16 Oct 2002
Pressing a button toggles Sharp's latest display between 2D and 3D viewing modes.
Researchers at Sharp's European Laboratories (SLE) in the UK have developed a liquid-crystal display (LCD) that can switch seamlessly between two-dimensional and three-dimensional viewing at the push of a button. What's more, you don't need to wear special glasses to view the 3D images.
According to Grant Bourhill, SLE's research manager for imaging technology, the technology is scalable. "To date, we have developed single-user displays ranging from handheld-type displays, such as PDA's, right up to monitor size," he told Optics.org. "The first Sharp products with the 3D add-on will be available in quarter one of 2003."
The effect hinges on creating a parallax barrier. The barrier blocks the direction of light from the screen so that the left and right eyes see different images, which the brain combines and perceives as a 3D representation. The screen uses a conventional thin-film-transistor LCD for planar 2D viewing and a proprietary switching LCD to establish the parallax barrier for 3D.
According to Bourhill, viewers can electronically switch to the 3D mode simply by pressing a button on the device or on a remote control. "We also have systems where the switch is done by the software itself," he says. "For example, opening up a 3D encyclopaedia on a computer."
In order to maintain the 3D effect though, the viewer must keep their head reasonably still. "Your head cannot move to the extent where the left eye starts to see the right eye image," explains Bourhill. "This is about 30 mm of movement."
To get over this problem, Sharp has patented a so-called "sweet-spot" indicator that appears on the screen only when it is in 3D mode. This helps the user find the optimal viewing position.
Bourhill says that one of the main challenges throughout the development was keeping the cost low enough so as not to prohibit mass-market entry. He predicts that consumers wanting the 3D version will pay up to 50% more than conventional products, although this will fall with volume production.
Sharp also plans to establish a consortium of companies, such as Sony, that are involved in 3D hardware, software and contents. "I think the consortium will drive the future market and future business for this technology," said Bourhill.
Jacqueline Hewett is news reporter on Optics.org and Opto & Laser Europe magazine.