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Title: Hybrid shearing and phase-shifting point diffraction interferometer

Abstract

A new interferometry configuration combines the strengths of two existing interferometry methods, improving the quality and extending the dynamic range of both. On the same patterned mask, placed near the image-plane of an optical system under test, patterns for phase-shifting point diffraction interferometry and lateral shearing interferometry coexist. The former giving verifiable high accuracy for the measurement of nearly diffraction-limited optical systems. The latter enabling the measurement of optical systems with more than one wave of aberration in the system wavefront. The interferometry configuration is a hybrid shearing and point diffraction interferometer system for testing an optical element that is positioned along an optical path including: a source of electromagnetic energy in the optical path; a first beam splitter that is secured to a device that includes means for maneuvering the first beam splitter in a first position wherein the first beam splitter is in the optical path dividing light from the source into a reference beam and a test beam and in a second position wherein the first beam splitter is outside the optical path: a hybrid mask which includes a first section that defines a test window and at least one reference pinhole and a second section thatmore » defines a second beam splitter wherein the hybrid mask is secured to a device that includes means for maneuvering either the first section or the second section into the optical path positioned in an image plane that is created by the optical element, with the proviso that the first section of the hybrid mask is positioned in the optical path when first beam splitter is positioned in the optical path; and a detector positioned after the hybrid mask along the optical path.

Inventors:
;
Issue Date:
Research Org.:
Univ. of California, Oakland, CA (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
1174356
Patent Number(s):
6573997
Application Number:
09/617,719
Assignee:
The Regents of California (Oakland, CA)
Patent Classifications (CPCs):
G - PHYSICS G01 - MEASURING G01B - MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS
G - PHYSICS G01 - MEASURING G01M - TESTING STATIC OR DYNAMIC BALANCE OF MACHINES OR STRUCTURES
DOE Contract Number:  
AC03-76SF00098
Resource Type:
Patent
Country of Publication:
United States
Language:
English
Subject:
47 OTHER INSTRUMENTATION

Citation Formats

Goldberg, Kenneth Alan, and Naulleau, Patrick P. Hybrid shearing and phase-shifting point diffraction interferometer. United States: N. p., 2003. Web.
Goldberg, Kenneth Alan, & Naulleau, Patrick P. Hybrid shearing and phase-shifting point diffraction interferometer. United States.
Goldberg, Kenneth Alan, and Naulleau, Patrick P. Tue . "Hybrid shearing and phase-shifting point diffraction interferometer". United States. https://www.osti.gov/servlets/purl/1174356.
@article{osti_1174356,
title = {Hybrid shearing and phase-shifting point diffraction interferometer},
author = {Goldberg, Kenneth Alan and Naulleau, Patrick P.},
abstractNote = {A new interferometry configuration combines the strengths of two existing interferometry methods, improving the quality and extending the dynamic range of both. On the same patterned mask, placed near the image-plane of an optical system under test, patterns for phase-shifting point diffraction interferometry and lateral shearing interferometry coexist. The former giving verifiable high accuracy for the measurement of nearly diffraction-limited optical systems. The latter enabling the measurement of optical systems with more than one wave of aberration in the system wavefront. The interferometry configuration is a hybrid shearing and point diffraction interferometer system for testing an optical element that is positioned along an optical path including: a source of electromagnetic energy in the optical path; a first beam splitter that is secured to a device that includes means for maneuvering the first beam splitter in a first position wherein the first beam splitter is in the optical path dividing light from the source into a reference beam and a test beam and in a second position wherein the first beam splitter is outside the optical path: a hybrid mask which includes a first section that defines a test window and at least one reference pinhole and a second section that defines a second beam splitter wherein the hybrid mask is secured to a device that includes means for maneuvering either the first section or the second section into the optical path positioned in an image plane that is created by the optical element, with the proviso that the first section of the hybrid mask is positioned in the optical path when first beam splitter is positioned in the optical path; and a detector positioned after the hybrid mask along the optical path.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {2003},
month = {6}
}

Patent: