Patent · US Expired

Determination of the transfer function of an optical instrument

US4772120A · kind A · utility

11Cited by
0References
11Claims
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Assignee

Inventor

Key dates

Filing dateJul 10, 1986
Grant dateSep 20, 1988
Priority date—
Expiry dateJul 10, 2006

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01M11/0292
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

For measuring the optical transfer function of an optical instrument having an input pupil, a device comprises a source of spatially coherent light for illuminating the pupil of the instrument. Two separate zones are isolated in the input pupil of the instrument by a system comprising a grating, a lens for forming an image and a spatial filter which eliminates the zero diffraction order. The two zones have a spacing which is in direct relation to the spatial frequency. The position and mutual spacing of the fringes are determined. A computer derives the transfer function from the measurements made for a plurality of pairs of zones.

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