• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.21 no.6
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• pp.19-25
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• 2007

We studied prism design method for actual light source that have bulk in order to accomplish particular intensity distribution. When we know incidence angle and try to send ray to given direction, numerical formula that yields prism vertical angle, and then vertical angles were calculated sequentially. After analyzing problem that supposing to point light source, supplemented this and derived applicable prism design method on bulk light source. The intensity distribution and efficiency that came out by each design results were compared and analyzed, we got improved results through supplemented design method.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.21 no.2
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• pp.155-164
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• 2003

The entrance of non prism totalstation brought the application possibility to many fields including a topographic survey and a facility measurement. In this research we would try to examine the errors and the problems which will be happened in measuring object with non prism totalstation and to evaluate the accuracy and applicability. For this purposes, We checked accuracy change according to the observation ang1e and material of the object, and analyzed how much accuracy was effected with the color of the object surface and laser divergency which is proportional to the distance. By measuring the facility practically and analyzing it's results, We evaluated possibility of practical use of a non prism totalstation for a facility measurement. Consequently, We propose that the observation accuracy of non prism totalstation is not depend on the hardness or material of the object and can get a good result only when we use non prism totalstation with coaxial focusing system for a facility survey.

• Journal of Digital Convergence
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• v.10 no.11
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• pp.485-491
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• 2012

To investigate the difference in the value of horizontal heterophoria measured in phoria test of about normal 72 college students, using both Von Graefe test and Maddox rod test. We used two different methods which are Von Graefe test and Maddox rod test on full correction condition at the long distance. Using Von Graefe test of horizontal heterophoria Measurement, We measured 21 patients(29%) for orthophoria, 36 patients(50%) for exophoria and 15 patients(21%) for esophoria at distance. Using Maddox rod test of horizontal heterophoria Measurement, We measured 36 patients(50%) for orthophoria, 26 patients(36%) for exophoria and 10 patients(14%) for esophoria at distance. Each test average were $0.93{\Delta}$ BI for Von Graefe test, $0.96{\Delta}$ BI for Maddox rod test. We could not find the definite difference about the value of horizontal heterophoria aby testing method. Furthermore, heterphoria AC/A ratio was found to vary from 1.0 to 8.8 and its relationship to refractive error could not be determined.

• Journal of Korean Ophthalmic Optics Society
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• v.20 no.2
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• pp.229-235
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• 2015

Purpose: This study was undertaken to study on visual function before and after prescription of vertical prism. Methods: 80 subjects (10-30ages) who had been precribed vertical prism and 1 year after they were represcribed vertical prism. Results: Phoria (p=0.000), supra vergence (p=0.000), NPC (p=0.003), NPA (right eye) (p=0.005), NPA(left eye) (p=0.000) showed a significant change. Conclusion: Vertical prism prescription was reduced during revisit. Supra vergence, NPC, NPA(right eye), NPA(left eye) showed a significant change. Binocular Accommodative lag was not associated with vertical prism prescription and binocular vision findings.

• 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.18 no.4
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• pp.509-517
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• 2013

Purpose: The purpose of this study is developing the 2.6 ${\times}$ optical scope with a Abbe-K$\ddot{o}$nig prism. Methods: First, considering the size of the effective aperture and the focal length of the objective lens, we designed an Abbe-K$\ddot{o}$nig prism. Next, we calculated the optical and geometric distances of Abbe-K$\ddot{o}$nig prism designed in this way. After allocating the focal length of the objective lens and the eyepiece lens so as to satisfy the magnification and optical effective distance of the entire system by using this calculation result, we completed the entire system by optimizing this optical system. Results: We were able to complete the optical scope of about 2.6 ${\times}$ magnification by designing an objective lens with a focal length of 63.13 mm which was composed of two pieces, an eyepiece with a focal length of 24.3 mm which was composed of four pieces, and an Abbe-K$\ddot{o}$nig prism with a face length 11.5 mm. Conclusions: We designed and fabricated an optical scope with 2.6 ${\times}$ magnification employing an Abbe-K$\ddot{o}$nig prism. Then, this system became the compacted optical system with a barrel diameter of 31 mm, characterized by an effective aperture of 12.0 mm and an effective optical barrel length of 103 mm and a resolution of 200 cycles/rad at 50% MTF criterion within the half viewing field angle of $6.42^{\circ}$.

• Journal of Korean Ophthalmic Optics Society
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• v.13 no.4
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• pp.83-88
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• 2008

Purpose: To design an anamorphic aspherical prism lens for the HMD optical system. Methods: First, we get the initial data, needed in design, which are distances between each surface etc., by analyzing user's demended specifications and by drawing geometrically the shape of prism lens by using CAD. Based on these data and using 'ode V' which is an optical design software, we could progress the optimization in which we treat the coefficients of the anamorphic aspherical surface as the principal variables. To reduce the cost in DTM manufacturing, we would optimize the optical system with the transmitting surface, existed in the direction of video device among 3 surfaces of the prism lens, remaining as a plane. Results: we could design one anamorphic aspherical prism lens which has the finite ray aberration of 15 ${\mu}m$, the distortion of 0.5%, and the MTF value of 0.3 over at 36 lp/mm for the video device of 12 mm ${\times}$ 9 mm size. Conclusions: We designed a prism lens used for HMD. This prism lens has the optical capacities of 15 ${\mu}m$ finite ray aberration and 0.5% distortion for the video device of 12 mm ${\times}$ 9 mm size, and become the optical system having the MTF value of 0.3 over at 36 lp/mm.

• Journal of Korean Ophthalmic Optics Society
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• v.12 no.3
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• pp.39-48
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• 2007

The stimulus of accommodation A, the stimulus of convergence C and the prism diopter ${\Delta}$ are reviewed and redefined more obviously. How the A and C are managed in the practice are reviewed and summarized. As a result, the common practical process of the binocular vision findings is most suitable in the case of the $l_c=26.67mm$, where the near distance is measured from the test lens to the near target and its value is 40 cm and the average of the P.D equal to 64 mm. The $l_c$ is the distance between the test lens and the center of rotation. Those values were used at calculating the various values in this paper. The error of the stimulus of accommodation values which are evaluated by the practically used formula (5) are calculated. Where the distance between lens and the principle point of eye is 15.07 mm ($=l_H$). The incremental stimulus of convergence values P' caused by the addition prism $P_m$ are evaluated by the recursion computation method. The P' are varied with the $P_m$, the distance $p_c$ between the prism and the center of rotation, the initial convergence value (or inverse target distance) $C_o$ and the refractive index n of the prism material. The recursion computation method and the other formulas are described in detail. In this paper n=1.7 is used. The two factors by which the P' is increased are exist. The one which is major is the property by which the values of convergence whose unit is ${\Delta}$ are not added in the generally way. The other is the that the actual power of the prism is varied with the angle of incidence light. And the P' is decreased remarkably by an increase in the $p_c$ and $C_o$. The $P^{\prime}/P_m$ are calculated and graphed which are varied with the $p_c$ and $C_o$, where the $P_m=20{\Delta}$, P.D=64 mm and n=1.7. The index n dependence of the $P^{\prime}/P_m$ is negligible (refer to fig. 6). The $p_c$ are evaluated at which the P' equal to the $P_m$ for various $P_m$ (refer to table 1). The actual values of the stimulus of convergence and accommodation which are manipulated simply in the practice are calculated. Two graphical forms are suggested. The one is like as the commonly used one. But the stimulus of convergence and of accommodation values in the practice are positioned at the exact positions when the graphic is made (refer to fig. 9). The other is the form that the incremental stimulus of convergence values caused by the addition prisms are represented at actual positions (refer to fig. 11).

• Journal of Korean Ophthalmic Optics Society
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• v.15 no.3
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• pp.247-255
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• 2010

Purpose: Developing a roofed Pechan prism type scope with long eye relief. Methods: To reduce the overall length and to lengthen the eye relief of scope, the objective part was designed by adopting the roofed Pechan prism and also the eyepiece part was designed by adopting the field lens with minus refractive power in front of reticle, respectively. Finally, by integrating above two parts, the roofed Pechan prism type scope with 90 mm eye relief was developed. Results: The characteristics of the developed and fabricated scope with 90 mm eye relief by integrating the objective part with the roofed Pechan prism and the eyepiece part with minus refractive power had the magnification of $+3.0{\times}$, the length from the 1st lens to the last lens of about 121 mm, the barrel diameter of 28 mm, and the effective objective-diameter of 17 mm. Also it was found that the line width of resolution was about 900 cycles/rad at the 50% MTF value criterion. Conclusions: We could design and manufacture the roofed Pechan prism type scope with 90 mm eye relief, the characteristics of which had the magnification of $3.0{\times}$, the MTF above 50% at 900 cycles/rad, and the length from the 1st lens to the last lens of about 121 mm.

• Journal of Satellite, Information and Communications
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• v.12 no.2
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• pp.11-14
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• 2017

In this paper, we introduce a method of light focusing effect using prism structure to solve optical discontinuity of conventional external signage LED panels. The prims structures were patterned on a transparent polycarbonate substrate with MEMS and femto-second laser process. We have confirmed that the patterned prism structures on the substrate made artificial LED lights on empty space between the panels by light guide effect of the structure. The artificial light's lateral positions were controlled by thickness of polycarbonate substrate. This cost effective prim patterned transparent film can be utilized on digital signage LED panels to achieve good optical communication.