A brief history of the major advances in microscope optical designs precedes a description of problems facing the designer and the manufacturer. Recent developments to expand the usefulness of the microscope and to make its effectiveness more nearly approach theory are discussed. Attention is given to the various forms the instrument takes when applied to special fields.
L. V. FOSTER, "Microscope Optics," J. Opt. Soc. Am. 40, 275-282 (1950)