Intro to Solid Works

1

• Intro to Solid Works
• Mike Borden
• and
• Off-axis parabola alignment

2

• Opto-mechanics teaches subtlety
• Reduce forces and moments
• Keep structures in balance
• Isolate from vibration
• Will try to demonstrate effect of too much force
• Using PSM
• Using Wyko
• Look at relative ease of use and sensitivity
• More muscles than brains
• Bothers me when wrong screws are used in optical
  table
• Main point of course, use brains not force

3
OAP Alignment

• OAP defines the axis
• Autocollimating mirror and point source brought
  to axis
• Find return beam focus
• Overlap with out going focus
• Will see most astigmatism
• Adjust flat and PSM to align astig with vertical
• Adjust in orthogonal direction to reduce astig

4
First steps

• Look at OAP from its center of curvature with PSM
• Image will be larger than will fit in objective
• Image will look somewhat fish shaped
• A combination of astigmatism and coma
• Tail of fish points toward the optical axis of
  the OAP
• Rotate the OAP in its mount until the astigmatism
  is aligned with the plane of the table
• This makes subsequent alignment easier
• Measure distance from C of C to OAP
• Focus will be about half this distance

5
Autocollimation setup

• Move OAP toward PSM to get to approx. focus
• Point PSM to center light cone on OAP aperture
• Position return flat to capture collimated beam
• Tilt flat to return beam to OAP
• Find return image near PSM objective
• Adjust PSM and flat to get image in objective
• Focus PSM to get smallest image
• It will be largely astigmatic
• First align astigmatism with table top

6
Final steps

• Keep image centered on PSM screen and
• Tilt return flat to see which way makes spot
  smaller
• When badly misaligned it is difficult to tell
  right direction
• Once correct direction is found keep tilting
• Reduce astigmatism as much as possible in on
  direction
• Then work on orthogonal tilt adjustment
• Keep image roughly centered on screen all the
  time
• Spot will reduce to a roughly symmetrical image
• OAP does not have perfect figure
• Spot will never look perfectly round and focused