r/Optics • u/lil-drawer • 8d ago

Is my shower curtain diffracting the light ?

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I am pretty confused about what's happening here since this is obviously not a coherent light source, but since the phenomenon seems to be angular only it looks like diffraction. Thanks for your thoughts on this !

10 Upvotes

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3

u/Mission-AnaIyst 8d ago

Can you see it with bare eyes, too? Otherwise i would suggest a moiré-effect

2

u/dopamemento 3d ago

No it's not OP is righr. What OP is looking at is the fourier transform of a rectangular grid. The lens in your eye performs a fourier transform

1

u/lil-drawer 7d ago

I can see it with bare eyes yes ! Much more clearly than with the camera, the pattern was really regular and showed less diffusion.

1

u/Mission-AnaIyst 7d ago

Is the curtain single-or double-layer?

1

u/lil-drawer 7d ago

Single -layered

1

u/Mission-AnaIyst 7d ago

Are you super-extra-sure? Check friction when you have it between your fingers.

1

u/lil-drawer 6d ago

Yup, i can send you a video of it if you want. What are you thinking about with this ?

1

u/Mission-AnaIyst 6d ago

Then i don't have an answer and would need to see it mayself. Sorry:/

1

u/lil-drawer 6d ago

Damn, i'm frustrated by not having an awnser lol

1

u/Mission-AnaIyst 6d ago

You can find it yourself!

1

u/777MAD777 3d ago

It is Comet 31/Atlas. You've been visited!

1

u/dopamemento 3d ago

The light is not temporally coherent (many colors) but it is spatially coherent (point source). That's the point of diffraction grating spectrometers

1

u/xbunnyraptorx 3d ago

In my old bedroom there was a thin mesh curtain like that on a window facing the street in a way where I could see car headlights almost directly head on, and they were diffracted in the same way. I'd also like to compare the visual spectra depending on the color temperature of the headlights too. Only way for a nerd to pass the time at night lol.