Question
Sun January 20, 2013 By:
 

what is the difference between point source and extended source?

Expert Reply
Mon January 21, 2013
A point source is really a mathematical construct. It is a point singularity of emission on a source. Point sources emit spherical waves of radiation. The surface of constant phase of light from the point source is called a wavefront. In other words, a wavefront is a surface of constant spatial phase. Extended sources are made up of a collection of such point sources
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