LIGHT BEAM CONTROLS


The height of the beam is controlled by the 
knob near the top of the illumination tower.  
The height of the beam is shown in the small window above the height control knob. The 
lever between the height control and window 
is used to put neutral density filters, cobalt 
and green filters in the light beam.

The top portion of the light tower rotates the 
light beam.  The post that the height 
adjustment knob is on can be grasped to 
rotate this part of the tower.  The amount of rotation is noted on the scale at the position 
of the metal rod below beam height control.  
This is useful, for example, in measuring the rotation of toric contact lenses.