HIS14 with 0.8mm light capillary: Test results with visible light


Focusing with visible light


Method:
The focussing mirror is illuminated through the VUV-lamp with visible light using a cold-light source. The focused light spot is imaged using a diffusing screen with a scale and a light microscope.


Results:

Horizontal spot profile with 0.8mm capillary

0.8mm capillary
A fit to a Gaussian function yield 182 μm fwhm.

Vertical Spot Profile

0.8mm capillary
A fit to a Gaussian function yield 180 μm fwhm

The expected value is 0.8mm/5 = 160μm.

For comparison:

Spot profile with 1.7mm capillary yields typically a spot gaussian spot profile with FWHM below 300μm (shown here: FWHM = 275μm). Expected value 1.7mm/5 = 340μm

1.7mm capillary