Negative Group-delay-dispersion mirror (NGDD-mirror) multilayer structures include a generally-orderly arrangement of layers or groups of layers in which the function of certain individual layers or groups of layers can be recognized and defined. The structures are broadly definable as a rear group of...http://www.google.de/patents/US6154318?utm_source=gb-gplus-sharePatent US6154318 - Group-delay-dispersive multilayer-mirror structures and method for designing same
