| 摘要 |
The invention relates to an optical scanning apparatus for the identification of a code (11) consisting of sequential light and dark fields which respectively form modules (16, 17, 18, 19, 20, 21, 22) put together from an upwardly restricted integral multiple number of base running lengths (B1), to a module width (M), with a predetermined number of sequential modules (16, 17, 18, 19, 20) and base running lengths (B1) in the code forming a mark (25). The optical scanning apparatus guides a light bead (13), the extent of which is less than the base running length (B1) and at most only fractionally larger than the base running length (B1) of the code (11), over the modules (16, 17, 18, 19, 20, 21, 22) in sequence. By means of its light receiver (15), the light scattered back from the regions of the code (11) met by the light bead (13) is received, and a corresponding electrical signal is transmitted at the output (24). A sequence of individual pulses is formed by differentiation and rectification. A differential stage (26) with rectification and a counting stage (27) for the clock pulses generated by a clock generator (28) between two predetermined heights of the flanks of sequential individual pulses is connected to the light receiver (15). The individual counting results are applied to a memory (29) and stored there.
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