Synchronization by means of multiplier phototubes

ONE METHOD of obtaining accurate synchronization of rotating components with electronic signals is by the use of multiplier phototubes. Accuracies of the order of 1 millimicrosecond have been obtained with this method. The synchronization signal is obtained by scanning a light beam, usually a slit image, across a slit located in front of the phototube. The scanning is done by reflecting the light beam from a mirror which is fastened to the rotating component.