Design and analysis of low bend losses of the air core optical fiber for wavelength selective devices

In this paper, the bending loss, modal field diameter and the modal field distribution of the air core optical fiber are investigated. The effect of optical and geometrical parameters on the bending loss, power confinement and modal field diameter are examined in this special fiber. Detailed design parameters and operation principles of the air core optical fiber are discussed. The structure is based on a unique three layered structure of air core optical fiber, having the central air core, germanium silicate ring core, and silica cladding. It has been demonstrated that air core optical fiber has an excellent mode transformation capability. The air core optical fiber is expected to have a versatile application in local area optical communication networks and tunable wavelength selective devices. The main advantages of air core optical fiber are low bend loss and small mode field diameter, which is a prime focus of this paper.