Pixtronix has finished development of its new MEMS based PerfectLight DMS (Digital Micro Shutter) display technology. The display, demonstrated at this months SID Display Week 2009, delivers exactly what both consumers and manufacturers are looking for; significant energy savings (75 percent) without compromising video quality.

Pixtronix was established in 2005 and is led by experts in the fields of displays, optics and MEMS (Micro-electromechanical systems). Having completed development of a PerfectLight DMS display prototype, the company is now searching for manufacturing partners. While initially targeting smaller display sizes for portable multimedia devices, Pixtronix can scale the display sizes to suit large screen products such as HDTVs.

Pixtronix’s PerfectLight DMS (Digital Micro Shutter) display technology has been designed to combine high video quality with low power consumption for display sizes from mobile devices through to HD televisions. Performance figures include 105% (of NTSC, CIE 1931) color gamut, 24-bit color depth, 1,000:1 contrast ratio and 170 degree viewing angle with a power consumption only one quarter (25 percent) that for TFT-LCD displays.

Cleverly Pixtronix’s engineers have developed their technology based on a similar architecture to that of an LCD panel (hence LCD 2.0!) except for using micro (MEMS) shutters instead of liquid crystals. The DMS display system is based on sequentially flooding the display with red, green, and blue light from LEDs while using the MEMS shutters to modulate the light and produce a full-color image. MEMS have already established their robustness and reliability in display technology through technologies such as Texas Instrument’s DLP micro mirror chips used in projectors.

Key Elements of DMS Display Technology

• Digital MEMS micro shutter element at the heart of each pixel. It is a laterally translating (moving) element which is supported on a patented dual compliant zipping actuator. Use of micro shutters frees DMS displays from using the polarizers, filters and liquid crystals of current LCD display technologies. The polarizers can reduce light intensity by 50 percent and color filters reduce it even further.
• Field Sequential Color (FSC) use is enabled by the MEMS shutters through the rapid color change frequencies of about 1kHZ (1,000 operations per second) achieved. Pixtronix have developed some innovative algorithms for achieving deep, rich colors without image artefacts.
• Proprietary optical architecture including a light recycling backlight. Through a combination of waveguide and mirrored surfaces the light in the backlight is contained to deliver 60 percent of the light from the backlight which about 10X more output than a conventional LCD display (6 to 8 percent). This is the primary source of power consumption reduction of the DMS display technology.
• Use of energy-efficient LED lightsources
• A digital backplane circuit which decouples the functions of actuation and information exchange. This makes possible time division gray scale with color change frequencies in excess of 1 kHz while minimizing drive power.

From an engineering background, what impresses about Pixtronic’s new display technology is the cost savings promised by its having been designed with minimization of manufacturing costs in mind. Manufacturing can use existing TFT-LCD factory equipment and processes and higher yields can be achieved through the wide manufacturing tolerances applicable.

Resources

Take a look at Pixtronix’s video introduction to the PerfectLight Display’s impressive image quality and ultra-low power consumption.

If you would like to gain an idea of what MEMS is about have a look at this introductory video from the MEMS Industry Group. Is has some interesting shots of another MEMS display technology, DLP, in action.