| 摘要 |
<p>PURPOSE: To attain the reading of a bar code mark positioned far from a scanning head by arranging a detecting means in order to detect an light beam in a direction almost parallel to a laser beam radiated from the scanning head. CONSTITUTION: A reflected light passes through an output window 62 first, passes through a transmission filter 90 for a read laser beam, and is made incident to a pair of photodiodes 86 and 88. Those photodiodes 86 and 88 are attached with a distance on a fringe 40, and generate an analog electric signal. When the visual field of a scanning means is about 4 inches, the visual field can be completely captured by separating the photodiodes 86 and 88 by 2 inches. The photodiodes 86 and 88 are arranged in a body part 14 in order to detect a light reaching a head 10 in a direction almost along the longitudinal direction of the body part 14 from among the lights reflected by a bar code mark. Thus, the bar code marks positioned far from the scanning head can be read.</p> |
