| 摘要 |
PURPOSE:To make the improvement in the accuracy of a shape detector utilizing photoelectric elements and the like by using a lens system provided with a stop mechanism of which the aperture changes in accordance with the temps. of a specimen in condensing the light from said specimen. CONSTITUTION:The light radiated from a strip plate is received in a photoelectric element group via a lens system provided with a stop mechanism of which the aperture changes in accordance with its temps. For example, if a stop mechanism 10 of which the aperture is controlled in accordance with the output of a thermometer the temps. of a strip plate 1 is disposed in front of a lens 2 in receiving the light from the strip plate in plural photoelectric elements 3 via the lens, the outputs of the photoelectric elements depend only on the width size of the strip plate in this case and are irrelevant of its temps., and therefore the size measurement with high accuracy is made possible. It is also possible to subject the outputs of the photoelectric elements to signal processing, to compare the same with a reference value W in a comparator 7 and to emit a required signal to a cutter control circuit 9 in accordance with the difference thereof. |
