# electrically tinting glass? **URL:** \ **Category:** Factual Questions\ **Created:** [February 23, 2013, 3:14am UTC](https://boards.straightdope.com/t/electrically-tinting-glass/651143 "2013-02-23T03:14:35Z")\ **Posts on this page:** 9\ **Page:** 1
**Author:** ![Uber\_the\_Goober](https://avatars.discourse-cdn.com/v4/letter/u/58956e/32.png) [@Uber\_the\_Goober](https://boards.straightdope.com/u/Uber_the_Goober)\ **Post date:** [February 23, 2013, 3:14am UTC](https://boards.straightdope.com/t/electrically-tinting-glass/651143/1 "2013-02-23T03:14:35Z")
I don’t know how to Google what I’m looking for. Maybe I can explain it, and your combined brainpower can help me refine my search terms? A pane of glass that, when electrically energized somehow, changes colors / and or tints to some degree. I think there was a scene in Iron Man where Tony Stark is waking up in his bedroom and his windows “untint” and he can see the ocean view. Is that a movie-style extension of a technology that exists? Or was it totally made up? [This](http://en.wikipedia.org/wiki/Smart_glass) seems to only make the glass turn a milky white color. I’m wondering about other colors, or a sunglasses style of tint, which this wiki article doesn’t describe. I also wonder if anyone here understands this technology well enough to be able to tell me if you always change the opacity of the entire pane of glass, or if certain portions of it could be changed? Like a shape or something? I have a ridiculously futuristic idea which hinges on the possibility of this technology existing and being manipulable to a degree that I can’t find evidence for … yet 🙂 ---
**Author:** ![Crafter\_Man](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/crafter_man/32/458_2.png) [@Crafter\_Man](https://boards.straightdope.com/u/Crafter_Man)\ **Post date:** [February 23, 2013, 3:41am UTC](https://boards.straightdope.com/t/electrically-tinting-glass/651143/2 "2013-02-23T03:41:07Z")
Been around for decades. [Here ya go](http://www.flightgear.dk/flash.htm). ---
**Author:** ![beowulff](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/beowulff/32/542_2.png) [@beowulff](https://boards.straightdope.com/u/beowulff)\ **Post date:** [February 23, 2013, 3:45am UTC](https://boards.straightdope.com/t/electrically-tinting-glass/651143/3 "2013-02-23T03:45:26Z")
[Electrochromic glass.](http://www.saint-gobain.com/en/group/innovation-and-research/new-products/sgs-lightuning) ---
**Author:** ![Uber\_the\_Goober](https://avatars.discourse-cdn.com/v4/letter/u/58956e/32.png) [@Uber\_the\_Goober](https://boards.straightdope.com/u/Uber_the_Goober)\ **Post date:** [February 23, 2013, 3:53am UTC](https://boards.straightdope.com/t/electrically-tinting-glass/651143/4 "2013-02-23T03:53:05Z")
I tell ya man…know what’s really pathetic? I’ve welded before with the auto-darkening lenses and never put two and two together that hey, that’s electrochromic! And it’s exactly what I’m thinking of! Do’oh! Thanks for that. ---
**Author:** ![Hail\_Ants](https://avatars.discourse-cdn.com/v4/letter/h/dc4da7/32.png) [@Hail\_Ants](https://boards.straightdope.com/u/Hail_Ants)\ **Post date:** [February 23, 2013, 4:00am UTC](https://boards.straightdope.com/t/electrically-tinting-glass/651143/5 "2013-02-23T04:00:37Z")
The new [Boeing 787](http://www.youtube.com/watch?v=cf3WJM72sYs) has these for the passenger windows (no more physical, slide-down window shade!) They’re considering retrofitting them to the 777… ---
**Author:** ![WarmNPrickly](https://avatars.discourse-cdn.com/v4/letter/w/d78d45/32.png) [@WarmNPrickly](https://boards.straightdope.com/u/WarmNPrickly)\ **Post date:** [February 23, 2013, 4:32am UTC](https://boards.straightdope.com/t/electrically-tinting-glass/651143/6 "2013-02-23T04:32:46Z")
> [@Hail\_Ants](#): > > The new [Boeing 787](http://www.youtube.com/watch?v=cf3WJM72sYs) has these for the passenger windows (no more physical, slide-down window shade!) They’re considering retrofitting them to the 777… What advantage does this hold over the shades? I would think this has some serious failure modes. The only failure of the shade is if it gets stuck. ---
**Author:** ![Glazer](https://avatars.discourse-cdn.com/v4/letter/g/a88e57/32.png) [@Glazer](https://boards.straightdope.com/u/Glazer)\ **Post date:** [February 23, 2013, 5:10am UTC](https://boards.straightdope.com/t/electrically-tinting-glass/651143/7 "2013-02-23T05:10:46Z")
It is made with laminated glass. That is two panes bonded together with a plastic inner layer. The plastic inner layer has charged particles in it that when exposed to a magnetic field line up allowing light to pass through. Take away the field and the particles scatter in different orientations blocking the light. Depending on how the magnetic field is manipulated you can do fades or wipes allowing different effects. Gradual tinting or just tinting part of a pane for example. You can get this in different colors although I don’t think they have it so as to change colors, yet. Failure mode is the glass goes dark so you wouldn’t want to use it for windshields. It is rather expensive and hard to install. I have installed this glass in conference rooms before. ---
**Author:** ![Hail\_Ants](https://avatars.discourse-cdn.com/v4/letter/h/dc4da7/32.png) [@Hail\_Ants](https://boards.straightdope.com/u/Hail_Ants)\ **Post date:** [February 24, 2013, 4:40am UTC](https://boards.straightdope.com/t/electrically-tinting-glass/651143/8 "2013-02-24T04:40:53Z")
> [@WarmNPrickly](#): > > What advantage does this hold over the shades? I would think this has some serious failure modes. The only failure of the shade is if it gets stuck. Well given what **Glazer** (which for those who don’t know is what you call a glass worker) says above about it failing to dark, I can only guess that there are numerous systems to prevent this as, in a plane, you’d want it to fail safe to clear. Other than that, the advantages are that the Capt can manually override each window’s setting to clear for takeoffs & landings. Plus it probably saves weight. Also gives the passengers a range of dimnesses rather than just all or nothing. And it’s high tech & neato looking! ---
**Author:** ![Glazer](https://avatars.discourse-cdn.com/v4/letter/g/a88e57/32.png) [@Glazer](https://boards.straightdope.com/u/Glazer)\ **Post date:** [February 24, 2013, 4:51am UTC](https://boards.straightdope.com/t/electrically-tinting-glass/651143/9 "2013-02-24T04:51:04Z")
Or if an engine catches fire the captain can darken all the windows so the passengers don’t panic. :science