A photosensitive screen that can take pictures of objects placed on its surface could be used to provide biometric identification for secure mobile e-commerce.
Toshiba, the screen’s developer, claims it can capture the detail of a human fingerprint sufficiently for it to be transmitted for authentication. The imaging display could also be used to read barcodes, capture data from a catalogue, and import route maps into a PDA from the screen of an in-car navigation system.
Toshiba has built the display into a prototype PDA, but the technology could also be adapted for mobile phones, tablet PCs and laptop computers.
In demonstrations of the technology in the US last week, the PDA screen was used to capture and display images of business cards, said Steven Vrablik, business development director for liquid crystal displays at Toshiba America Electronic Components. ‘We expect the input display technology to lead to new consumer and business applications, such as fingerprint reading,’ he added.
The prototype display, which is not yet available commercially, is an 9cm thin film transistor LCD. When an object is placed on the screen, light from the display’s backlight reflects off the object’s surface. This light is received by the photosensitive pixels making up the display. These pixels can recreate the received light, or display it, and the device records the image.
The display is only capable of recreating an actual-sized image, as the sensors do not have any zoom or focus capability, and can only capture complete images of objects small enough to fit within the screen’s surface area.
In monochrome the scanned image quality can be as high as 300 dots per inch. The imaging display can also capture colour images, but at much lower picture resolution.
The company sees this imaging display as the first step towards developing its System On Glass technology. This aims to make the screen not only a display but also a glass circuit board, enabling a wider array of functions to be built in.
LCD modules with built-in random access memory and digital analogue converters have already been created for mobile phones.