Patent Yard Sign in
Expired European patentEurope

Optical switch

EP 0579166 B1 · Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION

EPO PDF

Overview

The published document from the EPO: abstract, claims, description and drawings. Open it full size

Read the whole patent

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.

Google PatentsEPO PDF

Why it's free to use

  • Filed July 13, 1993 and granted June 18, 1997. A European patent lasts at most 20 years from filing, so its term ended July 13, 2013.
  • 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 January 13, 2019.
  • 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.
FiledJuly 13, 1993
PublishedJanuary 19, 1994
GrantedJune 18, 1997
Term endedJuly 13, 2013
Application numberEP 93111190
Classification (CPC)G02F1/3521

Timeline

Timeline From EPO dates

1994199619982000200220042006200820102012Application filedJuly 13, 1993PublishedJan 19, 1994Patent grantedJune 18, 1997Term endedJuly 13, 2013

Sources & verification

Official EPO records

Full published documentClaims, description and drawings as a PDF.EPOEuropean Patent RegisterProcedure, status, file inspection and legal events.EPOLinked open EP data recordThe bibliographic record this page is built from.EPO

Cross-check elsewhere

Google PatentsFull text, worldwide family, citing patents and legal events.patents.google.comEspacenetNational family members and their legal status.European Patent Office

Everything on this page comes from the EPO record linked above. EPO data used under CC BY 4.0.