Continuum Surelite EX 10, Operation And Maintenance Manual

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Continuum Surelite Laser
92 996-0207
Beam alignment
Beam alignment involves adjusting steering optics (10a), (10b), (13a) and (13b) only.
Adjust neither the wave plates (9) and (3) nor the dielectric polarizer (11), nor the position
of the crystal oven (12). Perform this procedure only if misalignment is obvious.
1. Allow both lasers about 20 minutes to reach thermal equilibrium.
2. Attenuate both 532 nm beams, either by reducing their Q-switch delays, reducing
their flashlamp voltages, or detuning the crystal. Wear goggles to further attenuate
the green light.
3. Fire laser A at its normal repetition rate, and set laser B to single shot operation.
4. Steer laser A beam to the PIV experiment with dichroics (13a) and (13b).
5. Place a white target (e.g. a business card) 5 to 500 cm after the PIV beam exit, and
observe the laser A spot. Firing laser B will show a second spot nearby. Use mirror
(10a) to overlap both spots.
6. Place the white target as far as possible (but not farther than two meters) beyond
its previous position. Use mirror (10b) to completely overlap these two beams.
7. Repeat the above two steps until the beam overlap is satisfactory. Additional
output steering using dichroics (13a) and (13b) will not affect the overlap.
8. Restore both lasers to full power operation, and optimize the crystal angle if output
power is low.
9. Engage both intracavity shutters.