• Journal of Korean Ophthalmic Optics Society
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• v.11 no.3
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• pp.181-185
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• 2006

The measurement of the radius of corneal curvature with keratometer was followed in 184 university students who wearing RGP contact lens and consisted of female(167), male(17) and keratoconus patients(3). Overall mean value in the radius of corneal curvature is 7.77mm, and right and left eyes is appeared the same mean value. Overall mean value in horizontal and vertical is 7.88mm and 7.65mm. Horizontal means is larger than vertical means by 0.22mm of the all female and male students. Male's mean value in the radius of corneal curvature(7.84mm) is larger than female's by 0.08mm, and right and left eyes is also the same mean value. Keratoconus patients' mean value in the radius of corneal curvature(6.86mm) is smaller than others students by 0.91mm.

• Journal of Korean Clinical Health Science
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• v.1 no.1
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• pp.1-7
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• 2013

Purpose. To analysis the prevalence of the myopia and corneal astigmatism in Korea women university students. Methods. From August 2011 to December 2012, one hundreds subjects were performed in refraction test using the Auto-Keratometry. Results. The mean age of the 100 subjects (200 eyes) was $21.23{\pm}2.34$. The mean spherical refractive power was -$1.78{\pm}1.65$(OD) and -$1.83{\pm}1.67$(OS) Diopter. The mean astigmatism power was $1.22{\pm}0.96$ (OD) and $1.27{\pm}0.91$ (OS). The mean corneal astigmatism was $1.44{\pm}0.81$(OD) and $1.55{\pm}0.93$(OS). Corneal astigmatism was between 0.25 D and 1.25 D in 67.7% of eyes, 1.25 D or higher in 27.5% eyes, and less than 0.25 D in 4.8% of eyes. Astigmatism was with the rule in 65%, against the rule in 31.5%, and oblique in 3.5%. There was a statistical significance between right eye and left eye in the spherical equivalent power(p=0.002). Also there was a statistical significance between spherical power and refractive astigmatism in OD(p=0.006) and OS(0.003) and a statistical significance between corneal astigmatism and refractive astigmatism in OS(p=0.0003). However, there was not a statistical significance between spherical power and corneal astigmatism in OD(p=0.08) and OS(0.1) and a statistical significance between corneal astigmatism and refractive astigmatism in OS(p=0.48). Conclusions. In this study, these results suggested that the analysis of the refractive myopia and corneal astigmatism can provide the visual correct and useful diagnosis information for the eyewear dispensing, contact lens fitting and corneal refraction surgery.

• Journal of the Korean Society of School Health
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• v.12 no.1
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• pp.71-84
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• 1999

This study attempts to identify the self-image of eyeglass wearers with Q-methodology. Preliminary Q-statements were collected through personal and telephone interviews and based in consultation with reference books, eyeglass wearers, an optician and an oculist. Finally, 34 Q-samples were seleted. The results were analyzed by a Q-factor with a PC QUANL Program. The self-image of eyeglass wearers were found to revolve around three types: Type 1. They feel that eyeglasses have a negative influence on image and that they uncomfortable. In addition, other people have a negative bias toward people who wear eyeglasses. As a result of these negative prejudices and inconveniences, there is a tendency to wear contact lens or have laser operations. Type 2. They feel less uncomfortable comparatively, when explained that glasses can help improve their image. When explained as a fashion accessory, negative prejudices almost disappeared. Type 3. They show a positive reaction when explained that spectacles are also used for sight protection. Howerer, they are sensitive to changes in their complexion as a result of eyeglass wear and place much importance in the design of glass frames. The significance of this study is to suggest basic data for a mediation device that improve the image of eyeglass wearers discovery and analysis of these three types.

• Journal of Korean Ophthalmic Optics Society
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• v.8 no.2
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• pp.129-134
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• 2003

A wide variety of unsaturated vinyl derivatives can be induced to undergo free-radical chain polymerization. The capability to carry out a thermodynamically feasible polymerization relies on its kinetic feasibility on whether the proceeds at a reasonable rate under a given set of reaction conditions. Initiator or promoter is often required to achieve the kinetic feasibility. Only a few unsaturated monomers including methyl methacrylate(MMA) are known to absorb light between 250 and 500 nm which is the most convenient wavelength range. Also, the polysilanes with unusual optical and electronic properties have been used as ceramic precursors, deep UV photoresists, photoconductors. The hydrosilation has been used to make many interesting types of silicon containing polymers such as copolymer, dendrimers. Bulk polymerization of monomers with different molar radio of hydrosilanes(9:1 through 1:9) were performed. A quartz test tube charged with monomer and hydrosilane was degassed and irradiated with 250 nm UV for 6 hours. The polymer was taken in toluene, precipitated in hexane, filtered off, and dried. It was found that the initiators appeared to competitively and concurrently function as both chain initiation and transfer agents in the polymerization of vinyl monomers.

• Journal of Korea Multimedia Society
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• v.15 no.6
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• pp.722-730
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• 2012

Recently, eye image information has been widely used for iris recognition or gaze detection in biometrics or human computer interaction. According as long distance camera-based system is increasing for user's convenience, the noises such as eyebrow, forehead and skin areas which can degrade the accuracy of eye detection are included in the captured image. And fast processing speed is also required in this system in addition to the high accuracy of eye detection. So, we compared the most widely used algorithms for eye detection such as AdaBoost eye detection algorithm, adaptive template matching+AdaBoost algorithm, CAMShift+AdaBoost algorithm and rapid eye detection method. And these methods were compared with images including light changes, naive eye and the cases wearing contact lens or eyeglasses in terms of accuracy and processing speed.

• Korean Journal of Materials Research
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• v.23 no.8
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• pp.453-461
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• 2013

Controlling the stick and slip motions of the contact lines in a confined geometry comprised of a spherical lens with a flat substrate is useful for manufacturing polymer ring patterns. We used a sphere on a flat geometry, by which we could control the interfaces of the solution, vapor and substrate. By this method, hundreds of concentric ring-pattern formations of a linear conjugated polymer, poly [2-methoxy-5-(2-thylhexyloxy)-1,4-phenylenevinylene] (MEH-PPV), were generated with excellent regularity over large areas after complete solvent evaporation. Subsequently, the MEH-PPV ring patterns played a role as a directed template to organize highly regular concentric rings of single-walled carbon nanotubes(SWCNTs); when a droplet of the SWCNT suspension in water was casted onto the prepared substrate, hydrophobic polymer patterns confined the water dispersed SWCNTs in between the hydrophilicized $SiO_2/Si$ substrate. As the solvent evaporated, SWCNT-rings were formed in between MEH-PPV rings with controlled density. Finally, we used a lift-off process to produce SWCNT patterns by the removal of a sacrificial polymer template with organic solvent. We also fabricated a field effect transistor using self-assembled SWCNT networks on a $SiO_2/Si$ substrate.

• Journal of Broadcast Engineering
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• v.17 no.6
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• pp.1004-1013
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• 2012

3D images and videos are required viewers to wear 3D glasses. According to the data, about half of Korean people wear glasses or contact lens and this implies 3D video viewers may have a trouble due to putting a pair of 3D glasses atop their glasses. The purpose of this study is to examine gamers' perceived characteristics, presence, and fatigue according to video gaming display (2D vs. 3D) and glasses whether wearing or not. The results show that the interaction effect of the display and wearing glasses was statistically significant in the perceived presence, and the main effect of the display was statistically significant in the perceived characteristics and fatigue.

• Parasites, Hosts and Diseases
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• v.54 no.4
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• pp.447-453
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• 2016

Acanthamoeba, a free-living amoeba, is widely distributed in the environment, water sources, soil, dust, and air. It can cause keratitis in contact lens wearers with poor hygiene and also fatal granulomatous amebic encephalitis (GAE) in immunocompromised hosts. The aim of this study was to gain some insights into the distribution and genotypes of the potentially pathogenic species of Acanthamoeba present in water sources in north of Iran. Total 43 Acanthamoeba species were isolated from 77 water samples taken from different water sources within the Mazandaran province in Northern Iran (Sari city and suburbs). Isolates were identified based on cyst and trophozoite morphological characteristics as well genetics. PCR fragments corresponding to the small-subunit 18S rRNA gene were sequenced for 20 of 43 positive isolates. The results revealed that 83.3% of sequenced isolates belonged to the T4 genotype and the rest belonged to the T2 genotype. Our results indicated that Acanthamoeba is widely distributed in Sari city. As the incidence in Iran of amoebic keratitis has increased in recent years, the exact estimation of the prevalence of this amoeba and its predominant genotype may play a crucial role in prevention of the disease. Sari city has several rivers, seashores, and natural recreational amenities, which attract visitors during the year. This is the first report of Acanthamoeba genotypes from water sources in Sari city, Mazandaran province of Iran, and the results suggest that more attention is needed to protect the visiting population and immunocompromised individuals.

• Journal of Korean Clinical Health Science
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• v.1 no.2
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• pp.31-37
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• 2013

Purpose. This study was to investigate the analysis of the central corneal thickness and anterior chamber depth of eyes in Korean Young Population using the Pentacam topography. Methods. The subjects consisted of 126 eyes from normal cornea of Korean aged 7-12($8.857{\pm}1.501$) years during 2009. The thinnest location, pachy apex, and pupil central region of the cornea thickness was measured using the Pentacam pachymetry. The anterior chamber depth of normal corneas was measured with Pentacam. Results. The thinnest location of corneal thickness was $547.413{\pm}37.893$um. The pachy apex of cornea thickness was $552.103{\pm}36.016$um. Also, the pupil center of corneal thickness was measured $552.143{\pm}36.418$um. On the other hand, the mean thickness in the central cornea was a statically significant relationship(t-test, p=0.0002) between pachy apex and thinnest zone. Also the mean thickness of the central cornea was a statically significant correlation(pearson p=0.0001) among the pupil center, pachy apex and thinnest zone. The anterior chamber depth was $3.137{\pm}0.308$mm. The mean depth in the anterior chamber of cornea was a statically relationship(t-test, p>0.05) between OD and OS. Conclusions. The results of this clinical study suggested that the analysis of the central corneal thickness and anterior chamber depth using Pentacam in Korean young population can provide the useful morphological information in diagnosis of cornea for the contact lens fitting and corneal refraction surgery.

• Journal of Korean Ophthalmic Optics Society
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• v.20 no.4
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• pp.527-536
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• 2015

Purpose: In this paper, we have dealt with problems and improvement of korean optician system. Methods: Using the relevant material of korean optician system and international optometrist system, provides the theoretical basis of the need for regulatory changes optician. Results: The people with refractive errors are increasing, 67% of refractive error test is made from optical shop and korean optician are sufficient trained, many opticians are in charge of the refractive error test at the ophthalmic hospital. We have confirmed that current law does not reflect adequately the nature of optician's work. Conclusions: Since current capacity of the Korean opticians and education system ready to provide health services for people, therefore an korean optician must redefine the law to fit the reality.