About: http://webisa.webdatacommons.org/420280721

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 other applications, such as optical heads for reading optical discs, two or more detectors are used to detect a reflected laser beam off the optical disc.
http://www.w3.org/ns/prov#wasQuotedFrom	google.com