Thermal Core Expansion; Fiber Lensing; Mode Adaptors; Pump Combiners And Couplers - THORLABS Vytran GPX3400 User Manual

GPX3400 and GPX3600 Glass Processors

5.7.7. Thermal Core Expansion

Thermal core expansion can be accomplished on the glass processors by executing a standard splice with
modified fire polish parameters. To prepare for thermal core expansion, open the Splice menu and click on the
Fire Polish Parameters tab. Typical fire polish parameters for thermal core expansion of Ø125 µm cladding fiber is
shown in Figure 20. For splice loss optimization via this method, the fire-polish process can be executed multiple
times.
For thermal core expansion, delta, number of passes, and scan velocity need to be optimized to reach the best
result. Power should be the same or slightly higher than the splice power. Please note: these values are filament
and fiber specific. For further assistance,please contact Thorlabs.
Once these changes have been made, load the fiber with the stripped region centered at the splice head. Click
the "Splice" button, and the glass processor will perform the thermal core expansion.
Figure 20 Editing Fire Polish Parameters in Preperation for Thermal Core Expansion

5.7.8. Fiber Lensing

There are many different types of fiber lensing applications. Some involve splicing a component onto the end of a
fiber, some involve altering the end of a fiber, and some involve splicing a component onto the end of a fiber and
then altering it using the furnace. Users are advised to contact Thorlabs for assistance in these matters.

5.7.9. Mode Adaptors

Fiber laser systems typically employ large-mode-area, double-clad gain fibers that must be coupled to a wide
variety of dissimilar fibers. In order to optimize the signal and/or pump coupling between dissimilar fibers, a mode
adaptor is often used to manage the transition This technique is rather specialized, and glass processor users
wanting to fabricate mode adaptors are advised to contact Thorlabs for assistance with their projects.

5.7.10. Pump Combiners and Couplers

The glass processor workstation can be used to fuse fibers side-by-side or into bundle configurations, which is the
fundamental process for the fabrication of fused tapered couplers and pump or output combiners. However, this is
a highly specialized application and users are advised to contact Thorlabs for assistance.
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Chapter 5: Operation
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