Computing formulas are presented for tracing skew rays through optical systems containing cylindrical and toric surfaces of arbitrary orientation and position. Particular attention is given to the treatment of diffraction gratings and a vector form of the diffraction law is suggested.
G. H. SPENCER and M. V. R. K. MURTY, "General Ray-Tracing Procedure," J. Opt. Soc. Am. 52, 672-676 (1962)