AERI Scene Mirror Cleaning Procedure

Tools and Equipment Required

  • Large phillips screwdriver
  • Ball driver set
  • Squirt bottle of 95% ethyl alcohol
  • Squirt bottle of distilled water
  • Absorbent wipes
  • (Optional) Holding fixture for the scene mirror assembly
  • (Optional) Small dish or bowl to catch water and alcohol run-off


  • The motor cables must never be disconnected with the instrument powered.  Always power off instrument first.
  • Be careful if handling the drum around the scene mirror: it is thin and easily bent.
  • Do not touch the mirror surface except by the stream of cleaning fluid.
  • The mirror assembly must be registered upward upon replacement for proper optical alignment.


  1. Stop data collection and power off the instrument:
    1. Press ctrl-c up to 3 times in the black Cygwin window to terminate ingest.
    2. Switch off the power bar in the AERI back-end.
  2. Remove the front panel from the AERI front-end.
  3. Remove the scene mirror/motor assembly from the front end structure:
    1. The interior fan may obstruct removal of the assembly.  In this case the fan assembly can be slightly rotated by removing the 3 front screws holding it to the hex.  Alternatively the entire fan assembly can be removed.
    2. Disconnect the 4 cables going to the trapezoidal plate:
      1. ENCODER
      2. MOTOR
      3. MO TEMP / PE TEMP
      4. S MIRROR
    3. Unscrew the 4 screws on the trapezoidal plate (see Fig. 1).
    4. Pull the assembly carefully straight out of the support structure (see Fig. 2).
    5. Place the assembly carefully onto a flat surface, or place it onto a holding fixture
  4. Inspect the area inside the hex (from where the mirror assembly was removed); note and clean any debris or obstructions (grass, dirt, nests, etc.).  Inspect the mirror drum for obstructions and circularity.  Note the condition of the mirror surface before cleaning.
  5. Clean the mirror:
    1. (Optional) Place some absorbing material (or a small dish or bowl) below the scene mirror to catch the water and alcohol as it flows off the scene mirror.
    2. Flush the mirror surface with a stream of distilled water followed by a stream of 95% ethyl alcohol. This process should be repeated at least three times (the more times the better: use about 125 cc which is half of a squirt bottle). The flushing should begin with distilled water and end with alcohol. Note: Do not touch the mirror surface except by the stream of fluid.
    3. When done flushing, wipe any excess drops of fluid that may be hanging from the edges of the mirror drum.
  6. Reinstall the mirror/motor assembly:
    1. Carefully insert the assembly straight into the support structure (see Fig. 2).
    2. Register the front plate upward when tightening the four socket head screws.
    3. Reconnect the 4 cables going to the trapezoidal plate.
    4. Return the interior fan assembly to it’s original position, if it was moved.
  7. Reinstall the front panel onto the AERI front-end.
  8. Power on the instrument and resume data collection:
    1. Switch on the power bar in the AERI back-end
    2. Click ingest.bat on the desktop to begin ingest.

Figure 1: Unscrewing the mirror:motor assembly

Figure 1. Unscrewing the mirror/motor assembly

Figure 2: Mirror motor assembly removal or insertion

Figure 2. Mirror motor assembly removal or insertion

Figure 3: Removed mirror:motor assembly on holding fixture

Figure 3. Removed mirror/motor assembly on holding fixture