FOV Mapping

Power ON instrument

Place the FOV mapping grid onto the test aperture (ABB, HBB, zenith)

  • Remove BB or zenith port
  • Attach FOV mapping grid using 4 screws

FOV_Mapping_AERI.xls

  • (ssec/projects/AERI/field guide)
  • rename to FOV_Mapping_SN1NN_YYMMDD
  • make tabs for each port

FOV mapping

  • Set scan speed to 16 cm/s
  • Record spectrum amplitude at 4000 cm-1
    • XLim = 3980-4020
    • YLim:  Use ‘max’ reading at the center gridpoint to set y scale
      • The y grid spacing defaults to 0.25 most of the time, which makes it hard to read values
      • Setting the y scale to have 7 grid boxes forces decimal spacing (0.1), making it easier to read
      • Recommend using YLim = -0.1-0.7, then switch to 0.7-1.4 as needed for higher values
  • Use the pen light tool to illuminate one hole at a time in the mapping grid
  • For each column on the mapping grid
    • Make a background reading
    • Make a ‘max’ reading at the center gridpoint
    • Record the spectrum amplitude at each gridpoint, going down vertically
  • Repeat for each column
  • Repeat for each view port (ABB, HBB, zenith)
  • Return scan speed to 1 cm/s
  • Note: ABB and UW use mapping grids with different hole spacings – be sure to use the correct analysis spreadsheet

Acceptance:

  • The LOS of the FTS shall be aligned with respect to the rotation axis of the scene selection mirror such that the intensity of a white light source is < 1% at the outer extent of the LOS Characterization jig at each optical head entry port (zenith, HBB, ABB)
  • Note: BB aperture is 2.7″

Tuning:

  • SSEC template:  1 gridpoint = 2 deg scene mirror rotation
  • SSEC template:  1 gridpoint = 4 full turns of rear kinematic mount screw