Anti-resonant hollow core optical fiber with recessed cladding tube

Abstract

An anti-resonant hollow core optical fiber including: (A) a fiber longitudinal axis extending from a first end to a second end; (B) a cladding tube through which the fiber longitudinal axis extends, the cladding tube (1) extending longitudinally from the first end to the second end, (2) disposed azimuthally around the fiber longitudinal axis, and (3) including (a) a cladding outer surface at a cladding outer radius from the fiber longitudinal axis and (b) a cladding inner surface comprising at least one recess; and (C) at least one anti-resonant element in contact with the cladding inner surface, the at least one anti-resonant element extending longitudinally from the first end to the second end. The cladding inner surface is disposed at a cladding inner radius that has azimuthal variability (e.g., is not constant entirely) around the fiber longitudinal axis to define the at least one recess.

Dependencies are inferred from the claim text.