Abstract

The optimum condition for coupling energy into an optical fiber waveguide is theoretically computed for an incident beam with a Gaussian intensity distribution and a curved wavefront. The dependence of the modal excitation efficiencies on the tilt angle of the incident beam and on the refractive index difference of core and cladding is discussed. Numerical results show that maximum efficiency for the HE₁₁ mode can be achieved when the beam radius is chosen to be approximately 0.65 times the core radius. Excitation efficiencies of low-order modes, HE_1m (m ≥ 2) approach 80% at their cutoff when the beam size is suitably larger than the core diameter.

© 1974 Optical Society of America

Excitation of the Fundamental and Low-Order Modes of Optical Fiber Waveguides with Gaussian Beams. 2: Offset Beams

Masaaki Imai and Elmer H. Hara
Appl. Opt. 14(1) 169-173 (1975)

Mode excitation by tilted and offset Gaussian beams in W-type fibers

Ram Chandra, K. Thyagarajan, and A. K. Ghatak
Appl. Opt. 17(17) 2842-2847 (1978)

Excitation of a doubly clad optical fiber by misaligned Gaussian beams

John C. Cartledge
Appl. Opt. 17(13) 2086-2091 (1978)

Microlenses for Coupling Junction Lasers to Optical Fibers

L. G. Cohen and M. V. Schneider
Appl. Opt. 13(1) 89-94 (1974)

Excitation of an optical fiber by a Gaussian beam

M. Mostafavi, T. Itoh, and R. Mittra
Appl. Opt. 14(9) 2190-2193 (1975)