THORLABS vytran LDC450B User Manual page 17

LDC450B Large Diameter Cleaver Chapter 6: Cleaving
While it is typically preferable to clamp directly on the cladding (bare glass) on the discard side, it is also possible
to center-strip the fiber and to clamp on the buffer. This may be advantageous for certain types of non-circular fiber
that would otherwise rotate uncontrollably during clamping. The "non-discard" side (passing through the left-hand
FHB) should be clamped on the coating whenever possible to avoid potential damage to the glass. The fiber should
be clamped working from one side of the machine to the other. That is to say, if the "non-discard" (left) side is
clamped first, prior to the "discard" (right) side, then all operations should be carried out on the left side before
securing the right side, to minimize the possibility of twisting the fiber during clamping, which would introduce torsion
in to the fiber, and therefore uncontrolled angle.
Figure 10 Two Pieces of Fiber after a Cleave
It is critical that the Cleave Tension be set appropriately for the fiber being cleaved. If the tension is set too low,
the fiber may not cleave and the diamond blade could be damaged due to excessive lateral stresses as the fiber
flexes around the blade. If the tension is too low and the fiber does cleave, the cleave quality will not be very good.
The cleave angle is likely to be high. If the Cleave Tension is set too high, the fiber may break at the clamping
points prior to reaching the desired tension, or, if the cleave is successful, the end face may have excessive
"misting", fracturing and/or roughness.
Rev A, July 28, 2020 Page 13