• Journal of Korean Ophthalmic Optics Society
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• v.13 no.4
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• pp.109-114
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• 2008

Purpose: To assess the reproducibility and repeatability for each color vision test method. Methods: The subjects for color vision test were 30 students without congenital color vision deficiency and they major in optometry in a university, Korea. The type of color vision test selected for this study were Hans color vision test, Hans 15 hue test and Lanthony D 15 hue test. The Ishihara test was added for assessment of reliability of inter-tester. Results: All of the subjects were classified into normal at pseudoisochromatic plates, but one subject's result showed mild blue-yellow color deficiency at Hue discrimination. Results of 3 repeated test for subjects and inter-tester examination showed no errors at pseudoisochromatic plates. There were differences in mild errors among repeated test at Hue discrimination, but no differences were found in the results of repeated test to classify color vision deficiency. Conclusion: Each tester had better be more skilled to test even simple color vision test for eliminating the possibility of mild errors. Each subject might just as well be careful in color vision test. It is required to test both method of pseudoisochromatic plates and Hue discrimination in screening test.

• The Journal of Korean Medicine
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• v.35 no.2
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• pp.41-46
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• 2014

Objectives: We have treated people who have color vision defects with oriental medicine; here we demonstrate several representative cases to illustrate the effectiveness of our treatment. Material and methods: We recruited study patients who visited one oriental hospital for color vision defects. We show several representative cases to illustrate the effectiveness of our treatment. The study initially consisted of 178 subjects who took part during a 3-year period. Subjects, all of whom consented to this treatment and trial, were classified by those who have a color vision defect and those who don't by the Ishihara test and another by the Hahn color vision test. We tried color vision correction treatment with acupuncture. Acupuncture therapy where the retina and optic nerves were activated was conducted in parallel with vision correction. Assessment of therapy was conducted at 30 times, 60 times, 90 times, or 120 times of therapy. Results: Assessment of therapy was performed by conducting treatment 30 times, 60 times, 90 times, or 120 times. Surprisingly, all subjects could correctly recognize color after the treatment; although there were case by case differences according to the number of therapy treatments each individual received. Conclusions: Color vision defects can be treated. To enable those with color vision defects to enjoy better quality of life and increased opportunity in color vision-dependent job fields, therapy to correct the problem is a viable option.

• Journal of Korean Ophthalmic Optics Society
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• v.12 no.3
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• pp.89-91
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• 2007

Color vision test was conducted to elementary school students at age of 9 to 13, with total subject number of 598 which live in Gwang Ju area. 325 (54.3%) boys and 273 (45.7%) girls were subjected using Hahn Color Vision test to find out color recognition problems. 1. Ratios of color vision abnomality were 6.25% in 9 year old students, 9.2% in 10 year old students, 8.4% in 12 year old students, 7.8% in 13 year old students, which means 7.9% of the total 598 subjects had color recognition matters. 2. Red-Green dyschromatopsia was 7.8% of the total 598 subjects which includes most of subjects. None of them had green-yellow recognition problem. Full dyschromatopsia had frequency of 0.2%. 3. 10.7% of boys had color vision abnormality, while 10.7% of girls had color vision abnormality, which means that boys have color recognition problems with higher rate than girls.

• Journal of Preventive Medicine and Public Health
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• v.41 no.6
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• pp.397-406
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• 2008

This paper reviews the published literature that is concerned with color vision impairment from industrial and environmental exposure to neurotoxic substances, and we evaluated whether testing for color vision impairment could be an affordable procedure for assessing these neurotoxic effects. In general, most cases of congenital color vision impairment are red-green, and blue-yellow impairment is extremely rare. However, most of the acquired color vision impairment that is related to age, alcohol or environmental factors is blue-yellow impairment. Therefore, many studies have been performed to identify this relationship between exposure to neurotoxic substances, such as organic solvents and heavy metals, and the prevalence of blue-yellow color vision impairment. The test for color vision impairment is known to be very sensitive to the early signs of nervous system dysfunction and this can be useful for making the early diagnosis of neurotoxic effects from exposure to very low concentrations of toxic substances.

• Journal of the Optical Society of Korea
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• v.17 no.4
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• pp.344-349
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• 2013

This paper proposes a simulation algorithm to assess the gradual yellowing vision of the elderly, which refers to the predominance of yellowness in their vision due to aging of the ocular optic media. This algorithm employed the spectral transmittance property of a yellow filter to represent the color appearance perceived by elderly people with yellow vision, and modeled the changes in the color space through a spectrum change in light using the yellow filter effect. The spectral reflectivity data of 1269 Munsell matte color chips were used as reference data. Under the standard conditions of a D65 illuminant and a $10^{\circ}$ observer of 1964 CIE, the spectrum of the 1269 Munsell colors were processed through the yellow filter effect to simulate yellow vision. Various degrees of yellow vision were modeled according to the transmittance percentage of the yellow filter. The color differences before and after the yellow filter effect were calculated using the DE2000 formula, and the color pairs were selected based on the color difference function. These color pairs are distinguishable through normal vision, but the color difference diminishes as the degree of yellow vision increases. Assuming 80% of yellow vision effect, 17 color pairs out of $(1269{\times}1268)/2$ pairs were selected, and for the 90% of yellow vision effect, only 3 color pairs were selected. The result of this study can be utilized for the diagnosis system of gradual yellow vision, making various types of test charts with selected color pairs.

• Agricultural and Biosystems Engineering
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• v.4 no.1
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• pp.16-21
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• 2003

In the agricultural field, a machine vision system has been widely used to automate most inspection processes especially in quality grading. Though machine vision system was very effective in quantifying geometrical quality factors, it had a deficiency in quantifying color information. This study was conducted to evaluate color of beef using machine vision system. Though measuring color of a beef using machine vision system had an advantage of covering whole lean tissue area at a time compared to a colorimeter, it revealed the problem of sensitivity depending on the system components such as types of camera, lighting conditions, and so on. The effect of color balancing control of a camera was investigated and multi-layer BP neural network based color calibration process was developed. Color calibration network model was trained using reference color patches and showed the high correlation with L*a*b* coordinates of a colorimeter. The proposed calibration process showed the successful adaptability to various measurement environments such as different types of cameras and light sources. Compared results with the proposed calibration process and MLR based calibration were also presented. Color calibration network was also successfully applied to measure the color of the beef. However, it was suggested that reflectance properties of reference materials for calibration and test materials should be considered to achieve more accurate color measurement.

• Journal of Biosystems Engineering
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• v.32 no.4
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• pp.256-262
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• 2007

Image processing systems have been used to measure the plant parameters such as size, shape and structure of plants. There are yet some limited applications for evaluating plant colors due to illumination conditions. This study was focused to present adaptive methods to analyze plant leaf color regardless of illumination conditions. Color patches attached on the calibration bars were selected to represent leaf colors of lettuces and to test a possibility of health monitoring of lettuces. Repeatability of assigning leaf colors to color patches was investigated by two-tailed t-test for paired comparison. It resulted that there were no differences of assignment histogram between two images of one lettuce that were acquired at different light conditions. It supported that use of the calibration bars proposed for leaf color analysis provided color constancy, which was one of the most important issues in a video color analysis. A health discrimination equation was developed to classify lettuces into one of two classes, SOUND group and POOR group, using the machine vision. The classification accuracy of the developed health discrimination equation was 80.8%, compared to farmers' decision. This study could provide a feasible method to develop a standard color chart for evaluating leaf colors of plants and plant health monitoring system using the machine vision.

• Journal of Korean Ophthalmic Optics Society
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• v.16 no.3
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• pp.307-312
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• 2011

Purpose: To investigate the prevalence of congenital and age-related color vision deficiencies over a wide range of ages among residents in two urban communities of Kyeonggi-Do. Methods: A total of 935 subjects, consisting of 452 males and 483 females, participated in this study. Lanthony D-15 desaturated panels test were used to assess color vision. Results: Prevalence of color vision deficiency was 4.81% for total, 6.64% for males and 3.11% for females. Congenital color vision deficiency was 3.54% for males and 0.41% for females. Tritan deficiency, which was the post-natal age-related, was 2.99% (3.32% for males, and 2.69% for females). Conclusions: The result imply that color vision deficiencies is influenced by age. As an age-related color vision deficiencies, Tritan is most frequently found in the age group over 50.

• Journal of Korean Ophthalmic Optics Society
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• v.5 no.2
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• pp.5-9
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• 2000

The visual evoked potential was electrophysiological method for the identify of the EEG response on visual cortex. This test was objective test method on the eye function. This study was used the visual evoked potential for the objective color test. The subjects was a normal color function in Korean adults. The test condition was performed on the differens distance and illumination. According to convergence condition of color vision target. On the appearance of EEG wave of visual stimulation on visual cortex. The most EEG wave style was delta wave, and the next amount wave form was beta wave and theta wave, and the least EEG wave form was alpha wave. The histogram of amplitude of EEG wave form was almost non-Gaussian shape, and the phase diagram of amplitude was almost all linear shape. On the kinds of color vision target, the frequency of EEG wave style appeared a similar results.

• Journal of Korean Ophthalmic Optics Society
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• v.10 no.4
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• pp.329-337
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• 2005

This study investigated prevalence of color vision loss different from children's residence. The study subjects are 3 to 6 grade's children of elementary school in four areas. The blood lead and urinary mercury were analysed using Atomic Absorption Spectroscopy. All of participations' blood lead and urine mercury concentration were below suggested level of concern such as criteria by CDC and ATSDR. Color vision was assessed by the Lanthony D-15 desaturated panel. Color vision loss was quantitatively established by the Color Confusion Index (CCI) and qualitatively classified by type of acquired dyschromatopsia according to Verriest's classification. The prevalence of color vision loss and CCI value for children in industrial area was significantly higher than other areas(p<0.05). However blood lead and urinary mercury concentration level was not correlated to the color vision loss. Therefore we believed that other environmental neurotoxic substance except metal had an effects on color vision loss for children in industrial area.