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Expired European patentEurope

Optical absorption spectroscopy for semiconductors

EP 0155744 B1 · Applicant: Philips Electronics N.V.

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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 March 20, 1985 and granted March 7, 1990. A European patent lasts at most 20 years from filing, so its term ended March 20, 2005.
  • 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 September 20, 2010.
  • 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.
FiledMarch 20, 1985
PublishedSeptember 25, 1985
GrantedMarch 7, 1990
Term endedMarch 20, 2005
Application numberEP 85200429
Classification (CPC)G01R31/2656

Timeline

Timeline From EPO dates

1986198819901992199419961998200020022004Application filedMarch 20, 1985PublishedSep 25, 1985Patent grantedMarch 7, 1990Term endedMarch 20, 2005

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