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  1. Set laser to central wavelength, 970 nm
  2. Manually adjust pockels to about so beam is just bright enough on card to see
  3. Check beam is still passing through irises of PPC in bypass mode
  4. Adjust angle of prism such that beam passes through center of exit iris
  5. Direct beam into bottom of table periscope, through an iris on the table and the iris on the bottom of the periscope
  6. Adjust the angle of the mirror at the bottom of the periscope such that the beam comes out of the tube straight. (Could align bottom mirror with test laser to ensure it is in the middle of its travel range). Want to make sure the mirror is not so far off that it the beam is hitting the edge of the tube and you are looking at a reflection. This can be confusing.
  7. Do rough alignment of all the gantry periscope mirrors so that the beam remains centered on all of them until the beam hits the first mirror of the entrance periscope.
  8. Add the quarter waveplates before the gantry periscope on the table, and add the entrance quarter waveplate on the vertical breadboard. Set it 45° to the fast axis to make the polarization circular going into the gantry periscope.
  9. Mount camera alignment system onto remote focus objective holder. Align beam to pass through two irises on remote focus alignment jig using two translation stages on beam periscope. Note: this can be a fancy beam profiling system, or a camera coupled to a cheap image acquisition system.
  10. Move gantry system back and forth in y. Adjust top mirror on periscope gantry such that the beam remains stationary on the camera.
  11. Move gantry system back and forth in x. Adjust first mirror inside box (high up) such that the beam remains stationary on the camera.
  12. For rotation need to control four degrees of freedom, so have to move camera between two locations on the vertical breadboard (near) and (far, where it is now). The second location is ideally where quarter waveplate goes (near camera). Have to keep beam centered on both. First keep centered on near camera using far mirror, the one that comes next after one used for x, (high up and closer to vertical breadboard). Then keep centered on far one using mirror at bottom of gantry to keep centered on far one. Watch beam move on camera during move, use mirrors to adjust beam position to be at the center of the curvature of the circle traced out by the beam. THIS CAN BE QUITE TIME CONSUMING - IN PART BECAUSE THE GANTRY ANGLE HAS TO BE MOVES BACK AND FORTH.
  13. Aligned z axis using mirror inside the rotation bearing, keeping beam constant on the camera in the far position.
  14. Add in the other quarter waveplate, set to minimum reflection (maximum transmission) through polarzing beam splitter. Put the card to look at the reflected beam and make it as dim as possible.
  15. Add in the beam expander. There is an iris on the front. Position so that beam goes through it with the whole assembly centered.
  16. Move the entire beam periscope assembly such that the beam is centered on two periscope mirrors. Align periscope through the two irises on the remote focus jig and into the camera using the two translation stages (which should produce pure translation).
  17. Mounting the voicecoil. Remove the remote focus objective so that you don't accidentally damage it. The dowel pins are used to guide the voice coil assembly during mounting, but the exact position of the assembly is set using the nudgers. The lateral position of the beam is adjusted by changing the angle of the voice coil assembly with the two nudgers. Do this while looking at the back reflection on a card near the entrance to the large bearing. The yaw position of the beam is then adjusted by tipping the voice coil assembly. This procedure ensures the mirror is perpendicular to the beam. Look at the beam back near where the quarter waveplate. If you ever see a beam on the card then you know you aren't aligned.
  18. Once the voice coil mirror is aligned remove the voice coil and add remote focus objective back on.
  19. Now set the z position of the voice coil mirror. Add the voice coil back onto the rig









Multistage periscope alignment
Quarter wave plate adjustment for multistage periscope 

Alignment of beam to remote focus objective

Adjustment of quarter wave plates for maximum transmission
Alignment of RF mirror assembly

Alignment of beam to imaging objective using compensators
Adjustment of galvo voltage divider gain
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