h a l f b a k e r yThis ain't rocket surgery.
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Vantabubble
Vanta black with negative detail, done with a bubble wrap like structure | |
If bubble wrap could be made solid then an open window could be cut in the top of each bubble . If the top and bottom layer was painted with Vanta black then light would have the added loss of bouncing around in side the bubble.
Size of black bubble pixel relative to window size would matter. Internal
walls between vanta's could be clear to allow incoming light to hit lower Vanta black.
It could even be a multiple level photon parking construction.
Perfect black
https://youtu.be/JoLEIiza9Bc
Exactly this experiment, done. [RayfordSteele, Dec 15 2018]
toffee recipe
https://bearingdrif...ee-for-christmas-2/
[Voice, Dec 17 2018]
Nature there first
https://www.physics...dden-structure.html
Not quite a bubble but 3D. [wjt, Mar 26 2020]
[link]
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// photon parking construction // |
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Eh ? What you've designed is a fractal-like black-body absorber with an increased surface area. |
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Car park: cars go in, stay a while, cars go out. |
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Absorber: photons go in, absorber gets hotter. Nothing comes out until the absorber equilibrates with incident radiation. |
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Would fractalizing a Vantablack surface actually make it
darker? Instinctively, I'd say not - the surface is already
"rough" at what is presumably the optimal length scale for
absorbing light. My guess is that for every photon that is
trapped because of the large-scale geometry of the surface
(ie, in your bubble-wrap), another photon that would have
been trapped will instead be reflected, with the net result of
no effect. |
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Making the layer thicker though, must give more space for photon trapping geometry. Wouldn't the .035% photons, missing the Vanta black, be hitting the backing material? Trying to minimise this backing material by an open gap to another Vanta black layer would catch another fraction of these photons. Ooh, possibly aerogel Vanta black. |
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Having another layer could then shield whatever mechanism you want to dump this incoming energy. Having a greater capacity , at the cost of dimensional space, means there is a time differential of parking cars versus time to crush them and truck them away. |
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Thought experiment: leaving aside the vanta part, would black
honeycomb be darker than black slab toffee? |
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Of course it would, because black slab toffee is hollow, goes on forever, and it's full of stars. |
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Check the link. Watch all the way to the end. |
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Waiting for vantachocolate to show up... |
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Less fattening than toffee, certainly. |
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More nature, showing us up. see link. |
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I guess I don't understand what the goal is here. An
even blacker surface, achieved by adding small
holes leading into a black interior? |
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Vantablack is a thin layer of nanotubes, The idea was for a larger 3D structure with voids in the Vantablack, to be 'blacker'. Not unlike this newly discovered insect wing. |
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