About: http://webisa.webdatacommons.org/227739341

Property	Value
http://www.w3.org/1999/02/22-rdf-syntax-ns#type	http://www.w3.org/ns/prov#Entity
http://www.w3.org/ns/prov#value	If the refractive index of the laminae is, n; the index of refraction of the medium, for example air, is n', (n' = 1, in the case of air) and d is the geometrical thickness, the phase retardation ?? is given by ##EQU4##
http://www.w3.org/ns/prov#wasQuotedFrom	google.com