• The Korean Journal of Rheology
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• v.4 no.2
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• pp.116-126
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• 1992

본 연구에서는 형내압 파형제어 시스템, 초고속, 사출성형, 그리고 금형진공 시스템 등을 갖춘 사출 성형기를 이용하여 정밀 구면렌즈를 성형하기 위한 실험을 수행하였다. 이 러한 목적을 위해 성형공정 변수인 사출시간 충전압력 그리고 보압시간이 성형품에 미치는 영향을 중량과 곡률반경 구면 정밀도 그리고 구면오차의 간접무늬를 측정하여 연구하였다. 그결과로서 성형품의 중량(칫수)과 곡률반경에 지대한 영향력을 행사하는 변수는 충전압력 이며 사출시간과 보압시간은 곡률반경과는 무관해 보이고 중량의 증가에는 기여하지만 공정 사이클 시간을 증가시키는 문제가 지적된다. 구면정밀도 측정실험 결과 길지도 짧지도 않는 15∼20초 사이의 보압시간 4초이내의 빠른 사출시간 그리고 860kg/cm2 이상의 높은 충전압 력에서 우수한 결과를 보여주었다, 마지막으로 구면의 형상에 대한 간접무늬 측정결과는 성 형공정을 이해하는데 강력한 도구가 됨을 발견하였다.

• Korean Journal of Optics and Photonics
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• v.34 no.2
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• pp.53-60
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• 2023

We designed a catadioptric objective lens with a 0.6 numerical aperture (NA) for semiconductor inspection at 193 nm. The objective lens meets major requirements such as a spatial resolution of 200 nm and a field of view (FOV) of 0.15 mm or more. We selected a wavelength of 266 nm for autofocus based on the availability of the light source. First, we built the objective lenses of three lens groups: a focusing lens group, a field-lens group, and an NA conversion group. In particular, the NA conversion group is a group of catadioptric lenses that convert the numerical aperture of the beam focused by the prior groups to the required value, i.e., 0.6. The last design comprises 11 optical elements with root-mean-squared (RMS) wavefront aberrations less than λ/80 over the entire field of view. We also achieved the athermalization of the objective lens with focus-shift alone satisfying the performance of RMS wavefront aberration below λ/30 at a temperature range of 20 ± 1.2 ℃.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.10 no.5
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• pp.1-5
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• 2010

This paper deals with a method to measure the thickness of scale-layer, iron oxide formed on the surface of the rolling steel, using a dielectric lens antenna. The dielectric lens antenna has an independent characteristic with the frequency in the X-band and changes the spherical wave radiated from a horn antenna into a plane wave at the focusing point. Using this concept, we regard a scale-layer on the rolling steel as a dielectric-PEC(Perfect Electric Conductor) layer and apply a theoretical analysis of the normal-incident plane wave. To reduce the phase error arising from the use of the dielectric lens antenna, this paper utilizes a regression process algorithm. In comparison with the conventional iteration algorithm, the present algorithm led to a unique solution for the thickness of the scale-layer.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.39 no.10
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• pp.1021-1028
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• 2015

Subminiature lenses are currently widely used in mobile phone cameras and are usually produced by injection molding. The lens molding process has the unique feature of a runner volume that is much larger than the part volume, and this feature should be considered when determining the mold design and molding conditions. In this study, a shell-type runner was proposed as an alternative to the conventional cylindrical runner used for lens molding. An injection molding simulation was performed by applying the proposed shell runner, and the simulation results were compared with those from the cylindrical runner case. It was found that the shell runner could considerably reduce the runner cooling time with only a slight increase in the injection pressure. The effect of the runner thickness was then investigated numerically in terms of the mold filling and cooling characteristics, from which an optimal runner thickness could be determined.

• Journal of the Korean Chemical Society
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• v.54 no.4
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• pp.460-464
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• 2010

We manufactured functional contact lens materials using 2-hydroxy-4-methoxy-benzophenone, titanium(VI) isopropoxide and nanogold, nanoplatinum with UV-blocking and antimicrobial effects. Contact lens was manufactured by cast mould method. The resulting mixture was copolymerized by heating at $70^{\circ}C$ for about 40 min, at $80^{\circ}C$ for about 40 min, and finally at $100^{\circ}C$ for about 40 min. The refractive index of 1.434 ~ 1.436, water content of 35.24 ~ 36.32%, and visible transmittance of 88.3 ~ 90.8% were obtained for the contact lens materials. The polymer materials satisfied the physical properties required to make the material suitable to be applied as a functional material for ophthalmological purposes.

• Korean Journal of Optics and Photonics
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• v.16 no.3
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• pp.201-208
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• 2005

In order to realize a 3-D stereoscopic display module with alternating illumination angles, several conditions required for a lenticular lens sheet were established, and then both the lens specification and the module structure were designed. Also the performance of the stereoscopic module and its tolerance characteristics were evaluated by simulating the intensity distribution on the observation plane with a finite-ray tracing technique. From the evaluation, it was known that an intersection area between two adjacent lenses should not be filled and that the lateral mismatch between a planar liquid crystal shutter and a lens sheet should be minimized.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.12
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• pp.482-487
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• 2016

Ultra-violet rays are very harmful to eye health care. The blocking of ultra-violet rays and a reduction of optical reflection in the visible light range, which is to increase the share of transmitted light, and avoid the formation of ghost images in imaging, are important for the applications of polymer eyeglasses lenses. In this study, the high-refractive index polymer lenses, n=1.67, were fabricated by injection-molded method with the xylene diisocyanate monomer, 2,3-bis-1-propanethiol monomer, and benzotriazol UV absorber (SEESORB 709) mixture. To reduce the reflection of the polymer lens surfaces, multi-layer anti-reflection (AR) coatings were coated for both sides of the polymer lens using an E-beam evaporation system. The optical properties of the UV blocking polymer lens were characterized using a UV-visible spectrometer. The material properties of the thin films, which were composed AR coating layers, refractive index, and surface roughness, were analyzed by ellipsometry and atomic force microscopy. As a result, the fabricated polymer lens perfectly blocked ultra-violet rays below 395 nm with a blocking rate greater than 99%.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2008.11a
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• pp.525-526
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• 2008

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2012.10a
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• pp.43-44
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• 2012

본 논문에서는 도로조명용 LED 이차광학계의 제조공정에서 발행하는 형상오차를 설계에 반영하여 제작 후 형상 정밀도를 높여 궁극적으로 도로조명의 조명율을 향상시키는 방법을 제시하였다. 이를 통하여 동일한 에너지를 소모로도 더 높은 광밀도를 가질수 있는 LED2 차렌즈의 제조방법을 제시하였다.

• The Optical Journal
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• s.138
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• pp.26-28
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• 2012

(주)모노클(대표 이강수 www.monocle.co.kr)은 LCD, PDP, OLED 제조공정에서 필요로 하는 광학 Stage의 국산화와 가공기술개발에 앞장서 왔다. 현재 정밀 Quartz 및 Ceramic가공 기술을 바탕으로 Lens, Prism, Mirror & Filter Stage Glass, Micro & Macro Optical Parts, Optical Systems 등을 주력으로 생산해 오고 있다. 작은 중소기업이지만 (주)모노클이 세계시장에서 경쟁할 수 있는 제품을 생산하며 큰 역량을 발휘할 수 있었던 원동력은 꾸준히 연구개발에 투자하여 기술집약적 토대를 만들었기 때문이다.