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by jaekwon 5658 days ago
see jws's post above.

  *SUN*

++--++--++--++--++ layer 1

--++--++--++--++-- layer 2

layer 1 polarizes all light in the '+' direction or the '-' direction. layer 2 does the same, but is the inverse of layer 1.

Notice that ambient light can pass through at an angle because the light didn't pass through both polarization directions. I think jws is saying 25% of ambient light passes through because the polarization step takes 50%, but half the ambient directions are blocked off completely (say by the moire patterns) so that makes 25% of ambient light.

1 comments

That still won't work the way I think you intend. This will block light that enters perpendicularly, while passing some of the light that enters at an angle. The problem is that light entering at an angle is not aimed at your pupils. Allowing ambient light to pass at an angle only lights up your eye socket, while blocking everything (sun and ambient) that was bound to fall anywhere you could detect it.
"an angle" refers to any angle other than the angle directly from the sun.

when you look outside the window, any sunlight that enters your eyes from the angle of the sun is the sun because the sun is so far away. this is why we have well defined shadows.

any light that comes at an angle is all the light that did not come directly from the sun. light coming at an angle is directly aimed at your pupils if you're looking at the source.

what you said, the only way it's true, is if you're always looking directly at the sun.

>"an angle" refers to any angle other than the angle directly from the sun.

So do these conceptual glasses have a way to find the direction of the sun, and adjust the moire patterns in real time? Based on the description, it sounded like it would always block rays normal to the plane of the lens, while allowing rays to pass through at any other angle. Rays from the sun will only rarely be normal to the lens, and so they will only rarely be blocked, without an active adjustment to change the "rejection angle." Short of that, I don't follow how the glasses can "tell" sunlight from ambient light, and I don't think it can be done without active logic.

I wasn't talking about the glasses but rather a new window system for homes. But yeah, the windows in my idea would require adjustment based on the time.