Relative to the Earth's surface, the sun is at a unique angle every instant of the day, and actually every instant of every 6 months also. Consider this:

Imagine a pair of convex lenses (or a single piece of glass with two convex surfaces. They are designed such that when light from an infinitely distant point (aka the sun), hit this lens, it focuses through a point, and then gets refracted back into a parallel ray at the output lens/surface.

If you put a grid of filters at the focal plane, you would essentially have one pixel of a sun-powered display. The colour of the pixel changes depending on the filter where the sun's rays hit the focal plane. That location depends on the sun's angle, which depends on the time of day... so with good lenses and a super fine grid of different filters, or with a very large lens, you could get maybe, I dunno, 2 or 3 frames per second of display animation from the sun.

I haven't worked out the scale yet, but it would be a super cool lobby window.
-- DanDaMan, Feb 14 2012

Sophisticated Sundial http://www.halfbake...isticated_20Sundial
[mitxela, Feb 14 2012]

Digital Sundial http://www.digitalsundial.com/
Similar concept, different execution [ytk, Feb 14 2012]

Bun. And do it!
-- Psalm_97, Feb 14 2012


(how do these people remember their passwords after 4 years...?)
I like the idea, but I *dunno* about dunno...
gave bunno
-- xandram, Feb 14 2012


I checked my email
-- DanDaMan, Feb 14 2012


I checked my email
-- DanDaMan, Feb 14 2012


I like it.

It's much better than the idea I originally thought I saw:

Sundial Ammunition Window.
-- normzone, Feb 14 2012


I thought it was a faux animated window for interior spaces.
-- FlyingToaster, Feb 14 2012


When you say //2 or 3 frames per second of display animation//, do you mean that a slowly moving patch of light, the colour of which changes 2 or 3 times per second, will be projected on a surface? That's the only way I can see this working, as described. If you had a second, coded grid of filters in the beam of changing-colour light, you could actually get a small set of 2D images that morph into each other.

You don't seem to have factored in the apparent width of the sun. It takes about 126 seconds for an image of the sun to move by its width, so the image/colour will change much more slowly than you hoped.
-- spidermother, Feb 14 2012



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