Abstract: An optical fiber suitable for use in a single fiber or multifiber optical connector or array is structured with a core region and a cladding region surrounding the core region, and exhibits a bending loss of a fundamental mode of the fiber at a wavelength &lgr; is lower than 0.1 dB/m at a diameter of 15 mm, a mode-field diameter of the fundamental mode at an end of the fiber at the wavelength &lgr; is between 8.0 &mgr;m and 50 &lgr;, and a bending loss of a first higher-order mode at the wavelength &lgr; is higher than 1 dB/m at a diameter of 30 mm. The fiber may be multistructured, wherein the cladding region comprises a main medium and a plurality of sub medium regions therein to form a spatially uniform average refractive index.