Seiko Epson plans to develop organic light emitting diode (OLED) technology within three years, to gain an edge in the market for screens manufactured for televisions and other entertainment applications, according to a company executive.
The Japanese manufacturer would like to develop new display panels that were technically competitive with and cheaper than current thin film transistor (TFT) liquid crystal displays (LCDs) and plasma display panels (PDPs), manager of Seiko Epson's OL Business Planning, Tetsuya Mizuno, said.
In May, Seiko Epson unveiled a prototype 40-inch OLED display, the largest OLED yet shown by any manufacturer. Its unveiling was intended to demonstrate the company's research progress and generate interest in OLED among materials manufacturers. Co-operation with these manufacturers is important if Seiko Epson is to meet its self-imposed 2007 deadline, according to Mizuno.
"Expectations were very high for a long time," he said, referring to a period nearly three years ago when many display companies began showing OLED prototypes and talking up the technology as a replacement for LCD panels in cell phones and other portable devices such as personal digital assistants (PDAs).
"However, [the technology] was very difficult to launch as a product so the market slowed down," Mizuno said.
Technological barriers to the continued development of OLED, as well as improvements in LCD design, made the new displays a less attractive alternative, he said.
Seiko Epson's current development work is designed to push past these problems, and the prototype unveiling was part of its plan to put its progress with OLED technology on show.
Currently, one of the biggest problems facing OLED technology is display life. The organic material used in the screens has a working life of between 1000 hours and 2000 hours, which at first glance, may seem more than sufficient. However, Seiko Epson thinks OLED won't be a viable replacement for thin film transistor (TFT) LCD or PDP until the lifetime reaches 10,000 hours. This is one of the areas in which the company hopes material makers will be able to aid OLED development.
With lackluster demand from the industry, some material makers had not been keen to spend time and money developing the required technology, Mizuno said.
Ever since Seiko Epson unveiled its prototype, which received strong media coverage in Japan, the company has had potential partners knocking at its door offering to help with development, he said.
"Based on the speed of development over the past three years, we think we can achieve this [within the next three years]," Mizuno said. In order to be large enough to be used as televisions, displays generally need to be between 10-inches and 40-inches. Seiko Epson, more so than other companies, has met that challenge head on. When the company unveiled its 40-inch prototype, South Korea's Samsung had just announced a prototype 17-inch model, while most other companies have yet to break the 10-inch mark.
The production method for the new display is based on a modification of ink-jet printing technology. This is an area where Seiko Epson has considerable experience. The manufacturing method involves building the base of the display on a glass substrate and then using an ink-jet head to deposit exactly the right amount of a light emitting polymer (LEP) ink into dot spaces on the display.
The head used for the work is similar to those used in desktop ink-jet printers, although it is more accurate in aiming the jet of ink and also at dispensing the correct amount, according to Shoichi Lino, division manager of the company's OLED technological development division.
Commercial ink-jet printing technology can be used to print up to 120cm x 82cm and to a resolution of 1440 dots per inch. The related system being used by Seiko Epson was already suitable for large size, high-definition displays, he said.
"OLED has the potential to compete with, or replace LCD or PDP [in some applications]," he said.
Seiko Epson is looking at the portion of the display market with screen sizes of between 10-inches and 40-inches, an area currently dominated by cathode ray tube (CRT) or LCD-based products.
The focus on the entertainment sector is partly because OLED has advantages over LCDs when it comes to displaying fast moving images, according to Lino.
In addition to televisions in the living room, Seiko Epson is also considering displays suitable for mobile TVs, car multimedia products and personal TVs such as the secondary sets in many houses.
On price, the company is confident that OLED technology will be competitive, according to Lino.
"It has to be if OLED is to become a replacement for LCD," he said.
To date Seiko Epson has produced three prototype displays. The 40-inch model unveiled in May had widescreen XGA resolution (1280 RGB pixels by 768 pixels) and a pixel density of 38 pixels per inch (pp1), a 12.5-inch model has VGA resolution (640 RGB pixels by 480 pixels) and a pixel density of 64ppi and a 2.1-inch model had a 144 RGB pixel by 176 pixel resolution and a pixel density of 130ppi, the company said.