Microscope objective

摘要

An objective for a microscope has a meniscus lens of positive power at one end of the objective. A lens of negative power is located at the other extremity of the objective. Three intermediate doublets of positive power are located between the first two lenses each formed of a convergent lens cemented to a divergent lens. The meniscus lens situated at the front has focal length between 1.5f and 2.5f. The lens of negative power is a doublet formed of a convergent lens and a divergent lens with a focal length between -8f and -15f. The first doublet located close to the lens of negative power has a focal length between 14f and 18f. The second doublet situated immediately before the first doublet has a focal length between 6f and 8f. The third doublet located between the second doublet and the meniscus lens at the front end of the objective has a focal length between 3f and 4f.