• Proceedings of the Optical Society of Korea Conference
• /
• 2000.02a
• /
• pp.216-217
• /
• 2000

영상매체의 발달은 고성능의 정밀한 광학소자의 발전을 요구하게 된다. 이러한 광학소자는 제작의 용이함 때문에 주로 구면소자가 많이 사용되어 왔으나 구면소자만으로 해결하기 어려운 구면수차, 왜곡수차, 비점수차 등의 요인을 극소화하고 광학소자의 소형, 경량화를 위하여 비구면 광학소자의 사용이 필요하게 되었으며 비구면 가공기술의 발전과 더불어 그 사용이 증가하고 있다. 그러나 비구면광학소자는 제작과정의 어려움과 더불어 품질평가의 어려움이 있다. 특히 급속한 기울기를 가진 면의 측정은 3차원측정기에 의한 방법이나 간섭계를 사용한 단순한 null optics 검사로는 정확도와 실험의 한계가 있다. 비구면 광학소자의 평가방법으로는 간섭계를 사용하여 기준파면과 대상파면을 비교하는 일반적인 null testing과 최근에는 CGH(computer generated hologram)로 재생된 비구면파면과 대상파면을 비교하는 방법도 많이 연구되고 있다. 본 연구에서는 일반적인 검사방법으로는 검사가 어려운 급속한 기울기를 가진 포물면(parabolic surface)에 대한 하나의 검사방법을 제시하고자 한다. (중략)

• Journal of Korean Ophthalmic Optics Society
• /
• v.17 no.4
• /
• pp.469-476
• /
• 2012

Purpose: The purpose of this study is to investigate the changes of asphericity according to diameter and direction of the cornea. Methods: The changes of asphericity according to diameter and direction of cornea is measured by using Pentacam(Oculus Co., Germany), as targeting 57 adults (average $27.0{\pm}4.8$, 20 men, 37 women) without any ophthalmic diseases, which may be effective in eyesight, and refractive surgery. Results: As diameter increases in every direction based on the corneal vertex, asphericity has attentively increased (p<0.05), and the size of asphericity in each direction from every measured diameter showed as superior > nasal > inferior > temporal. In group comparison by nearsightness and astigmatism level, asphericity measured high when nearsightness and astigmatism levels were higher, and this appears to be statistically attentive.(p<0.05). Conclusions: Asphericity of cornea significantly increased according to increase of diameter of cornea, and as measured figure or increased quantity appeared differently in all directions based on corneal vertex, so it helps to understand shape of cornea, and considered that is the part to be considered during manufacturing and fitting of RGP lenses.

• Journal of Korean Ophthalmic Optics Society
• /
• v.15 no.4
• /
• pp.355-360
• /
• 2010

Purpose: Analysis performance for spectacle lens which sales in domestic market and optimization design a spectacle lens which is corrected aberration. Methods: Measured center thickness, radius and aspherical surface coefficient for spherical and aspherical lenses which were ${\pm}$5.00D. Refractive index for every lens was 1.6 and they came from 4 different companies. I used 3 types of equipment to measure lenses. ID-F150 (Mitutoyo) : Center Thickness, FOCOVISION (SR-2, Automation Robotics) : Radius, PGI 1240S (Taylor Hobson) : Aspherical surface coefficient. Designed a lens which had 27 mm of distance from lens rear surface to center of eye, 4 mm of pupil diameter and small aberration on center vision $30^{\circ}C$. To shorten axial distance compared with the measured lens rise merits for cosmetic. Lens Design tool was CODE V (Optical Research Associates). Results: -5.00D aspherical lens had somewhat high astigmatism and distortion compared with the spherical lens. But it had a merit for cosmetic because of short axial height and decrease edge thickness. Improved a performance of distortion and ascertain merits for cosmetic due to short axial height and decrease edge thickness same as (-) lens in case of +5.00 aspherical lens. Though an optimization process front surface aspherical lens had a good performance for astigmatism and distortion and the merit for beauty compared with measured spherical lens. Conclusions: Design trend for domestic aspherical lens is decrease axial height and thickness to increase a merit for cosmetic not but increase performance of aberration. From design theory for optimization design front surface aspherical spectacle lens which has improved performance of aberration and merit for cosmetic at the same time compared with the measured lens. Expect an improved performance from design back aspherical lens compared with front aspherical lens.

• The Optical Journal
• /
• s.99
• /
• pp.25-29
• /
• 2005

현재 수출전략품목인 DVD, 디지털카메라, 휴대용 카메라폰에 요구되는 비구면Glass 광학렌즈 및 모듈 등의 핵심부품은 대부분 일본에서 수입에 의존하고 있어 대일무역적자 완화와 함께 전략산업의 안정적 기술혁신 기반구축이 요구되고 있는 실정이다. 이에 비구면 Glass 렌즈를 중심으로 하는 핵심 광학부품에 대하여 대기업을 필두로 국산화를 통한 광학기기 제품의 경쟁력 제고에 많은 노력을 기울이고 있을 뿐 아니라 비구면 Glass 렌즈의 생산을 위한 중소기업들의 시장참여가 지속적으로 이루어지고 있고, 경쟁분위기의 정착으로 향후 국내에서도 많은 기술력의 축적이 가능해지리라 전망된다.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2004.05a
• /
• pp.210-210
• /
• 2004

최근 광 디스크로부터 신호를 검출하고 기록하는 핵심장치인 장 Pick-up이 점차로 고기능화, 소형화, 경량화 되면서 광 기록장치들의 발전에 크게 기여하고 있다. 초소형, 초경량 광 Pick-up을 생산하기 위해서는 광 Pick-up의 무게와 크기에 큰 영향을 미치는 렌즈의 재료를 유리에서 플라스틱으로 전환하고, 비구면 렌즈를 사용하는 것이 필요하다. 플라스틱 비구면 렌즈를 대량 생산하기 위해서 가장 많이 사용되는 방법이 사출성형이고, 소형, 경량, 휴대기능을 강조하는 제품동향으로 인하여 플라스틱 렌즈의 주요 생산기술인 사출성형의 중요성이 날로 부각되고 있다.(중략)

• Proceedings of the Optical Society of Korea Conference
• /
• 2003.02a
• /
• pp.272-273
• /
• 2003

제조기술이 발전함에 따라 비구면을 사용한 광학계 설계에 대한 많은 연구가 보고 되고 있다. 본 연구에서는 단일렌즈에서 다양한 렌즈면 조합 중에서 성능이 가장 우수하게 나타난 비구회절면(비구면과 회절면을 동시에 적용)을 사용하여 이군렌즈에 대해 F／l.0인 대구경 광학계를 설계하였다. 사용된 검출기 사양은 픽셀 크기 45um, 픽셀 수 320$\times$240 이며, fill factor 는 무시하였다. 광학계의 유효초점거리는 171.73mm 이며, 사용한 프로그램은 ORA 사의 Code V 이다. (중략)

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.41 no.1
• /
• pp.1-12
• /
• 1996

This study was aimed to provide understanding on the eco-physiological response of barley tillers as affected by fertilizer application level. Yield and yield contribution rate of tillers were investigated with the data of field experiments in the former Wheat and Barley Research Institute of Suwon, Korea from September 1982 to July 1984. The 50％ and 100％ increased rates of fertilizer application were compared to the local recommendation, which is 120 - 90 - 70kg /ha for N-P$_2$O$_{5}$-K$_2$O, to examine tiller dynamics under diverse fertilization scheme. With the increased rates, more mainstem leaves appeared and more effective tillers resulted from C3, 4P, 41, 2P1 and 3PP. Higher number and yield of grains per plant were also observed in the increased rates, though the number of grains and grain yield per ear were slightly lower than the recommended rate. The order of yield contribution by various tillers with the recommended rate and 50％ increment was mainstem, 1, 2, 11, 3, 21, 12, 22, 4 and C, but 1 and 11 contributed more than mainstem and 3 with the 100％ increased rate.e.

• Korean Journal of Soil Science and Fertilizer
• /
• v.41 no.2
• /
• pp.75-82
• /
• 2008

In order to establish environmentally friendly phosphorus(P) and potassium(K) fertilizer application rates for rice cultivation in Korea, a field experiment was conducted in two different characterized paddy soils, higher and lower P and K content in soil from 2005 to 2006 in Suwon, Korea. Chuchong which is typical rice variety in Korea, was selected for experiment. Rice yields in base P-K fertilizer level ($30-30kg\;ha^{-1}$) and no P-K fertilizer level were 97~98% and 93~97% of standard P-K fertilizer level ($45-57kg\;ha^{-1}$), respectively. At the lower content of P and K in immatured paddy soil, the yield of no P plot was decreased by 7% compared to that of standard P-K plot. Significant difference in rice yield and yield characteristics was found neither in standard P-K fertilization plot nor in base P-K fertilization plot. There was no significant difference in P and K uptake at the harvest stage between standard P-K fertilizer plot and base P-K fertilizer plot. Phosphorus and K uptake was slightly decreased in no fertilizer plots compared to standard fertilizer plot. Phosphorus and K use efficiency of rice plant in base fertilizer plot was higher than that in standard fertilizer plot. Available phosphorus and exchangeable potassium content in soil at the harvest stage were increased in both standard and base fertilizer plot. But no significant difference of P and K content in ? was found between standard fertilizer plot and base fertilizer plot. Rice quality characteristics such as proportion of brewers rice, damaged kernel, broken rice, and content of amylose and protein were lowered in the base fertilizer plot than the standard fertilized plot, while the proportion of perfect kernel increased in the base fertilizer plot From the results, we generally recommend the base P-K fertilization ($30-30kg\;ha^{-1}$) instead of standard P-K fertilization ($45-57kg\;ha^{-1}$) for rice cultivation in Korea.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.7 no.1
• /
• pp.97-101
• /
• 1969

The experiment about the mixed sowing of two different growth type varieties of barley-Buheung and Suwon＃18-has been conducted to determine the competition effect between two varieties, and its results are as follows: 1. Buheung-long stem variety-showed higher survived ratio than Suwon＃18-short stem variety- and that tendency was significant under the high fertilized condition. 2. When tow varieties-Buheung and Suwon＃18-were sowed together, the culm length of Buheung was shorter than the single planted Buheung and that of Suwon＃18 was onger than the single planted Suwon＃18, however, the panicle length showed the opposite tendency to the culm length variation. 3. The number of panicles and the number of grains did not show any differences among the treatments. 4. In case of the single sowing, Suwon＃18 showed higher grain yield under the common fertilized condition but Buheung showed significantly increased grain yield under the heavy fertilized condition, however, in case of the mixed towing of two varieties, the grain yield was significantly increased in heavy fertilized plots than standard fertilization. 5. The competition power was significantly superior in Buheung to Suwon＃18 and this tendency was rather definite according to the fertilizer application.

• Optical Science and Technology
• /
• v.8 no.2
• /
• pp.5-13
• /
• 2004

최근 반도체, 영상정보 및 전자광학 분야 등 첨단 산업분야의 발전과 더불어 광학계의 경량화 요구가 높아짐에 따라 비구면 렌즈에 대한 수요가 급속히 증가하고 있는 실정이다. 일반적으로 비구면으로 구성된 광학계는 넓은시야와 고성능의 화상을 얻을 수 있을 뿐 아니라, 광학계를 소형, 경량화 시킬 수 있는 장점을 가지고 있어 현재, 종래의 구면 광학계가 비구면 광학계로 대체되고 있는 추세이다.(중략)