| 摘要 |
<p>PURPOSE: To read a display having different reflectivity parts by providing one common scanning mirror, a short-range laser emitting optical device for short-range scanning operations, and a long-range laser emitting optical device. CONSTITUTION: When a trigger 12 is pulled to the position of a first detent at the time of long-range operations, a logic switch network 32 in a combinational dual scanner selects a long-range laser diode and the appropriate sighting scanning amplitude of a scanning motor is selected when the scanner is operated in a sighting mode. When the trigger 12 is pulled to the position of a second detent, the network 32 selects a laser beam for long range and a long-range scanning amplitude. At the time of short-range operations, on the other hand, an operator sets the sight of the scanner on bar codes at a short distance and actuates a trigger switch by directly pulling the trigger 12 to the position of the second detent. The network 32 selects a short-range laser diode 18 and a short-range scanning amplitude based on the shortest residence time at the position of the first detent.</p> |
