CAL & ADJUST
3-8
VersaPulse Select Service Manual
0621-499-01 03/94
®
®
The channel HR and OC must first be aligned to each other through the length of the YAG rod in order to achieve
lasing. Once the two mirrors are aligned to provide a usable output (will make a burn on photopaper), the two
optics are adjusted together to "walk" the YAG output so that it is centered in the first relay mirror. Finally, the
HR is adjusted to peak the power out of the cavity into the center of the first relay mirror.
The channel first and second (plano) relay mirrors are adjusted to center the channel YAG beam through the
wedge optics and into the center of the fiber port. The first relay mirror is the fine adjustment (it is concave, and
provides less positional change to the beam downstream at the fiber port). The second relay mirror is a gross
adjustment, it moves the beam much more than the first relay mirror. In general, unless the beam is grossly out
of center at the second wedge aperture, the second relay mirror should not be adjusted.
There are also two turning mirrors that steer all the YAG channels off the servo mirror down towards the fiber
port. These mirrors do not normally require adjustment. Obviously, adjusting one of these mirrors will affect all
four YAG channels. The adjustment and mounting scheme is the same as that for the channel optics.
3.4.3 YAG Channel Check Out and Adjustment Procedure
1. Remove the optics bench cover.
2. Examine the optics for any visual sign of damage. Replace damaged HR, OC, or Relay mirrors.
To replace a channel relay mirror, HR, or OC, first remove the mirror mount by carefully removing
the mounting screw (it has a spring around its shaft to place tension on the mount) while supporting
the mount. Once the mount is free, set it down face up and remove the retainer (held in place by
three hex head screws) that hold the optic. The old optic can then be removed and the new optic
inserted (five ball bearings inside the mounting hole center the optic in the hole). Reinstall the
retainer, then the mirror mount. Note that the mount should return to its former position, since the
adjustment screws were not moved.
3. Examine the end of the rod for visual damage.
The rod will be illuminated by the flash lamp when the unit is on (if not, the flash lamp has failed or
the simmer supply circuitry has a problem). Replace a damaged rod or failed flash lamp by replacing
the brick assembly.
4. Center and peak the cavity output into the first relay mirror.
When the cavity OC and HR are correctly aligned the YAG beam will be centered in the relay mirror
directly across from the OC, and the cavity power output will be peaked.
a.) Remove the first relay mirror mount and install the cross hair aperture (as described in
3.4.1).
b.) Make a burn (single channel) through the cross hair aperture onto a piece of burn paper.
c.) Examine the burn to determine if the YAG beam is centered.
12/95
To Next Page
Loading...