Low-power consumption STN transflective color LCD panel module that conquered mobile phone market

November 1999


Drive method: Passive matrix type
Display mode: STN transflective color
Dimensions: 34.7 x 40 mm
Pixel count: 96 x 120 dots
Display colors: 256 colors
Power consumption: 1.2 mW (420µA x 3)

The ECM-A1192 was an STN (super-twisted nematic a type of liquid crystal) transflective color LCD panel module developed to meet demand for high- definition color and low power consumption. This panel module went into full production in November 1999, just in time for the Japanese boom in internet- and email-ready mobile phones. The ECM-A1192 employed a transflective panel structure so that in bright environments it worked in reflective mode and did not require any backlighting, while in dark environments, it worked as a transmissive display, using a white LED backlight. In addition, the panel took advantage of partial drive technology that lowered power consumption to just 1.2 mW for partial display functionality when the phone was in receive-ready mode.

Epson's engineers scored another success in their design of the LCD panel's inner reflective layer, which uses reflective layer technology called SPD (Single Polarizer Display) to reduce parallax and provide a display with higher contrast and better color reproduction. The beautiful color display in mobile phones that used this panel helped those phones become a big hit and enabled Epson to ship more than 2,740,000 of these panels so far. This heped to firmly establishing the company's position as a leading manufacturer of color LCD panels for mobile phones. Moreover, Epson's development of this color STN LCD panel laid the foundation for its development of the MD19SBT, a mobile-digital thim-film-diode (MD-TFD) active- matrix color panel for such phones.