THORLABS Vytran FFS2001 Series User Manual page 57

FFS2001 Series
6.1.2 Fire Polish
When a fusion splice is made, silica will evaporate off of the hot center joint region of the splice and condense on
either side of the joint where the fiber is cooler. These condensed silica deposits, composed primarily of β-SiO
cristobalite, act as stress raisers (flaws) and if the splice is put under tension, the fiber will break at one of these
points. The purpose of the fire polishing process is to remove or minimize these deposits, and thereby improve
splice strength.
Fire polishing is performed immediately after the splice is complete, before the filament is turned off. The splice
head is quickly traversed back and forth along the length of the fiber, such that the hot filament passes over the
regions where the deposits have formed. This quick surface hot treatment reflows the existing deposits without
generating new concentrations.
Setting Up
During purchasing Thorlabs personnel will have advised on your application and configured Splice Files to suit. Be
sure to have the appropriate Splice File loaded for the fiber combination to be processed.
6.2.1 Splice Settings
Splice Parameters: Check the parameters of the 'Splice Parameters' in the 'Splice' menu of the GUI under
•
Splice Parameters. Refer to the table below for typical values.
Parameter
Pre-Gap
Pre-Push
Hot Push
Push Vel
Hot Push Delay
Argon
Splice Offset
On-Duration
Power
Rev. A, August 14, 2024
Fiber Diameter
80 µm
8 µm
5 µm
10 - 14 µm
88 µm/s
0.35 s
0.5 L/min
0 µm
1 - 5 s
15.0 - 17.5 W
Chapter 6: Splicing the Fiber
120 µm
8 µm
5 µm
10 - 14 µm
88 µm/s
0.35 s
0.65 L/min
0 µm
1 - 5 s
18.0 - 23.0 W
or
2
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