Prysm Hopes Laser-Driven Screens Will Outshine LCD, LED Displays

1/13/10Follow @wroush

If you’re seeing electronic displays on every wall, window, billboard, and passing dirigible, it’s a sure sign that you’re stuck in a science-fiction movie. While a few real-world destinations like New York’s Times Square and Tokyo’s Ginza district are plastered with outdoor displays, such technology is still too expensive and electricity-hogging to put everywhere.

But this might not be true forever. In fact, Prysm, a San Jose, CA, startup that came out of stealth mode yesterday, is working to ease the biggest limitations on large-screen displays, especially their power requirements. The company says that screens using its new laser phosphor display (LPD) technology suck up only one-quarter as much electricity as screens using today’s dominant liquid-crystal display (LCD) or light-emitting diode (LED) technologies.

Moreover, Prysm’s LPD screens—which the startup plans to manufacture at a plant in Concord, MA—can be built in any size or shape, from square tiles to long, thin ribbons, meaning they could turn up almost anywhere someone wants to convey information or advertising, day or night. “We can make it as big and bright as you can imagine,” says Roger Hajjar, Prysm’s co-founder and chief technology officer and the primary inventor of the company’s LPD technology. “That’s the goodness here—the size and brightness are scalable. If you need more brightness, you just add more laser power.”

Prysm displays in a theaterHajjar and Prysm CEO Amit Jain, who have been friends since their undergraduate days at Boston University, co-founded the startup under the stealth name Spudnik back in 2005, with venture funding from Artiman Ventures of East Palo Alto, CA, and Partech International of San Francisco. Hajjar says large LPD-based screens—which actually have more in common with old-fashioned cathode ray tubes (CRTs) than they do with LCDs—became practical for the first time in the 2000s thanks to the development of new phosphor materials by the LED industry and the increasing power and efficiency (and declining cost) of laser-light sources. Unlike many hardware startups, Prysm won’t merely license the intellectual property it has developed to other equipment makers, but plans to manufacture and sell LPD products under its own brand.

The company isn’t saying yet exactly which applications or markets it will pursue first, and it’s only showing off its prototype displays in private, invitation-only settings such as a booth at the Integrated Systems Europe audio-video trade show in Amsterdam next month. But a glimpse at the Prysm website shows where the company’s thoughts are heading. In Prysm’s glossy version of the future, LPDs will light up theaters, casinos, trade shows, stadiums, shopping malls, broadcast studios, train stations, airports, command centers, financial exchanges, hotel lobbies, museums, even churches.

LPD screens may initially cost more to install than LCD or LED screens, but Prysm vice president of sales and marketing Dana Corey says they’ll cost far less to operate, since they use less power and don’t contain lamps that will eventually blow out and need replacing. LPD screens also boast higher resolution than LCD or LED-based screens, don’t suffer from the motion blur that can afflict these technologies, and can be viewed from wider angles, Corey says.

“Over time LPD will expand to fill in the gaps left by those other technologies, in situations where people want a wide viewing angle, low power consumption, or high brightness and resolution,” says Corey.

From what Prysm is saying about its technology—which isn’t a lot, yet—the guts of an LPD screen sound remarkably simple. One of the most expensive components of a flat-panel LCD screen like the one in your HDTV set, desktop monitor, laptop, or mobile phone, is the glass plane of transistors that drive each pixel. Laser phosphor displays dispense with all that. As the name suggests, the devices are driven by a laser that turns on and off at precise times as its beam sweeps across a patterned array of phosphor stripes, one stripe at a time.

Conceptually, this is very similar to the way old-fashioned televisions worked. In a CRT, electromagnets control an electron beam that sweeps across a field of electro-sensitive phosphors. The main differences between CRTs and LPDs, according to Jain and Hajjar, are that the beam in an LPD is made of coherent light, rather than electrons; that the beam is directed by a rapidly rotating “scanning mirror,” rather than magnets; and that the phosphors are photo-sensitive, rather than electro-sensitive.

Laser Phosphor Display diagram“There’s a similarity in many ways, concept-wise, to CRTs,” says Jain. “But CRTs use huge amounts of energy. This is better, because a laser is the most efficient optical device known to mankind.”

The phosphor-covered screens are the component that Prysm plans to manufacture in Massachusetts, at a West Concord facility that formerly housed a maker of scanning electron microscopes. The plant already has 40 employees and will hire another 40 this year, the company says.

Corey says this week’s announcement represents merely the startup’s coming out, and that more information about Prysm’s technology and its product roadmap will be made public “shortly.” Prysm hasn’t said how much money it has raised, who its backers are (beyond Artiman and Partech, whom Jain calls “the key original investors”), or who it’s showing its technology to.

“We are no different from any other venture-funded stealth mode company in Silicon Valley, in that we wanted to stay in stealth for as many years as possible while we went from initial innovation to concept development to product development,” says Jain. “The only difference is that from very early on we were not just in one location.” In addition to its San Jose headquarters, Prysm has a facility in Bangalore, India, and has had a development center in Concord for several years (at a different address from the new screen manufacturing facility).

For Jain and Hajjar, Prysm is almost a third act: in addition to graduating together from Boston University’s College of Engineering, they co-founded and served as CEO and CTO, respectively, at Versatile Optical Networks, a San Jose-based maker of optoelectronic components for networking equipment. Vitesse Semiconductor (NASDAQ: VTSS) bought Versatile Optical Networks in 2001 for almost $250 million.

According to Hajjar, there’s no fundamental reason that LPD technology couldn’t be used in small displays like those in laptops and handhelds. But that might not be practical from a cost standpoint until the company can manufacture the devices on a large scale. In the meantime, the company will probably go after the market for much larger displays—those so big that owners need to take into account their expenses over time, including electricity and repairs.

Says Corey, “When you don’t have lamps that die at a certain time, when you’re not using thousands of watts per square meter, those add up to big dollars.”

[Update, January 20, 2010: Freelancer Kate Greene takes a takes a more technical look at Prysm over at Technology Review's website today.]

Wade Roush is a contributing editor at Xconomy. Follow @wroush

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