The BCAM Camera

The BCAM, or Boston CCD Angle Monitor, is a camera looking at one or more light sources. We describe the application of the The BCAM, or Boston CCD Angle Monitor, is a camera looking at one or more light sources. We describe the application of the BCAM to the ATLAS forward muon detector alignment system. We show that the camera's performance is only weakly dependent upon the brightness, focus and diameter of the source image. Its resolution is dominated by turbulence along the external light path. The camera electronics is radiation-resistant. With a field of view of ± 10 mrad, it tracks the bearing of a light source 16 m away with better than 3 µrad accuracy, well within the ATLAS requirements.