• Title/Summary/Keyword: ophthalmic lens

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Review of the plastic ophthalmic lens (플라스틱 안경렌즈에 관한 고찰)

  • Kim, Sang Yeoun
    • Journal of Korean Ophthalmic Optics Society
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    • v.1 no.1
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    • pp.65-72
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    • 1996
  • The general property of plastic ophthalmic lens has been reviewed by the optical property and polymer structure. A PMMA which is synthesized by the polymerization of monomers of two or more kinds is termed a copolymer, and the main chain composes a skeleton of molecular structure in the polymer. Refraction index of polymer was governed mainly by the polarization of molecular and was followed to increase it conspicuously as Cl, Br, and Iodine was substitude to hydrogen. Thermal dependence of refraction index of polymer show that the higher distinctive characteristic than glass material.

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Comparative Study of Physical Properties of Functional Ophthalmic Hydrogel Lens Using Photo and Thermal Polymerization

  • Kim, Duck-Hyun;Seok, Jae-Wuk;Sung, A-Young
    • Journal of Integrative Natural Science
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    • v.10 no.3
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    • pp.148-153
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    • 2017
  • In this study, HEMA, MMA, AA, and EGDMA were used as basic combinations for manufacturing hydrophilic lenses for ophthalmic applications. In addition, AIBN (thermal polymerization initiator), 2H2M (photo polymerization initiator), and 3-hydroxypyridine (additive) were used to manufacture hydrophilic ophthalmic lenses through thermal polymerization and photo polymerization before their physical properties were measured. The results showed that when ophthalmic lenses were prepared via thermal polymerization and photo polymerization using 3-hydroxypyridine as an additive, their optical and physical properties and surface structures were different in each case, but they all satisfied the physical properties required for ophthalmic lenses.

A Study of the Effects of Use upon RGP Contact Lens Surface Ultrastructure (RGP Contact Lens 표면 미세구조에 대한 사용 효과의 연구)

  • Kim, Douk-Hoon;Sung, A-Young;Crossman, Stanley
    • Journal of Korean Ophthalmic Optics Society
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    • v.11 no.1
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    • pp.71-75
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    • 2006
  • The aim of this study was to analyze the surface ultrastructure of RGP contact lenses post-use The RGP contact lenses, to investigate, were selected after one month, six months and one year of wear by the subjects. The anterior and posterior surfaces of these RGP contact lenses were inspected by a scanning electron microscope. The results were the following: 1. After one month of RGP contact lens use the anterior and posterior surfaces appeared clean and clear as originally. 2. After six months the anterior surface had several scars, dips, cracks and scratches. Upon the posterior surface appeared several foreign bodies and microorganisms. 3. After one year there was large scale damage and many foreign bodies were observed. Therefore, extended use of RGP contact lenses has shown increasing physical damage and extensive foreign body accumulation upon the ultrastructure of the lens surface.

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Epidemiological and Clinical Features of Canine Ophthalmic Diseases in Seoul from 2009 to 2013 (서울에서의 개의 안과질환에 대한 역학적 특징과 임상적인 특징에 대한 연구(2009년에서 2013년))

  • Kim, Joon-Young;Kim, Kyung-hee;Williams, David L.;Lee, Won-chang;Jeong, Soon-wuk
    • Journal of Veterinary Clinics
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    • v.32 no.3
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    • pp.235-238
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    • 2015
  • This study aimed to investigate the epidemiology of canine ophthalmic diseases in Seoul, Korea using data for new canine patients examined from January 2009 through December 2013 at an ophthalmic referral center (WooSung Animal Medical Center, Seoul). The study included 1253 dogs with an average age of 7.93 years (SD, 4.06). Shih Tzu (29.4%) was the most common breed, followed by Maltese, Yorkshire Terrier, Cocker Spaniel, and toy Poodle (P < 0.01). Lens diseases (28.3%) were the most common, followed by eyelid, corneal, retinal, and glaucomatous diseases (P < 0.01). Lens, eyelid, retinal, nasolacrimal, uveal, vitreous, and neuro-ophthalmic diseases more frequently showed a bilateral occurrence (P < 0.01) than a unilateral occurrence. In the Shih Tzu breed, corneal disease was the most frequent, followed by lens, eyelid, retinal, and glaucomatous diseases. The most frequent diseases in the Maltese breed were lens, eyelid, retinal, and corneal diseases. In the Yorkshire Terrier, Cocker Spaniel, and toy Poodle breeds, lens disease was the most common (P < 0.01). The most frequent ophthalmic patients belonged to small breeds such as Shih Tzu, Maltese, and Yorkshire Terrier. Moreover, the most common ophthalmic diseases were not traumatic diseases, but breed-inherited diseases such as lens diseases.

Opto-Physical Properties of Ophthalmic Lens Polymer Containing σ, m, p-Substituted Difluoroaniline as Additives (σ, m, p-위치로 치환된 Difluoroaniline을 첨가제로 사용한 안의료용 렌즈 고분자의 물리·광학적 특성)

  • No, Jung-Won;Sung, A-Young
    • Journal of Korean Ophthalmic Optics Society
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    • v.19 no.1
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    • pp.69-77
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    • 2014
  • Purpose: The functional ophthalmic lenses containing fluorine-substituted aniline group (2,4-difluoroaniline, 2,6-difluoroaniline, 3,4-difluoroaniline) were manufactured and the physical and optical characteristics of copolymerized ophthalmic lens were investigated. Methods: HEMA (2-hydroxyethylmethacrylate), NVP (N-vinyl pyrrolidone), MA (methacrylic acid), the cross-linker EGDMA (ethylene glycol dimethacrylate) and the initiator AIBN (azobisisobutyronitrile) were used as a basic combination and fluorine-substituted aniline group (2,4-difluoroaniline, 2,6-difluoroaniline, 3,4-difluoroaniline) were used as additives for preparing the hydrogel soft contact lenses. The hydrogel ophthalmic lens was manufactured by cast mould method and the ophthalmic lenses were stored in a 0.9% NaCl normal saline for 24 hrs. Results: The optical transmittance of the sample with addition 2,4-difluoroaniline showed that the UV-B(9.8~51.4%), UV-A(58.8~79.2%) and visible transmittance(87.0~90.4%). In the case of 2,6-difluoroaniline were measured the UV-B(80.2~83.2%), UV-A(85.8~86.4%), and visible transmittance(90.8~91.4%). Also, the optical transmittance of ophthalmic lens containing 3,4-difluoroaniline were measured the UV-B transmittance of 3.8~30.4%, UV-A transmittance of 47.8%~74.4% and the visible transmittance of 86.2~91.0% respectively. Conclusions: Based on the results of this study, 2,4-difluoroaniline and 3,4-difluoroaniline can be used effectively as additive for UV-blocking ophthalmic contact lenses.

A Study on the Method for the Local Transmittance Measurements of the Ocular Lens (안경 렌즈의 국소적 투과율 측정을 위한 방법에 관한 연구)

  • Park, Sang-Kook;Ri, Hyeong-Cheol;Youk, Do-Jin;Sung, Duk-Yong;Kang, Sung-Soo
    • Journal of Korean Ophthalmic Optics Society
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    • v.19 no.4
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    • pp.471-477
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    • 2014
  • Purpose: We have analyzed the transmittance distribution of the ocular lens using local transmittance microscope to investigate the optical homogeneity of the lens. Methods: The transmittance of the laser which is focused on the surface of the ocular lens was measured by using the photo-detector and lock-in amplifier and analyzed. Multi-coated, uncoated, and progressive lenses were analyzed. Results: In the measurement of the progressive lens and a physical stimulated lens, local transmittance microscopy analysis showed a high degree of match with the measurement results through the optical microscope. In addition, the average value of the transmittance is reduced and the standard deviation was increased in the presence of optical defects. In unstimulated lens, there are a large impact on transmittance whether the anti-reflective coating is presence or absence in both the local transmittance microscopy and general transmittance analysis. Conclusions: The distribution of the transmittance measured by local transmission microscopy were changed when the various stimulus is applied to the lenses. These analyzes by local transmission microscopy can be utilized as a way to evaluate or determine the uniformity of the coating film or lens.

Study on properties and preparations of Contact Lens Using Additive (첨가제를 이용안 콘택트렌즈의 제조와 특성에 관한 연구)

  • Sung, A-Young
    • Journal of Korean Ophthalmic Optics Society
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    • v.10 no.4
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    • pp.261-266
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    • 2005
  • Quaternary ammonium compounds(QACs) are some of the most commonly used antimicrobials. Antimicrobial polymers have been used as biomedical devices. In this Study, We synthesized new methacrylate monomers including quaternary ammonium moieties for preparation of contact lens, And also, we tested for antimicrobial activities against S. aureus, E. coli and P. aeruginosa. They showed much higher antimicrobial activities against all than the polymers of no including quaternary ammonium.

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The Variable Process of Visual Acuity for Artificial Myopia (인위적인 근시에서 시력의 회복과정)

  • Choi, Woon Sang
    • Journal of Korean Ophthalmic Optics Society
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    • v.2 no.1
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    • pp.55-60
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    • 1997
  • Numerically compares a calculation about a variable process of visual acuity for a artificial myopia with previously the tested result. The calculation is used to the value of Gullstrand's theoretical eyes and a method of geometrical optics. The theoretical eye simplified a entrance pupil and retina. Optical lens and eye changed a equivalent lens. Refractive power of a equivalent lens is converted to focal length within theoretical eyes, and this was calculated about relation of a blur circle on the retina and visual acuity.

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A Study on Optics Polishing Technology by Adaptive Tool and Eccentric Motion Mechanism (적응형 공구 및 편심 운동 방식의 광학 연마 기술에 관한 연구)

  • Lee, Ho-Cheol
    • Transactions of the Korean Society of Machine Tool Engineers
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    • v.16 no.6
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    • pp.133-139
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    • 2007
  • In this paper, optics polishing technology using adaptive tool and eccentric motion mechanism was suggested. Optics polishing can make high reflective and accurate surface. The optics polishing process based on the eccentric motion mechanism has been used to manufacture the ophthalmic lens mold. Also ophthalmic lens mold factory hold conventionally a lot of the curved polishing tools for the versatile mold curves of eye diopters and want to reduce tool numbers. Therefore, a polishing machine with adaptive airbag tool was developed and experimentally verified in view of surface roughness and form accuracy.

A Study on the Residual Astigmatism Appeared after Operating ICL Lens (ICL 렌즈 시술 후 나타나는 잔류난시에 대한 연구)

  • Kim, Dook-Hoon;Lee, Dong-Hee
    • Journal of Korean Ophthalmic Optics Society
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    • v.13 no.4
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    • pp.155-160
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    • 2008
  • Purpose: To develop a program for analyzing the condition of implanted ICL lenses in case the residual astigmatism appears after the implantation. Methods: From analyzing the measured residual astigmatism after operating ICL lens, we could induce formulas that produce the rotating angle and the corresponding MR prescription of the implanted ICL lens. Using the Delphi 6.0 language, we could develop a program by which we conveniently confirm, in the window screen visually, the rotating angle and the corresponding MR prescription of the implanted ICL lens calculated by these formulas. Results: We induced formulas that produce the rotating angle and the corresponding MR prescription of the implanted ICL lens by analyzing the measured residual astigmatism after operating ICL lens and developed a program which can analyze the condition of the implanted ICL lens. By this program we could easily analyze the condition of the implanted ICL lens. Conclusions: Judging from the results of applying this program to many clinical cases, we could conclude that this program is very effective in analyzing the condition of implanted ICL lenses.

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