Holographic memory read by a laser array

Abstract From the Canadian patent

A holographic memory read-out system in which multiple pages of information are angularly multiplexed onto a recording medium, either planar or volume. For read-out of the hologram a, selected one of a plurality of surface-emitting semiconductor lasers arranged in a two-dimensional array is activated. The coherent output beam is passed through a collimating lens which produces a coherent plane-wave having a direction dependent upon which laser in the array produced the output beam. The plane-wave uniformly irradiates the recording medium to thereby diffract a selected image at a set angle to an imaging apparatus.