Competitive Dimensions of Flat-Panel Display
The United States and Japan are once again in high-stakes, high-tech competition, this one over the increasingly important digital device known as the flat-panel display screen. But unlike some of the previous contests, such as the one involving computer chips, the flat-panel display race is not likely to be won by the side that sprints fastest down a straight track.
Indeed, the twists and turns of flat-panel engineering are now making the race look a lot like the one between the tortoise and the hare. For nobody yet knows how to build good flat-panel displays, and thus the early leaders--mainly Japanese companies that have invested billions in liquid crystal display factories--are anything but sure winners. U.S. companies may yet give them a good run with an innovative technique known as field-emission displays.
Flat-panel displays are screens less than an inch thick that can offer image quality comparable to those of their bulky tube-based cousins. They are absolutely necessary for portable computers and are increasingly found on appliances such as cameras and microwave ovens. As the world shifts inexorably toward digital technology, flat-panel displays are becoming the standard interface between man and machine. It was a $10-billion industry last year, and analysts believe it will be double that by 2000.
But the technology still has a long way to go if it is to become ubiquitous. Just take a look at today’s portable-computer screens. They are hard to read unless positioned at just the right angle in just the right lighting conditions. Even then, there are bothersome effects, such as the cursor momentarily disappearing when it moves quickly across the screen. All this, and the screen still costs $500 or more.
Nearly 90% of flat-panel displays sold last year were liquid crystal displays, mostly built by Japanese companies. The appeal of liquid crystal technology is clear: The concept is elegant and deceptively simple. Under normal conditions, liquid crystals appear opaque. But when an electric current is applied to them, the molecules become aligned and allow light to pass through. So by using a wire mesh to control the application of electrical current, then shining a light through the liquid crystal panel, you have a simple flat-panel display.
But this technique has its shortcomings. Probably the most significant is that liquid crystals change from opaque to transparent relatively slowly. This is why the cursor will momentarily disappear when it moves quickly across the screen--the display just can’t keep up with rapidly changing images. That makes traditional LCDs poorly suited for today’s multimedia applications.
The solution the Japanese came up with is the active-matrix LCD. This technology puts a transistor--essentially a tiny switch--behind each pixel, or single dot on the screen, so the electrical current can be carefully regulated and quickly turned on or off. The result is a flat-panel display that almost matches the quality of conventional screens.
But it’s a very, very expensive solution. Not because transistors are expensive, but because they break. A typical color screen uses more than 900,000 transistors, and if one of those is bad, you end up with a visible defect. The result? About a third of active-matrix LCDs made end up in the trash bin outside the manufacturing plant.
Japanese manufacturers will undoubtedly be able to improve their yields as their fabrication equipment improves. But it’s going to take a lot of time and money. And consumers are already clamoring for larger LCD screens, which will be even harder to make.
This is why few companies in the United States are interested in building LCDs--they don’t have the manufacturing expertise, and they don’t want to make the huge capital investments. Instead, they are concentrating on technologies that will be cheaper and easier to build. The most exciting of these is field-emission, currently being pursued by a host of U.S. companies.
Field-emission displays (FEDs) use a thin sheet covered with millions of field emitters--tiny devices that emit electrons. When the field emitters are turned on, they bombard the phosphor dot that makes up a screen pixel, causing it to glow. It’s very similar to the way conventional tube-based screens work, except that conventional screens use a single movable electron gun to excite the phosphors.
The great advantage of FEDs is their redundancy. A display will work just fine even if 20% of the field emitters located behind a pixel are defective. That translates into higher yield rates for manufacturers. And that means lower costs. Even better, FEDs and cathode ray tubes share many of the same parts, allowing manufacturers to leverage old investments.
But most of this is still theoretical. You won’t find any FED screens down at CompUSA right now. Companies in the United States and France are still only manufacturing small, prototype FED screens. But this is about to change.
Silicon Video, the largest flat-panel display venture in the United States, has announced an aggressive effort to bring FEDs to market. The Cupertino, Calif.-based firm, with investments from Hewlett-Packard, Compaq and the Defense Department, has the financial strength necessary. Silicon Video plans to be manufacturing FED screens for Hewlett-Packard notebook computers by the end of 1997.
It may sound quixotic to compete against the LCD juggernaut, but Silicon Video’s Nick Sturiale can tick off a list of reasons why FEDs stand a chance, aside from manufacturing issues. FEDs suck up less power, allowing for longer battery life. They can be viewed from a wider range of angles. And they are even a bit thinner than LCDs.
The next three years will show if Sturiale is right, and if the tortoise really can win against the hare.
