COPENHAGEN, July 24 -- GN Store Nord said that its NetTest fiber optic unit's French and American subsidiaries had brought a US patent lawsuit against New Focus Inc. The alleged patent infringement by New Focus relates to tuneable lasers whose patent is assigned to NetTest's Photonetics, SAS and Photonetics Inc. subsidiaries, GN said in a statement. The case is to be heard in the United States District Court for the District of Delaware, where Photonetics Inc. and New Focus are incorporated.