title: GRIN'91: gradient-index optical systems.
abstract: The Ninth Topical Meeting on Gradient-Index Optical Systems was held in Monterey, Calif., 8-9 April 1991. In this Introduction we define the scope of the contributions published in this feature issue.
authors: R
authors: R
authors: Srivastava
authors: G
authors: G
authors: Righini
authors: K
authors: K
authors: Iga