A method based on the Herzberger approach has been investigated for the sel
ection of glasses for the apochromatic correction at near-infrared (NIR) wa
velength. The method avoids the algebraic complexity and simplifies the gla
ss selection processes. Doublet and triplet glass combinations can be chose
n directly from the plot of partial dispersion versus V number. Good combin
ations of NIR doublets and triplets are given. Design examples show that th
e method is practical and efficient. (C) 1999 Society of Photo-Optical Inst
rumentation Engineers. [S0091-3286(99)02103-0].