User:Mukund.vinayak12/Fresnel biprism

fresnel's biprism is a device used to derive two coherent sources from one. It is a combination of two prism of very small refractory angle placed base to base. Actually it is a single prism in which one angle is of 179 degree and other two are of abot 30 minute each. --Mukund.vinayak12 (talk) 10:45, 8 October 2010 (UTC)