Abstract

The launching efficiencies of the HE_1m modes and the over-all launching efficiency are calculated for the cases in which a self-focusing optical fiber is excited axially by a TEM_0n beam mode or by a beam consisting of several beam modes. It is shown that, when the fiber is excited by a TEM₀₀ mode whose spot size s is very large compared with the characteristic spot size s_o of the fiber, the HE_1m modes are almost equally excited and that, if s is matched to s_o, the over-all launching efficiency is nearly 100%. The over-all launching efficiency as well as the launching efficiencies of the HE_1m modes decrease considerably when the fiber is excited by a beam containing the TEM₀₁ mode that is out of phase with the TEM₀₀ mode. The effect of the off-axis excitation by a TEM₀₀ mode on the over-all launching efficiency is also examined.

© 1975 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)

Excitation of Fundamental and Low-Order Modes of Optical Fiber Waveguides by Gaussian Beams. 1: Tilted Beams

Masaaki Imai and Elmer H. Hara
Appl. Opt. 13(8) 1893-1899 (1974)

Excitation of an optical fiber by a Gaussian beam

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

Mode conversion coefficients in optical fibers

W. A. Gambling, D. N. Payne, and H. Matsumura
Appl. Opt. 14(7) 1538-1542 (1975)

Radiation losses of the HE₁₁ mode of a fiber with sinusoidally perturbed core boundary

D. Marcuse
Appl. Opt. 14(12) 3021-3025 (1975)