Plane wave interference: a didactic experiment to measure the wavelength of light

A study was conducted to characterize the wavelength of light using plane wave interference. Collimated laser beams were utilized to easily monitor the interference pattern and measure fringe spacing. The plot of fringe spacing was characterized as the angle between the two beams. The plane waves were determined from the same laser beam using a beam splitter while interference images were observed utilizing a charge coupled device linked to a microcomputer.