• The Journal of the Acoustical Society of Korea
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• v.18 no.2
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• pp.66-76
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• 1999

This paper proposes that can take at high speed the information of binocular disparity with moving translational and forward stereo camera to the extent that does not occur the problem of a correspondence point. It shows that in case of stereo vision with translational motion, can take the information of binocular disparity being devoid of error and putting high confidence in, and that in case of stereo vision with forward motion, can take the horizontal component which can not be detected in common stereo vision. Besides, the stereo vision can be done at high speed due to being bright and small a correspondence point comparing not to do, because a correspondence between right and left images is previously limited. But there are problem that a resonable information of binocular disparity can not be taken, if the vicinity of center of image is in accord with the region of occlusion in stereo vision with forward motion.

• Korean Journal of Cognitive Science
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• v.14 no.1
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• pp.17-28
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• 2003

In order to provide natural images with a specified depth through three-dimensional display system, the stereo images should be similar to those projected from real environment as much as possible. Even when two persons see an identical scene, the binocular Parallax between two images of an object varies as a function of one's inter-pupilary distance (IPD). In this study, we investigated whether individual differences, such as IPD and accommodative vergence, would affect the perception of three dimensional scene provided by stereo-images. Results showed that a person's IPD is correlated with the limit of screen and binocular parallax for single vision, and affects the perceived depth of an object on fixation. More specifically, with longer IPD the limit of screen and binocular parallax for single vision is decreased, and the perceived depth is reduced. These results suggest that the screen and binocular parallax of an object should be calibrated with regard to users IPD to provide natural stereo-images with a specified depth and to Prevent double vision.

• Journal of Korean Ophthalmic Optics Society
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• v.10 no.1
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• pp.41-46
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• 2005

The aim of the study was performed the wave analysis of P-VEP on the normal monocular vision and amblyopia in binocular. The P-VEP of three channels were recorded by the Nicolet system. Five adults (three males, two females, mean=22 years, range=19 to 24) subjects were recorded The subjects were researched the history including the systemic health, medication, genetics, allergy and ocular disease. Visual acuity and stereopsis were recorded for each subject monocularly and binocularly. Also subjects viewed the P-VEP stimulus both monocularly and binocularly through the corrected visual acuity during the VEP were recorded. The results of study suggest that the visual acuity of binocularly is better than with monocularly and the stereopsis was about over 140 sec. On the other hand, the analysis of P-VEP suggest that the amplitude of wave is larger when the monocular eye receives the P-VEP stimulus compared with the binocular eye. However the amplitude of wave in amblyopia had more smaller than the normal monocular The latency period of P-VEP was similar to results between the normal eye and binocular vision. But the amblyopia was a long period compared with the normal monocular and binocular vision. In conclusion, this study indicated that the visual acuity of binocularly have a better than the normal monocular vision, But in the P-VEP test, the amplitude of wave on normal monocularly vision appears to be better through the binocularly. But the amblyopia appeared the low amplitude wave of P-VEP and decreased the visual acuity.

• Journal of Korean Ophthalmic Optics Society
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• v.16 no.2
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• pp.171-177
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• 2011

Purpose: The purpose of this study was to investigate the relationships between reading ability and binocular functions, based on self tests through surveys. The possibility of the reading ability tests used in this study as a tool on the determination about vision efficiency was also evaluated. Methods: Through reading ability tests about 138 university students, 72 students (52.2%) of them were first selected. Through self tests about dyslexia and light sensitivity, 38 students (52.7%) of the first selected students were secondly selected, whose extents are more than 3. Binocular tests were carried out about three groups (high, middle, low) of these secondly selected students. Tests about NPCs, distance and near phoria, amplitude of accommodation, fusional vergence, AC/A ratio, accommodative facility, and vergence facility were performed as binocular tests. Results: NPCs were closest to eyes at high groups. Fusional vergence, AC/A ratio, accommodative facility, and vergence facility of high group showed higher than other groups. The phoria at middle group showed higher than other groups. Conclusions: We found that reading ability and some of binocular functions were closely related. Therefore, vision training, associated with insufficiencies of binocular functions, is expected to improve reading ability.

• Journal of Korean Ophthalmic Optics Society
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• v.10 no.1
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• pp.71-82
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• 2005

The aim of this study was to provide fundamental data for the factors influencing the asthenopia of emmetropia with phoria and alleviation of asthenopia. A total of 348 subjects, aged between 19 and 30 years old, who had no strabismus, an eye trouble or whole body disease, were examined using corrected visual acuity, corrected diopter, stereopsis and suppression tests from September of 2002 to September of 2004. We excluded 21 subjects for the following reasons: if they had an amblyopia affecting binocular vision or inaccurate data. After these exclusions, 327 subjects remained. We then individually measured the refractive error correction, pupillary distance, optical center distance, phoria, convergence, accommodation and the AC/A as well as the asthenopia during binocular vision using a questionnaire. After analysis of factors affecting asthenopia, we also examined the reductive effect of a prism on the asthenopia in subjects who had asthenopia. To determine the factors affecting asthenopia during binocular vision, statistic analyses were carried out using the Chi-square test and the multivariate Logistic regression model. The results of this study were as follow. For asthenopia during near binocular vision of emmetropia with phoria, in case of the lower the accommodation and convergence, a significantly higher rate of asthenopia was observed (p<0.001). When the AC/A is lower, the higher the rate of asthenopia was observed but not significantly and there was no association between phoria and asthenopia. When the multivariate logistic regression model was used to determine factors affecting binocular vision of emmetropia with phoria, in case of the lower accommodation and convergence, a significantly higher rate of asthenopia was observed. when the phoria is esophoria or higher exophoria, or when the AC/A is lower than normal, the higher the rate of asthenopia was observed but not significantly and there was no association between phoria. AC/A and asthenopia. Therefore accommodation and convergence could be predictive factors for asthenopia during near distance binocular vision. Prism was used among' subjects who had asthenopia during near distance binocular vision, the symptom of asthenopia was eased up to 74.2% in emmetropia with phoria.

• Journal of Korean Ophthalmic Optics Society
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• v.16 no.3
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• pp.345-350
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• 2011

Purpose: This was a study of the effects of the vision training on binocular function and sensory anomaly for intermittent exotropia and recurrent intermittent exotropia patients. Mehtods: The change was examined weekly at the clinic during the 8 week vision training. The sample group of 17 patients, intermittent exotropia and recurrent intermittent exotropia patients without amblyopia, were chosen from the patients with the short and the long-distance deviation angle p=0.558 and p=0.338, and also greater than 10${\Delta}$, respectively. Results: The longdistance deviation angle was reduced by 67.9(${\pm}$32.7)%, and the short-distance deviation angle by 75.4(${\pm}$32.9)% after the vision training. There is an improvement on the binocular function and sensory anomaly according to the fusion reverse and Worth 4 dot tests. Conclusions: This study shows that the vision training is effective for phoria, function and sensory anomalyon of the intermittent extropia and recurrent intermittent exotropia patients.

• Journal of the Institute of Convergence Signal Processing
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• v.6 no.3
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• pp.112-119
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• 2005

In this paper, a model of neural circuit was proposed, which abstracts the depth information in two images gotten from right and left retinas. The proposed neural circuit corresponds to binocular stereo vision based on psychologic and physiological knowledge, and we examine a restoration method of three-dimensional surface. In case of drawing a disparity based on characteristics of images, we can not abstract the depth information correctly if resemblant characteristics are repeated on the boundary region of an object. A binocular disparity is decided in a model of neural circuit by abstraction, synthesis, and correction of a disparity. And we propose a method which restores three-dimensional shape by correcting a depth information, and also restores a three-dimensional surface by mapping a left input image on the restored three-dimensional shape. And we confirmed that the computation time for disparity abstraction can be greatly reduced through the simulation.

• Journal of Korean Ophthalmic Optics Society
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• v.12 no.1
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• pp.53-59
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• 2007

A commonly used device to determine fixation disparity curves is the Wesson Fixation Disparity Card. A fixation disparity curve is 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 are used to aid in the diagnosis and management of binocular vision disorders include the x-intercept, y-intercept, curve slope and curve type. Fixation disparity curves were measured on 102 subjects with the Wesson fixation disparity card. The purpose of this study is to investigate distribution of the curve types obtained with Wesson card. Fixation Disparity by Wesson Fixation Disparity Card were that in case of type I 63.0%, in case of type II 0.0%, in case of type III 25.0% and in case of type IV 12.0%.

• Current Optics and Photonics
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• v.2 no.4
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• pp.348-355
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• 2018

How to measure the creepage distance of an insulator quickly and accurately is a problem for the power industry at present, and the noticeable concern is that the high voltage insulation equipment cannot be measured online in the charged state. In view of this situation, we develop an on-line measurement system of creepage distance for high voltage insulators based on binocular stereo vision. We have proposed a method of generating linear structured light using a conical off-axis mirror. The feasibility and effect of two ways to solve the interference problem of strong sunlight have been discussed, one way is to use bandpass filters to enhance the contrast ratio of linear structured light in the images, and the other way is to process the images with adaptive threshold segmentation and feature point extraction. After the system is calibrated, we tested the measurement error of the on-line measurement system with a composite insulator sample. Experimental results show that the maximum relative error is 1.45% and the average relative error is 0.69%, which satisfies the task requirement of not more than 5% of the maximum relative error.

• Journal of Korean Ophthalmic Optics Society
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• v.14 no.3
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• pp.51-57
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• 2009

Purpose: The purpose of this study was to determine if monocular and binocular accommodative facility tests would be useful in diagnosing general binocular dysfunctions. Methods: 95 symptomatic children, who were selected from comprehensive vision tests, were classified into four groups (29 subjects with accommodative dysfunctions, 28 subjects with vergence dysfunctions, 25 subjects with combined accommodative and vergence dysfunctions, 13 subjects with normal binocular functions). Monocular and binocular accommodative facility was measured with ${\pm}$2.00 D flipper lenses. Results: Statistical analysis revealed that binocular accommodative facility measurement was significantly lower than monocular accommodative measurement in the vergence dysfunction group (p<0.01). However, there were no differences between monocular and binocular accommodative facility measurements in the group of accommodative or combined accommodative and vergence dysfunction (p>0.05). In addition, subjects with general binocular dysfunctions performed significantly poorer than subjects with normal binocular function on monocular and binocular accommodative facility (p<0.000). Conclusions: As a result of this study, monocular and binocular accommodative facility test, which could differentiate dysfunction from normal as well as between dysfunctions, indicated useful means for diagnosis of general binocular dysfunctions.