• Journal of Korean Ophthalmic Optics Society
• /
• v.20 no.3
• /
• pp.301-309
• /
• 2015

Purpose: This study was aimed to design new schematic eyes for presbyopia using the Navarro eye model and clinical data. Methods: We collected clinical data of eye-optical parameters of males in their age of 40, 50, and 60 from previous studies, and designed schematic eyes for presbyopia using the ZEMAX program. Results: The presbyopic process and features of the designed schematic eyes well accorded with the clinical data of previous studies. Conclusions: On the basis of the Navarro eye model, a finite schematic eyes for presbyopia were newly designed corresponding with clinical data.

• Journal of Korean Ophthalmic Optics Society
• /
• v.13 no.3
• /
• pp.61-64
• /
• 2008

Purpose: The analysis of individual eye model designed from clinical demonstration about emmetropia shows that the aberration would be changed by the wave change. Method: The model on the basis of clinical demonstration of eye ball is designed in a form of having 4 refraction surfaces and a constant refractive index. We analyzed designed twelve individual eye model into aberrations changes, as giving changes Fraunhofer lines's six wavelengths. Result: About individual eye model, change in the wavelength of the wavefront aberrations analysis using the Zernike coefficient. This data indicate that the shorter wave is, the more defocus increases and the deviation value of spherical aberration and RMS are widened. Conclusion: As quantity of defocus according to result wavelength change is shorter and shorter, inclination which is similar twelve individual eye model is bigger and bigger and individual eye model majority of cases, little change, and change is shown in part individual eye model is a significant performance degradation can be raised.

• Korean Journal of Optics and Photonics
• /
• v.15 no.3
• /
• pp.268-273
• /
• 2004

A finite model eye based on longitudinal spherical aberration is designed by an optimization method. Longitudinal spherical aberration for pupil diameter between 1 mm and 8 mm is graphed theoretically and compared with other model eyes. The chromatic dispersions are adjusted to fit experimentally observed chromatic aberration of the eye. This is a finite model eye with four a spheric refracting surfaces. It has an effective focal length of 15.842 mm. A designed reduced eye has an equivalent power of 63.12 Diopter, curvature radius of 5.281 mm, index of 1.33333, and axial length of 21.123 mm.

• Korean Journal of Optics and Photonics
• /
• v.18 no.5
• /
• pp.337-344
• /
• 2007

In recent years, there has been rapid progress in different areas of vision science, such as refractive surgical procedures, contact lenses and spectacles, and near vision. This progress requires a highly accurate modeling of optical performance of the human eyes in different accommodation states. A new novel model-eye was designed using the Navarro accommodation-dependent finite model eye. For each of the vergence distances, ocular wavefront error, accommodative response, and visual acuity were calculated. Using the new model eye ocular wavefront error, accommodation dative response, and visual acuity are calculated for six vergence stimuli, -0.17D, 1D, 2D, 3D, 4D and -5D. Also, $3^{rd}\;and\;4^{th}$ order aberrations, modulation transfer function, and visual acuity of the accommodation-dependent model eye were analyzed. These results are well-matched to anatomical, biometric, and optical realities. Our corrected accommodation-dependent model-eye may provide a more accurate way to evaluate optical transfer functions and optical performances of the human eye.

• Journal of Korean Ophthalmic Optics Society
• /
• v.9 no.2
• /
• pp.269-280
• /
• 2004

For the studying of the optical property of the human eye by using the Seidel aberrations with schematic eyes, we have used the several paraxial and fine schematic eyes. In another world, after fixing the iris ot aperture pinhole on the anterior of lens, we investigated how the surface contributions and the surface asphericity affected the optical properties of schematic eyes by using the Seidel aberration coefficients variation. Also, by analysis of dividing both a relaxed state and the accommodation state of the eye, we investigated the change of the optical properties during the change of accommodation.

• Korean Journal of Optics and Photonics
• /
• v.19 no.6
• /
• pp.439-447
• /
• 2008

There is a need for a finite schematic presbyopic eye that models vision and image quality under various conditions such as cataract or refractive surgery, as well as near vision corrections with an ophthalmic lens or contact lens. Using recently measured biometric data of presbyopic eyes, new model eyes were designed that are optically and anatomically close to real eyes. The parameters changing significantly with age were incorporated into models for four different age groups. The new model eyes have alpha angle, decentered pupil, aspheric GRIN lens and aspheric retinal surface. It is likely that the new finite presbyopic model eyes will be useful for designing visual instruments such as low vision aids, PALs, IOL and contact lenses, and for the clinical prediction of the retinal image quality of a presbyopic patient.

• Proceedings of the Korean Statistical Society Conference
• /
• 2002.11a
• /
• pp.163-168
• /
• 2002

전형적인 시공간모형은 시공간 변이도(semivariogram) 또는 공분산 함수(covariance function)를 필요로 한다. 본 논문에서는 계산하기 어렵고 현실적이지 못한 결합 공분산함수를 통한 고전적 모형 대신, 일련의 독립적인 조건분포를 이용하는 보다 현실적인 베이지안 계층모형을 이용한다. 미국 전 지역에 산재해 있는 138개 기온 관측소로부터 얻어진 61년(1920-1980) 동안의 연기온편차 자료에 시공간 베이지안 계층모형을 적용하고 순수시계열모형에서의 적합값과 제안된 모형의 적합값을 비교분석한다.

• Korean Journal of Optics and Photonics
• /
• v.13 no.3
• /
• pp.266-271
• /
• 2002

The finite schematic eye based on spherical aberration and Stiles-Crawford effect is designed by an optimization method. It consists of four aspherical surfaces. The radius of curvature, thickness, asphericity, and spherical aberration are used as constraints in the optimization process. Stiles-Crawford effect in the pupil is considered as a weighting value for optimum design. The designed schematic eye has effective focal length of 20.8169 mm, back focal length of 15.4820 mm, front focal length of -13.8528 mm, and image distance of 15.7150 mm. When the pupil diameter is 4 mm, the diameter of entrance pupil and exit pupil are 4.6919 mm and 4.2395 mm, respectively. From the data of 75 measured Korean emmetropic eyes, this finite schematic eye is designed first in Korea.

• Annual Conference on Human and Language Technology
• /
• 1991.10a
• /
• pp.219-227
• /
• 1991

본 논문에서는 정보처리에 관한 일반 모형으로 제기된 안-밖 합치도원리 모형(김정호, 1986; Kim, 1986b, 1991)을 통해서 컴퓨터 용어의 효율적인 한글화를 위한 하나의 접근방법을 제시하였다. 안-밖 합치도는 인간의 정보처리 전반에 걸쳐서 인간이 주어진 환경에서 특정 정보를 구성함에 있어서 갖는 정보처리의 좋음 혹은 쉬움을 나타내는 개념이다. 여기서 중요한 것은 안-밖 합치도가 구성할 특정 정보에 상대적이라는 점이며 안-밖 합치도를 측정할 때에는 어떤 정보에 관심이 있는가의 목적을 명백히 해야 한다. 컴퓨터 용어의 효율적 한글화는 안-밖 합치도원리 모형의 관점에서 볼 때, 특정 목적을 위하여, 만들어진 한글 컴퓨터 용어와 그 용어의 사용자 간의 안-밖 합치도를 높이고자 하는 작업이라고 할 수 있다. 본 논문에서는 컴퓨터 용어의 한글화에 있어서 고려될 수 있는 목적들을 크게 경제적 목적, 문화적 목적, 및 심미적 목적 등으로 나누어 고찰하였다. 끝으로 각 목적에 따른 실제적인 연구방법을 소개하였다.

• The Korean Journal of Applied Statistics
• /
• v.18 no.1
• /
• pp.173-182
• /
• 2005

A Bayesian threshold model is considered to analyze binary or ordered categorical traits. Gibbs sampler for making full Bayesian inferences about the category probability as well as the regression coefficients is described. The model can be regarded as an alternative to the ordered logit regression model. Numerical examples are shown to demonstrate the efficiency of the model.