Non-contact diameter measuring instrument

Abstract

Abstract PURPOSE:To easily measure a diameter and with a light accuracy even in case of a moving object, by projecting an image of a circular object to be measured, moving at a constant speed, to a photodetector, and calculating a diameter of the object to be measured, from a peak amplitude value of its output signal. CONSTITUTION:A circular image 4 of a moving circular object to be measured 3 is projected onto a photodetector array 1 by an optical system 2. This photodetector array 1 connects each of photodetectors of an even number and each of photodetectors of an odd number, respectively, inputs an output signal of each of them to a differential amplifier circuit 5 and obtains a signal having 2n pieces of peaks. In this state, first of all, by an arithmetic means 7, the time to the first peak of the output signal, and its amplitude are measured, and from those values, an approximate diameter is calculated. Also, by an arithmetic means 8, a peak amplitude of the output signal of the time when the circular projected image 4 is held completely on the photodetector array 1 is measured, and from its value, a diameter is calculated.

Inventors

• 👤 Shintaro Inagaki
• 👤 慎太郎 稲垣
• 👤 Akira Kobayashi
• 👤 彬 小林
• 👤 Tomio Yamaura
• 👤 山浦　富雄

Bibliographic Details