The component that really eats battery life in UMPCs is the Cold Cathode Fluorescent (CCFL) backlight, which illuminates the LCD screen.
Current UMPCs use 7-inch screens. Previously, the largest market for these has been car navigational PCs and similar applications, a helpful source at a UMPC manufacturer explains.
CCFLs are a perfect choice for cars, because vehicles have plenty of electrical power available. In addition, 7-inch screens are among the cheapest in terms of dollar per inch, because the dimensions mean they can be cut from the larger sheets of LCD material that manufacturers produce without any wasted screen at the edges.
As a result there's a huge supply of low-cost 7-inch LCDs available to feed demand from the auto market. But they use those power-hungry CCFLs.
These, battery-eaters unfortunately, are the same screens that manufacturers have been putting into their UMPCs (which, of course are forced to use relatively puny batteries to keep their weight down).
However, change is on its way, the old power-hungry CCFL screens are living on borrowed time. Small screens, like those in mobile phones and cameras already use LEDs for illumination, and as LED prices come down this trend is spreading rapidly up to medium and large LCDs.
LED backlights use as little as half the power of CCFL backlights. This will translate into an extra 30 minutes of battery life for the next generation of UMPCs. That next generation will be rolling out around the end of this year, assuming the first generation of products haven't totally killed the market for UMPCs.
You may not think any extra 30 minutes sounds like much, but it is a 25 percent improvement. Of course, knowing that new features sell products, manufacturers might be tempted to use some of that extra battery life up with more power-hungry features like larger screens. Plus ça change µ
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