About: http://webisa.webdatacommons.org/187432453

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	Conditional expression (1), as previously described, is a condition which prescribes the relation of the optimal refractive power to the entire system of the second lens unit G2 in a lens system wherein the fully open F number is bright.
http://www.w3.org/ns/prov#wasQuotedFrom	google.com