When you think of Concord, MA, you’re more likely to visualize Revolutionary War skirmishes or Thoreau’s cabin on Walden Pond than factories full of complex machinery. But in fact, Concord was once a major hub of the clockmaking industry—in 1800 there were at least seven well-known clockmakers in the city, along with a network of suppliers including brass foundries, iron forges, wire mills, and cabinet builders. And as I learned during a recent visit to display maker Prysm, whose facility sits just across an abandoned railroad right-of-way from the Massachusetts Correctional Institute, the manufacturing spirit is alive and well in Concord.
At the core of Prysm’s plant—in a clean room that I was only allowed to visit after putting on a gown, shoe covers, and a hairnet—are four large screenprinting machines that are in nearly continuous operation, churning out the rubbery layers of phosphor material that make up the heart of Prysm’s displays. The way the company’s engineers explain it, the machines work just like those used to print designs on T-shirts—except that the phosphor stripes on Prysm’s screens are just millimeters wide, are made of exotic chemicals that glow red, green, or blue when exposed to laser light, and must be positioned with absolute precision. Which is not too different from clockmaking, when you think about it.
“Our first printing machine wasn’t even in a clean room,” says my host, Patrick Tan, Prysm’s vice president of panel development and manufacturing. “It was in the old Clock Tower Place mill building in Maynard, directly below the offices of Monster.com. Any time they had a party, it would rain wood fibers. We lived with that for as long as we could, but eventually we had to move—and that’s why we’re here in Concord.”
The startup finished that move last August, back when it was still known by its stealth name, Spudnik. It wasn’t until this January—almost five years after its founding by Boston University alums Roger Hajjar and Amit Jain—that the company finally lifted the veil on its technology, which it calls the laser phosphor display, or LPD. As I wrote in one of the first published profiles of the company, Prysm has big plans to use this old-meets-new technology to disrupt the market for large-format displays—that is, the wall-sized displays used for trade shows, stage productions, train station departure-time screens, and Times Square billboards.
Prysm’s current product isn’t huge by the standards of today’s flat-panel displays—it’s a 25-inch-diagonal screen, code-named Maui. But the screen on the Maui has no bezel, which means the units can be lined up edge-to-edge and stacked vertically to form a single, nearly seamless display of any required size. And perhaps the biggest selling point for the new display is that it’s driven by highly efficient lasers—the same commodity blue-violet lasers, in fact, that are found inside Blu-ray players. LPDs therefore use far less electricity than today’s dominant technology for large-format displays, arrays of light-emitting diodes (LEDs).
“Our first targeted application is for large indoor venues like airports, train stations, shopping malls, and convention centers, where LED displays are fairly entrenched today,” says Tan, a veteran of Digital Equipment Corporation (DEC). “One of the big problems with LED installations is that the first order of business is to get Tony the electrician to install power, they’re such big power consumers. For us, we should be able to run off of wall sockets.” A 142-inch screen that Prysm demonstrated recently in Amsterdam (shown in the picture here) used no more power than a microwave oven, Tan says.
The part of the Maui unit that’s being manufactured in Concord, inside a 32,000-square-foot building that formerly housed a maker of components for electron microscopes, is the business end—namely, the phosphor-covered layer of glass where
