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Instant Tinting Glasses

 Far faster than the conventional UV sensitive lenses now available
  (+5)
(+5) 		  [vote for,
against]

Put two coatings onto each lens: The first coating is an LCD, which darkens when electrified, the second coating is a thin-film photovoltaic cell, which produces electricity when lit by any light.

When the sun powers up the PV layer, it darkens the LCD.

—goldbb, May 27 2009

should have gone to specsavers, Virgil... http://www.youtube....watch?v=eTv1KqYn-oM
[po, May 28 2009]

Translucent Photovoltaic Cells http://solartechtimes.com/?p=364=1
[loonquawl, May 28 2009]

Short blurb on auto-darkening helmets http://www.asashop....n2002/collision.cfm
[loonquawl, May 28 2009]

[link]






       Hmmm. Is the only reason to allow INSTANT darkening?
Polaroid Sunglasses ant that slow are they?
—gnomethang, May 27 2009
   

       I could see this being useful if you can adust the colors.. maybe even be able to add in some custom images.. like something that looks like a pair of eyes so that you can look wide away while you are sleeping.
—Jscotty, May 27 2009
   

       //Polaroid Sunglasses ant that slow are they//   

       Sp. Photochromatic. And yes, it does take about 3 seconds. Polaroid is just a brand, and anyway, it's "polarised" you're referring to, which is simply the filtering out of vertically biased light (including most "glare") in preference to horizontally biased light.   

       What you're looking for is the same technology used for automatic darkening welding helmets. These react quickly enough to prevent eye damage during arc welding (something like 1/1000 of a second reaction time). Typically they use a photovoltaic cell and an LCD layer over the viewing pane.
—Custardguts, May 27 2009
   

       This is what I don't get. If the glass absorbs light, shouldn't it be getting brighter, not darker? Where does all the light go?
—Ling, May 28 2009
   

       into the black hole what is your pupil!
—po, May 28 2009
   

       I second [Custardguts], the proposed technology is baked by auto-darkening welding goggles, although [goldbb] proposes the PV-module to be in the line of sight. This would be possible with translucent PV-cells, which are currently baking [link]. The efficiency of those cells is projected at ~6%, which is better than the cheap amorphous ones they use in the helmets. This means that at least 6% of the light will be filtered at all times, so the glasses would never be totally clear, (the article does not mention which wavelengths are used/filtered, so maybe it has 100% translucency at visible wavelengths. [+]
—loonquawl, May 28 2009
   

       [I_T] - the term photochromatic is rather widely used. Perhaps it's just a proprietary term like polaroid is for polarisation....
—Custardguts, May 28 2009
   

       Thanks for the links, especially about auto-darkening helmets.   

       Inspired by that, I'd like to suggest that one additional feature might be to make the tinting of the lenses adjustable.   

       gnomethang, The problem isn't really that photochromatic lenses are slow to darken... but that they're slow to become transparent afterwards. It just would have been too long a title to say, "Instant clarifying tinting glasses" :)
—goldbb, May 28 2009
   
      
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