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Exposure meter - obsolete, uncorrected

Soon, after, leaving the slit, the divergent beam encounters the fuse silica beam splitter of the exposure meter. The beam splitter consists, of a thin (1mm) window inclined at 450 which is anti-reflection coated on one surface. Consequently a few percent of the radiation transmitted by the slit is fed to an exposure meter photomultiplier (EMI type 9 This tube has a bialkali photocathode and fused silica window. lent in the same system is also of fused silica which makes the exposure meter UV sensitive. A darkslide is provided in front of t

The abode current from the photomultiplier is integrated by the exposure meter control electronics located in the console Area and the n is displayed as four digits. The control electronics box also houses the EHT supply which should normally be set at 1100V.

manuals store
Tue Aug 5 00:46:52 BST 1997