Luminous Landscape Forum

Equipment & Techniques => Cameras, Lenses and Shooting gear => Topic started by: roskav on November 20, 2007, 07:19:09 am

Title: Young's Slits?
Post by: roskav on November 20, 2007, 07:19:09 am
Hi there ..

I'm trying to work out if I can perform a Young's Slits experiment where I use natural light, but put a filter either over a camera or the slit while I take a photo of the interference pattern created by the slits on a large surface.  Are there any filters which use visible light but narrow the spectrum down to a "single" wavelength?

Hope you can help!

Ros
Title: Young's Slits?
Post by: marcmccalmont on November 21, 2007, 12:58:55 am
Perhaps Edmund Optics
http://www.edmundoptics.com/onlinecatalog/...ryid=41&level=2 (http://www.edmundoptics.com/onlinecatalog/browse.cfm?categoryid=41&level=2)
Hope this helps
Marc
Title: Young's Slits?
Post by: roskav on November 21, 2007, 04:54:51 am
Fantastic thank you.

Ros
Title: Young's Slits?
Post by: drgreenberg on November 21, 2007, 01:34:27 pm
Quote
Hi there ..

I'm trying to work out if I can perform a Young's Slits experiment where I use natural light, but put a filter either over a camera or the slit while I take a photo of the interference pattern created by the slits on a large surface.  Are there any filters which use visible light but narrow the spectrum down to a "single" wavelength?

Hope you can help!

Ros
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You will need to do more than just extract a monochromatic light source from your natural light (which you could do not only with a filter but also by placing a slit in the right spot at the output of a prism or diffraction grating). You'll also need to get a decent amount of phase coherence between the beams hitting each slit. You may need to first pass the light through a narrow pinhole (to get light that is mostly of the same phase across the dimensions of this small aperture), focus the output into a narrow beam and split the beam to direct a beam to each slit (Young used a thin card to do this). Even so, your pattern will not be as defined as if you'd used the output of a laser.

David