Accurate remote distance measurement using a CCD camera

A method for determining the position of a target in space is described. The system uses a CCD camera observing light sources either through a lens or a simple aperture. Results from simulations and experiments are presented, showing that the position of a single image can be found to within about 0.5% of the pixel size. This measurement system was studied for the alignment of the inner tracker in the CMS experiment at CERN and its high accuracy and reliability make it an attractive candidate.