• Korean Journal of Optics and Photonics
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• v.26 no.4
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• pp.217-225
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• 2015

This paper shows the best selection and combination of glass in lens design, to correct a chromatic aberration using achromatic and apochromatic conditions. Using this research result, we have designed a telecentric lens for machine vision in the full range of visible light. We obtain good optical quality in the form of a quite small RMS wavefront error of $0.057{\lambda}$ in the super-broadband wavelength range 380 nm -780 nm. This result is better than that for a common telecentric lens in the visible wavelength range 486.1-656.2 nm.

• 정보저장시스템학회:학술대회논문집
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• 2005.10a
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• pp.151-152
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• 2005

Blu-ray 디스크에서는 NA=0.85 의 높은 개구수를 채용함으로써 디스크 보호층의 두께 변동에 따른 구면수차 발생량이 매우 커지는 문제가 발생하게 된다. 따라서 디스크 두께 공차 $3{\mu}m$에서 Blu-ray 시스템의 수차 발생 허용수준을 초과한다. 그리고 Multi-layer 디스크의 경우 각 층의 간격이 $25{\mu}m$ 정도의 간격을 두고 배치되어 있어 기록층 사이에서 발생하는 구면수차의 보정이 필요하며, 종래의 기술은 보상범위가 $3{\mu}m$로 한정되어 사용이 불가능하며 또한 대물렌즈 조립공차가 엄격히 관리되어야 하는 문제점을 안고 있었다. 본 연구에서는 액정렌즈에 의한 구면수차 보정으로 이러한 문제점들을 해결하고자 하였다. 액정렌즈는 오목렌즈 액정소자와 볼록렌즈 액정소자로 구성되며 픽업 광학계 내에 조합하여 설계함으로써 Multi-layer 디스크의 두께 변동에 따라 발생하는 구면수차를 보정하고 대물렌즈 조립공차 문제를 해결할 수 있다.

• Journal of Digital Convergence
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• v.10 no.10
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• pp.301-306
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• 2012

We propose a method for accurate image acquisition in a machine vision system in the present study. The most important feature is required by the various lenses to implement real and of the same high quality image-forming optical role. The input of the machine vision system, however, is generated due to the aberration of the lens distortion. Transformation defines the relationship between the real-world coordinate system and the image coordinate system to solve these problems, a mapping function that matrix operations by calculating the distance between two coordinates to specify the exact location. Tolerance Focus Lens caused by the lens aberration correction processing to Galvanometer laser precision machining operations can be improved. Aberration of the aspheric lens has a two-dimensional shape of the curve, but the existing lens correction to linear time-consuming calibration methods by examining a large number of points the problem. How to apply the Bilinear interpolation is proposed in order to reduce the machining error that occurs due to the aberration of the lens processing equipment.

• Korean Journal of Optics and Photonics
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• v.29 no.1
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• pp.13-18
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• 2018

In this study, we present a symmetry graphical method to design an achromatic optical system composed of many lenses on an achromatic glass map. To take into account the lens spacing and the number of lenses, we use the relative ratio of paraxial ray height at each lens and the concept of an equivalent single lens. Converting an arbitrary optical system into various doublet systems, the most effective doublet is then selected to correct the color aberration, through material selection and the redistribution of the optical power. By designing a fisheye lens using this approach, an achromatic optical system is effectively obtained over the visible waveband.

• Proceedings of the Optical Society of Korea Conference
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• 2001.08a
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• pp.212-213
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• 2001

본 논문에서는 마이크로디스플레이용 광학계의 렌즈 설계와 시뮬레이션으로 구면수차, 비점수차, 왜곡, 색수차를 보정하여 설계한 광학계의 성능 평가를 소개하고자 한다.

• Proceedings of the KIEE Conference
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• 2009.07a
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• pp.1850_1851
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• 2009

본 논문에서는 스테레오 카메라를 이용한 대상물체의 3차원 정보 추출 및 가시화를 위하여 우선적으로 실시해야 하는 카메라 대한 렌즈 왜곡 보정 및 3차원 자세 보정알고리즘의 적용에 대하여 살펴보았으며, 렌즈의 왜곡 보정 부분에서는 렌즈의 구면 수차로 인한 왜곡은 각 카메라에 대하여 패턴 영상을 획득한 후 렌즈왜곡보정계수를 산출하여 왜곡 보정 실시하였다. 더불어 보정을 통하여 보다 입체감 있는 영상의 출력이 가능함을 확인할 수 있었다.

• Journal of Korean Ophthalmic Optics Society
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• v.7 no.1
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• pp.63-67
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• 2002

In this paper we analyzed the optical property after we chose the lens system to cover a wide angular field which is designed to use a established designed meniscus negative outer element. The special quality of the system is to offer a wide angular field by getting only one outer negative element and to be a compacted optical system to utilize the good point of miniaturization and light-weighturization by using two aspheric surfaces. Also, we observed the aberration correction of a aspheric as we investigated two aspheric's forms to use for a aberration correction.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2002.05a
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• pp.52-55
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• 2002

In this research, the modification method of spherical aberration, and aspherical lens shape design method were investigated. Spherical aberration affects lens's performance directly. Many studies have attempted to remove spherical aberration with a lot of methods in order to reduce the bad effect of spherical aberration. The approach to lens shape design was base on the ray tracing method. From the result, it was confirmed that ray reverse-tracing method was convenient to remove spherical aberration, and could be used very effectively and usefully for aberration-free aspherical lens design.

• Korean Journal of Optics and Photonics
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• v.13 no.4
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• pp.275-282
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• 2002

We derived analytic formulae for the correction of spherical aberration, coma, and axial color of a two-components lens system consisted of a cemented doublet and a singlet by using the thin lens approximation. The correction formulae were applied to design a telephoto lens system. We examined two kinds of glass combinations in the design, one was crown-flint-crown combination and the other was flint-crown-flint combination. We found two kinds of achromatic aplanat solutions in the crown-flint-crown combination. For the case of flint-crown-flint combination, there were also two kinds of solutions, but their configurations are not useful in practice.

• Korean Journal of Optics and Photonics
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• v.26 no.6
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• pp.299-305
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• 2015

Using Snell's Law without approximation, we analyzed focal points for parallel rays incident upon the cornea of a human eye. To calculate a ray's incident angle versus incident height for focusing on the same point, we used the ray reverse tracing method. We derived the theoretical conditions for an aspherical lens to remove the spherical aberration caused by a human eye. In this research, we held the rear surface of the lens to be spherical, for simple calculation, and calculated the lens curvature of the front surface to design an aspherical surface.