• Korean Journal of Materials Research
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• v.28 no.8
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• pp.452-458
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• 2018

This research is conducted to create a functional hydrogel ophthalmic lens containing nanoparticles. Carbon nanoparticles and PEGMEMA are used as additives for the basic combination of HEMA, MA, and MMA, and the materials are copolymerized with EGDMA as the cross-linking agent and AIBN as the thermal initiator. The hydrogel lens is produced using a cast-mold method, and the materials are thermally polymerized at $100^{\circ}C$ for an hour. The polymerized lens sample is hydrated in a 0.9 % saline solution for 24 hours before the optical and physical characteristics of the lens are measured. The refractive index, water content, contact angle, light transmittance, and tensile strength are measured to evaluate the physical and optical characteristics of the hydrogel lens. The refractive index, water content, contact angle, UV-B light transmittance, UV-A light transmittance, visible light transmittance, tensile strength and breaking strength of the hydrogel lens polymer are 1.4019~1.4281, 43.05~51.18 %, $31.95{\sim}68.61^{\circ}$, 21.69~58.11 %, 35.59~84.26 %, 45.85~88.06 %, 0.1075~0.1649 kgf and 0.1520~0.2250 kgf, respectively. The results demonstrate an increase in refractive index, tensile strength and breaking strength and a decrease in contact angle and light transmittance. Furthermore, the visible light transmissibility is significantly increased at PEG 10 %. It is clear that this material can be used for high-performance ophthalmic lenses with wettability, ultraviolet ray blocking effect, and tensile strength.

• International Journal of Knowledge Content Development & Technology
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• v.10 no.2
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• pp.39-49
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• 2020

Accurate and reliable Information improves decision making, reduces costs, and saves time. The ophthalmic Libraries supply quality ophthalmic information to the ophthalmologists to serve the patients in a better way and stimulate the growth of ophthalmic field. This paper aims to study the usage of library collection, services and assistance among the Ophthalmologists - Eye Doctors in India. A survey method is used to obtain the ophthalmologists' usage of library collection, services and assistance. Through convenient sampling method, a structured questionnaire is circulated to the ophthalmologists in India and 633 ophthalmologists are responded. Among the 633 ophthalmologist, 82.15% of the ophthalmologists use the library collection - book. 73.46% of the ophthalmologists use the online data / journals. 89.73% of the ophthalmologists seek assistance to locate books/articles/documents. There exists a significant difference between the ophthalmologists use of Library Service and gender (p value 0.001**). There exists a significant difference between the ophthalmologists use of Library Assistance / help and designation category (p value 0.000**). There exists a significant difference between the ophthalmologists use of Library Assistance / help and working experience (p value 0.017**). There exists a significant difference between Library Services (p value 0.009**), Library Assistance / help (p value 0.000**) and institution type. The study results will help the ophthalmic libraries to serve the user better.

• International Journal of Advanced Culture Technology
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• v.8 no.1
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• pp.71-81
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• 2020

This study is intended to determine the effects of volunteering participation motivation on major satisfaction and continuance willingness in ophthalmic optics students. To achieve this, a survey was empirically carried out to ophthalmic optics students. The research findings showed that self-development among participation motivation factors had a significant effect on major satisfaction and continuance willingness, leisure on continuance willingness, and major satisfaction on continuance willingness in the relationship between the effects of volunteering participation motivation on continuance willingness and major satisfaction in ophthalmic optics students, respectively, adopting 3 hypotheses. On the other hand, leisure had no significant effect on major satisfaction, interpersonal exchange on major satisfaction, and interpersonal exchange on continuance willingness, respectively, rejecting 3 hypotheses. Which suggest that the high self-development willingness of college students as a factor of college volunteering participation motivation causes them to have pride and specialization in their major. Consequently, pride and specialization in major cannot only increase an understanding of personality and major, but maintain a positive attitude, leading to a long-continuous willingness, not a simple one-time service.

• Journal of Korean Ophthalmic Optics Society
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• v.3 no.1
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• pp.237-242
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• 1998

A transparent and colorless $80SiO_2-20TiO_2$(mol%) thin films on soda-lime-silica slide glass and sapphire substrate were obtained by spin-coating technique using tetraethyl orthosilicate and titanium trichloride as starting materials. The prepared film annealed at $750^{\circ}C$ showed a high transmittance and a low reflectance. For the $SiO_2-TiO_2$ films on slide glasses, a strong interaction between the sodium ion and oxygens is properbly the origin of the good stability to the high temperature and the high humidity.

• Journal of Korean Ophthalmic Optics Society
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• v.9 no.2
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• pp.251-255
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• 2004

Our research is about the measurement of the distance & near horizontal phoria by the Von Graefe test. The inspection was processed about normal 60 subjects(120eyes) aged from 20 to 30) years old by the subjective method of refraction. Among 120 eyes, the myopia is 64eyes(53%) and the emmetropia is 56eyes(47%). In the measurement of the distance horizontal phoria, we could know that the exophoria is 40%(24 subjects), the esophoria is 40%(24 subjects), and the orthophoria is 20%(12 subjects). In case of the near horizontal phoria, we could know that the exophoria is 65%(39 subjects), the esophoria is 23.3%(14 subjects), and the orthophoria is 11.7%(7 subjects).

• Journal of Korean Ophthalmic Optics Society
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• v.12 no.3
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• pp.143-149
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• 2007

We have compared and analyzed the definition of medical devices, classification, who treats, controls and sales the spectacle frames in South Korea, USA and European Union in this paper. South Korea classifies the spectacle frames as an industrial products while EU and USA regards it them as the medical devices. Sunglasses are industrial products in South Korea and EU but they are still the medical devices in USA. Assignment of spectacle frames and sunglasses as an industrial products could bring into several problems. Restricted classification of medical devices on spectacle frames and sunglasses will resolve the problem mentioned.

• Journal of Korean Ophthalmic Optics Society
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• v.4 no.2
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• pp.105-111
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• 1999

This paper presents experimental results on the electrical properties of hydrogenated amorphous carbon films(a-C:H) prepared by PECVD. DC conductance of a-C:H was measured as a function of temperatures in the range of 100 to 423K. We studied two a-C:H films: one was well explained by the Mott's Variable Range Hopping(VRH) rule, but the other sample did not follow it. However, the conduction data of second sample were well fitted to Shimakawa's Multi-Phonon Hopping(MPH) model according to which conductivity is proportional to $T^M$ with m=15-17. but, in our samples, m was 10-12. Also a-C:H showed several bias effects like relaxation of conductance, bias-dependent conductance and the change of conductance slope in 1n(${\sigma}{\sqrt{T}}$) vs. $T^{1/4}$ plot. In this study we interpret these data by bias-dependent detrapping model.

• Journal of Korean Ophthalmic Optics Society
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• v.9 no.1
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• pp.29-34
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• 2004

The aim of this thesis research is to develop equipment measuring refractive state in order to measure the general ocular function using PC-based Foucault Test(Knife Edge Test). The Image of light generated from the reflection of incident light in retina thru Knife Edge Test was photographed using a CCD camera. The resulting image was then analyzed to measure the size of pupil by measuring the diameter of reflected image. The reflection state was judged from the orientation of reflected image and the degree of abnormal reflection was confirmed by measuring the size of second image of reflection. The aberration value was calculated from the magnitude of spherical aberration obtained by comparing the brightness of second reflected image appeared in the opposite direction to the reflected image.

• Journal of Korean Ophthalmic Optics Society
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• v.8 no.2
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• pp.91-97
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• 2003

The behaviors of diamond deposition using microwave plasma chemical vapor deposition method have been studied by varying the concentration of methane in the methane - hydrogen gas mixture. The carbonization is checked from peak intensities of D($sp^3$) and G($sp^2$) peaks in Raman spectra. The hydronization and C-H bonding status in films can also be determined from FTIR results. Both the bonding strength of C-H and the ratio of $sp^3$ to $sp^2$ in bonding are found to be slightly dependent of partial pressure of $CH_4$ Judging from above results, we can conclude that the best value for partial pressure of $CH_4$ in growing process of thick films is about 13.8%.

• Journal of Korean Ophthalmic Optics Society
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• v.15 no.1
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• pp.61-66
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• 2010

Purpose: This study was performed to determine vertical fixation disparity by Fixation Disparity Card. The purpose of this study was to investigate distribution of the curve types obtained with Wesson card. Methods: Fixation disparity curves were measured on 52 subjects with the Wesson fixation disparity card. A fixation disparity curve was an x, y coordinate plot of the angular amount of fixation disparity as a function of the power of prisms through which the patient views. The fixation disparity curve variables that were used to aid in the diagnosis and management of binocular vision disorders included the x-intercept, y-intercept, curve slope and curve type. Results: Vertical fixation disparity curves by Wesson Fixation Disparity Card were very various. Conclusions: Vertiical fixation disparity curves could be used to aid in the diagnosis and prescription.