Difference between temporal and spatial coherence

1. Nov 11, 2013

ppy

Hi,

I am confused about the difference between temporal and spatial coherence. I know coherence is when the waves have the same wavelength.

An explanation in simple terms would be great thanks :)

2. Nov 11, 2013

Staff: Mentor

Last edited: Nov 11, 2013
3. Nov 11, 2013

Staff: Mentor

4. Nov 15, 2013

Claude Bile

Coherence describes the degree of correlation between two phases. Perfect coherence = perfectly correlated, means knowing one phase allows you to deduce the other with infinite precision. Perfect incoherence = perfectly uncorrelated, means knowing one phase gives no information whatsoever about the other phase (i.e. it is statistically random).

Spatial coherence is correlated phase between two points in space.

Temporal coherence is correlated phase between two points in time.

Claude.