One of the biggest drains of your cell phone battery (other than making and receiving calls of course) is the illumination of the screen and keypad.

Most screens are pretty much invisible without the backlight, UNLESS you're in direct sunllight or very near a bright artificial light.

Add a light sensor near the earpiece and whenever the phone deems it's in bright enough light to be easily seen, it kills the backlight, thus saving battery power. If you decide you want the light on, this feature is easily bypassed, either from within the phone's menus or by holding the phone with your thumb over the sensor.

This would also be useful for PDAs I guess...
-- kmlabs, Jan 06 2005

Not one single anno?

Oo, you guys know how to hurt a man!
-- kmlabs, Jan 18 2005


How about another light sensor that could tell whether the phone was pressed to your ear, and turn the backlight off?
-- david_scothern, Jan 18 2005


Modern phone screens are quite advanced by now, they have been optimised for backlighting and don't work well without it even in bright light (as you will find out if your backlight goes). It's still a good idea, but you'll probably have to modify the screen design a little.
-- wagster, Jan 18 2005


My phone reacts to light. But unlike the idea, the phone adds a dot screen onto the display in direct sunlight. It makes the entire LCD almost black. I'm not kidding.

It may also turn the backlight off when it does its blackout thing. But how could I tell?
-- Amos Kito, Jan 18 2005


If there aren't any phones with a transflective screen yet, I'm sure there will be soon. My phone is a cheapie and it's useable without the backlight, under very specific conditions.

[Amos Kito], could you elaborate?
-- tiromancer, Jan 18 2005


My Nokia 6682 has a light sensor. Turns the backlight on and off, and even dims it for certain situations. Works like a charm. Baked.
-- joshuahankins, Jul 05 2006



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