광탄성 응력측정을 위한 투과형 원형편광기 제작 및 시험

Construction and Calibration Test of a Transmission-type Circular Polariscope for Photoelastic Stress Measurement

  • 백태현 (군산대학교 기계공학부) ;
  • 김명수 (군산대학교 전자정보공학부)
  • 발행 : 2004.03.01

초록

This paper describes the construction of a circular polariscope. Generally, a circular polariscope contains four optical elements and a light source. The first element following the light source is called the linear polarizer. It converts the ordinary light into plane-polarized light. The second element is a quarter wave plate which converts the plane-polarized light into circularly polarized light. Following the quarter wave plate, a specimen made of transparent photoelastic material is located in a loading device. The second quarter wave plate is set and the last element is the analyzer. These polarizing elements, two quarter wave plates and two linear polarizing filters, were purchased from the USA. Frames and other structures for holding polarizing filters were machined and assembled to be rotated. Light box, which includes four incandescent lamps and two sodium-vapor lamps, was made. In order to proof the function of the newly built polariscope, Tardy compensation test was applied to a rectangular shaped specimen made of poly-carbonate material (PSM 1). The error of the fringe constant, which was measured by the newly built polariscope, was within 4.4 percent compared to the standard value of this material. It is possible to make a good quality of polariscope if accurate polarizing filters will be used.

키워드

참고문헌

  1. Frocht, M.M., Photoelasticity, Vol.1 and 2, John Wiley and Sons., 1967
  2. Dally, J.W. and Riley, W.F., Experimental Stress Analysis, McGraw-Hill,Inc., 1967
  3. Cloud, G. L., Optical Methods of Engineering Analysis, Optical Methods of Engineering Analysis, Cambridge University Press, 1995
  4. Theocaris, P. S. and Gdoutos, E. E., Teory of Photoelasticity, Springer-Verlag Berlin Heidelberg, 1979
  5. Photoelastic Division, Measurement Group, Inc., , Releigh, NC. 27611, 0
  6. HANGLAS Inc., 16 fl.,Youngpoong Bldg., #33 Seoring-dong, Jongro-gu, Seoul, Korea
  7. Baek, T.H., 'Digital Image Processing Technique for Photoelastic Isochromatic Fringe Sharpening', J. of the KSPE, Vol.10, No.3, pp.220-230, September, 1993
  8. Baek, T. H., Kim, M. S. and Cho, S. H., 'Simulation of Separating Isoclinincs and Isochromatics from Photoelastic Fringes of a Disk using 8-step Phase Shifting Methodology', J. of the Korean Society for Nondestructive Testing, Vol.21, No.2, pp.189-196, April 2001
  9. Baek, T. H., Kim, M. S., Cho, S. H., Morimoto, Y. and Fujigaki M., 'Digital Measurement of Isochromatics and Isoclinics in Phtoelastic Fringes through a Circular Polariscope', Proceeding of the SEM Annual Conference on Experimental Mechanics and Applied Mechanics, Society for Expermental Mechanics, Inc., pp. 125-128, 2001