The core idea is for a display (watch, PDA, phone, laptop, etc) that stays off unless someone is looking at it. When the person looks away, the display turns off again.

The easiest way to do this would probably be to shine an IR light off the display and look for its reflection (implying the light is reflecting off an eye). This is obviously frought with slop as any reflecting surface in range would turn the display on, as would passive IR sources in the area. This can be refined by using an encoded signal - even just a series of on/off cycles per second - and looking only for that signal.

This can be refined even further by using a camera and facial recognition. If the camera can determine a face is pointed at it and is likely in range to see the display, the display turns on.

The ultimate refinement would be to recognize the user specifically and only turn on the display for that user. This exists, in part, in the form of biometric security software/hardware though I'm not familiar with any implentation for a device smaller than a laptop.

There's probably no benefit to this idea, other than some small engery savings (though any savings might be offset by the recognition equipment).
-- phoenix, Feb 27 2008

I'd turn this the other way round - a display that turns on when you look at it. That would be useful for, say, ads, or information booths, or other public area purposes, along the lines of escalators that turn on when someone enters them. And then, like the escalators, it could simply stay on long enough to fulfill its function, then shut off again.
-- DrCurry, Feb 27 2008


//There's probably no benefit to this idea, other than some small engery savings (though any savings might be offset by the recognition equipment).//

Hey! I was going to say that. A watch LCD is incredibly low power. Some are lower power than the LED you would use to check for eyes.

Inrush current on an LCD is also rather high, so if the watch was rapidly detecting and not detecting a face (lets say you're in the bathroom, around several mirrors if you have), you'll be spending more turning on and off.

Security is a possible useful feature tho. Secure LCDs are done differently, however, and in more reliable ways.
-- ericscottf, Feb 27 2008


//on when you look at it// surely thats exactly what phoe said.
-- po, Feb 27 2008


They have software that links with the bluetooth of your phone, so if you, and you phone leaves, your computer locks. Another similar idea is eyeball sensors on outdoor ads that count how many people looked at them. I like the facial recognition camera on a monitor idea. That provides a security feature, but the finger print scanners are still the easiest.
-- MisterQED, Feb 27 2008


I can't find a link to it, but I saw a documentary a couple of years ago where an office partition would turn from frosted to clear when the people on either side looked at it (so they could see each other to discuss something). Can't remember the details (probably facial recongition and stuff), but it shows that this idea could be done.
-- neutrinos_shadow, Feb 28 2008


Spelling the L gives the idea kind of a Spanish flavor.
-- bnip, Mar 02 2008


How do you know your computer doesn't already have this feature?
-- MaxwellBuchanan, Mar 02 2008


Can we have one that turns off when looked at?
-- RayfordSteele, Mar 02 2008



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