Luminescent Screen Monitors

General description :

The ESRF Injector system contains a total of 23 Luminescent Screen Monitors (also called Fluorescent Screen Monitors) : 4 in the TL-1 Transferline (at 170MeV), 8 in the Booster-SY and 11 in the TL-2 Transferline (at 6GeV).

The currently used screen material is commercially available Chromium doped Alumina that can be pneumatically inserted in the beam path.

The light emitted from the screen at the point of beam interception is collected by a simple optical system and focused to an analog CCD camera. These cameras are all connected via 75ohm cables to a video network that directs a selected video source to both an analog video monitor and a framegrabber in the Control Room for visualisation and data acquisition.

A total of 6 of these systems were upgraded in the year 2001 to allow for a better optical quality and a precise adjustment of light intensity levels. The resolution is estimated at better than 200um fwhm.

References & links of relevant papers and presentations :

B.K.Scheidt, “Upgrade of the ESRF Fluorescent Screem Monitors”, DIPAC’03, Mainz, 5-7May 2003.
http://accelconf.web.cern.ch/AccelConf/d03/papers/PM14.pdf