About: http://webisa.webdatacommons.org/113093733

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	The construction of the known device is in addition difficult to manufacture, in particular when the lenses are aspherical, unlike in the known device, i.e. have a shape other than a spherical shape.
http://www.w3.org/ns/prov#wasQuotedFrom	google.com