Local control technology of green displays in South Korea and Taiwan

Walking in the "FPD International 2008" exhibition venue, "Green (green)," the words continue to come into view. It can be felt that the company's enthusiasm for the environmental protection measures represented by low consumption of electricity is increasing day by day.

First of all, the author interviewed the "Green" technology in the exhibition area of Korea and Taiwan. No matter which booth, the most prominent is the LCD TV with low consumption of electrochemical technology.

LCD TV as a LCD panel with low energy consumption of the method, the company uses a backlight Dimming (Local) technology. The technology is based on the display image, according to different regions of the backlight to illuminate the parts of the control, not only can reduce power consumption, but also can improve the contrast, etc..

Although some liquid crystal panels have been introduced into the local control technology, but the company in this exhibition is the propaganda of the technology evolution".

Power consumption reduced by half

South Korea's Samsung Electronics (Samsung ELectronics) exhibited the use of "3-Way Dimming" local control technology LCD panel (Figure 1). This is a local control technology using RGB3 color LED implementation. In the past, most of the local control techniques use white LED, because the use of RGB LED can improve the efficiency of the use of light in the process of color reproduction. According to the company, compared with the use of white LED local control technology, power consumption can be reduced by about 50%. For example, in the 46 inch Full HD (Full HD) on the film, only about 80W. The white LED is about 188W.

South Korea's LG Display on the display of the "Advanced Local Dimming" advanced local control technology. The technology through the efforts to achieve the optimization of the driver and other measures, the average power consumption reduced to 50%. The display of the 47 inch panel on the screen shows that, compared with the previous 169W consumption of the product, the premium version is only about 50W (Figure 2).

At the same time to achieve ultra-thin and low power consumption

Local control technology from the principle, can only be realized in the straight down backlight structure, therefore, it is more difficult to achieve thinner than the use of end face backlight. Taiwan Chi Mei Electronics (Chi Mei Optoelectronics, CMO) to solve this problem. The company exhibited a 55 inch LCD panel with a thickness of only 9.9mm in the case of a local control technique (Figure 3). Thickness reduced to about half of the previous.

Since the backlight is thinner and the light source is closer to the panel, it is necessary to increase the number of LED so that each LED is not conspicuous. According to the company, when the thickness of 20mm configuration 5500 LED, thickness of 9.9mm, you must configure the 21 thousand and 950 LED. It is quite difficult to arrange so many LED. By optimizing the number of LED, as well as the use of special LED board to achieve a thin.

Exhibit power consumption varies with the display screen, but in the range of 62 to 90W. Without introducing local control technology for 200W, it is clear that the exhibits at the same time to achieve the ultra-thin, as well as the previous half of the low energy consumption.

Figure 1: Samsung Electronics Using 3-Way Dimming technology LCD panel

Figure 2:LG Display company Advanced Local Dimming"

Figure 3: 9.9mm thickness and low power consumption of CMO 55 inch LCD panel

Source: Nikkei BP