Shortened effect of coherence length of light due to nonselective linear absorption

Abstract

Coherence length is an important feature of a real light wave. From the Michelson interference of He-Ne laser beam, it is found that the coherence length of the beam decreases with the decrease of intensity when the laser beam passes through a nonselective absorption filter and the intensity becomes low enough. This is a novel experimental phenomenon in optics, which verifies the characteristic of discrete wavelet structure of light for the first time.