Feature

Low Magnification Parfocal Microscope Objective

J. Brian Caldwell

At first glance it would seem that the design of an ultra-low-power microscope objective of about 2x magnification would be a trivial task. The required focal length is on the order of 70-100 mm, which is large compared to high power microscope objectives, but modest compared to many photographic objectives, and the NA need only be about 0.1. However, microscope objectives are usually designed to work in sets of three or four different focal lengths, all mounted to a turret.

Publish Date: 01 September 1998