The Prysm company has developed a new technology, calledlaser phosphor screen (LPD), which possesses the perfect combination ofimage quality, low cost and energy savingto compete with today’s liquid crystal displays (LCD).
According to Roger Hajjar, the company’s chief technology officer, an LPD displayconsumes a quarter of the energy of a liquid crystal display with the same brightness, and about a tenth of the energy of a plasma screen. “On the other screens the light source is on most of the time and it takes a certain amount of power even to keep the screen black,” says Hajjar. With LPDs, he adds,lasers stop working when screen is black, which translates into energy savings.
The mechanism that supports a laser screen is quite simple. Beams of light from several ultraviolet lasers are directed by a group of movable mirrors on a screen made of a materialglass-plastic hybrid with colored phosphor strips. The laser draws an image on the screen by scanning each of the lines from top to bottom. The energy of the laser light activates the phosphor, whichemits photonsand produces an image.
Hajjar anticipates that the LPDs will soon be used as advertising displays in cities, airports, shopping malls and soccer stadiums. In addition, they could also replace the LED screens used to display information on stock markets, data on temperature and concentration of atmospheric gases in weather stations or information on road traffic.
