Before we dig into this, I’d like to share a little anecdote with you. My family moved into a new house last month, and I was determined to set up my next home theater in style. Previously, my living room had been dominated by a 60” rear projection behemoth. It was time to make the leap to a flat panel.
I called vendors. I studied spec sheets. I visited retail showrooms. In the end, I bought the most expensive, 1366 x 768 50” plasma screen on the market because it was reputed throughout the retail world as being the best display available. Moreover, I’d been to two showrooms and seen this 50” outperform everything else on the walls. Salespeople told me this unit had “deeper pixels” and “superior electronics.”

I hired one of the best-known audio/video installers in my city to mount the plasma and hook it into the rest of my home theater equipment. The back of my plasma features one DVI and one 15-pin VGA connector. The installer rightly connected my high definition cable set-top receiver to the plasma’s DVI port through a 15-foot conduit pipe in the wall. When I explained that I was going to install a media center PC into my home theater that would get used for everything from PVR work to Web browsing to playing HD Windows Media Video movies, he said, “Oh, just pull a VGA cable through and connect that to the VGA port when you’re ready.”

“Will that give me the same quality as a DVI connection?” I asked.

“Absolutely,” he replied with a grin.

In this process, I learned two things. First, I blew a lot of unnecessary cash on my display. It’s not that I didn’t buy the best screen on the market. It’s that there are four or five other screens that are just as good for considerably less money. Why did the one I picked look better than the rest when I viewed them in showrooms? Because the one I bought had a dedicated video feed and correct calibration while the others were fed by splitters and were not set up properly..

Secondly, no, VGA is not an acceptable format for a high-def video stream, especially over 15 foot connection stuffed next to several other data cables. What my system really needed was a $249 2x1 DVI splitter box from a company called Gefen. But this supposedly expert consumer electronics installer either didn’t know any of this or didn’t care to educate me on the options. A PC system builder, with a little education on plasma screen installation, could have provided me with better information and ultimately a superior solution.

In speaking with others both in the consumer and corporate spheres, I’ve found that the large display field is both exploding in popularity and brimming with confusion. Is plasma really an inferior technology about to become obsolete in the face of an LCD onslaught?

Are digital projectors really insufficient for high-def video? Ask five “experts” and you’re likely to get five different answers.

The large display market—and by that we mean something you would mount on a wall rather than sit on a desktop—is rife with opportunity and tall margins for VARs and system builders. But you need to know fact from fiction before you step into the arena.

We’ll cover the basics in this space and help illustrate with several leading product options. There is no reason you need to bow aside and let the pro A/V installers continue to take your large display business.

For LCD Technology Reprise

We need to start here because LCD technology applies to both of the large display categories, projector and flat panel. Liquid crystal display technology dates back to 1888 when Austrian botanist Friedrich Reinitzer heated a cholesterol-like chemical called cholesteryl benzoate and noted that, while heating, the substance turned into a cloudy liquid and then cleared. Upon cooling, the substance turned blue before crystalizing. Eight decades would pass before RCA revisited the liquid crystal phenomenon and found a way to harness it.

What Reinitzer witnessed was the ability for the liquid crystal molecules in a suitable substance to organize in certain ways under certain conditions. How the molecules organize affects how light passes through the substance. The major leap made by RCA was discovering that liquid crystal could be precisely controlled with specific amounts of electricity. What evolved from this was the fundamental design for today’s LCD panels.

In short, a cell of LC material in a display panel is filled with crystals that are oriented, say, vertically. However, when a proper charge is applied to that cell, the orientation of the crystals twist across the depth of the cell. They might be vertical against the left wall but gradually twist 90 (or 270) degrees across the cell’s depth so that they’re horizontally oriented against the right wall. The critical part here is that twisted LC molecules have the ability to alter the vibration orientation of light waves passing through them.

The remaining ingredients are polarizing filters and a backlight. The backlight shines into the first polarizing filter, which only allows light waves with, say, a vertical vibration orientation to pass through. The light then enters the LC cell. If the cell is “off,” the crystals twist the light waves so that they exit the cell in a horizontal orientation. A second polarizing filter, perpendicular to the first, waits beyond the LC cell. Because the light waves have now twisted to a horizontal orientation, they can pass through the second filter. If a charge is applied to the cell, the LC molecules all line up, the light passing through them doesn’t twist, and the second filter blocks the light waves from reaching your eyes, making that cell appear dark.

The step that color displays added was placing red, green, or blue color filters over each cell after the second polarizer, making each cell a sub-pixel. A red, green, and blue sub-pixel cluster together makes a pixel.

An array of electrodes running along each side of the LC layer controls charge addressing to any individual cell. A problem with this array at any point can result in a “dead” pixel, and it’s not hard to see the statistical odds of at least one failure out of four million or so transistors. Dead pixels used to be a large concern with LCD screens, but vendors have made great strides with quality control in recent years, and it’s been a long time since we’ve see a bad LCD pixel, even on a cheap display. Still, you should take care to learn a vendor’s bad pixel return limit (can you return a display with three bad pixels? how about one?) and communicate this to your customers.

Behind the Projector

Projectors based on LCD technology use a series of mirrors and lenses to blast light through a small LCD screen inside the projector and out onto a screen. Actually, only lower-end LCD projectors take this approach. Most units now use three LCD screens, one devoted to each primary color, and combine them into the final projected image in a similar yet reversed approach to what is done with pro-level 3-CCD camcorders. The advantage of a 3-LCD approach is that brightness and contrast can be controlled for each color separately, yielding superior color reproduction.

Despite that a large amount of light is lost from the bulb through the lens because of how LCD filtering works, LCD projectors tend to be the most efficient technology on the market for light output. In essence, you get more ANSI lumens (the unit of measurement for display brightness) per lamp watt with LCD. Additionally, the precise nature of LCD cells makes this the sharpest option for projectors. The rival format, DLP, is sharp, but LCD is sharper, and if your client wants to beam text, spreadsheets, and charts on a wall, LCD will deliver the best results.

Which takes us to DLP, Digital Light Processing, first released by Texas Instruments in 1996. The heart of DLP is the Digital Micromirror Device (DMD), a silicon chip featuring an array of hundreds of thousands or even millions of mirrors, each of which is less than 14 microns square. Each mirror is mounted on a powered lever, sort of like a see-saw. A lamp shines onto the mirrors. If the mirror is tilted toward the light, that pixel is on. If the mirror is tilted away from the light, it is off, and each mirror can switch positions several thousand times per second. The length of each mirror’s on-state per second determines its 1,024-level gray scale shade. Engineers figured out that by bumping each mirror’s angle of movement from 10 degrees to 12 they could enhance the technology’s black levels, one of its original shortcomings.

To add color, a spinning wheel rotates above the mirror array. The wheel’s outer area is comprised of either red, green, or blue filters. If one mirror is supposed to generate a purple pixel, its on-states are timed to only reflect light to the lens when the red and blue filters are passing over it. Some vendors implement a clear segment into the wheel for situations in which brightness is more important than color saturation.

Interestingly, just as some users in the ‘80s and ‘90s were prone to seeing CRT “flicker” caused by low refresh rates, some people could detect a video artifact in early DLP technology called the “rainbow effect.” This artifact was an unfortunate side effect of the color wheel approach. The first generation DLP engines used color wheels spinning at 3,600 RPM. The 2X wheels spun at 7,200 RPM. By the 3X generation, few people were able to still detect rainbows. Apparently, about 9,000 RPM is the cut-off for most susceptible eyes. Still, most vendors are working to implement 4X, 5X, and 6X color wheel designs.

A single DMD DLP projector can generate up to 16.7 million colors—your usual 8-bit-per-channel color system found on decent PC graphics cards. Most cinemas and high-end presentation venues are adopting 3-DMD systems in which the lamp’s white light is split into red, green, and blue paths with a prism, and each color is directed to its own DMD. A three-chip DLP projector can attain up to 35 trillion colors.

“Every projector manufacturer has their value adds,” says Frank Anzures, bid desk manager for BenQ. “For our part, we’ve incorporated a few features to differentiate ourselves from the rest of the market. We’re using the faster color wheel spin rates on our business and home theater projectors to avoid any rainbow effects in the DLP technology. We also use higher-end components in regard to video processing in both the video and computer portions to enhance the display. To the end-user, that means brighter, crisper images, smoother edging, all contributing to a better quality image.”

If you glanced at the numbers from DTC Worldwide, the trend toward DLP is clear. At present, the two technologies are in a dead heat for market share. By 2006, DLP is expected to have opened a nearly 20% lead over LCD

There are a few factors pushing DLP to the fore. For starters, while both formats have improved in quality from their initial designs, DLP has evolved more quickly as is likely to continue to do so as advancing MEMs (micro electromechanical machines) technologies make higher resolution DMD chips more feasible and affordable. Most DLP projectors do not exhibit pixelation when used in home- or office-scale venues, which is one of their advantages over LCD. (LCD projectors up to SVGA resolution, 800 x 600, almost invariably exhibit pixelation.) In general, DLP also maintains a slight edge over LCD in black levels.

Most importantly, though, a 3-LCD design takes up considerably more room than DLP’s color wheel design. This is why practically every sub-four-pound projector on the market is DLP. It’s also worth noting that LG made the innovative step of turning the color wheel into a color drum. As the drum is naturally shorter than a wheel, this enables LG to create DLP projectors less than 2” high.

Epson and the ever-contrary Sony continue to advance and promote LCD projectors, and Epson’s LCD-based PowerLite series now comes close to a four-pound weight. Plenty of other vendors continue to make LCD models—LCD is still half of the market, after all—but you don’t hear much noise about the technology anymore. Pixel sharpness and overall brightness continue to make LCD a strong contender in office environments, particularly for rooms that can’t be dimmed very much, but in circumstances where video is involved, DLP is emerging as the dominant force. This is especially true among the corporate crowd that uses their projector at client sites by day, then takes it home for family use at night.

There is one more technology waiting in the wings that may yet upset both LCD and DLP: Intel’s liquid crystal-on-silicon (LCOS). This approach plants a highly reflective layer of material on top of a silicon substrate, then builds a liquid crystal display on top of the mirror. Essentially, LCOS blends the reflective approach of 1970 LCD calculators with the color filters and addressing of modern TFT LCDs then adds the lamp and optics of a projector or HDTV set. Intel predicts that because it can apply its current mass scale fabrication capabilities to LCOS and that its development should follow the curve of Moore’s Law, LCOS will be able to undercut all competing technologies on both performance and cost shortly. Initial commercial LCOS products are expected in 2005, and unconfirmed reports state that two million pixel LCOS designs have already been demonstrated.

Projector Considerations

As with monitors, two of the top specs everyone looks for in projectors are brightness and contrast. However, after reading our interview below with Joel Silver, you’ll know that these specs are a rough guide at best. Customers are likely to ask you how much brightness they need, and the answer will depend primarily on the distance from the projector to the screen as well as the amount of ambient light in the room. Try this for a rough rule: At 10 feet from the screen, you need 900 or more lumens for a dark room, 1300 or more lumens for a dimmed room, and 1900 or more lumens for a brightly lit room. The farther from the screen you get or the more light you have in the room, the more lumens you need. Fixed projectors in lecture halls often exceed 10,000 lumens.

Tied to brightness is the projector’s lamp. There are three types of lamp bulbs: halogen, metal halide, and Ultra High Performance (UHP), which is Philips’s proprietary spin on metal halide. Halogen lamps tend to shift colors a bit toward yellow, burn for about 70 hours, and cost around $80. Metal halide gives off a much whiter light, lasts for 1,000 to 2,000 hours, but costs around $350. UHP bounces the expected hours up to 4,000 but also jacks the price to roughly $600. Metal halide lamps will still work after 2,000 hours, but they will have passed their “half-life” and start to exhibit dimming.

Given the price of replacement bulbs, it’s important to advise customers on using the proper wattage lamps for their machines as well as running them at the proper brightness levels. This includes running in an “economy” or “silent” mode whenever possible. Using excessive or unnecessary brightness simply shortens lamp life and can often impair image quality.

“What people need to see is what they’re getting for the price,” says Chris Neff, director of marketing for LG. “There are some $1,000 projectors at 1100 or 1200 lumens. That’s kind of dim now that we’re coming out with 1700 at that price point. And we’re going to be focused on the quietness of our units. There’s nothing worse than going into a room to present and hearing that fan. With our RDJ91, you don’t even know it’s on until you see the image on the screen.”

Projector weight goes without saying. As you would expect, less weight means more price. Just like with notebooks, many customers are willing to pay a premium for portability, so be sure you offer them ultralight options. Resolution is in the same boat. More is better...and costlier.

There are plenty of other variables. Probably chief among them is keystone correction. If you beam a projector straight at a screen, the image forms a perfect rectangle, yes? However, if you have to project from off-center, either vertically or horizontally, you get a nasty trapezoid. That’s keystoning. Most projectors offer keystone correction in one plane; relatively few offer it in both.

Is your client forced to run the projector abnormally close to the screen? If so, you need a model with a short throw lens, such as BenQ’s PB8220, which beams a wider image over a shorter distance. How about wireless networking? A full-featured remote? Support for DVI, VGA, component, composite, and/or S-Video? Will it accept simultaneous input from two PCs? If the projector is primarily for corporate use, you want something with a native 4:3 aspect ratio. For home theaters and HDTV content, you want a native 16:9.

Not least of all, familiarize yourself with the range of projector accessories offered by the projector vendor as well as third-party vendors stocked through your distributors. Depending on how much of a total solution you’re offering, you may have to compete in price on the projector, but the accessories—everything from laser pointers to ceiling mounts—will generally fetch excellent margins.