| 摘要 |
PURPOSE:To recognize the position and shape of an object without being effected with conditional changes such as illumination, by setting a binary level suitably in response to the contrast of an optical image of the object. CONSTITUTION:A reflection light from a pellet 7 irradiated with down lighting is in photoelectric conversion into, e.g. a 4-bit signal at a signal gradating device 12 consisting of an A/D converter 16. This 4-bit signal is inputted to a decoder 18 and applies the signal to an output terminal corresponding to the tone gradating of the 4-bit signal. Counters 19a-19p in the number of tone gradations provided for each tone are connected to the said output terminals. Thus, the counters store the distribution of the tone gradating. A microcomputer 21 processes the outputs of the counters and sets a binary level to comparators. |
