• Title/Summary/Keyword: Lens of the Eye

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A Distortion Correction Method for the Fish-Eye Lens using Photogrammetric Techniques (사진측량 기법을 사용한 어안렌즈 왜곡보정에 관한 연구)

  • Kang, Jin-A;Park, Jae-Min;Kim, Byung-Guk
    • Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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    • 2007.04a
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    • pp.161-164
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    • 2007
  • The paper studies in the wide-angle lens and distortion tendency and employs the correction techniques suitable to the fish-eye lens using the existing photographic survey methods. After carrying out the calibration of the the fish-eye lens, we calculated the correction parameters, and then developed the method that convert the original image-point to new image-point correcting distortion. The objectives of suggested calibration method in this paper are to calibrate the image of the the fish-eye lens used in the computer-vision and the control-instrumentation field widely. The proposed technique expects to improve the accuracy of the image of the fish-eye lens in the indoor tracking and monitoring field. Also the referenced cross point auto-extraction program is embodied for improving efficiency of the lens correction techniques. Consequently, this calibration method would be applied to the automated distorting correction method on not only the fish-eye lens also general lens.

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Development on a Relay Lens Type Scope with 70 mm Eye Relief (70 mm Eye Relief를 갖는 릴레이 렌즈 방식 스코프 개발)

  • Park, Seung-Hwan;Lee, Dong-Hee
    • Journal of Korean Ophthalmic Optics Society
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    • v.14 no.3
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    • pp.29-35
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    • 2009
  • Purpose: To develop a relay lens type scope with 70 mm eye relief. Methods: By using Sigma 2000 design program, we designed and manufactured a relay lens type scope with 70 mm eye relief, which is integrated after designing an objective part with relay lenses and an eyepiece part, respectively. Results: The characteristics of the relay lens type scope with 70 mm eye relief whch is designed and manufactured by methods, which integrate after respectively designing an object part with relay lenses and an eyepiece part, have the magnification of $+4{\times}$,the length from 1st lens to last lens of about 105 mm, the barrel diameter of 18mm, and the effective diameter of 13 mm. Also we know that the resolution line width is 275 cycles/rad at the 30% MTF value criterion. Conclusions: We could design and manufacture the relay type scope with 70 mm eye relief, the characteristics of which have the magnification of $+4.0{\times}$the MTF above 30% at 275 cycles/rad, and the length from 1st lens to last lens of about 105 mm.

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Review on Regulatory and Technical Standards of Radiation Protection for Lens of the Eye (수정체 방사선 방호에 관한 규제기준 및 기술기준 검토)

  • Si Young Kim;Seok-Ju Hwang;Jae Seong Kim;Jung-Kwon Son
    • Journal of Radiation Industry
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    • v.18 no.1
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    • pp.1-7
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    • 2024
  • The International Commission on Radiological Protection (ICRP) lowered the annual equivalent dose limit of lens of the eye for radiation workers from 150 to 20 mSv in April 2011. This trend of lowering the equivalent dose limit for radiation workers has been observed worldwide, including international organizations such as the International Atomic Energy Agency (IAEA), International Organization for Standardization (ISO) and the European Commission (EC). In 2016, the Nuclear Safety and Security Commission of South Korea published research results that included a proposal for lowering the equivalent dose limit of lens of the eye for radiation workers in line with the ICRP recommendation. However, as of now, South Korea's Nuclear Safety Act and related regulations still specify an annual equivalent dose limit of lens of the eye as 150 mSv for radiation workers. The IAEA and ISO have issued guidelines regarding radiation protection for lens of the eye and recommended a dose level for the lens of the eye at 5 or 6 mSv per year for periodic monitoring of the equivalent dose for the lens of the eye.

A preliminary evaluation of the implementation of a radiation protection program for the lens of the eye in Korean nuclear power plants

  • Kong, Tae Young;Kim, Si Young;Cho, Moonhyung;Jung, Yoonhee;Son, Jung Kwon;Jang, Han;Kim, Hee Geun
    • Nuclear Engineering and Technology
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    • v.53 no.9
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    • pp.3035-3043
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    • 2021
  • Epidemiological research has revealed that radiation exposure can cause cataracts. The Korean nuclear regulatory body has proposed the reduction of the occupational dose limit for the lens of the eye from 150 mSv/y to 100 mSv/5y, with an additional limitation of not exceeding 50 mSv/y for a specific year, taking into account the recommendations of the International Commission on Radiological Protection, and the International Atomic Energy Agency. This means that radiation workers should receive the same level of radiation safety for the lens of the eye as for whole-body protection. Korean nuclear power plants (NPPs) are conducting research to establish the radiation protection program for the lens of the eye. In terms of the preliminary results of the implementation of the radiation protection program for the lens of the eye dedicated to Korean NPPs, this review article summarizes the current state of understanding of the regulations, technical guidance, eye lens dosimeters, and radiation field conditions resulting in lens dose.

Occurrence of eye abnormality in cultured red seabream (Pagrus major) and induced hybrid, red seabream Pagrus major(♀) ${\times}$ black seabream Acanthopagrus schlegeli(♂)

  • Iraida, Germogenovna Syasina;Park, In _Seok
    • Journal of fish pathology
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    • v.16 no.2
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    • pp.75-80
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    • 2003
  • Red scabream, Pagrus major , is a valuable aquaculture species in Korea , but spontaneous eye abnormality occurred in cultured individuals . The incidence of eye abnormality was 4% in the group of cultured red scebream. The abnormality was characterized by unilateral and bilateral exophthalmos, opacity and lens pathology. Lense prolapse was found in two cases. Lenses in diseased fishes was considerably small in diameter and eyes were deformed as a whole. In the group of induced hybrid red scabream Pagrus major (♀) x black seabrearn Acanthopagrus schlegeli (♂), the incidence of eye abnormality wa~ the same 4%, but only opacity was registered. Opacity was also found in two of sixteen examined Wild-caught red seabrcam. Histopathological changes of lenses in cultured red seabreem included vecuolated cytoplasm of lens fibers, necrosis of fibers in central part of lens, folding and increase in thickness of lens capsule, and epithelial proliferation beneath the anterior lens capsule. In affected eyes no parasites or gas bubbles were found.

Changes of Stereoacuity with Correction in Induced Anisometropia (유발된 부동시의 교정에 따른 입체시 변화)

  • Choi, Jin Young;Kim, Jai-Min;Kim, Hyun Jung
    • Journal of Korean Ophthalmic Optics Society
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    • v.13 no.4
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    • pp.121-126
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    • 2008
  • Purpose: To study the minimum diopter of spherical lens with normal binocular function in induced anisometropia by over-correction or under-correction in single eye. Methods: Stereoacuity of subjects without ophthalmic disease history in their twenties was measured by using Titmus-fly stereotest at 40 cm after overcorrection or under-correction in non-dominant eye or dominant eye, respectively. Results: In induced anisometropia, the stereoacuity decreased with increase of the power of added spherical lens in either nondominant eye or dominant eye. And the first reduction of stereoacuity was more prominent with the addition of (+) spherical lens than (-) spherical lens. In addition, there was more strikingly decrement of stereoacuity with addition of spherical lens to dominant eye than non-dominant eye. Conclusions: In induced anisometropia, the most outstanding reduction of stereoacuity was obtained with increment of the power of added (+) spherical lens in case of non-dominant eye with full correction and dominant eye with addition of spherical lens.

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Dry Eye Syndrome and Ocular Fatigue according to the Status of Contact Lens Wearing and Management among Female University Students (여대생의 콘택트렌즈 착용 및 관리 실태에 따른 안구건조증과 눈 피로)

  • Her, Sun;Kim, Kye Ha
    • Research in Community and Public Health Nursing
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    • v.25 no.4
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    • pp.259-269
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    • 2014
  • Purpose: The purpose of this study was to examine dry eye syndrome and ocular fatigue according to the status of contact lens wearing and management among female university students. Methods: The subjects were 195 female university students wearing contact lenses. Ocular Surface Disease Index (OSDI) and Virtual Reality Symptom Questionnaire (VRSQ) were used to determine the level of dry eye syndrome and ocular fatigue. The SPSS/WIN 21.0 program was used for analysis of data. Results: Significant differences in the level of dry eye syndrome were observed according to the period of case solution change (F=3.36, p=.037) and the reasons for the change of lens (F=4.56, p=.004). In ocular fatigue, significant differences were observed according to the price of lens (F=3.53, p=.031), rinse in storing lens in a case (t=-2.57, p=.011), and learning about contact lens (t=-2.01, p=.046). A significant positive correlation was observed between dry eye syndrome and ocular fatigue in the subjects. Conclusion: The results of this study show that some subjects have problems in wearing and management of contact lenses. Therefore, an education program related to contact lenses should be provided to contact lens wearers to improve the status of wearing and management of contact lenses.

A comparative study of contact lens wearer with dry-eye patient on tear function tests (콘텐트렌즈 착용자와 건성안 환자의 눈물 검사에 대한 비교 연구)

  • Kim, Soon-Ae;Seo, Eun-Sun;Lee, Young-Hwan;Kim, Ja-Min
    • Journal of Korean Ophthalmic Optics Society
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    • v.9 no.2
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    • pp.301-312
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    • 2004
  • This study was performed to compare the relationship between contact lens wearer and dry-eye patient. In this study, TBUT, SIT, TTT, Rose bengal staining and McMonnies dry eye symptom questionnaire were performed as a baseline. With the base data, the subjects were classified to 3 groups : 3S patients who have dry eye signs and symptoms, 38 patients who are wearing soft contact tenses, 35 subjects who have health eyes and never worn on a contact lenses as control subjects. Contact lens wearers were divided into 3 groups according to the duration of contact lens wear. There were no significant differences in TBUT, STT, TTT, Rose-bengal staining and McMonnies dry eye symptom questionnaire result between contact lens wearer group and dry eye patients group. We suggest that there are similarities in tear function tests between the dry-eye patient and the contact lens wearer.

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Use of the Texas Eye Research and Technology Center Dry Eye Questionaire (TERTC-DEQ) as a Screening Survey for Contact Lens Wearers and Nonwearers (콘택트렌즈 착용자와 비착용자의 건성안 설문조사 TERTC-DEQ의 활용)

  • Kim, Jai-Min;Kim, Yong-Hwan;Jung, Ju-Hyun
    • Journal of Korean Ophthalmic Optics Society
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    • v.12 no.4
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    • pp.127-131
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    • 2007
  • This study was designed to demonstrate the ability of Texas Eye Research and Technology Center Dry Eye Questionaire (TERTC-DEQ) to examine the distribution of self-reported dry eye symptoms and their diurnal intensity in university students and compare it with McMonnies & Ho DEQ. Two dry eye questionnaires were administered to 46 contact lens wearers and 47 nonwearers. Contact lens wearers scored higher on the TERTC-DEQ (52.2%) than McMonnies & Ho DEQ (6.5%). Non-contact lens wearers also scored higher on the TERTC-DEQ (19.1%) than McMonnies & Ho DEQ (2.1%). Ocular symptoms worsened with progression of time of day in both groups of subjects. This study suggests that TERTC-DEQ provides a first-choice diagnosis tool to obtain a comprehensive assessment of patient's symptoms, especially in comparison with McMonnies & Ho DEQ. The TERTC-DEQ is an efficient screening survey and may be use in dry eye diagnosis of contact lens-related dry eye.

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The Effects of Visual acuity increase in mono vision by the P-VEP study using Netspeg lens (Netspag Lens를 이용한 Mono vision에서 시력개선 효과에 대한 P-VEP 연구)

  • Kim, Douk-Hoon;Bae, Han-Young;Kim, Sun-Tae
    • Journal of Korean Ophthalmic Optics Society
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    • v.10 no.3
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    • pp.241-246
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    • 2005
  • The aim of the study was performed the wave analysis of P-VEP on the development of visual function using Netspeg lens in monocular of refraction error subjects. The P-VEP of three channels were recorded by the Bausch Lomb system. Ten adults (five males, five females, mean=22 years, range=19 to 23) subjects were recorded. The subjects were researched the history including the systemic health, medication, genetics, allergy, ocular disease, and so on. Visual acuity and refraction test were performed for each subject with mono vision by using the Netspeg lens. Also subjects viewed the P-VEP stimulus with mono vision through the corrected visual acuity with Netspeg lens during VEP test. The results of study suggest that the mono vision using Netspeg lens is better than with non-Netspeg lens on the visual acuity and image symptom. On the other hand, the analysis of P-VEP suggest that the amplitude of wave is larger when the eye using Netspeg lens receives the P-VEP stimulus compared with the non Netspeg lens. Also, on the wave style of P-VEP, the eye of Netspeg lens was more stable compared with the naked eye. However, on latency period of P-VEP, the eye of non Netspeg lens was more longer than the eye of Netspeg lens. But, on the other hand, the right and left eye have similar results. In conclusion, this study indicated that the visual acuity and visual function of eye of Netspeg lens used have a better than the eye of non-Netspeg lens in Mono Vision.

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