Method and apparatus for testing lenses

US4545678A · kind A · utility

Assignee

• Carl Zeiss Stiftung · DE

Inventors

• Wolfgang Grimm · Bremen, DE
• Hermann Schurle · Aalen, DE

Key dates

• Filing date: Jul 1, 1983
• Grant date: Oct 8, 1985
• Expiry date: Jul 1, 2003

Classification

• Technology area (CPC G): Physics
• CPC primary: G01M11/0264
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

The invention concerns a method and apparatus for testing aspherical lenses, particularly continuous-focus eyeglass lenses. The negative picture (7) of a test pattern (1) is produced by means of a master lens (4) which is placed in the ray path of the optical system (6) of the testing device. (FIG. 1). Thereupon the negative picture is projected back onto the test pattern over said ray path, which is now traversed in the opposite direction. If the specimen to be tested is now substituted for the master lens, light edges appear in the plane of the test pattern and give information as to the deviations of the distribution of the refractive power of the test specimen from the desired values of the master lens.