• Journal of Korean Ophthalmic Optics Society
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• v.10 no.4
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• pp.323-328
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• 2005

The purpose of this research was to measurement real Accommodative response amount using both eyes open-view autorefractometer. Compared each Accommodative response amount to distinction of sex, age, kind of ametropia, amount of astigmatism and kind of astigmatism. The subjects were 153 healthy men and women between the age of 20~80 years. Age comparison, 20 years 1.15D, 30 years 1.23D and above 40 years 0.60D. It was no difference between 20 to 30 years old. But, is decrescent remarkably above 40 years old. Ametropia examined by hypermetropia 1.78D, emmetropia 1.51D, low myopia 1.08D, middle myopia 0.72D, high myopia 0.643D. Myopia increased, Accommodative response amount was expose that decrease. Astigmatism examined by non astigmatism 1.13D, low astigmatism 1.12D, middle astigmatism 0.85D, high astigmatism 0.83D. Astigmatism increased, Accommodative response amount was expose that decrease. The sex and astigmatism type difference appeared with the fact that the result is not a difference.

• Proceedings of the Optical Society of Korea Conference
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• 2003.02a
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• pp.126-127
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• 2003

눈의 시력을 진단하는 도구로는 시력표, 검영기, 빔프로젝터, 자동굴절력측정기 등이 있다. 파면분석기(wavefront aberrometer)를 이용하면 눈의 굴절력 및 난시도수 외에도 광학적 고위수차(higher order aberration)를 표현하는 파면수차함수를 산출할 수 있기 때문에, 눈의 결상 능력을 정확하고 정밀하게 진단할 수 있는 가능성을 가지고 있다. 따라서 파면분석기는 현재까지 사용되고 있던 시력 또는 굴절력 계측기들의 다음 세대를 이어갈 것으로 전망하고 있다. (중략)

• Journal of Korean Ophthalmic Optics Society
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• v.11 no.3
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• pp.187-192
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• 2006

The purpose of this research was to measurement real accmmnodative response amount of emmetropia using both eyes open-view auto-refractometer. We classified 377(male 146, female 231)eyes showing good naked vision at least 1.0, with a spherical equivalent refraction of under ${\pm}0.50D$ and cylindercal refraction of under -0.75D, from 10 to 59(mean $25.8{\pm}12.4$) years into 5 groups with 10 year interval and analyzed change of the near astigmatism and accommodative response amount to distinction of age. Age comparison, total mean 1.47D, 10 years age group 1.63D, 20 years age group 1.57D, 30 years age group 1.71D, 40 years age group 0.97D, and 50 years age group 0.05D. It was no difference between 10 to 30 years age group, But it showed the decre8.se which is remarkable from above 40 years age group and it does not almost response from above 50 years age group. Sexual difference, the man appeared some highly in male(mean $26.4{\pm}12.3$ years) 1.56D m female(mean $26.4{\pm}12.3$) 1.43D. Near-astigmatism power change, mean +0.12D, 10 years age group +0.06D, 20 years age group +0.16D, 30 years age group +0.09D, 40 years age group +0.05D, and 50 years age group +0,06D. No significant difference of astigmatism powers among the an groups, but from all years age group the astigmatism power appeared more highly far-astigmatism than near-astigmatism. Near-astigmatism axis change in the far-astigmatism changes at under ${\pm}10^{\circ}$ 103 eyes, above ${\pm}10^{\circ}$ rotation clockwise direction 108 eyes, above ${\pm}10^{\circ}$ rotation counter-clockwise direction 101 eyes. It was analyzed near-astigmatism axis change.

• Journal of Korean Ophthalmic Optics Society
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• v.16 no.2
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• pp.167-170
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• 2011

Purpose: This study was tried whether expectation of astigmatism from spherical equivalent visual acuity was possible. Methods: For 54 men and women (108 eyes) corrected to emmetropia, average age of 23.3, changes of visual acuity (5m) were measured with an increasing the powers at every ${\pm}$0.25D when the (-) axis of cross cylinder is $180^{\circ}$, $90^{\circ}$, and $45^{\circ}$, respectively. Results: As the power of cross cylinder was increased, visual acuity was decreased. When the powers of cross cylinder were ${\pm}$2.50D ($180^{\circ}$ and $90^{\circ}$) and ${\pm}$2.25D ($45^{\circ}$), visual acuity was 0.05 which is the minimum measurement possible. Conclusions: The diagram on astigmatism dealing with each spherical equivalent visual acuity was able to tabulate.

• Journal of Korean Ophthalmic Optics Society
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• v.2 no.1
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• pp.61-76
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• 1997

In this paper, we found out the objective refractive errors, the full corrective refractive powers, and the prescriptions for 64 males and 36 females aged 18 to 26 years. To increase the unaided visual acuity 0.1 to the aided visual acuity 1.0 with the glasses, we needed the spherical equivalent refractive power of -3.00D for male and -2.91D for female respectively. To increase the unaided visual acuity 0.5 to the aided visual acuity 1.0 with the glasses, we needed the spherical equivalent refractive power of -0.5D for male and -1.38D for female respectively. Comparing unaided visual acuity and corrective refractive power, the more one has refractive error the less one has unaided visual acuity but these are not linear relationships. Comparing objective refractive error figures, full corrective refractive power figures and prescriptions, objective refractive error figures are the hightest, followed by full corrective refractive power figures. Prescriptions compared with the other two are lower. The cylindrical refractive powers are less than -2.50D. In this study, with the rule astigmatism is dominant over against the rule astigmatism and oblique astigmatism. The accommodation measured by push up method is 6.75D~10.04D for male and 7.50D~9.60D for female respectively.

• Journal of Korean Ophthalmic Optics Society
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• v.19 no.2
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• pp.231-237
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• 2014

Purpose: This study is research of the conditions which causes difference between the refractive power of the measurement of autorefractometer and the prescription using phoropter. Methods: Autorefractometer (SR-7000) and phoroptor (AV-9000) were used to measure 60 eyes of 30 participants who had no eye diseases and wore the corrective lens due to Ametropia. To prevent the dependence of the prescription value of the refractive power on the testers, two testers measured the refractive power of the eyes of the participants at the same measuring conditions. Results: Statistically, the prescribed values of the refractive power by two testers were not significantly different. Most of the prescribed values of the refractive power were smaller than the refractive power by autorefractometer In case of myopic eyes, the difference between refractive powers by the measurement of autorefractometer and the prescription using phoropter showed the trend of increase as the spherical refractive power became larger. The result was analyzed by the range of the different cylindrical refractive power for the myopic astigmatic eyes. In this case, the difference between refractive powers showed the trend of decrease as the cylindrical refractive power became larger. Conclusions: No difference between the prescribed value by two testers was observed. In case of myopic or myopic astigmatic eyes, the difference between refractive powers by autorefractometer and the prescription were measured to be approximately proportional to the refractive powers of ametropic eyes. As the this difference become larger for the participant who needs the lens of larger refractive power, additional caution is needed in the prescription of the refractive power of the corrective lens.

• Journal of Korean Ophthalmic Optics Society
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• v.5 no.2
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• pp.21-25
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• 2000

The old age may experienced the visual acuity decrease according to refraction abnormality and they have a inconvenient real life style on viewing condition. So that, This study can provide the accurate information on the treatment of visual acuity of a male old ages by test of eye refraction state. The test was performed the visual acuity test by the object and subject methods.and the subjects was the Korean male over 55 old age. The eye types were 0.8 % positive for emmetropia, 15.2 % for myopia, and 84 % for hyperopia, respectively. The abnormal refraction eyes were 1.3 % positive for simple myopic astigmatism, 13.9 % for compound myopic astigmatism. 3.4 % for simple hyperopia and 3.1 % for simple hyperopic astigmatism, 77.5 % for mixed astigmatism, respectively. The asix of astigmatisms were 62% positive for against-the-rule astigmatism, 6% for with-the rule astigmatism, and 32 % for oblique astigmatism, respectively. On the total myopic spherical power, the $-0.50{\leq}$spheric equivalent <-2.00 diopter was 84.3%, the $-2.00{\leq}$spherical equivalent <-6.00.diopter was 15.7%. On the total hyperopic spherical power, the $+0.50{\leq}$spheric equivalent <+2.00 diopter was 74.2%, the $+2.00{\leq}$spherical equivalent <+6.00 diopter was 24.8%, and anything over the +6.00 diopter was 1%. On the astigmatic power, the $0.5{\leq}$cylinder <1.00 diopter was 54.1%, the $1.00{\leq}$cylinder <2.00 diopter was 32.4%, and anything over the 2.00 cylinder diopter was 13.5%.

• Journal of Korean Ophthalmic Optics Society
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• v.1 no.1
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• pp.119-125
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• 1996

From 1995. 3. 20 to 1995. 4. 10 refractive errors were surveyed on the 1,197 middle and high school pupils in Dong-Du-Cuon area. On the basis of the power of the old glasses or newly examined power, we surveyed the distribution of the refractive errors according to their types, ages, heights, weights and differences between both eyes. Among 2,394 eyes examined, 1,125eyes(47%) were emmetropia, 967 eyes(40.4%) were myopic, and 302eyes(12.6%) were hyperopic. As to the distribution of refractive errors, simple myopia(42.9%) was most common, and mixed astigmatism and compound hyperopic astigmatism were below 1%, Among the types of astigmatism, 62% were with the rule, 23% were against the rule and 15% were oblique, Differences between both eyes, the left eye showed more myopic than those of right eye. The distribution of myopia according to their ages, 27.7 at age 11, 38.5% at age 12, 35.5% at age 41.5% at age 14, 37.7% at age 15, 48.3% at age 16 and 46.8% at age 17., there was a significant increase in the prevalence of the myopia but that or hyperopia decreases with increases of age.

• Journal of Korean Ophthalmic Optics Society
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• v.13 no.4
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• pp.103-107
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• 2008

Purpose: This research measured the near addition powers of presbyopia in wearing the near spectacle for the first time. Methods: We evaluated age, sex, working group, spherical power and cylindrical power and measured the power of refractive error performed the both eyes (310 eyes) of 155 subjects subjectively noncycloplegic and power of addition using the cross cylinder method. Results: There were measured the near addition powers in the range of +0.75D ~ +1.75D. In case of the average addition, they were measured with +1.06D in subjects under 43 years of age, +1.08D in 44 to 46 years, +1.23D in 47 to 49 years and +1.46D in over 50 years of age. The average age in subjects was 47.6 years old and 74 male, 81 female, 71 near sighted working group and 83 far sighted working group. Conclusions: Near addition was correlated with age, working group and cylindrical power (P<0.05, P<0.05, P<0.05).

• Journal of Korean Ophthalmic Optics Society
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• v.18 no.4
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• pp.441-447
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• 2013

Purpose: The present study was conducted to investigate the axial rotations of toric soft lens during the change of lens wearer's posture, and the relationship between its rotation and corneal astigmatism. Methods: The amount, direction, and speed of toric soft contact lens rotation were measured for 42 eyes (aged 20s) with the rule astigmatism in the straight and lying postures, and it compared between their changes according to corneal astigmatism. Results: There was no significant difference in the axial rotation of lens for the astigmatism prescription between the straight and lying postures. However, the rotation angle was significantly different according to the posture of lens wearer. Rotating directions in straight posture were nasal direction for 20 eyes and temporal direction for 22 eyes. In lying posture, lenses of most wearers were rotated to a direction of lying posture, and the initial rotating speed was very fast in initial wearing for -0.75 D toric lenses, but consistency for -1.25 D toric lenses. The rotation angle in lying posture showed significantly different according to the amount of corneal astigmatism, the lens speed was also significantly different according to the wearing time but not the amount of corneal astigmatism. Conclusions: The axial rotation of toric soft lens was different by the lens wearer's posture and its amount was the greater with the higher degree of corneal astigmatism. Thus, these factors should be considered for the development of toric lens design.