PURPOSE: To read a two-dimensional bar code consisting of plural stages at a high speed with single scanning by emitting plural pulselike laser beams in time division by a multi-phase driving pulse in plural semiconductor laser beams.
CONSTITUTION: The bar codes of two stages composing a two-dimensional bar code symbol 5 by two pulse state laser beams via an optical lens system are alternately scanned for every pulse by each pulselike laser beam. The reflection light from the bar code of each stage of this two-dimensional bar code symbol 5 is received by a photodector part 6 consisting of a single photo diode and an amplifier via a rotation mirror 4. The light receiving signals photoelectrially converted and amplified in the photodetector part 6 are alternately sampled in a sample-and-hold part 7 are divided into the signal channels CH1 and CH2 corresponding to the reflection light from the bar code of each stage and are inputted in a decode part 8. In the decode part 8, an A/D conversion is performed for the outputs of the signals CH1 and CH2 and they are read as bar code information composed of two stages.
AJIKI HIROSHI
WAKAUMI HIROO
WAKAUMI HIROO
| JPS6299879A | 1987-05-09 |
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