Hey, I Need My (Color) Space!

January’s Consumer Electronics Show in Las Vegas is always worth a visit, not only because of the many cool (and often ultimately useless) gadgets that are hawked, but to catch up on the latest advances in electronic displays. Everywhere you looked this year, the walls and floors were covered with cool, thin and sexy-looking plasma and LCD monitors while manufacturers also offered up numerous demonstrations of front and rear projection technology.

But as regular readers of my columns and reviews know, "cool," "thin" and "sexy" don’t cut the mustard in many production environments. Yes, these displays can make some very bright images, but so can flashlights. Yes, consumers love the way these displays look in their living rooms, but production professionals working in edit suites often despair at how these displays make their projects look.

The decision by major display manufacturers to walk away from CRT imaging technology (even for high-end broadcast applications) is a scary one. Sure, CRT monitors and projectors are heavy, take up a lot of room and are limited in resolution, but the one area in which they have the upper hand is color accuracy, a battle that the LCD, plasma and microdisplay guys are still fighting unsuccessfully.

There was plenty of evidence at this year’s CES that indicated this is changing. I saw several technology and product demonstrations that may solve the color conundrum as we migrate away from tubes to thin sheets of glass and super-tiny light modulators and shutters.

The first significant demonstration was a pair of 46-inch 1920 x 1080 resolution LCD TVs; one by Sony (Qualia 005, $12,999), and one by Samsung (LNR460D, also $12,999). Samsung makes the LCD glass in both products, and the backlights are strips of red, green and blue light-emitting diodes (LEDs) manufactured by California -based LumiLEDs.

The difference between colors rendered on the LED-equipped TVs and conventional LCD monitors using cold-cathode (fluorescent) backlights was amazing. Samsung’s demo had an HD video feed of a display case of Lava lamps in different colors right next to the 46-inch screen. It was difficult to see any difference in the actual colors versus the display colors.

LumiLEDs claims it can easily attain the NTSC ( SMPTE -C) color gamut and even exceed it by 5 percent with its matrix of 26 red, 26 green and 13 blue LEDs arranged in seven rows (455 LEDs in all). That would also imply that a LumiLEDs -equipped LCD monitor could also be tuned up to accurately reflect the HD color space (REC709).

Way back in the far reaches of the South Hall of the Convention Center, Toshiba and Canon showed their approach to the problem. It’s called the Surface-conduction Electron-emitter Display (SED) and resembles a super-flat CRT display in its design and operation.

The SED uses phosphors, just like a CRT. It employs a low-voltage switching system to turn on and off electron emitters, and a high voltage potential between the emitters and the front glass plate is what attracts the electrons to individual red, green and blue phosphors, again just like a CRT.

Indeed, the demonstration had CRT-like picture quality with rich, saturated colors, great shadow detail, a clean grayscale (as far as I could tell) and no blurring or other motion artifacts. If I didn’t know better, I’d have thought I was watching a conventional CRT.

But the SED is a lot thinner (a few inches), lighter, uses considerably less power and can be manufactured in competitive sizes to LCD and plasma monitors and TVs. The prototype shown measured 36 inches diagonally; Toshiba representatives stated they are likely to come out with a 50-inch production version instead. (No pricing or shipping information was available.)

While the first two demos attempted to tackle the flat-panel color problem, the last was aimed squarely at projection systems. Users of large-venue front projectors have long enjoyed the advantages of xenon projection lamps, which provide a natural color temperature close to that of daylight and can closely match any color space.

But xenon is too expensive and cumbersome for small projectors and rear-projection TV sets. At least, that has been the conventional wisdom for some time. A demonstration by PerkinElmer’s Cermax lamp division at the Mirage showed that it is possible to realize significant improvements in color quality by using small and affordable xenon lamps.

The prototypes shown by Cermax were capable of operation from 350 to 800 watts, and in the 350-watt mode were said to be price and life cycle competitive with 150-watt UHP lamps, commonly used in many front and rear projection engines. UHP technology (and its many copies and offshoots) is typically more efficient in luminous energy than xenon, but the 350-watt Cermax lamp will supposedly level the playing field.

In the Cermax demo, front and rear projection engines clearly had the edge in color accuracy, particularly with flesh tones, shades of yellow and pastel colors. These three are usually the downfall of UHP lamps, which have excessive green-blue spectral energy (that must be filtered down) and are deficient in warm reds and amber yellows.

While some of these products are already shipping, others will need more time rehearsing before their big debut. In any event, it’s gratifying to see that some manufacturers are putting more emphasis on the quality and accuracy of color from the next generation of electronic displays, and not just trying to win style points.

Write Pete at pputman@accessintel.com