| 摘要 |
A compact laser scanner for use at a counter, such as a checkout counter, to produce a scanning pattern thereabove and into which a bar code can be inserted to enable the reading of the code. A scanner is of compact height and preferably comprises a housing of a height no greater than approximately six inches and taking up an area of no greater than 150 square inches. The housing includes a top having a window through which the scanning pattern is projected and indicia for directing the location of the bar code within the scanning pattern. The scanning pattern consists of three scan lines which intersect one another in a common area to produce a star-burst pattern when projected on a plane at approximately 45 DEG to the plane of the window, while intersecting in approximately a triangular configuration when projected on a plane approximately perpendicular to the window. The scanner includes a laser tube, a rotating polygonal reflecting member and plural beam folding mirrors all disposed within the housing. The polygonal reflecting member is arranged to be mounted about a vertical axis. The laser tube is mounted laterally of the polygonal reflecting member and provides a substantially focused beam thereon. The rotation of the reflecting member causes the beam to sweep across the reflecting surfaces, which surfaces fold the beam and direct it out through the window to create the pattern. All sides of the scanner including its side walls, end walls, top and bottom walls are planar. This feature, and the compactness and light weight of the scanner enable the scanner to be positioned on any of its walls, above or below the counter, with the plane of the window at any angle with respect to the plane of the counter.
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