The Dispersion section of the monochromator for the DMS-90 includes the entrance and exit slits and the grating. Light enters the dispersion section through the entrance slit which is controlled by the slit-adjustment knob on the front of the instrument. This knob adjusts both the entrance and exit slits to provide the resolution desired. Once the light enters the dispersion section, an image of the entrance slit is reflected onto the 1200 line/nm reflection grating, which disperses the incident radiation. This radiation is then reflected off a collimating mirror to give a path lenght of 0.28 meters. The exit slit is set at the same size as the entrance slit and provides the ultimate resolution.
Michael R. Ross
Chemistry Department, College of St. Benedict/St. John's University
St. Joseph, MN 56374
320-363-5482
Comments to author: mross@csbsju.edu
Revised: 1/1/98
URL: http://www.users.csbsju.edu/~mross/ch336/dms90DispSect.html
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