Scientists at Penn State have measured the spatial and spectral properties of the ACIS Optical/UV blocking filters.  Here is a list of technical papers regarding the ACIS OBF's:
 

ACIS Flight Filter Transmission Models   The spatial and spectral properties of the ACIS UV/Optical blocking filters are characterized.   Compressed Postscript (196K) | HTML

Transmission Maps of the ACIS UV/Optical Blocking Filters  ACIS UV/Optical Blocking Filters were calibrated at the Synchrotron Radiation Center in June 1995 and April 1996.  The resulting spatial transmission maps provide the finest spatial calibration ever achieved on such filters.    HTML

ACIS UV/Optical Blocking Filter Calibration at the National Synchrotron Light Source  Measurements of the transmission properties of the AXAF CCD Imaging Spectrometer(ACIS) UV/Optical blocking filters were performed at the National Synchrotron Light Source at Brookhaven Laboratories. The X-ray transmissions of two Al:Si/LEXAN/Al:Si three-layer filters were measured between 260 and 3000 eV.      HTML

For more information, see our Chandra links page.