Seiko Epson takes a big leap in OLED screen technology

Could the end be nigh for plasma and LCD screens? Seiko Epson has recently announced a further development in ink-jet technology, which does away with some of the problems still dogging the much-vaunted organic light-emitting diode (OLED) display technology. In particular, Seiko Epson has signaled it is moving toward a 37-inch HD OLED screen by creating a uniform deposit of organic material while removing the uneven layering of the ink-jet method.

To date, OLED technology has been used for smaller-scale screens, due to an inability to reliably form uniform organic layers on larger panels or substrates, as they are known. Until recently the most widely used process for depositing organic materials was vacuum thermal evaporation (VTE). This method, however, is fraught with technical complications and is one of the main reasons that mass production has been hindered.

Using its Micro Piezo ink-jet technology, Epson has come up with a process that achieves vastly better accuracy in depositing organic material. Trials using the same “drop on demand” approach as an ink-jet printer were found to create uniform layers with less than 1 percent volume error. This was achieved by controlling the precise ejection of different sized droplets of ink onto a substrate and using only the required volume of material.

What could well be the next big thing in television technology has several benefits going for it. OLED televisions eliminate ghosting, are high-contrast, have a fast response time and a wide-viewing angle. They are very thin, lightweight and, as they don’t require a backlight, are less power-hungry and so environmentally kinder. Ink-jets use materials efficiently, reducing manufacturer and, ultimately, consumer cost. On the flipside, however, these screens are likely to have shorter lifespans than their predecessors.

Seiko Epson is planning to exhibit a 14-inch OLED display at the upcoming SID 2009 exhibition.

Mick Webb