Yun-Jae Park

40.1: Distinguished Contributed Paper: Integrated Amorphous Silicon Color Sensor on LCD Panel for LED Backlight Feedback Control System

In this paper, we present the feasibility of an optical color sensing feedback system for an LED backlight by integrating the amorphous silicon color sensor onto the LCD panel. To improve the well-known photoconductivity degradation of amorphous silicon, a new LASER immersion treatment has been applied. The integrated color sensor optical feedback controlled LED backlighting system improved the color variation to less than 0.008 Δu‘v’ (CIE1976) compared with 0.025 for an open loop system over the temperature range of 42°C to 76°C.

P-78: A Thermally Adaptive Response Time Compensation System for LCD Panels

This paper presents thermally adaptive driving (TAD) technology for response time compensation (RTC) of an LCD with an integrated sensor. The TAD is comprised of analog sensor signal conditioning and a digital feedback algorithm. The integrated thermal sensor provides accurate temperature measurement of the liquid crystal layer. The TAD controller has an 8-step look-up-table (LUT), and compensates response time based on the panel temperature. The TAD system reduces response time by nearly 50% over the temperature range 0 ° −; 60 °C.

LED backlight driving system with local dimming and scanning driver IC

Abstract— Novel LED backlight driving technology with a fully embedded LED driver IC is presented. This driving system and IC feature a high speed reduced swing differential signaling (RSDS) interface, an independent PWM controller with high-resolution programming, and embedded scan logic. To attain high efficiency from the boost converter, highly advanced dynamic headroom control technology has been implemented onto the IC. The embedded current boosting function showed almost no brightness reduction when operated in scanning mode. The scanning function of the system improved motion blur values 26–44% compared to that of a non-scanning LCD panel.

50.1: Advanced Local Dimming and Scanning LED Backlight Driving System Using Novel Driver IC

This paper presents novel LED backlight driving technology with a fully embedded LED driver LC. This driving system and IC feature a high speed Reduced Swing Differential Signaling (RSDS) interface, an independent PWM controller with high resolution programming, and embedded scan logic. To get high efficiency from the boost converter, highly advanced dynamic headroom control technology has been implemented onto the IC. The embedded current boosting function showed almost no brightness reduction when operated in scanning mode. The scanning function of the system improved motion blur scores about 30% compared with a non-scanning LCD panel.

38.1: Integrated Thermal Sensor on LCD for Temperature Compensation System

This paper presents a thermal sensor which has been integrated onto an LCD. The sensor uses metal (Mo/Al) film as a temperature detection layer, and its fabrication requires no manufacturing process changes. The sensor shows very good linearity, sensitivity and reliability. Used with a feedback system, the thermal sensor resulted in flicker reduction of nearly 70% over the temperature range 10 °C to 70 °C.