First double-sided LCD launched

Display Technology, Samsung's UK TFT distributor and Value Added Reseller, announces Samsung's first truly double-sided LCD

Display Technology UK and Samsung Electronics Co., Ltd., provider of thin-film transistor, liquid crystal display (TFT-LCD) panels announces that Samsung has created the first LCD panel that can produce independent images on each side of a mobile LCD display. Samsung's new double-sided LCD can show two entirely different pictures or sets of visual data simultaneously on the front and back of the same screen.  Other conventional double-sided LCDs can only show a reverse image of the same video data. This new development will replace two display panels with one, thereby reducing overall thickness of mobile products by at least 1mm.

Display Technology's Product manager Nick Shaw, said, "this new double-sided mobile display demonstrates Samsung's commitment to equip customers with advanced display technology that accelerates the trend toward slimmer mobile products, but also their commitment to the highest quality TFT displays right up to 82" and larger!"

The breakthrough LCD product makes use of Samsung's new double-gate, thin-film transistor (TFT) architecture. TFT gates are electronic components that convert the necessary voltage at the pixel level, which controls the liquid crystal alignment needed to reproduce on-screen images. Samsung's new double-sided LCD has two gates that operate each pixel instead of one, so the screen on the front can display different images than the one on the back. The double-sided display makes use of Samsung's proprietary Amorphous Silicon Gate (ASG) technology, which accommodates the increased number of TFT gates without increasing the size of the driver integrated circuits.  Driver-ICs typically increase in size when more TFT gates are used.

The new Samsung mobile display requires only one backlight, while competitive double-screen LCDs require two. One side of the panel operates in a transmissive mode, while the other operates in a reflective mode. By using a unique reflective design that utilizes the light trapped in the opposing screen's transmissive mode, the reflective mode does not solely rely on external light sources such as the sun.

The double-sided, dual image LCD's efficient use of light to display images in both transmissive and reflective modes promotes slimmer, more cost-effective products.

The new double-sided LCD is 2.6mm thick and 2.22" wide, with QVGA (240 x 320 pixel) resolution, and has brightness values of 250 nits for the front and 100 nits for the rear display. It will be exhibited at the Consumer Electronics Show, which opens in Las Vegas on January 8.

 
[ Main Specifications ]

Main Screen Second-screen
Display size 2.22" 2.22"
Resolution qVGA (240 x 320) qVGA (240 x 320)
Mode a-Si a-Si
Display type transmissive reflective
Brightness 250 nit 100 nit
Colors 265K 265K
Color saturation 60% 10%
Module thickness 2.6mm

[ Reference Data ]

- 1 pixel, 2 transistors
A pixel design that allows separate control of the liquid crystal on the transmissive and reflective sides, enabling both sides to display separately.

-  Double gates
The gate is a transistor element to which voltage is applied to turn on or off the circuit that provides the signal needed to drive the LCD. Normally, one circuit is needed for every pixel to make a single screen function, but Samsung's new double-screen LCD has two gates to control each pixel, a necessary condition for allowing the same pixel to be used for two different screens.

- Resolution formats for small and mid-sized LCDs
qqVGA: 128 pixels horizontal by 160 rows vertical
qCIF: 176 pixels horizontal by 220 rows vertical
qVGA: 240 pixels horizontal by 320 rows vertical
qSVGA: 300 pixels horizontal by 400 rows vertical
VGA: 480 pixels horizontal by 640 rows vertical

-  Amorphous silicon (a-Si)
Non-crystalline form of silicon

-  Transmissive mode
Transmissive mode uses a backlight through the liquid crystal cells to display the images to the viewer.

-  Reflective mode
Reflective mode uses external light such as the sun to display the images to the viewer.

-  Nit
An abbreviation for the measure of brightness, also referred to as "candela per square meter" or cd/m2.