Prysm's Laser Phosphor Display

Prysm's Laser Phosphor Display

A single unit or "tile" has a 15-by-20-inch display and is 18 inches deep.

Photo courtesy of Prysm

The Guts of an LPD

The Guts of an LPD

Inside Prysm's device is an array of lasers that shoot a beam at a spinning mirror. Directed by a series of fixed mirrors, the light beam scans across the phosphor-covered front panel hundreds of times per second.

Image courtesy of Prysm

GE Display Wall

GE Display Wall

General Electric installed a 58-foot Prysm display wall at an energy center in Toronto.

Image courtesy of Prysm

The IAC Wall

The IAC Wall

The largest Prysm installation is a 120-foot wall in the lobby of the IAC building in Manhattan.

Image courtesy of Prysm

The IAC Wall

The IAC Wall

IAC uses the wall to show a rotating variety of media.

Image courtesy of Prysm

Retail Imagery

Retail Imagery

This department store in London uses a wall of Prysm displays to enhance its shopping space.

Image courtesy of Prysm

First-Generation LPD Wall

First-Generation LPD Wall

Vice president of marketing Tim Messegee in Prysm's showroom. This wall consists of first-generation units.

Photo by Wade Roush

Stackable and Touchable

Stackable and Touchable

Prysm's LPDs can be arranged in any configuration. Here, five tiles are stacked vertically, with a touch screen layer at the front that allows interactivity.

Photo by Wade Roush

The Prototype Conference Room Wall

The Prototype Conference Room Wall

Prysm installed a five-by-four array of second-generation displays in its own board room.

Photo by Wade Roush

Display Cabinet

Display Cabinet

The conference-room display wall is housed in a modular cabinet about 18 inches deep.

Photo by Wade Roush

Larger Conference Room Video Wall

Larger Conference Room Video Wall

One customer built an entire wall around this nine-by-four grid of displays.

Image courtesy of Prysm

Prysm in Sweden

Prysm in Sweden

This Prysm video wall is the centerpiece of a lecture hall at an academic institute in Stockholm.

Image courtesy of Prysm

One sign that your company has arrived is that you can afford telepresence suites from Cisco or Polycom—you know, those rooms equipped with a trio of 1080p flat-panel displays and special cameras, microphones, and lighting so that chief executives in New York can see tiny droplets of sweat on the faces of vice presidents in Los Angeles.

The cost of building and running these rooms can easily run into the millions of dollars. They may take the place of private jets, but they’re not much cheaper.

Now Prysm, a San Jose, CA- and Concord, MA-based display company I’ve been following since 2010, is offering an alternative that could put big-screen, two-way video collaboration within the reach of many more organizations. An existing conference room can be equipped with a five-by-fifteen-foot Prysm display wall for about $250,000, executives at the company say.

“Those big, dedicated telepresence rooms—that market still exists but it’s on a downward trend,” Tim Messegee, Prysm’s vice president of marketing, told me as we sat yesterday in Prysm’s own board room, which has a 117-inch video wall at one end. “What customers are asking for are spaces that are much more versatile. In here, you can have a staff meeting. The CEO can have a board meeting. Engineers can meet across three or four sites. You can do telepresence and share content on the same screen.”

Prysm is an eight-year-old startup built around an unusual device called a laser phosphor display, or LPD. To commercialize the machines, which combine technologies from Blu-ray players, laser printers, and classic cathode ray tubes, the company has hired 190 people and raised $148 million in venture backing from Artiman Ventures and Partech International. But to achieve high growth, it needs to find a market that’s bigger than the first one it pursued: large display walls for public environments such as retail stores and corporate lobbies.

For the lobby of IAC’s Manhattan skyscraper, Prysm built a display that’s 10 feet high and 120 feet long; it functions mainly as a canvas for environmental art. General Electric installed 58-foot wall, in a semicircular configuration, at its Grid IQ Research & Collaboration Centre in Toronto.

But there are only so many customers for these kinds of installations. Companies that want to outfit their conference rooms with “collaboration walls” could provide a much larger market.

Messegee thinks the potential customers for such walls number in the thousands. He predicts that by the end of 2014, 70 percent of the company’s business will come from these office installations.

“These massive walls served their purpose, and we are happy we did all of that,” says Roger Hajjar, Prysm’s co-founder and chief technology officer. “But we started to get calls from CIOs saying, ‘We have these $700,0000 telepresence suites so you can look at the guy on the other side, but then to share a presentation they turn on a projector, and the images don’t look good. Can you guys converge the two together?’”

A few buyers of Prysm’s first-generation displays, which debuted in 2010, used them to build collaboration walls. But the company didn’t push that application because it didn’t feel the individual displays had the required resolution and crispness.

The company’s second-generation displays, announced this May, have 77 percent greater resolution and a 50 percent faster refresh rate. Those are the ones being shipped to corporate customers now. The first conference rooms with the new displays should be ready by September.

“Customers had started deploying our old models into conference rooms,” Hajjar says. “But we found we had to improve the resolution to get that immersive feeling.”

Prysm’s laser phosphor displays aren’t anything like the flat-panel LCD, plasma, and OLED displays that dominate Best Buy showrooms. Inside a Prysm display, 20 blue lasers shoot light beams at a spinning mirror, which traces the beams across a panel covered with photosensitive phosphors.

This design means the image can extend to the very edge of the display—no frame or bezel is required. And that means the individual 15-by-20-inch displays can be stacked into a grid of arbitrary size. Computers can spread an image across the displays with no noticeable gap. (The seams between screens are less than one pixel wide, and are virtually invisible if you’re more than 20 feet away.)

The key to building Prysm’s second-generation device, Hajjar explains, was changing the optics and mirrors to eliminate some distortion in the way video images were projected. Under the previous design, the scan lines became rounder and rounder as they approached the bottom of the phosphor panel. The company corrected for this using software, so images themselves weren’t distorted, but it meant some resolution was sacrificed.

Now all the scan lines are straight, meaning Prysm can take advantage of all 320 rows of phosphors printed on the panels. To be exact: the pixel count has been raised from 320×240 in the first-generation LPD to 427×320 in the second-generation display, without changing the way the panels themselves are manufactured.

For the IAC wall, Prysm built a grid of 432 displays (six high and 72 long). But for a conference room video wall, the most popular choices are a much smaller five-by-four grid or a nine-by-four grid, Messegee says. A five-by-four grid housed in a cabinet in Prysm’s board room was the prototype.

On a nine-by-four grid, there’s room for two HD-resolution images side by side. Customers commonly use one side to show participants in a video conference, and the other side to show visual materials such as slide decks, Messegee says. The lasers inside don’t use much power, so the whole grid can run off one wall plug, and they don’t generate much heat, so the video walls don’t require any special cooling.

While the giant, public LPD installations have boosted Prysm’s reputation, they haven’t necessarily boosted its bottom line as much as the company and its investors would like. Hence the move into video conferencing.

“When customers started pushing into these beauty walls, for digital signage, we went there with them,” Hajjar says. “We never imagined they would grow that big and that beautiful. But there are 600,000 conference rooms in the U.S. We are not abandoning the marquee projects—-but we wanted to go into a more scalable market.”

Wade Roush is a contributing editor at Xconomy.