• The Journal of the Convergence on Culture Technology
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• v.6 no.2
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• pp.183-190
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• 2020

This study was designed to investigate the current state of lens wearing and care, and to investigate eye discomfort according to the care method. Data of 209 female college students wearing lenses for more than 1 year were analyzed using the SPSS / WIN 22.0 program. 40.2% of female students wear lenses every day and 97.1% wear all day. However, only 45.4% of students washed it daily, and only 17.7 % used protein remover during wash, which resulted in poor management. 98.1% of students complained of discomfort due to the lens, and the Ocular Surface Index (OSDI) scored 42.88 ± 15.25, which was classified as a severe dry eye and threatened eye health. Therefore, it is necessary to improve students' awareness of lens management, and periodical lens inspection and management education are needed.

• Proceedings of the Optical Society of Korea Conference
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• 2009.10a
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• pp.153-154
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• 2009

In this study, a new accommodation-dependent crystalline lens with a constant volume and homogeneous refractive index is developed. The human lens parameters, such as curvature and thickness, are calculated at the central parts of the lens, and the asphericity is adjusted at the peripheral parts of the lens due to accommodation. We propose a accommodating schematic eye which is suitable for easy paraxial calculations because the refractive index of the lens remains uniform and constant.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.42 no.5 s.305
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• pp.79-84
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• 2005

In this paper, we developed an omni-directional surveillance and motion detection method. The fish-eye lens provides a wide field of view image. Using this image, the equi-distance model for the fish-eye lens is applied to get the perspective and panorama images. Generally, we must consider the trade-off between resolution and field of view of an image from a camera. To enhance the resolution of the result images, some kind of interpolation methods are applied. Also the moving edge method is used to detect moving objects for the object tracking.

• 한국HCI학회:학술대회논문집
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• 2009.02a
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• pp.601-605
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• 2009

Due to the fact that fish-eye lens can provide super wide angles with the minimum number of cameras, field-of-view over 180 degrees, many vehicles are attempting to mount the camera system. Camera calibration should be preceded, and geometrical correction on the radial distortion is needed to provide the images for the driver's assistance. However, vehicle fish-eye cameras have diagonal output images rather than circular images and have asymmetric distortion beyond the horizontal angle. In this paper, we introduce a camera model and metric calibration method for vehicle cameras which uses feature points of the image. And undistort the input image through a perspective projection, where straight lines should appear straight. The method fitted vehicle fish-eye lens with different field of views.

• Proceedings of the Optical Society of Korea Conference
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• 2006.07a
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• pp.77-78
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• 2006

We introduced a new method for lens design that eyepiece is combined with the Navarro eye. Following Optimization of lens system-Navarro eye combination, final design has the modulation transfer function(MTF) of 0.9 at 50 cycle/mm.

• Proceedings of the KSME Conference
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• 2000.11a
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• pp.596-601
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• 2000

In a robot/vision system, the vision sensor, typically a CCD array sensor, is mounted on the robot hand. The problem of determining the relationship between the camera frame and the robot hand frame is refered to as the hand-eye calibration. In the literature, various methods have been suggested to calibrate camera and for sensor registration. Recently, one-step approach which combines camera calibration and sensor registration is suggested by Horaud & Dornaika. In this approach, camera extrinsic parameters are not need to be determined at all configurations of robot. In this paper, by modifying the camera model and including the lens distortion effect in the perspective transformation matrix, a new one-step approach is proposed in the hand-eye calibration.

• Journal of Korean Ophthalmic Optics Society
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• v.5 no.1
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• pp.155-157
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• 2000

A variable process of blur circle is calculated for a artificial hyperopia. The calculation is used to the value of Gullstrand's theoretical eye and a method of geometrical optics. The theoretical eye simplified a entrance pupil and the retina. Ophthalmic lens and eye changed a equivalent lens. Refractive power of a equivalent lens is converted to focal length within theoretical eye, and this is calculated about relation of a blur circle on the retina and ophthalmic lens.

• Korean Journal of Optics and Photonics
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• v.18 no.2
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• pp.167-170
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• 2007

In this study, clinical data for emmetopia in young Koreans was taken in order to design the finite schematic eye, which had optical properties of real eyes including spherical aberration, astigmatism, field curvature and distortion. Furthermore, the crystalline lens with GRIN medium was optically analyzed, and the finite schematic eye with the GRIN crystalline lens was designed.

• Journal of Korean Ophthalmic Optics Society
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• v.5 no.2
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• pp.107-113
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• 2000

This study has analyzed soft contact lens care-after-sale and periodic examinations at optical shops and eye clinics. And I wish to make that use of educational data for the soft contact lens lesson of the department of ocular optics. This questionnaire studied the status of care for soft contact lens and periodic examination, of students who wears soft contact lens. The results are as follows: First, 7.5% of students questioned wore soft contact lens. More women than men wore soft contact lens. The soft contact lens wearers purchased lens mainly at optical shops. 78.5% of them wore daily wear lens. Because of cosmetic advantages of soft contact lens. 47.9% of them wore soft contact lens. 72.5% of them wore soft contact lens less than 12 hours per a day. 32.0% of them has worn soft contact lens more than 6 months less than 1 year. 51.1% of them experienced irritation. 39.7% of them have exchanged soft contact lens between 6 and 9 months. Secondly, when purchasing lenses. 60% of soft contact lens wearers were given instructions of general care, such as duration of wearing lens, how to remove protein, how to store, and how to sterilize at both of eye clinics and optical shops. But the proportion of instructions, such as side effects and periodic examination which were given to soft contact lens wearers, is lower both at eye clinics and optical shops. Especially at optical shops, the proportion of instruction for periodic examination, is lower than at eye clinics(p<0.05). Thirdly, The proportion of operations of periodic examinations after use of soft contact lens both at eye clinics and optical shops, is low. The soft contact lens wearers have had more periodic examinations at eye clinics than at optical shops. But the rate of non-periodic examination at optical shop is 87.9%. And for periodic examinations, general care was done at optical shops. On the other hand, eye examinations, general care, and treatments were done more at eye clinics. Fourthly, 60.3% of the soft contact lens wearers understood the necessity of the periodic examinations, but actually, only 6.4% of them were given the schedule for the periodic examinations, and 2.5% of them were given at an optical shop(p<0.01).

• Journal of the Korea Society of Computer and Information
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• v.13 no.4
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• pp.97-103
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• 2008

This study is to present a fainting motion recognizing method by using fish-eye lens images to sense emergency situations. The camera with fish-eye lens located at the center of the ceiling of the living room sends images, and then the foreground pixels are extracted by means of the adaptive background modeling method based on the Gaussian complex model, which is followed by tracing of outer points in the foreground pixel area and the elliptical mapping. During the elliptical tracing, the fish-eye lens images are converted to fluoroscope images. the size and location changes, and moving speed information are extracted to judge whether the movement, pause, and motion are similar to fainting motion. The results show that compared to using fish-eye lens image, extraction of the size and location changes. and moving speed by means of the conversed fluoroscope images has good recognition rates.