



Session CA - Elementary Particles II.
INVITED session, Friday morning, November 15
Mary Gay D, Holiday Inn
The L3 detector at LEP includes a Silicon Microvertex Detector (SMD). To make use of the accurate position measuring capability of the SMD the position of its elements has to be continuously monitored with an even higher accuracy. An optical system (LDMS) serving this purpose will be introduced. It is based on pulsed laser diodes which through a network of optical fibers, distributors, and micro-optical elements illuminate the silicon wafers. The generated signals are collected using the regular SMD read out, thereby also allowing for the testing of that system. Technical aspects and performance of the LDMS will be discussed.