Based on a far-field asymptotic solution of the Helmholtz equation a vector theory to describe the propagation of an off-axis Gaussian wave is developed, the accurate formulas represented in terms of elementary functions are derived, and the propagation properties such as wave spot size and divergence angle are discussed in detail. The applicable range of scalar theory is also presented. A relative error criterion of optical intensity is given by ε = sin<sup>2</sup> α.
© 1999 Optical Society of America
Xiaodong Zeng, Changhong Liang, and Yuying An, "Far-Field Propagation of an Off-Axis Gaussian Wave," Appl. Opt. 38, 6253-6256 (1999)