• Journal of the Korea Institute of Information and Communication Engineering
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• v.18 no.5
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• pp.1096-1102
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• 2014

In remote gaze tracking system using infra-red LEDs, calibrating the position of reflected light is essential for computing pupil position in captured images. However, there are limitations in reducing errors because variable locations of head and unknown radius of cornea are involved in the calibration process as constants. This study purposes a gaze tracking method based on pupil-corneal reflection that does not require user-calibration. Our goal is to eliminate the correction process of glint positions, which require a prior calibration, so that the gaze calculation is simplified.

• Proceedings of the IEEK Conference
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• 2009.05a
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• pp.273-275
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• 2009

The currently used methods to get this information include corneal reflection, electro-oculograph, and so on. In this paper, we propose an algorithm that is developed for the reflection of pupil by infrared. I assume that the pupil is a perfect circle in the captured eye images. The method to recognize an existing image has many data throughput very much. And the time to deal with an image data is very long. So, we did not use the camera. However we studied the algorithm to pursue the pupil to a mapping technique.

• Journal of Korean Elementary Science Education
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• v.35 no.3
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• pp.288-304
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• 2016

The purpose of this study is a review of previous studies and principles of eye-tracking techniques that are actively applied in recent elementary science education. Also it proposes to utilize the direction of eye tracking techniques in elementary science education research. Recent eye-tracking technology was developed, using the infrared pupil and the corneal reflection can be safely and accurately track the eye movements of the participants. Eye tracking has the advantage of higher temporal resolution, accessibility, convenience, objectivity, stability and safety. Analysis of the previous studies, there was a difference in the study design and analysis. The workshops and seminars are needed for accurate understanding of eye-tracking method in elementary science education research. In conclusion, the eye-tracking can be utilized such as effectiveness analysis of teaching materials and media, behaviors analysis of teachers and students in a real class, cognitive strategies and attention analysis of the student, discriminating tool of various education evaluation, etc.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.43 no.2 s.308
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• pp.19-29
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• 2006

As the security of personal information is becoming more important in mobile phones, we are starting to apply iris recognition technology to these devices. In conventional iris recognition, magnified iris images are required. For that, it has been necessary to use large magnified zoom & focus lens camera to capture images, but due to the requirement about low size and cost of mobile phones, the zoom & focus lens are difficult to be used. However, with rapid developments and multimedia convergence trends in mobile phones, more and more companies have built mega-pixel cameras into their mobile phones. These devices make it possible to capture a magnified iris image without zoom & focus lens. Although facial images are captured far away from the user using a mega-pixel camera, the captured iris region possesses sufficient pixel information for iris recognition. However, in this case, the eye region should be detected for accurate iris recognition in facial images. So, we propose a new fast iris detection method, which is appropriate for mobile phones based on corneal specular reflection. To detect specular reflection robustly, we propose the theoretical background of estimating the size and brightness of specular reflection based on eye, camera and illuminator models. In addition, we use the successive On/Off scheme of the illuminator to detect the optical/motion blurring and sunlight effect on input image. Experimental results show that total processing time(detecting iris region) is on average 65ms on a Samsung SCH-S2300 (with 150MHz ARM 9 CPU) mobile phone. The rate of correct iris detection is 99% (about indoor images) and 98.5% (about outdoor images).

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.40 no.3
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• pp.189-198
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• 2003

Videooculography (VOG) is one of the eye-movement measurement methods used for objective evaluation of vestibule -ocular reflex. A key feature of VOG is to estimate accurately the center of pupil and ocular torsion with being less influenced by the upper eyelid droop, eyelashes, corneal reflection, and eye blinks. Especially, it Is important to find the accurate center of the pupil in 3-D VOG because the inaccurate pupil center causes significant errors on measuring torsional eye movement. A new algorithm was proposed to find the center of pupil which is a little influenced by factors mentioned above. In this study, real time three-dimensional VOG which can measure horizontal, vortical, torsional eye movements, and the diameter of pupil was implemented using the proposed method.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.18 no.10
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• pp.2417-2426
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• 2014

Remote gaze tracking system calculates the gaze from captured images that reflect infra-red LEDs in cornea. Glint is the point that reflect infra-red LEDs to cornea. Recently, remote gaze tracking system uses a number of IR-LEDs to make the system less prone to head movement and eliminate calibration procedure. However, in some cases, some of glints are unable to spot. In this case, it is impossible to calculate gaze. This study examines patterns of glints that are difficult to detect in remote gaze tracking system. Afterward, we propose an algorithm to reconstruct positions of missing glints that are difficult to detect using other detected glints. Based on this algorithm, we increased the number of valid image frames in gaze tracking experiments, and reduce errors of gaze tracking results by correcting glint's distortion in the reconstruction phase.

• Journal of Korean Ophthalmic Optics Society
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• v.19 no.4
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• pp.527-532
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• 2014

Purpose: The matching of the optical center and the pupil center was measured by photographs in wearing glasses. In this study, the influences of the induced prism by the mismatching are studied. Methods: 74 subjects (148 eyes) who were spectacles wearer were participated in this study. The mean age was $29.19{\pm}12.22$ years (range 19-55 years). The facial photographs of subjects were taken while wearing spectacles. The matching of the corneal reflected image and optical center of the spectacle lens in the horizontal deviations, and the vertical deviations were measured by the observation of the photo image. The prisms induced in accordance with various frame type were calculated from the mismatching deviations. Results: The binocular horizontal deviations were $1.55{\pm}1.70mm$ for the metal frame, $1.71{\pm}2.21mm$ for the clings type plastic frame, and $1.15{\pm}1.38mm$ for the plastic frame. In the horizontal direction induced prism, the ratio over the tolerance was 23%. The ratio were the 17.6% at the BI prism, and 5.4% at the BO prism. The binocular vertical deviation comparisons were $3.93{\pm}1.91mm$ for the metal frame, $5.79{\pm}1.93mm$ for the clings type plastic frame, and 1$6.01{\pm}2.94mm$ for the plastic frame. In the vertical direction induced prism, the ratio over the tolerance was 44.6%. Based on the refraction power, the ratio were 12.2% at -0.25${\leq}-3.00$, and 32.4% at -3.00${\leq}-12.00D$. Conclusions: The induced prisms in the horizontal direction were much in the BI prism. The binocular vertical deviations of the glasses.

• Journal of Korean Ophthalmic Optics Society
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• v.5 no.2
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• pp.43-47
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• 2000

The purpose of this study is evaluate for effect quality eye care to the aged population of rural community. This study investigated one of important factors in dispensing distance pupillary distance. measured reading pupillary distance, calculated reading pupillary distance into age group and sex. I measured pupillary distance and near inter pupillary distance with corneal reflection pupillometer(shin Nippon PD-82) The objects are male and female living rural community at least 60 years old. The mean pupillary distance for distance of male and female were 63.52 mm, 61.24 mm, respectively. The mean measured reading pupillary distance of male and female were 60.12 mm, 58.08 mm, respectively. Gradient and difference between male and female were same with mean pupillary distance for distance. The result of comparison the mean difference of the mean measured reading pupillary distance and the calculated reading pupillary distance into the age group and sex. This result of changes of addition, as the age is older, the mean addition is greater than youth. I'd like to compare changes of these factors influenced by environmental factors, however I couldn't see about these. So I couldn't considered their relationship and some possible problems of wearing commercial reading glass.