Phase-shifting point diffraction interferometer mask designs

Patent · Mon Jan 01 04:00:00 EST 2001

OSTI ID:874077

Goldberg, Kenneth Alan ^[1]

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1. Berkeley, CA

In a phase-shifting point diffraction interferometer, different image-plane mask designs can improve the operation of the interferometer. By keeping the test beam window of the mask small compared to the separation distance between the beams, the problem of energy from the reference beam leaking through the test beam window is reduced. By rotating the grating and mask 45.degree., only a single one-dimensional translation stage is required for phase-shifting. By keeping two reference pinholes in the same orientation about the test beam window, only a single grating orientation, and thus a single one-dimensional translation stage, is required. The use of a two-dimensional grating allows for a multiplicity of pinholes to be used about the pattern of diffracted orders of the grating at the mask. Orientation marks on the mask can be used to orient the device and indicate the position of the reference pinholes.

• Research Organization: Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA
• DOE Contract Number: AC03-76SF00098
• Assignee: The Regents of the University of California (Oakland, CA)
• Patent Number(s): US 6307635
• OSTI ID: 874077
• Country of Publication: United States
• Language: English

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