Optics > Interference > Thin Films DCS# 6D30.10

NEWTON'S RINGS



APPARATUS
 
Newton's rings apparatus 202-21-D5


DESCRIPTION
The apparatus consists of a long-focal-length convex lens pressed against a flat glass plate.  The reflections off the two inner air-glass interfaces produce a circular interference pattern.  Illuminate with monochromatic light to show that the ring diameters depend on the wavelength of the light.

NOTES
 
Place the Newton's rings apparatus on the document camera on a dark background and illuminate it with diffuse light, either from the overhead lights or the document camera lamp with a diffuser.  Adjust the document camera iris.
We also have pairs of microscope slides that can be passed around the room.