Expired European patentEurope
Process for the measurement of the thickness and refractive index of a thin film on a substrate, and a device for carrying out the process
EP 0531354 B1 · Applicant: FRAUNHOFER-GESELLSCHAFT ZUR FÖRDERUNG DER ANGEWANDTEN FORSCHUNG E.V.
Overview
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Listed from its EPO record in Patent Yard's archive of European patents past their term. Its claims, description and drawings are in the EPO PDF and on Google Patents, and the Claude kit works from them.
Why it's free to use
- Filed May 29, 1991 and granted August 23, 1995. A European patent lasts at most 20 years from filing, so its term ended May 29, 2011.
- A supplementary protection certificate, which can extend a medicine or crop-protection patent, adds at most five and a half years, so even that would have ended by November 29, 2016.
- We check European rights only. A US or other national patent in its family could still be in force: check its family on Espacenet or Google Patents.
FiledMay 29, 1991
PublishedMarch 17, 1993
GrantedAugust 23, 1995
Term endedMay 29, 2011
Application numberEP 91909692
Classification (CPC)G01B11/0675
Timeline
Timeline From EPO dates
Sources & verification
Official EPO records
Everything on this page comes from the EPO record linked above. EPO data used under CC BY 4.0.