Optical switch arrangement with synchronisation feature and in particular optical protection switching module and optical hitless protection switching module using such an arrangement and methods realized by such arrangement and modules

Granted: Nov 2, 1999 Filed: Feb 14, 1997

This patent predates the USPTO's electronic file wrapper — prosecution documents from this era exist only in the Patent Office's paper records. A certified copy of the file history can be ordered from the USPTO's paper archives.