In this paper, we consider the aberrations and design of graded-index (GRIN) rods for use as image relays. Aberration formulas are derived based on the ray path solutions previously published by the authors. The aberrations are then minimized by selecting an optimal radial refractive index variation. We assume no index variation along the axis and also consider only monochromatic aberrations. Design curves and data on the number of resolvable spots are included. The accuracy of the aberration formulas is compared with total aberrations computed numerically.
K. B. Paxton and W. Streifer, "Aberrations and Design of Graded-Index (GRIN) Rods Used as Image Relays," Appl. Opt. 10, 2090-2096 (1971)