• Current Optics and Photonics
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• v.5 no.2
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• pp.134-140
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• 2021

In this paper, I introduce a novel design method of a high performance nanophotonic beam deflector providing broadband operation, large active tunability, and signal efficiency, simultaneously. By combining thermo-optically tunable vanadium dioxide nano-ridges and a metallic mirror, reconfigurable local optical phase of reflected diffraction beams can be engineered in a desired manner over broad bandwidth. The active metagrating deflectors are systematically designed for tunable deflection of reflection beams according to the thermal phase-change of vanadium dioxide nano-ridges. Moreover, by multiplexing the phase-change supercells, a robust design of actively tunable beam splitter is also verified numerically. It is expected that the proposed intuitive and simple design method would contribute to development of next-generation optical interconnects and spatial light modulators with high performances. The author also envisions that this study would be fruitful for modern holographic displays and three-dimensional depth sensing technologies.

• Journal of the Korea Computer Graphics Society
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• v.3 no.1
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• pp.9-15
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• 1997

Most rendering research has concentrated on two sub-problems: modeling the reflection of light sources, and calculating the direct and indirect illumination from light sources and other surfaces. As Kolb wrote in [1], the camera and lens model is an important key component of a rendering system. In this paper we describe a bump-mapping method using camera lens. It allows another level of control in rendering. We developed an efficient framework to develop customized bump mapping lens and combine with other sequence of lens elements to create various effects as shown in Figure 2,3,4,5.

• Proceedings of the IEEK Conference
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• 2007.07a
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• pp.337-338
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• 2007

The present paper proposes the method which improves a record and remaking efficiency of the optical pickup as applying the mirror where Phase Shift(PS) principle is applied to optical pickup. Plan to get a circularly polarized light quality above quality which is embodied through Existing Quater Wave Plate(QWP) and a function of total reflection mirror as applying PS mirror which integrates QWP with the function of the total reflection to optical pickup. In the present paper, embody circularly polarized light quality through applying PS mirror to optical pickup, and it through, plan to propose to come true the optimization of recording and remaking CD/DVD disc.

• Korean Journal of Optics and Photonics
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• v.13 no.5
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• pp.408-413
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• 2002

We demonstrated a polarization dependent type 2$\times$2 optical switch, using a binary reflection type SLM. Reflection type FLC was used as a half wave retardation plate. Two inputs were controlled by each SLM for the desired output direction. In conclusion, in the "1" state the average optical loss was 6.6 ㏈, and in the "0" state the average optical loss was 14.6 ㏈, and measured the switching speed as 75 $mutextrm{s}$. By using this method, a polarization dependent type 2$\times$2 optical switch can be demonstrated and the possibility of a 4-port WDM optical switch also verified.

• Proceedings of the Korean Vacuum Society Conference
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• 2012.08a
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• pp.85-85
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• 2012

For effective light harvesting, a design weighting should be implemented in a front geometry, in which the incident light transmits from a surface into a light-active layer. We designed a three-dimensionally patterned transparent conductor layer for effective light management. A transparent conductive oxide (TCO) film was formed as three-dimensional structures. This efficiently drives the incident light at the front surface into a Si absorber to yield a reduction in reflection and an enhancement of current. This indicates that an optimum architecture for a front TCO surface will provide an effective way for light management in solar cells.

• IEMEK Journal of Embedded Systems and Applications
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• v.10 no.2
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• pp.101-108
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• 2015

In this paper, a robust traffic light detection method is proposed by using vision sensor and DGPS(Difference Global Positioning System). The conventional vision-based detection methods are very sensitive to illumination change, for instance, low visibility at night time or highly reflection by bright light. To solve these limitations in visual sensor, DGPS is incorporated to determine the location and shape of traffic lights which are available from traffic light database. Furthermore the geometric relationship between traffic light and vision sensor is used to locate the traffic light in the image by using DGPS information. The empirical results show that the proposed method improves by 51% in detection rate for night time with marginal improvement in daytime environment.

• Proceedings of the Optical Society of Korea Conference
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• 2004.07a
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• pp.190-191
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• 2004

• 한국정보디스플레이학회:학술대회논문집
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• 2009.10a
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• pp.1519-1522
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• 2009

We describe a 32" liquid-crystal display (LCD) with multi-touch sensing capability by integrating IR detector arrays onto the LED backlight plate. A transparent light guide is placed in front of the display screen, with IR LEDs disposed at its edges and emitting IR light into the light guide, the light is trapped by total internal reflection within the light guide to be as touch-sensing light. A physical contact with the acrylic plate surface will stimulate some trapped light to be escaped from the light guide and pass through LCD panel to be detected by the IR detectors. The touch-sensing LCD with this configuration can locate simultaneous multiple touche points on the touchable surface.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.22 no.10
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• pp.850-853
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• 2009

We have optimized the device structure by using the dielectric layer such as anti-reflection thin film to improve the emitting efficiency of white organic light emitting device (WOLED). Basically, dielectric layer with anti-reflection characteristics can enhance the emitting efficiency of WOLED by compensating the refractive index of organic layer, ITO, and Glass. Here, WOLED was designed and optimized by Macleod simulator. The refractive index of 1.74 was calculated for Dielectric layer and was selected as $TiO_2$. The optimal thicknesses of $TiO_2$ and ITO were 119.3 and 166.6 nm, respectively, at the wavelength of 600 nm. The transmittance of ITO was measured with the thickness variation of dielectric layer and ITO in Organic layer/ITO/Dielectric layer structure. The transmittance of ITO was 95.17% and thicknesses of $TiO_2$ and ITO were 119.3 and 166.6 nm, respectively. This result, calculated and measured values were coincided.

• Korean Journal of Optics and Photonics
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• v.20 no.1
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• pp.57-60
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• 2009

We consider introducing an optical thin film to the light guiding wall of a pixel in order to enhance the light guiding efficiency of a CMOS image sensor. Simulating the reflectance as a function of the incidence angle using the Essential Macleod program, we find that the range of total internal reflection is greatly increased for several materials. Particularly when air is chosen as the thin film material, the critical angle of total internal reflection could be shifted to about 50 degrees.