Cathode Ray Tube is the most common display in the world. It has been developed for 80 years and its technology is well developed. However, due to the display theory of CRT, it is heavy and large when the display size increases. Thus the conventional size of CRT in the market is limited to about 30 inch, and the largest one is about 50 inch, which is extremely heavy and large. The flickering effect and radiation issue also are taken notice by consumers. Due to the disadvantages listed above, further development of CRT display is limited. Thus in recent years, people pay attention on the Flat Panel Display (FPD).
Plasma display panels are one of the leading candidates in the competition for large-size, high-brightness, high contrast ratio flat panel displays, suitable for high definition television (HDTV) wall-mounted monitors. Their advantages include large screen size, wide viewing angle, low weight, small thickness and simple manufacturing process for fabrication, as shown in Fig 1.1. The plasma display panel was invented at the University of Illinois at Urbana-Champaign by Donald L. Bitzer and H. Gene Slottow in 1964 for the PLATO Computer System. In 1983, IBM developed a 19" orange on black monochrome display. In 1992, Fujitsu introduced the world's first 21-inch full color display. In early years, PDP application was limited to industry due to its high price. Plasma's relatively large screen size and thin profile made the displays attractive for lobbies and stock exchanges. In 1997 Pioneer started selling the first plasma television to the public. With the development and manufacture of many companies, the size of PDP grows bigger and bigger. In recent years, the improvement of technology makes PDP great image quality, which approaches the traditional CRT.
Fig. 1.1 Advantages of Plasma Display
Due to the theory and manufacturing process of AC-PDP, it is suitable to make large size flat panel display. Screen sizes have increased since the Fujitsu’s 21 inch display in 1992. Right now the conventional size is between 42 inch to 55 inch, and 71 inch size is already in production. The largest plasma display in the world was shown at the CES (Consumer Electronics Show) in Las Vegas in 2006. It is 103 inch and was made by Matsushita Electrical Industries (Panasonic), as shown in Fig. 1.2.
Fig 1.2 The world’s largest 103 inch Plasma Display made by Matsushita
Plasma displays have high contrast ratio, wide viewing angle, fast response time, good color performance and can be produced in very large sizes up to 103 inches.
High dark-room contrast makes the PDP suitable for watching movies. Since each pixel is lighted individually, the image is very bright and looks good from almost every angle. The power consumption per square meter of plasma displays is as much as a CRT TV. Real life measurements indicate 150 Watts for a 50 inch PDP. The lifetime of the new generation plasma displays is about 60,000 hours. Precisely, it is the estimated half life of the PDP. Half life is the point where the brightness has degraded to half of its original value, which is considered the end of the life of the display. So a plasma display will last approximately 20 years if it is viewed 8 hours a day.
Fig 1.3 The application of Plasma Display
The superior brightness and wider viewing angle of color plasma displays, when compared to LCD televisions, made them one of the most popular forms of display for HDTV. Right now the TFT-LCD dominates the market below 40 inch while PDP dominates that above 40 inch. With the competition of the large size TFT-LCD, it is very important for PDP manufacturers to improve luminous efficiency, solve image quality issue and lower the price to occupy the market of large size flat panel display.
In 2005 the cost has come down to NT$50000 or less for the popular 42 inch diagonal size, making it very attractive for home-theatre use. In US, many of the retailers reported that plasma TVs were among the hottest selling items for Christmas season in 2005. As of early 2006, sales of plasma TVs and LCD TVs combined exceeded sales of CRT TVs for the first time.
Recent progress for PDP technology development and manufacturing has been remarkably improved. However, there are many problems that need to be resolved.
One of the most critical issues in PDP research is the improvement of the luminance and luminous efficiency of the display, which are low compared to conventional
cathode ray tube displays (CRTs). Another important problem is the relatively high operating voltages which increase the cost of the electronics and consequently the overall cost of the display. Finally there are some image quality issue like dynamic false contour[1] and image sticking phenomenon[2].
This research will focus on two major aspects. One is the degradation and contaminations of the MgO thin films caused by phosphors. The other is the influence of the noble gas mixture on the image sticking phenomenon. In Chapter 2, the principles of PDP will be introduced. Recent research about image sticking phenomenon, MgO thin film, Phosphor and gas mixture of PDP will be reviewed in Chapter 3. Chapter 4 will introduce the experiment setup and investigation method.
The result in this study will be discussed in Chapter 5. Finally, the conclusion will be given in Chapter 6.