Patent · US Expired

Optical system of variable focal and back-focal length

US4525042A · kind A · utility

10Cited by

2References

5Claims

0Family size

Assignee

Carl Zeiss Stiftung · DE

Inventor

Franz Muchel · Oberkochen, DE

Key dates

Filing date	Jan 5, 1983
Grant date	Jun 25, 1985
Priority date	—
Expiry date	Jan 5, 2003

Classification

Technology area (CPC G)Physics
CPC primaryG02B21/22
WIPO fieldOptics
WIPO sectorInstruments

Abstract

In an optical system of variable focal and back-focal length for operation microscopes, an objective of fixed focal length is combined with an optical system of variable focal length consisting of two lens groups, the first lens group of which is displaceable. The objective projects a real, virtual, or infinity image of the object and the displaceably arranged lens group of the optical system of variable focal length images the image projected by the objective into the focal point of the second lens group of the system. The second lens group consists of two parts which are displaceable in the direction of their optical axis in order to adjust the focal length of the microscope.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.