Abstract

For large-core optical fibers of a few meters length, which are typical of those used in beam delivery systems for high-power Nd:YAG lasers, it is shown that the near-field profile of the output beam is a strong function of the launching conditions. The output profile depends on both the input spot size and its alignment relative to the fiber axis. A simple theoretical model is developed for step-index fiber that shows that the output profile depends on the distribution of guided power between meridional modes and groups of skew modes. A relationship is hence derived between the launching conditions and the output profile. The predictions of the theoretical model are consistent with experiment.

© 1992 Optical Society of America

Dependence of output near-field beam profile on launching conditions in graded-index fibers used in delivery systems for Nd:YAG lasers

Alvaro A. P. Boechat, Daoning Su, and Julian D. C. Jones
Appl. Opt. 32(3) 291-297 (1993)

Bend loss in large core multimode optical fiber beam delivery systems

Alvaro A. P. Boechat, Daoning Su, D. R. Hall, and J. D. C. Jones
Appl. Opt. 30(3) 321-327 (1991)

Delivery of 10-MW Nd:YAG laser pulses by large-core optical fibers: dependence of the laser-intensity profile on beam propagation

B. Richou, I. Schertz, I. Gobin, and J. Richou
Appl. Opt. 36(7) 1610-1614 (1997)

Beam quality after propagation of Nd:YAG laser light through large-core optical fibers

Andreas Kuhn, Ian J. Blewett, Duncan P. Hand, and Julian D. C. Jones
Appl. Opt. 39(36) 6754-6760 (2000)

Mode coupling and output beam quality of 100–400 μm core silica fibers

Simon Hurand, Lucam-A. Chauny, Hazem El-Rabii, Sachin Joshi, and Azer P. Yalin
Appl. Opt. 50(4) 492-499 (2011)