Chapter 3: Tuning and Testing Procedures
© 2019 Cutting Edge Optronics
33
Patara II and Iklwa II Service Manual
Figure 2-26: Finished SHG assembly
12.
Inspect the crystal surface for cleanliness under a 10x microscope. Remove
any debris using nitrogen or clean, dry air.
13.
Bridge tack ball plungers with 2216 epoxy.
14.
Install the top mount with new SHG crystal into the laser. Align the assembly
so the face of the crystal is perpendicular to the beam path. Don’t tighten the
three #8 screws at this moment. Connect the assembly to the TEC Controller.
15.
Remove the aperture assembly.
16.
Turn on the chiller. Set the Q Switch to parameters specified on the ATP Test
Report Data Summary. Open the shutter. Set the drive current slightly above
the threshold. Set the TEC temperature at 30ºC for the starting point.
17.
Verify the beam hits the center of the SHG crystal. See Figure 2-28 for ideal
alignment. Base screws can be loosened to center the beam through the SHG
crystal.
18.
See
Figure 2-27
. If reflections are not vertical, rotate the top of the SHG
assembly so the satellite beams seen on the power meter detector overlap the
main laser beam as shown in
Figure 2-27
.
19.
See
Figure 2-27
. Place a shim with proper thickness between the SHG
assembly base and the laser bench to make the beams overlap in the vertical
direction as shown in
Figure 2-27
. Loosening the base screws will be
required. Tighten all the screws for the SHG assembly and top mount.