A High-Resolution Phosphor Screen Beam Profile Monitor

A high-resolution luminescent screen beam profile monitor was developed to allow viewing of both conventional large diameter SLAC e+/e- beams, and also collider rf-bunches having small transverse spatial extent, with one instrument. The principal features of the monitor are described. They include the two-power magnification system offering magnifications of 12 and 78X, respectively; the reticle grid which is optically superimposed on the screen image by a cube beam splitter; selection of a suitable camera; and the Al2O3(Cr) phosphor screen. A simplified version of the monitor for viewing of only micronsized beams for applications in the collider arcs and final focus regions and achieving a magnification of ~40X, coupled with a resolution of ~20¿m is also presented.