It is difficult to solve the problem of tracing rays through an inhomogeneous medium such as the atmosphere or a flowing liquid with the existing methods whose refractive distribution cannot be characterized by any combination of formulas. A new method is developed to efficiently describe such a medium. The method essentially consists of characterizing the inhomogeneous medium with a self-adapting grid, the cell size of which can be automatically varied according to the gradient of the refractive index at each position within the medium. The advantage of this method is its capability to trace rays through a medium with random refractive distribution in an accurate way. To test its correctness, the ray trace through a regular gradient medium has also been made with this method, and the results are compared with those from other commercial lens design codes. It is shown that for appropriate parameter settings this method can obtain great accuracy.
© 2007 Optical Society of America
Original Manuscript: November 27, 2006
Revised Manuscript: January 26, 2007
Manuscript Accepted: January 30, 2007
Published: May 15, 2007
Shitao Deng, Xiaotong Li, Zhaofeng Cen, and Shoufu Jian, "Simulation of the inhomogeneous medium with a self-adapting grid," Appl. Opt. 46, 3102-3106 (2007)