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SolsTiS User Manual v10.0
-
Adjust the horizontal (X) position to the left until the beam can be
seen to start to clip and mark this position on the card.
-
Move the beam to the right, again until the beam begins to clip
and mark this position on the card.
-
Centre the beam in the horizontal and repeat the above for the
vertical axis (Y), marking the maximum displacement the beam
can travel up and down before clipping occurs.
-
Bisect the X and Y points noted above to identify the approximate
centre of the adjustment range.
This will allow the maximum positions that the beam can be moved to
during the process to obtain lasing. Hereafter, under no
circumstances should the beam be moved close to the positions
where clipping occurs.
8.
If no residual green beam is seen, please see the instructions below.
(OPTIONAL) Pump Beam Alignment Optimisation
1.
If you discover or suspect the pump beam is not optimally aligned to the
SolsTiS laser, or you simply want to check pump beam alignment is
optimised, please follow these instructions, which are designed to help
you (re)gain optimal pump beam alignment and SolsTiS output power.
Note!
In general, any pump beam misalignment, if present, is
more likely to be in the HORIZONTAL plane, given that vertical
alignment is usually mechanically constrained by fixed
mounting blocks for both the pump and SolsTiS laser heads.
2.
Secure a white target card ~10 cm from
SolsTiS’ output port.
3.
Turn on the water chiller, if applicable.
4.
Activate the pump laser at low
power (≤0.1W), and then check
for a (typically) faint green spot on the card as an indication that
the pump beam is aligned through the SolsTiS cavity.
5.
If no residual green beam is seen on the card:
a.
Try +/- ¼ turn of the X-axis on the second POM mirror.
b.
If a residual green beam is still not seen on the card, try
+/- ½ turn of the X-axis on the second POM mirror.
6.
Once you have located the residual green pump beam at the
SolsTiS output port, check that this beam is approximately
centred on the SolsTiS output aperture. To do this, adjust the
second mirror to move the residual pump beam across the
SolsTiS output port, observing the points at which clipping of
the pump beam starts. Mark the left hand side and right hand
side clipping points on the target card, and then bisect these
points to identify the approximate centre of this adjustment
range. Centre the residual pump beam on this centre mark.
7.
Set up an IR viewer (or video camera with enhanced ‘night
vision’ IR sensitivity) and aim it at the white target card
positioned at SolsTiS’ output port.
8.
PROVIDED THE RESIDUAL PUMP BEAM EXITING SOLSTIS’
OUTPUT APERTURE DOES NOT APPEAR TO BE CLIPPING,
carefully increase the pump laser output power. Since SolsTiS’
threshold pump power is typically ~2W; set the pump power to
2.5-5W at this stage. (SolsTiS includes internal apertures to
prevent a grossly misaligned pump beam from hitting and
potentially damaging sensitive surfaces in SolsTiS, but take
care not to over adjust the pump beam pointing beyond the
extremes of the SolsTiS output aperture, especially at high
pump power).
9.
While looking through the IR viewer at the card, or the video
camera LCD display, check for SolsTiS laser (a bright IR spot).
If no output is observed, try +/- ¼ turn of the X axis on the
second POM mirror:
a.
If lasing occurs, optimize the pump horizontal position
METHODICALLY, AND IN ONE AXIS ONLY for