MOGlabs MOA, Manual, Page: 30 / 66

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Chapter 5. MOA: external seed alignment
A
D C B
OUTPUT
ISOLATOR
CYL
LENS
TA DIODE
M2
M3
M4
OPTIONAL
INPUT
ISOLATOR
M1
OPTIONAL λ/2
OPTIONAL λ/2
OPTIONAL
FIBRE
INPUT
OPTIONAL λ/2 OPTIONAL λ/2
OPTIONAL
FIBRE
OUTPUT
Figure 5.1:
Schematic diagram of major components in the
MOA
.
to avoid normal incidence reflections.
NOTE: If a sufficiently slim power sensor is not available, insert a
mirror in the beam path after the output isolator (preferably, other-
wise before the isolator) to deflect the beam to a larger sensor.
3. Power on the
TA
diode with an injection current of 100 mA less than
the
Maximum current, unseeded
. The
TA
injection current should
be chosen to match one of the values in the table
Guide for seed
coupling at low and high tapered amplifier current
from column
TA
current (mA)
on the test report, but still be below
Maximum current,
unseeded
.
NOTE: The
TA
diode injection current should not be more than
Max-
imum current, unseeded
(see test report).
NOTE: Do not allow the
TA
reverse propagating beam to propagate
into the seed laser without an isolator installed between the two
diodes; it could damage the seed laser diode.
4. Adjust the seed laser current/power so that the power immediately
before the
TA
diode matches a listed value from the table
Guide
for seed coupling at low and high tapered amplifier current
in the