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Show diffraction patterns. Classes Used: PHYS 101, SCIENCE ONE, PHYS 158
To show interference and diffraction effects using a laser as the coherent source.
Laser, gratings and slits
A laser can be used directly behind prepared plates on which are a series of slits. Check that the laser does not have a diffusing lens attached to the front of the laser.
The slits film included four sets of double slits with different separation between slits (but the same slit thickness). There are also four sets of demo with the number of slits range from 1 to 4.
A circular disk with single slit that has an adjustable width is specifically provided for single slits interference demonstration.
Also available is a 2000 lines per inch diffraction grating which produces a spectrum of spots 1 metre apart on the walls of the theatre, a fine-meshed sieve, an adjustable thickness single slit and two fine holes.
Another possibility exists with the red/green laser and a diffraction grating. Simply turn on both laser colours at the same time through a diffraction grating to show the distance diffracted is wavelength dependent.
Demo room information