Nikon TIRF Instructions Manual page 15

(4) ND filter
Three ND filters, ND2, 8, and 32, are provided. Each of these filters can be attached to or
removed from the optical path.
(5) Focal point adjustment knob and condenser lens locking screw
You can change the focal point of the laser beam along the path of the objective's optical axis
by moving this knob back and forth.
When the laser beam is focused on the objective's pupil surface, the objective-emitted laser
beam should form parallel rays. Non-parallel rays will pass through the cover glass even when
the optical path of the laser beam is tilted at a critical angle, or greater, relative to the specimen,
degrading image quality or damaging the specimen.
After replacing the objective, follow the steps specified below to adjust the focal point of the
laser beam.
• Turn the laser position adjustment knob to move the laser beam just above the objective.
• Loosen the condenser lens locking screw with a hexagonal screwdriver.
• Move the focal point adjustment knob back and forth while observing the laser beam on the
ceiling of the room or chamber. Try to minimize the spot illuminated by the laser; try to
reduce the width of the illuminated spot by at least half.
• When adjustment is complete, tighten the condenser lens locking screw with a hexagonal
screwdriver.
Indices (circumferential grooves) are provided to indicate various positions of the focal point
adjustment knob that correspond to the objectives used for TIRF observation. Use these indices
to guide laser focal point adjustment.
Never attempt to look into the laser beam. (FDA CDRH: Class II, EN60825-1: Class 2,
IEC60825-1: Class 2)
The objective emits a powerful laser beam. When adjusting the focal point adjustment knob or
condenser lens locking screw, never attempt to look into the objective or the areas near the
objective from above or below the stage as the lens emits a powerful laser beam toward the top
and bottom sides of the stage. To protect your eyes and skin from exposure to laser beam
reflections, never place or mount any reflective materials on the stage, in the room, or on the
chamber ceiling.
I Name and Function of Each Part
3 TIRF attachment
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