• Korean Journal of Optics and Photonics
• /
• v.16 no.1
• /
• pp.56-62
• /
• 2005

Because of the wide plane and the curved field of CRT rear projection high definition television, its MTF(modulation transfer function) can't be easily measured by the usual forward testing method. Then we propose a backward testing method for the MTF so that the object plane and the image analyzer of forward testing are located at positions opposite each other. We prefer to use the backward testing method because the forward testing method has poor accuracy caused by very small numerical aperture, low spatial resolutions, and long depth of focus. We found that the backward testing method was very easy to align and had high repeatability. We confirmed the confidence of results obtained by the backward testing method in comparison with designed results.

• Korean Journal of Optics and Photonics
• /
• v.32 no.2
• /
• pp.79-85
• /
• 2021

In this paper, a study is conducted on the design of an optical system of a time-of-flight (TOF) laser distance sensor that can measure long distances by minimizing beam divergence. When measuring a long distance, the amount of light on the object's surface decreases as the distance increases, due to the diffusion angle of the laser beam, and thus the beam at the sensor also decreases, causing measurement errors. In general, a cylindrical lens is used to reduce the divergence beam angle. However, an optical system using a cylindrical lens has the problem of degraded performance due to the difficulty with assembly tolerance, as well as the problem of the increased size of the optical system, and thus the use of aspherical lenses has been increasing recently. Therefore, in this study, the optical efficiencies and assembly tolerances of optical systems using respectively a cylindrical lens and an aspherical lens are compared and analyzed.

• The Optical Journal
• /
• v.3 no.13 s.13
• /
• pp.31-36
• /
• 1991

• The Optical Journal
• /
• v.3 no.16 s.16
• /
• pp.33-38
• /
• 1991

• The Optical Journal
• /
• s.110
• /
• pp.53-57
• /
• 2007

• The Optical Journal
• /
• v.3 no.15 s.15
• /
• pp.31-36
• /
• 1991

• The Optical Journal
• /
• v.3 no.14 s.14
• /
• pp.34-38
• /
• 1991

• Optical Science and Technology
• /
• v.15 no.3
• /
• pp.7-9
• /
• 2011

• Proceedings of the Optical Society of Korea Conference
• /
• 2009.10a
• /
• pp.363-364
• /
• 2009

본 논문에서는 Z-cut Congruent $LiNbO_3$ 패브리-페롯 에탈론에서 다중빔간섭에 의한 간섭무늬의 위상변화 분석을 이용한 넓은 파장영역에서의 전기광학계수 ${r^T}_{13}$ 측정방법을 소개한다. 광통신파장 영역의 넓은 파장대역을 갖는 SLD를 광원으로 사용하여 전기광학계수의 분산을 측정하였으며 마하젠더 간섭계 구조에서 벌크형태의 샘플로 측정한 결과 값과 비교하였다.

• Korean Journal of Optics and Photonics
• /
• v.25 no.3
• /
• pp.137-141
• /
• 2014

In this study a method is proposed for measuring both the refractive index and the shape of a transparent object. The proposed method combines a digital holographic microscope with a liquid. The holograms of a sample immersed in different liquids are recorded and then the three-dimensional phase information of the sample is reconstructed numerically. In particular, we have proposed a theoretical model for determining both the refractive index and shape of a sample, and micro-corner cubes are examined experimentally.