Study on Golf Range Finder by using Biprism Theory of Keratometer

케라토미터의 바이프리즘 원리를 이용한 골프거리측정기에 관한 연구

  • 차정원 (신흥대학교 안경광학과)
  • Received : 2013.10.29
  • Accepted : 2013.12.14
  • Published : 2013.12.31


Purpose: This study was to develop golf range finder which could measure exact distance from golfer to flag by using telescope and biprism. Methods: Golf range finder was made that included telescope and biprism which could move in the telescope, and an accuracy of the range finder was analyzed in distance range 20~200 m. Results: An equation was made for measuring distance which was related at position of biprism, and we could measure distance successfully by using developed golf range finder. Biprism of 2 ${\Delta}$ was useful to measure in short distance but it had bad accuracy in long distance, and 0.5 ${\Delta}$ was more useful in long distance. Image got worse when the biprism approch to focal point of objective lens for measurement in long distance, so we developed multi-layer biprism to prevent the weak point. Conclusions: Image stabilization by biprism for measuring distance was confirmed. Even if hand was moving, the distance could be measured well by using biprism, and we could find that the induced equation for distance measurement was useful. We found that multi-layer biprism, which is was new developed, was more useful than general biprism when the biprism approched to focal point of objective lens for measurement in long distance.


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