I. Description and Evolution of screen technology
The traditional cathode ray tube (CRT), had been a dominant design for a long time; however, in the last six years a shift in consumer preference for slimmer screen designs, less power consumption, and improved picture quality has been driving the demand for FPD technologies.
Discovery of the liquid crystal phenomenon dates back to 1888 by H. Reinitzer. Liquid crystal is an organic substance that has both solid crystalline and liquid characteristics within certain temperature ranges. In 1968, Williams of RCA Corporation discovered that the way light passes through liquid crystal changes when the liquid is charged with electricity. Five years later, Heilmeyer and his colleagues applied this property in a display device. In 1973, Sharp began producing the world's first mass-produced LCDs for calculators based on dynamic scattering mode technology , which suffered from low-resolution, monochrome colour, and poor viewing angles. Even with these technical shortfalls, the benefits of a small form-factor (tubeless unlike CRTs) and low power consumption made it ideal for portable applications (e.g. calculators and wristwatches). By the 1990's, twisted nematic (TN) technology (Exhibit 1-2) had proven to be reliable and advances in the manufacturing process allowed TN LCD panels to be produced at lower costs. By 1994, LCD became the most popular flat panel display with sales of $4.2 billion (Exhibit 1-3). A key driver for this was the expanded applicability of LCD into various screen applications due to improvements in resolution and brightness (e.g. computer-screens, televisions, handheld devices, and mobile phones). With higher levels of resolution and brightness combined in a smaller form-factor, increased demand in portable applications further fueled investments into LCD development, which led to further improvements in miniaturization and a better understanding of the physics behind the technology.
While development of the LCD technology had started, a self-emissive FPD technology called plasma was invented by researchers from the University of Illinois in 1964. Plasma screens are a network of red, green and blue phosphors mounted between two thin layers of glass. When charged by electrons, these phosphors emit UV light. Early versions of Plasma Display Panels (PDPs) had several limitations: low contrast in high ambient light (non-sunlight readable), low phosphor efficiency resulting to high power consumption and heat generation, and short panel life. Over time, manufacturers improved on these technological limitations. In the 1990’s, color display panels were introduced with the development of photo-luminescent phosphor materials that were absent from the monochrome display panels. In the late 1990’s, Fujitsu improved the contrast ratio from 70:1 to 400:1 with a new driver technology and started manufacturing high volumes of color PDP lines (digital TV) for consumer markets. As a result of continued innovations by several manufacturers, contrast ratio has improved up to 10,000:1. Today’s PDP versions typically have a panel life of 60,000 hours . By 1998, the worldwide sales of PDPs reached $394 million, nearly double of that in 1993 (Exhibit 1-3). (Exhibit 1-4) shows the 40-year evolution of PDP technology. Although widespread adoption has progressed at a relatively slow rate, PDPs achieved a market foothold. (need FPD shipment data to determine current market share of PDPs vs LCDs)
In examining the performance evolution of LCDs and PDPs, two dimensions - resolution and brightness - were taken for comparison. Contrast ratios are not a reliable indicator as they can...