How can we measure the wavelength of light?

1 Answer
May 8, 2018

I would use Young's Double Slit Experiment (1801).

Explanation:

This is one of the classical experiments in Optics and I think it was used by Young to evaluate the wavelength #lambda# of Sun light.
Here it is a diagram of the set up:
HyperPhysics Concepts

on the screen you will detect a series of bright and dark frinjes whose positions, #y#, can help you to evaluate the wavelength (#m# is the order, zero for the central maximum and #1, 2, 3,...# for the other maxima above or below the central maximum).