Patent ID: 8111404
Filing Date: 2012-02-07
Classification: G03H,G11C

Abstract:
1. A method for determining a dynamic range of a volume holographic memory of a photorefractive material comprising: creating a grating in the volume holographic material using an interference of two expanded and collimated writing laser beams; plotting a first data curve of measurements of a diffraction efficiency as a function of time of the grating by using an expanded and collimated laser beam under a Bragg phase-matching condition; plotting a second data curve of measurements of a diffraction efficiency as a function of Bragg angle mismatch under a Bragg phase-mismatching condition; determining an interaction length of the volume holographic material using the second data curve of measurements of the diffraction efficiency derived from the Bragg phase-mismatching condition; computing a recording time constant of the volume holographic material using the interaction length and the first data curve of measurements of the diffraction efficiency derived from the Bragg phase-matching condition; and computing a saturated photorefractive index of the volume holographic material using the recording time constant of the volume holographic material and two data points, including diffraction efficiency and its corresponding time, in the first data curve of measurements derived from the Bragg phase-matching condition.