Endface Inspection

International standards governing endface defects are poorly defined. Therefore, Fibrepulse has developed its own standard, which is applied in the absence of customer specifications. Because some light can travel in the cladding around the core, there is an exclusion zone where no defects are permitted. This exclusion zone is 25 microns in diameter.

endface-inspection
ZONE A
Defined as an area 25 microns about and including the fibre core. Features allowed are:
Scratches None
Pits/chips/cracks None
Contamination None
ZONE B
Defined as the remaining area of the fibre out to 5 microns from the edge of the fibre. Features allowed are:
Scratches <1 micron in width. Maximum 3 scratches allowed.
Pits/chips/cracks <2 microns diameter.
Contamination None
ZONE C
Defined as the remaining area to the fibre perimeter, 10 microns wide. Features allowed are:
Scratches Unlimited number allowed
Pits/chips/cracks <5 microns diameter
Contamination None
ZONE D
Defined as the rest of the ferrule area, out to 2.5mm diameter. Features allowed are:
Scratches <10 microns wide
Pits/chips/cracks <30 microns diameter
Contamination Engrained contamination only, <30 microns diameter

Although it is necessary to set a minimum standard, as above, for allowable criteria, the vast majority of polished endfaces will greatly exceed this standard. In a recent study at Fibrepulse, 83% of polished endfaces met Zone A requirements across the whole fibre surface. The remaining 17% met Zone A requirements for Area A and B, and were well within the Zone C requirement.