Abstract

Interest in reducing the size of glass catalogs has recently resurfaced. Zhang and Shannon¹ used a seven element double gauss to develop a reduced catalog of nine glasses. Smith² varied the flint element in 90 Cooke triplet designs and concluded that a change in Abbe number of ±2 produce a change in lens performance that would be judged acceptable by most lens designers. In contrast to these analyses, Robb³ developed a method of glass selection based on the goal of minimizing secondary spectrum in a thin lens airspaced doublet. His development began by expanding the refractive index in a power series about the chromatic coordinate defined by Buchdahl.⁴ He then developed an algebraic expression based on the coefficients in the power series that was designed to indicate which glass pairs should be selected for polychromatic correction. This investigation attempted to extend the method to a global glass selection technique with the hope of guiding glass catalog offerings.

© 1998 Optical Society of America