Photodiode를 이용한 길이의 精密測定에 關한 硏究

Abstract

Our investigation has been focussed on the accurate deteccting of plastic rulers, produced in Korea, through optical measurement of each space between the scales by using photodiode. This experiment has been carried on by means of the apparatus of superlow speed feeder, photodetector for light signal, level meter, amplifier, digital counter, recorder, etc. In this experiment copied nega-film of Vernier Calliper and 6 plastic rulers were moved with superlow speed feeder and the processing time in Passing 1mm was measured by six-gear digital counter(Sentinel Electronics, Inc., made) and was recorded with recorder. The results of these experiments are as follows : 1) The coverage of relative error of each space between the scales on the ruler in order of Calliper, A, B, C, D, E, F, was 0.4-0.9%, 1.3-1.8%, 1.5-1.8%, 1.4-1.8%, 1.3-1.9%, 1.2-2.1%, 1.3-2.1% 2) It was also found that the coverage of relative error measured with the recorder was 0.5-0.8%, 0.8-4.6%, 1.5-2.5%, 0.8-3.1%, 1.2-3.5%, 1.7-2.8%, 1.5-4.0%. 3) It is revealed that a photodiode can be used for accurate measurement of length.;본 연구에서는 photodiode를 이용하여 市販 國産 plaatic자의 눈금사이 간격을 光學的으로 測定해 보았다. 본 실험에서는 일제 Vernier Calliper를 nega film에 복사한 것과 6개의 Plastio자를 사용하였으며 측정기구는 超緩等速裝置와 光電檢出裝置, level meter, amplifier, 6단식 digital counter와 recorder를 사용하였다. 이 실험은 Plastic자를 초완등속장치로 이동시키면서 눈금 1㎜의 진행소요시간을 counter로 측정하면서 recorder로 기록하였다. 실험한 결과 (1) 눈금사이 간격을 counter로 측정하여 나온 상대오차의 법위는 calliper, A.B.C.D.E.F.자순으로 0.4~0.9%, 1.3~1.8%, 1.5~1.8%, 1.4~1.8~, 1.3~1.9%, 1.2~2.1%, 1.3~2.1~로 초완속등속장치에서 오는 오차를 고려한다해도 부정확함을 알 수 있다. (2) recorder로 측정하여 얻은 상대오차의 범위는 calliper A.B.C.D.E.F.자순으로 0.5~0.8%, 0.8~4.6%, 1.5~2.5%, 0.8~3.1%, 1.2~3.5%, 1.7~2.8%, 1.5~4.0%로 역시 자의 눈금사이의 간격이 부정확함을 알 수 있다. (3) photodiode는 길이의 정밀도측정에 유용하게 이용할 수 있음을 알 수 있다.