About: http://webisa.webdatacommons.org/21966509

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	Photo-electric sending elements are mounted on one of the arms, for example 42 and receiving elements are mounted on the opposite arm, for example 28.
http://www.w3.org/ns/prov#wasQuotedFrom	freepatentsonline.com