Transparent surfaces that become opaque

[LightningInAJar]

TL;DR

Surfaces that change transparency.

Are there any materials that go from transparent to opaque when a bright light is shined on it? In particular I would like something that acts like a window until I project a movie onto it and then is opaque in the regions where the light hits it at certain levels of brightness.

 

[TeethWhitener]

https://en.m.wikipedia.org/wiki/Photochromic_lens

 

[Baluncore]

Are there any materials that go from transparent to opaque when a bright light is shined on it? In particular I would like something that acts like a window until I project a movie onto it and then is opaque in the regions where the light hits it at certain levels of brightness.

If sunshine falls on the window, or it is a bright day, the window will become opaque.
No projector can compete with sunlight.
Maybe an LCD window is needed with a separate control.

 

[Jarvis323]

You can also get glass which becomes opaque when you pass a current through it.

https://www.smartglassinternational.com/electric-switchable-glass/

 

[LightningInAJar]

If sunshine falls on the window, or it is a bright day, the window will become opaque.
No projector can compete with sunlight.
Maybe an LCD window is needed with a separate control.

I would not use it in sunlight.

 

[LightningInAJar]

You can also get glass which becomes opaque when you pass a current through it.

View attachment 282247View attachment 282248

https://www.smartglassinternational.com/electric-switchable-glass/

I don't think electrochromic window would help. I like those LED hologram fans, but I want higher res and no moving parts. I want the dark regions to be see thru.

 

[Rive]

You can also get glass which becomes opaque when you pass a current through it.

Erm. Does this means that these will switch transparent in case of a power outage?

Just asking

 

[Baluncore]

Erm. Does this means that these will switch transparent in case of a power outage?

Smart glass does not have “a current pass through it” as that would be very inefficient. Switchable glass has a liquid crystal film, between transparent conductive layers, within the laminate that change optical characteristics when subjected to an electric field.
The glass becomes transparent only when a voltage is applied.
Loss of power does not lead to loss of dignity.