07 Dec 2005
Printed information labels in shops could be about to be replaced by bistable LCDs and wireless receivers. Oliver Graydon speaks to ZBD Displays, a pioneer of the technology.
A new type of zero-power display technology that acts as a "smart electronic label" is being trialled in department stores and supermarkets in the UK this month. Designed as a dynamic alternative to traditional paper labels, the idea is the brainchild of the UK firm ZBD Displays.
Each electronic label measures about the size of a cigarette packet and features a 4.5 inch QVGA (160 × 120 pixels) bistable liquid crystal display (LCD) that only consumes power when the image is refreshed. A built-in wireless transmitter and a battery completes the unit. The attraction of the innovative labels is that they allow pricing and product information to be updated remotely and instantly at the click of a computer button via a wireless network.
The UK department store John Lewis is testing 100 of ZBD's electronic labels at its flagship store in London (Peter Jones in Sloane Square) and another unnamed store is trialling 2400 at its electrical departments across the country.
"Due to competition from the Internet and other areas, retailers want to be able to change their prices in a dynamic fashion," explained Manoj Thanigasalam, vice-president of business development at ZBD Displays. "Some of them spend up to one day a week updating paper labels, so if they can get round that it's a big plus point."
At the heart of the label is ZBD's bistable LCD technology which uses a microstructured grating surface to anchor the orientation of liquid crystal molecules without the need for external power. The result is that the display has two stable orientations for the molecules that correspond to black and white pixels. An electrical signal is only needed to change the image of the display. The technology was initially developed at DERA, the UK Government's defence R&D laboratories, before being spun out into ZBD in the summer of 2000.
By opting for a reflective design that does away with the need for a backlight and simply relies on ambient light to illuminate the display, the labels consume zero power when they are displaying a static image.
According to Thanigasalam, it costs less than £10,000 to completely kit out a store with 300 electronic labels and their support infrastructure. "Retailers are looking at a 12-18 month return on their investment," he told OLE. "We have two button cells [batteries] in the units and they last approximately 20,000 updates, which means a typical lifespan of somewhere between 5 to 10 years depending on how frequently they are updated."
Although ZBD's first electronic labels are black and white images with a QVGA resolution, the firm believes that it is possible to create colour versions. The Malvern-based venture is also planning to complement its initial product with a range of different sizes and resolutions in 2006.
As for updating the labels, although Bluetooth and Wi-Fi technologies that operate at 2.4 GHz may be the most obvious wireless communications format, ZBD has opted for a different approach that provides a range of up to 100 m.
"We decided to use an ISM band at 868 MHz for several reasons. It's license free, has a far better range, there's no risk of interference from other devices and is very power efficient," said Thanigasalam. "If we put a Wi-Fi chip in our module the battery would run out in a couple of hours."
In fact, electronic price labels could be just the beginning for ZBD's bistable technology. As displays are increasingly featuring in consumer items in the home which are permanently on (such as fridges), the need for a power efficient answer is growing in importance.
ZBD is also investigating the idea of a display that can switch between a power-saving bistable mode for static images and an active mode for animated images. In theory, such a display could boost the battery life of laptop computers or mobile phones, for example. "This is something that we are looking at but is probably 3-4 years away," said Thanigasalam.
As with all good ideas, ZBD isn't the only firm developing bistable LCD technologies. A French start-up called Nemoptic is also in on the act, as is Fujitsu which has recently licensed the technology from a US firm called Kent Display Technology (OLE September 2005 p15). Both of these firms have demonstrated colour bistable displays and are chasing the electronic signage market.
A third competitor is E Ink which has developed electrophoretic displays that also need no power to display a static image but rely on electrically charged pigment particles rather than liquid crystals. The firm recently teamed up with LG Philips to demonstrate a 10.1 inch diagonal SVGA (600 × 800 pixels) electronic paper display at the FPD International 2005 show in Japan.
The combination of all this activity means that consumers could soon be seeing zero-power displays displacing paper signage everywhere from bus shelters to advertising boards.