• Title/Summary/Keyword: lens centration

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Effect of the Cylindrical Fly-eye Lens's Precision on Long-axis Uniformity and Steepness of a Line Beam (실린더 잠자리 눈 렌즈의 정밀도가 선형 빔의 장축 균일도 및 경사도에 미치는 영향)

  • Lee, Seungmin;Song, Hyunsu;Woo, Hee;Kim, Daeyong;Jung, Jinho
    • Korean Journal of Optics and Photonics
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    • v.32 no.6
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    • pp.296-305
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    • 2021
  • This paper reports a study on the long axis performance of the line beam optics used in laser lift-off equipment for the OLED manufacturing process. The centration errors of the cylindrical lens are classified and defined in seven categories, and the measurement methods are presented. The cylindrical fly-eye lens is analyzed theoretically and experimentally to find the influence of the surface shape error and decentering error on the long axis performance of the line beam optics system. A future research direction is also presented to improve the long axis performance.

Synthesis of Poly(hydroxypropyl methacrylate-co-N-vinylpyrrolidone) hydrogel and its Application to the Contact Lens (Poly(hydroxypropyl methacrylate-co-N-vinylpyrrolidone) hydrogel의 합성과 콘텍트렌즈에의 응용)

  • 조종수
    • Journal of Biomedical Engineering Research
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    • v.9 no.1
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    • pp.67-72
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    • 1988
  • Poly (HPMA/NVP) hydrogel was synthesized according to the composition and the con- centration of the crosslinking agent. The swelling degree of the P(HPMA/NVP) hydrogel decreased with increasing of P(HPMA) composition and crosslinking agent. The glass transi- tion and softening temperatures of the P(HPMA/NVP) increased with increasing of P(HPMA) composition. The composition of P(HPMA/NVP) : 70/30 and the concentration of the crosslin- king agent of 0.5 wt % gave the optimum condition in the application to the contact lens. There were also adequate in the mechanical, refractive properties and in vivo test in the P(HPMA/ NVP): 70/30 system.

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The Correlation Between Corneal Eccentricity and Radius Curvature by Fitting Status of Soft Contact Lens Wearer (소프트 콘택트렌즈 착용자의 피팅 상태에 따른 각막 이심률과 곡률반경과의 상관관계)

  • Han, Sun-Hee;Kim, Bong-hwan;Park, Jun-Sung;Baek, Su-won;Kwon, Sung Jin;Kim, Eun Kyoung;Yoon, Jung Na;Choi, So Min;Heo, A Jeong;Park, Eun Hye
    • Journal of Korean Clinical Health Science
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    • v.4 no.4
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    • pp.662-670
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    • 2016
  • Purpose. Because of a recent increase in use of soft contact lens at younger ages, in the present study, the correlation between corneal eccentricity and radius of curvature and fitting types of contact lens was investigated. Methods. The study evaluated the fitting status of targets through lens centration, push-up test, dynamic lag test and static lag test of lenses usually worn by 49 men and women (98eyes) in their 20s to 30s who put on soft contact lenses. After evaluation, the subjects were classified into 3 categories by fitting status(steep, aligment and flat). The radius of corneal curvature in the naked eyes was measured by using keratometer. Moreover the corneal eccentricity in the nasal side, temporal side, superior side and inferior side was measured by using the device capable of measuring the corneal eccentricity. Results. The radius of corneal curvature and corneal eccentricity of soft lenses worn by subjects were higher in the order of steep fitting and flat fitting, and the higher average corneal curvature radius and corneal eccentricity is intend to be more steep fitting(p=0.051, p=0.052). The corneal eccentricity showed a tendency to nasal fitting type at the higher eccentricity and temporal fitting type at the smaller eccentricity, statistically significant difference was observed(p<0.05). The study showed there were low correlation that nasal and temporal side at steep fitting, superior side at normal fitting and 4side(nasal, temporal, superior, inferior) at flat fitting, therefore when the corneal eccentricity changed the radius of corneal curvature also changed. The corneal eccentricity and the radius of corneal curvature showed statistically significant difference at 4side and each fitting types(p<0.05). Conclusions. The results of this study, the fitting status, of wearer are based on radius of corneal curvature and corneal eccentricity, and if lens fitting would be done considering that, it seems to be useful in a soft contact lens prescription.

Clinical Evaluation of Prism-stabilized Toric Soft Contact Lens Fit (프리즘 안정화 디자인 토릭 소프트 콘택트렌즈 피팅에 대한 임상 평가)

  • Kim, Soo-Hyun;Kim, Jai-Min
    • Journal of Korean Ophthalmic Optics Society
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    • v.15 no.2
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    • pp.137-144
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    • 2010
  • Purpose: This study was to evaluate the clinical performance of 1-Day disposable toric soft contact lenses (TSCL) and to compare the visual performance with glasses and TSCL. Methods: In a two-week investigation of 'prism ballast' designed TSCL, occular refractions in 15 (30 eyes) healthy subjects were within the range of -2.75 D TO -8.00 D spherical power and -0.75 DC to -2.25 DC cylinderical power (with-the-rule). Subjects were assessed the clinical performance (orientation, centration, movement, tightness, rotation recovery, symptoms) of TSCL and compared binocular vision and contrast sensitivity with corrected glasses and TSCL at initial and two-week follow-up visits. Results: The prism-ballast design TSCL achieved better orientation, rotation recovery and symptoms over 2 week period. There was no statistically significant difference between spectacles and TSCL with respect to measuring binocular vision and contrast sensitivity. Conclusions: The clinical performance was good with prism-ballast design toric soft contact lenses. Evaluation of binocular vision and contrast sensitivity did not show the differences between spectacles and TSCL correction. This study suggests that TSCL wearers can be achieved similar visual performance for spectacles wearers.