HOLOGRAPHIC OPTICAL DEVICES

摘要

The invention provides a holographic optical device, including a light- transmissive substrate (6); a first holographic optical element (H1) carried by the substrate; at least one second holographic optical element (H2) carri ed by the substrate laterally of the first holographic optical element, and at least one third holographic optical element (H3) carried by the substrate laterally displaced from the first and second holographic optical elements; wherein the center of at least one of the first, second or third holographic optical elements is located outside a single, straight line.