The fourth-order index coefficients of GRIN-rod lenses are estimated using the magnitudes of the third-order wave-front spherical aberration reported by Cline and Jander and with the relationship between the third-order wave-front spherical aberration and the fourth-order index coefficient derived for the model of a near one-quarter pitch GRIN-rod lens in a double-pass configuration using the optical path length which is found analytically by algebraic manipulation of the asymptotic solution for the meridional ray equation derived by Streifer and Paxton.
© 1986 Optical Society of America
Toyokazu Sakamoto, "Estimation of the fourth-order index coefficient of GRIN-rod lenses," Appl. Opt. 25, 2613-2619 (1986)