| 摘要 |
<p>PROBLEM TO BE SOLVED: To compensate the processing of reflected light rays from all scanning lines by providing a plurality of pattern mirrors which generate other scanning lines by damping a laser beam at a damping ratio which is different from that of a first pattern mirror. SOLUTION: An optical transceiver 14 directs a laser beam 24 to a rotor 16 and reflected light 26 from an article 28 having a bar code label 30 is projected to a detector 20. The rotor 16 contains a plurality of mirror surfaces which reflect the laser beam 24 to a pattern mirror 18 and a first attenuation pattern mirror 32 attenuates intensities of the field of the laser beam 24 and reflected light 26 to a prescribed rotor angle to a level near the intensity of the field of the light reflected from a second attenuation pattern mirror 34. The mirror 34 averages the reflected light within a prescribed intensity range so that the intensities of the lower and higher end signals can respectively become equal to a signal/noise threshold and a saturation level. Therefore, all scanning signals can be made objects to be processed.</p> |
