Laser-cleaving of an optical fiber array with controlled cleaving angle
The present disclosure relates to a process by which an optical fiber array is cleaved with a laser-cleaving apparatus. The coating material is stripped or removed from a section of an optical fiber array; a coated or ribbonized section of the optical fiber array is secured in a holder; the holder is aligned inside the laser-cleaving apparatus; the laser cleaves the stripped ends of the fibers in the optical fiber array; the laser-cleaved ends of the optical fibers are then mechanically separated to remove the free ends from the optical fibers in the optical fiber array, leaving a cleaved array of optical fibers. The cleaving process enables the optical fiber array to be cleaved at flexible locations along an optical fiber ribbon or optical fiber cable with no swelling, minimal cleave angle variation across the cores of the optical fibers, a controlled surface roughness of the optical fiber end-faces, and high process yield.
1. A laser-cleaved optical fiber array comprising:
a plurality of optical fibers, each optical fiber having a fiber end-face including an end-face core, each fiber end-face of the optical fibers having a surface area, the surface area comprising a rough area that defines at least a portion of the surface area, wherein the rough area does not include the end-face core;
wherein the rough area has a surface roughness between 0.1 μm and 0.5 μm root mean squared (rms) as measured by a confocal microscope.
2. The laser-cleaved optical fiber array of claim 1 , wherein for each fiber end-face, a remainder of the surface area that excludes the rough area of the fiber end-face has a surface roughness of less than 10 nm rms.
3. The laser-cleaved optical fiber array of claim 1 , wherein the rough area of each fiber end-face comprises at least 5% of the surface area.
4. The laser-cleaved optical fiber array of claim 1 , wherein the rough area of each fiber end-face comprises over 80% of the surface area.
5. The laser-cleaved optical fiber array of claim 1 , wherein each fiber end-face has a surface roughness of less than 10 nm rms in the end-face core.
6. The laser-cleaved optical fiber array of claim 1 , wherein each fiber end-face has a surface roughness of between 0.1 μm and 0.5 μm rms in the end-face core.
7. The laser-cleaved optical fiber array of claim 1 , wherein for each optical fiber, the fiber end-face has a diameter that is substantially consistent with a diameter of the optical fiber measured at a distance of about 1 mm from the fiber end-face, and wherein the fiber end-face diameter and the optical fiber diameter have a difference of less than 0.2 μm.
8. The laser-cleaved optical fiber array of claim 1 , wherein the end-face core is substantially concentric with a fiber core of the optical fiber measured at a distance of about 1 mm from the fiber end-face, and wherein the end-face core and the fiber core have an offset at the fiber end-face less than 0.1 μm.
9. The laser-cleaved optical fiber array of claim 1 , wherein each fiber end-face is substantially flat with a cleave angle between 0 degrees and 15 degrees relative to a longitudinal axis of each optical fiber.
10. The laser-cleaved optical fiber array of claim 9 , wherein the cleave angle has a cleave angle variation of ±0.5 degrees.