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3) Position two silver mirrors such that the beam hits their centers and is steered towards the PPC. Make sure the beam remains level at its original heightThe PPC is designed to accept a beam with a height of 4.75" (which is the beam height of a Coherent Chameleon laser), and s-polarization (which should be the polarization that comes out of the pockels cell modulator). If the beam height needs to be adjusted to enter the PPC, ensure that the polarization state of the beam does not get twisted during the height adjustment. Adjust the beam to make it substantially level WRT the optical table. Do this using an IR card stuck to a support to check beam height at different positions.
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