PerkinElmer Spotlight 400 Series, User Manual

Page: 82 / 120

82 . Spotlight 400 Series User’s Guide
Adjusting the Height of the Crystal
NOTE: The crystal is mounted on a bayonet assembly similar to that on some light bulbs.
You must always support both ends of the toggle bar when lowering or raising the
crystal.
CAUTION
To prevent serious damage to the crystal, do not move the sample stage
while the ATR crystal is in the lower, working position and touching or
near to the sample.
1. Lower the crystal onto the reference mirror by turning the bar clockwise and slowly
lowering the toggle bar.
2. Using the knurled height-adjustment nut, adjust the height of the crystal so that it just
rests on the mirror under positive pressure (Figure 32).
Figure 32 Adjusting the ATR crystal height
Centering the Crystal
1. Retract the crystal using the toggle bar, by lifting the bar then twisting
counterclockwise.
The crystal is retracted.
2. Place a piece of black PVC electrical tape on a microscope slide, and put the slide on the
microscope stage.
3. Move the stage so that the tape is directly below the crystal, and focus the beam on the
tape.
4. Lower the crystal onto the tape.
The crystal makes an impression in the soft tape.