Precision II Operation and Maintenance Manual C
5-12
996-0255 rev. b
D. Oscillator alignment optimization
This section will describe specific procedures for aligning and optimizing
oscillator performance.
Equipment needed:
• Kodak Linagraph paper (type 1895,
CAT#1986108)
• clear plastic bags
• 1 metric Allen wrench set
• Mirror mount adjustment tool
• Styrofoam high density beam block
• Photodiode (~1 ns risetime)
• Fast oscilloscope, >350 MHz with 50 Ω inputs
(seed lasers only)
When the Linagraph (or “burn paper”) is new it will have
a pink emulsion on one side of it. Expose this side to room
light for approximately 30-40 minutes to turn the emul-
sion to a light brown color. Once it's this color the paper
will give the best representation of the laser beam profile.
The back surface of the paper is the one that does not
have the emulsion on it. When taking shots ( or “burns”)
into this side of the paper it is called a “back” burn. Since
the emulsion is very sensitive to the laser energy it tends
to saturate easily. By taking burns through the back of the
paper the energy is attenuated slightly, making interpreta-
tion of the burn pattern easier.
CAUTION:
The output coupler (6 ) should NEVER be adjusted. Mis-
alignment of this optic may necessitate a system realignment
by a factory engineer.
1) Allow the system to warm up to its normal operating
temperature. Activate PGM-1 for ~30 minutes.
2) Take a piece of burn paper (approximately a 3" x 5" strip)
and place it in a plastic bag.
3) Place the paper between the oscillator output coupler (6)
and the first turning mirror (7c) (see diagram, page 5-21).
4) Position the paper so that its back surface is facing the
output of the oscillator (6).
To Next Page
Loading...
Need help?
General