Transflective screen = better battery life?

[QYV]

My understanding is that the transflective screens on newer PPCs like the Axim are truly backlit, rather than the sidelighting prevalent in older devices. I also thought I read somewhere that this meant a small improvement in battery life (the 3900 is supposed to have much better battery life than previous iPAQs, for example). Am I just delusional?

[Janak Parekh]

Both are correct. :) Backlighting takes less energy than sidelighting. A lot of the sidelights spill outside of the viewing area.

--janak

[Chris Hendriks]

the potential power savings comes as a result of the method of lighting the screen. One method is to use a flourescent tube as a light source - this method uses more power, takes up more space due to additional supporting circuitry (power inverter), and can result in some electro-magnetic interference.

The other method is to use white LEDs as a light source. These often are brighter, last longer and are more energy efficient.

In addition, a screen designer has somewhat more control over the screen color by selecting different LEDs. For example, a normal lightbulb that you purchase from a store (depending on the brand) casts different variations of "white" light. Some are more pinkish, some greenish, some bluish, etc. The same holds true for the light from LEDs.

[Saaby]

I'm not really a PocketPC expert (yet) but I AM a LED expert...so pull up a chair.


The flouressent lighting in some PDAs is not flouressent, but a close relative--cold cathode flouressent. Practically the same, but CCF is just a little different--mainly it's smaller. On a large scale, say, lighting your house, flouressent lights are more efficient--but on a smaller scale, say, a PDA--LEDs are more efficient, smaller, and more durable.

LEDs, however, are only capable of producing light in a narrow spectrum. Because of this white LEDs are not actually white LEDs, but blue LEDs with a phosphor applied to the die that is able to put out more light. As a general rule, white LEDs have a tint somewhere between green/blue to purple--depending on how much phosphor is applied. Also, they are usually lacking in the red spectrum.

Shameless plug time--how do I know all this? A little place I call www.candlepowerforums.com

Ok....I'll crawl back under my rock now :P

PS--Hey, sorry--this is going to be WAY off topic, but I'm new to phpBB (But not Forums)--is there a spell check around here?

[Pony99CA]

The flouressent lighting in some PDAs is not flouressent, but a close relative--cold cathode flouressent.

...

PS--Hey, sorry--this is going to be WAY off topic, but I'm new to phpBB (But not Forums)--is there a spell check around here?
There's no automated spellchecker that I know of. But, in some chat rooms, people call me the spellchecker, so let me help. It's fluorescent. :-D

Don't worry, it's not the worst spelling mistake I've seen. One guy on AOL said he was in "quality controll" (sic). :lol: I checked his profile a while later, and noticed he had a different job. I wonder why.... :twisted:

Steve

[Dave Beauvais]

I'm not really a PocketPC expert (yet) but I AM a LED expert...so pull up a chair. ... Shameless plug time--how do I know all this? A little place I call www.candlepowerforums.com ...
Thanks for your reply as well as the link to those forums. Maybe someone there can tell me where to find CR1616 batteries for my keychain LED flashlight that don't cost more than the freakin' keychain! ;)

--Dave

[Saaby]

Maybe someone there can tell me where to find CR1616 batteries for my keychain LED flashlight that don't cost more than the freakin' keychain! ;)

--Dave


I personally reccomend eBay, you can probably get like 100 for $10 or something. Ask though, it's an amazing little community...