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The diffraction pattern of light reflected from a cylinder is different to that from light going past an edge.You might want to paint the wires black.
I haven't tried some new technology like Vantablack, though. But considering how it works, I don't think it would make much difference. Remember that a borosilicate glass submerged in sunflower oil still produce diffraction pattern, even though they have very similar refractive index which makes it almost invisible.
Quote from: hamdani yusuf on 22/07/2023 22:48:37I haven't tried some new technology like Vantablack, though. But considering how it works, I don't think it would make much difference. Remember that a borosilicate glass submerged in sunflower oil still produce diffraction pattern, even though they have very similar refractive index which makes it almost invisible.I forgot about the peculiar result in diffraction pattern produced by a single edge made of galvanized steel. It seems like we get interference of light from the core metal and from the coating layer. So I can't predict one way or another until I do the experiment in real life using Vanta black or its equivalent. I'm curious why there's no mention to musou black in Wikipedia while there are some videos about it in YouTube.
Fraunhofer did something similar with wires.I had a go at copying it- after all, I have access to machine-cut screws of pretty good accuracy- and I can check the pitch easily enough.So I made a grating with a 0.4mm pitch screw and some about 0.2mm coper wire.Took a while, and it's fiddly as hell.And it was lousy.The diffraction pattern was all wrong.Until I painted it black.In retrospect I might have done better with black sewing thread.
Someone else also tried to demonstrate diffraction and interference effect of two edges on the same side.
This video shows the setup of the 2 Edge Diffraction pattern experiment. The diffraction pattern has more than 100 nodes in the pattern. It uses 2 razor blades held in binder clips and a laser pointer. The razor blades and laser pointer are about 20 feet from the paper displaying the diffraction pattern.
I've made the double wires experiment using needles of different sizes. The first experiment used 0.2 and 0.3 mm needles, while the second experiment used 0.3 and 0.6 mm. The diffraction-interference pattern are less regularly spaced. The brightness of the fringes are also less periodical.It supports the hypothesis that the interfering light sources come from the edges instead of the space between them.
Its shape implies that the slits are much narrower than the distance between them.
Video showing single slit diffraction of a laser as the slit width is adjusted. Suitable for A-Level Physics.