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Is this possible?

  1. Mar 23, 2005 #1
    is this possible??

    I asked around, but no one seemed to know the answer, so I want to ask you physics gurus.

    ok, so I am going to basically modify my cellphone a bit, and I thought of this idea.

    There are a few cell phones these days that have this coating or something, but when the cellphone is turned off, or not active, the screen has a mirror effect. When a button is pushed, and the lights appear,you will be able to see the screen again....like,the light took out the reflection or something.

    now, what causes this effect? Is it some kind of coating? polarizing film? I was thinking if I can buy something to apply to my phone screen to have that effect...

    do you guys have any ideas on how to attempt to do this, if possible...
  2. jcsd
  3. Mar 23, 2005 #2


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    I'm certainly no expert at any of this stuff, but I can only think of two approaches to that (some variations of them, though). I would suspect that there's a second layer of liquid crystals in there. One behind the display could act as a shutter to hide a real mirror at the back. Conversely, one in front of the display could become a mirror when activated. I have no idea whether or not that's what's actually being done, but it's all I can think of right now.
    I'll be very interested in finding out the real answer myself. Hope somebody out there knows. :smile:
  4. Mar 25, 2005 #3
    It's most like a transreflective screen. When it is off you can see a rather clear reflection of yourself, but when it is turned on, since there is some light going from it, your reflection is not so clear anymore. The good thing about these screens is that in sunlight you will still be able to see the screen well because it reflects the sunlight, making the screen brighter.
  5. Mar 25, 2005 #4


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    Okay... I hadn't considered that the screen was illuminated. I was thinking of a regular LC display. (My cell is fairly old; it only lights up if you order it to.) :redface:
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