| 摘要 |
PURPOSE:To perform dimensional measurement with high accuracy regardless of the moving speed of matter, by arranging two scanning type sensors synchronized so as to be capable of respectively and simultaneously detecting two points of the matter to drive both of them. CONSTITUTION:Objective matter 11 is moved to the direction by an arrow WW by a belt conveyor 12 and the ends W1, W2 of the matter are respectively imagewise projected on image sensors 4A, 4B through optical systems 2A, 2B by light sources 3A, 3B. Both sensors are scanned and driven by the common timing signal S of a control apparatus 13 and output signals S1, S2 are inputted to the control apparatus 13 to be operated. At this time, the reference positions K1, K2 of the sensors are taken at the end parts of a matter detection range. Whereupon, the dimension Rx between both ends of the objective matter 11 comes to formula Rx=Rk1+(Ra-Rb). The control apparatus 13 measures the time Ra1... corresponding to Ra and the times Rb1... corresponding to Rb at every scanning frame and the dimension Rx of the matter 11 is calculated accord ing to the above mentioned formula. Herein, because the dimension Rx measured at every frame is negated in the effect of the moving speed of the matter 11, the measured value at every frame becomes substantially the same. |
