People are silhouetted against a display of the Nikon brand logo at the CP+ camera and photo trade fair in Yokohama, Japan, February 25, 2016. REUTERS/Thomas Peter

WASHINGTON (Reuters) - The U.S. International Trade Commission said on Friday it has launched a patent infringement investigation of certain Nikon digital cameras, software and components based upon a complaint launched by Carl Zeiss AG and ASML Netherlands B.V.