Tsunami - Beckman Institute Laser Resource Center

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Alignment
After each optic is replaced and adjusted, verify the fluorescent cross
created in step 8 below is still evident on the white card. It is important the
steps below be followed in sequence and that each is completed before
starting the next step. The laser will not lase until every optic is replaced
with optics from a single set. If you cannot get the system to lase and you
feel the cavity is misaligned, install the standard optics set (which is easier
to get lasing) and refer to "Cavity Alignmenty' earlier in this chapter to
check the alignment of the system. Once the system lases, repeat this procedure.
If the beam is severely misaligned, realign the cavity. Refer to "Cavity
Alignment" earlier in this chapter.
WARNING
Tsunami should meet specified power for the installed optic set before
changing optic sets. Refer to chapter 7, "Operation: System Start-up,"
and to the specifications listed in Table 3-1 and Table 3-2.
1. Turn off the AOM by pressing the STATUS mode locker enable button
on the Model 3955.
2. Verify the beam is centered on MI, M4, M5, and Mlo.
Perform step 3 if your laser is configured for fs operation, otherwise skip
to step 6.
3. Carefully remove the slit assembly (if present).
a. Close the shutter.
b. Loosen the setscrew that holds the slit assembly to the spindle of
the micrometer (Figure 6-9), then slide the assembly down and
off the micrometer shaft.
WARNING
Support the slit assembly with your hand when loosening the setscrew to
prevent it from falling off and damaging the optics below.
c. Open the shutter.
d. Using the prism dispersion compensation control, adjust the
prism Pr2/Pr3 assembly so the beam is at least 5 mm from the
apex.
4. Replace the high reflector at MI.
Unscrew the high reflector holder, replace the high reflector in the
holder with the appropriate optic for the chosen wavelength, and
screw the holder back in.