Holographic laser scanner generating a high-resolution 2-D raster scanning pattern using a holographic scanning disc

摘要

A holographic laser scanner for producing a high-resolution raster-type 2-D laser scanning pattern within a 3-D scanning volume. The scanner comprises a housing, holographic laser scanning mechanism disposed within the housing for producing a high-resolution raster-type 2-D scanning pattern within a 3-D scanning volume. The holographic laser scanning mechanism includes a laser beam source for producing a laser beam, and a holographic scanning disc rotatable about an axis of rotation and supporting a plurality of holographic optical elements. The laser beam is directed towards the holographic laser scanning disc at an angle of incidence so that the laser beam is diffracted by the holographic optical elements and produce a raster-type 2-D laser scanning pattern for scanning code symbols within the 3-D scanning volume. A laser beam deflecting device is such as a Bragg cell, used to vary said angle of incidence varying means for varying said angle of incidence of the laser beam during rotation of the holographic scanning disc so that a high-resolution 2-D raster scanning pattern is generated from the raster-type 2-D laser scanning pattern and contained substantially within the 3-D scanning volume.