Device and process for testing a lens system
US3930732A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Nov 22, 1974 |
| Grant date | Jan 6, 1976 |
| Priority date | — |
| Expiry date | Nov 22, 1994 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01M11/0292
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
Device and process for testing the optical transfer function of a lens system which comprise employing as the object or target the laterally moving-fringe pattern produced by convergence of two monochromatic coherent-radiation beams of equal size and intensity and slightly different frequency. A second fringe pattern may be employed as the reference standard. Both the target and reference patterns can be varied simultaneously in spatial frequency or fringe period. The system and process can test both modulation transfer function and phase transfer function accurately at any monochromatic wavelength produced by an available coherent-radiation source to which the test lens system is transparent, e.g., ultraviolet or shorter, visible, and infrared or longer. When polarized monochromatic radiation is used, the invention can also be employed to determine the polarization characteristics of the lens. The system and process can also test chromatic aberration by successive use of different coherent monochromatic radiation wavelengths.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.