About: http://webisa.webdatacommons.org/270064056

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	In the preferred embodiment of the invention, mirror 11 is a spherically concave mirror having a focal length from 200 to 300 mm, and most preferably having a focal length of 250 millimeters.
http://www.w3.org/ns/prov#wasQuotedFrom	google.com