THORLABS Vytran GPX4000LZ, Руководство пользователя

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GPX4000LZ Glass Processor Chapter 5: Operation
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reduces the pulling force on the fiber until finally it is no longer stretching it at all. This creates what is called the "up
taper".
This tapering process is in fact similar to a fiber drawing process, where the preform enters the furnace at a slow
velocity and is pulled at a higher rate, creating the smaller diameter fiber. The control of the diameters is achieved
by a precise control of both feed and pull velocities during the process. The next tab in the Taper Properties window
lets the user control the velocity, the taper pull parameters, and the furnace power. It is shown in Figure 35.
Figure 35 Editing Taper Parameters
The values in the "Taper Parameters" window are detailed below.
Furnace Offset:
This will offset the furnace to a desired location at the start of the taper.
It can be used to flame brush the fiber with heat.
Filament Start:
This is the power that the furnace will initially be set to when the taper
process starts.
Filament Delta:
This is the percentage of reduction (negative value) or increase
(positive value) in the furnace power during the tapering process. The
power varies from P at the beginning of the "down taper" to P ±
Δ at the
beginning of the waist and then varies back from P ±
Δ
at the end of the
waist to P at the end of the "up taper"
Filament Delay:
This is the amount of time the furnace is on before fiber holding block
movement (the tensile force) is applied.
Gas Flow Rate:
This is the flow rate of the argon during the tapering process when
using a filament
.
Post-Purge Time:
This is the amount of time argon flows, at the taper rate, after a taper
has been pulled when using a filament.
Pre-Purge Time:
This is the amount of time Argon flows, at the taper rate, before a taper
is pulled when using a filament.
Constant Velocity:
This is the constant speed at which the fiber is fed or pulled through the
furnace during the tapering process.
Time Constant:
The time constant is the time interval at which the software calculates
the velocities to apply to the system in order to achieve the correct
taper. The default value is 0.1 s.
Furnace Move:
This selects the furnace to move, rather than the fiber holding blocks,
during the taper process.