Chapter 6 Theory Of Cleaving; Specialty Fiber Cleaving Processes - THORLABS Vytran LDC401 User Manual

LDC401 & LDC401A Automated Cleavers
Chapter 6 Theory of Cleaving
The LDC401 and LDC401A automated fiber cleavers are designed for cleaving optical fibers with claddings from
Ø80 µm up to Ø1.25 mm. To produce a flat cleave, the cleavers use a "tension-and-scribe" method, whereby an
axial tension is first applied to the fiber followed by an automated Scribe Process utilizing a diamond Cleave Blade.
Figure 7 Pure Tension: Maximum Stress is in the Direction of the Fiber Axis and the Cleave is
The LDC401A is also capable of producing angled cleaves. To accomplish this, a pre-programmed torsion is applied
to the fiber first, followed by axial tension, and then the automated Scribe Process.
Figure 8 Combined Tension and Torsion: Maximum Resultant Stress is at an Angle between the Fiber
When configured and operated properly, both cleavers are capable of producing cleaves with high-quality end-face
finishes.
6.1.

Specialty Fiber Cleaving Processes

Two additional process capabilities are available on the LDC401 and LDC401A. These processes are primarily
utilized for cleaving specialty fibers such as microstructured fiber, highly stressed fibers (MM and PM), or capillary
tubing. The specialty fiber processes are used to produce flat cleaves and improve end face quality but require the
execution of additional steps.
1. Subcritical Process
The "Subcritical Process" applies a tension that is lower than required for a "standard" cleave. The blade
then scribes the fiber, and the tension is slowly (and incrementally) increased to propagate the scribe and
produce the cleave.
2. Micrometer Backstop
The flat micrometer tip acts as a backstop for the fiber during the Cleave Process. When using the
Micrometer Backstop, it is possible to reduce the tension applied to the fiber.
Both of these processes will be described in greater detail in later in the manual.
Rev B, July 19, 2017
Perpendicular to the Axis
Axis and 45° and the Cleave is Perpendicular to this Direction
Chapter 6: Theory of Cleaving
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