[anmorgan]

Are you being specific about the word darken? Because LCDs are design to either allow or block light. So technically an LCD can "darken" incoming light. But I think the point of inconsistent lighting from the environment would be the biggest challenge.

The best example of transparent display I've seen in production is:https://glas.johnsoncontrols.com/

But the material on that seems darker and I believe they use an edge light to provide higher contrast.

I think the distance from the eye, as well, would be difficult if you aren't doing some type of projection, like what is used in the the article.

[numpad0]

Darken as in response to “can’t LCD darken enough” in parent.

Anyways any LCD can be a transparent LCD if you peel off backlight layers if you want to experiment with. Search for “DIY transparent LCD” or “LCD side panel casemod”