probe beam width and lens focal length. In the experimental results, it has demonstrated that the control parameters are not the incident angles of writing beam but the probe beam width and focal length of the convex lens. Another property of this configuration is to have same value within large angular range that is also determined by the readout conditions.