About: http://webisa.webdatacommons.org/97750374

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	A further object is to provide apparatus in the nature of a focimeter for measuring the focal length of an optical element such as a lens and testing it for aberration.
http://www.w3.org/ns/prov#wasQuotedFrom	google.com.au