• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2006년도 6th International Meeting on Information Display
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• pp.459-462
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• 2006

In this paper, we proposed a novel TFT-LCD pixel structure to compensate ${\Delta}V_p$, which is a maximum value of 1.82V in conventional pixel structure without compensation. We achieved a maximum value of 60mV in proposed pixel structure by integrating a dummy switch TFT in each pixel. The proposed TFT-LCD pixel structure with a remarkably reduced ${\Delta}V_p$ allows ultra high picture quality AMLCDs.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2005년도 International Meeting on Information Displayvol.II
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• pp.898-901
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• 2005

We propose a novel pixel structure using bootstrapped voltage programming for amorphoussilicon TFT backplane of AM-OLED (Active Matrix-Organic Light Emitting Diode) displays. The proposed structure is composed of two TFTs and one capacitor. It operates at low drive voltage ($0{\sim}5V$) which can reduce power consumption comparing with the conventional pixel circuit structure using same OLED material. Also, it can easily control dark level and use commercial mobile LCD ICs. In this paper, we describe the operating principle and the characteristics of the proposed pixel structure and verify the performance by SPICE simulation comparing with the conventional pixel structure.

• 한국게임학회 논문지
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• 제3권1호
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• pp.86-93
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• 2003

픽셀의 형태학적인 특성을 고려한 필터링 기법을 사용한 새로운 앤티에얼리아싱 방법을 제안한다. 에얼리아싱은 직선, 모서리나 다각형 물체에서 발생 할 수 있다. 이 문제는 모니터의 제한된 해상도에 따른 것으로 영상을 이용한 리얼리티 구현을 목적으로 하는 부문에 있어서는 많은 영향을 미칠 수 있다. 이 같은 문제점을 해결하기 위하여 물체의 윤곽선 중 의미가 있는 윤곽선을 찾고 이 데이터를 분석하여 픽셀의 구조, 표면의 형태 등의 형태학적인 특성을 고려한 스무딩 과정과 필터링과정을 통하여 앤티에얼리아싱을 구현한다. 실험결과 제안하는 알고리즘이 기존의 알고리즘보다 잡음제거를 통한 우수한 앤티에얼리어싱 기법임을 확인하였다. 이 방법은 컴퓨터 그래픽분야의 앤티에얼리어싱을 구현하는데 기본적인 알고리즘으로 사용될 수 있다.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2003년도 International Meeting on Information Display
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• pp.881-884
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• 2003

We propose a new pixel structure for Active Matrix OLED (AMOLED). The proposed pixel structure can display full color images by compensating threshold voltage (Vth) variation of driving TFTs. And we obtain an improved contrast ratio(C/R) of higher than 600:1

• 한국전기전자재료학회논문지
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• 제20권11호
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• pp.983-990
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• 2007

In this study, we propose a new pixel edge shape of the fringe field switching(FFS) mode which ensures more stable movement of liquid crystal molecules and higher transmittance at the edge part. the electro optical properties were calculated 3-dimensionally using by commercially available "Techwiz LCD". From the simulation results, we showed that the dynamic stability of liquid crystal molecules was obtained in a new pixel structure. We also revealed that the transmittance of the new pixel structure increased more than 6 % compared to that of the conventional pixel structure.

• Current Optics and Photonics
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• 제7권2호
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• pp.200-206
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• 2023

Near-infrared (NIR) sensing technology using CMOS image sensors is used in many applications, including automobiles, biological inspection, surveillance, and mobile devices. An intuitive way to improve NIR sensitivity is to thicken the light absorption layer (silicon). However, thickened silicon lacks NIR sensitivity and has other disadvantages, such as diminished optical performance (e.g. crosstalk) and difficulty in processing. In this paper, a pixel structure for NIR sensing using a stacked CMOS image sensor is introduced. There are two photodetection layers, a conventional layer and a bottom photodiode, in the stacked CMOS image sensor. The bottom photodiode is used as the NIR absorption layer. Therefore, the suggested pixel structure does not change the thickness of the conventional photodiode. To verify the suggested pixel structure, sensitivity was simulated using an optical simulator. As a result, the sensitivity was improved by a maximum of 130% and 160% at wavelengths of 850 nm and 940 nm, respectively, with a pixel size of 1.2 ㎛. Therefore, the proposed pixel structure is useful for NIR sensing without thickening the silicon.

• 한국전기전자재료학회논문지
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• 제18권11호
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• pp.1033-1037
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• 2005

We have studied on the effect of the operation voltage according to the reverse twist for the different fringe field switching (FFS) structure. The FFS structure with a vertically patterned edge of the pixel electrode (VPP) has lower operation voltage comparing to the one with a horizontally patterned edge of the pixel electrode (HPP). The reason is like that the number of the pattern of the pixel edge for the VPP structure is one third comparing with the HPP structure and thus, there is small reverse twist area for the VPP structure. Actually, the reverse twist disturbs the twist of LC near adjacent active area, result that LCs near there have the unstable dynamics. That is, the operation voltage increases as the reverse twist area increases. Therefore, it is very important to design pixel electrode with a small reverse twist region for the FFS mode.

• Current Optics and Photonics
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• 제7권5호
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• pp.485-495
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• 2023

The pixel size in high-resolution complementary metal-oxide-semiconductor (CMOS) image sensors continues to shrink due to chip size limitations. However, the pixel pitch's miniaturization causes deterioration of optical performance. As one solution, a quad color filter (CF) array with pixel binning has been developed to enhance sensitivity. For high sensitivity, the microlens structure also needs to be optimized as the CF arrays change. In this paper, the covered microlens, which consist of four microlenses covered by one large microlens, are proposed for the quad CF array in the backside illumination pixel structure. To evaluate the optical performance, the suggested microlens structure was simulated from 0.5 ㎛ to 1.0 ㎛ pixels at the center and edge of the sensors. Moreover, all pixel structures were compared with and without in-pixel deep trench isolation (DTI), which works to distribute incident light uniformly into each photodiode. The suggested structure was evaluated with an optical simulation using the finite-difference time-domain method for numerical analysis of the optical characteristics. Compared to the conventional microlens, the suggested microlens show 29.1% and 33.9% maximum enhancement of sensitivity at the center and edge of the sensor, respectively. Therefore, the covered microlens demonstrated the highly sensitive image sensor with a quad CF array.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2002년도 International Meeting on Information Display
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• pp.153-156
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• 2002

We have developed a pixel structure for reflective color TFT-LCD which can display 27-color in still-image. The proposed pixel can display 3 gray scale in still image; white, black and median gray. This paper shows the concept and the driving method of the proposed pixel. Finally this paper compares power consumption and area with the Toshiba's DMOG technology.

• 센서학회지
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• 제23권2호
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• pp.87-93
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• 2014

In this paper, we propose a block-based low-power complementary metal oxide semiconductor (CMOS) image sensor (CIS) with a simple pixel structure for power efficiency. This method, which uses an additional computation circuit, makes it possible to reduce the power consumption of the pixel array. In addition, the computation circuit for a block-based CIS is very flexible for various types of pixel structures. The proposed CIS was designed and fabricated using a standard CMOS 0.18 ${\mu}m$ process, and the performance of the fabricated chip was evaluated. From a resultant image, the proposed block-based CIS can calculate a differing contrast in the block and control the operating voltage of the unit blocks. Finally, we confirmed that the power consumption in the proposed CIS with a simple pixel structure can be reduced.