About: http://webisa.webdatacommons.org/333918105

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	Here, preferably used is a material whose refractive index difference with respect to the material constituting each of the transparent cover 11, illumination window 2, and viewing window 3 is small, and which has no internal strain.
http://www.w3.org/ns/prov#wasQuotedFrom	google.com