Patent ID: 6580529
Filing Date: 2003-06-17
Classification: G02B,G03H

Abstract:
A holographic optical device, comprising:a light-transmissive substrate having two opposite major surfaces parallel to the major plane of the substrate; a first holographic optical element having a first area carried by said substrate for coupling optical waves from a light source and propagating them inside said substrate by total internal reflection; at least one second holographic optical element having a second area carried by said substrate and being laterally displaced along the major plane of the substrate, from said first holographic optical element for changing the projection on substrate plane of the propagation directions of said optical waves, and at least one third holographic optical element having a third area carried by said substrate and being laterally displaced along the major plane of the substrate from said first and second holographic elements for coupling the optical waves out of said substrate; wherein the projection of the grating vectors of said first, second and third holographic optical elements on the major surface of the substrate are oriented along three different directions, and wherein at least one of the lateral active areas of said third holographic optical element is larger than the lateral active area of said first holographic optical element.