Phase-shifting point diffraction interferometer focus-aid enhanced mask

Title: Phase-shifting point diffraction interferometer focus-aid enhanced mask

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Abstract

A phase-shifting point diffraction interferometer system (PS/PDI) employing a PS/PDI mask that includes a PDI focus aid is provided. The PDI focus aid mask includes a large or secondary reference pinhole that is slightly displaced from the true or primary reference pinhole. The secondary pinhole provides a larger capture tolerance for interferometrically performing fine focus. With the focus-aid enhanced mask, conventional methods such as the knife-edge test can be used to perform an initial (or rough) focus and the secondary (large) pinhole is used to perform interferometric fine focus. Once the system is well focused, high accuracy interferometry can be performed using the primary (small) pinhole.

Inventors:

Naulleau, Patrick ^[1]

5239 Miles Ave., Apt. A, Oakland, CA 94618

Publication Date:: 2000-01-01

Research Org.:: Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

OSTI Identifier:: 873397

Patent Number(s):: US 6151115

Assignee:: Naulleau, Patrick (5239 Miles Ave., Apt. A, Oakland, CA 94618)

DOE Contract Number:: AC03-76SF00098

Resource Type:: Patent

Country of Publication:: United States

Language:: English

Subject:: phase-shifting; diffraction; interferometer; focus-aid; enhanced; mask; pdi; employing; focus; provided; secondary; reference; pinhole; slightly; displaced; true; primary; provides; larger; capture; tolerance; interferometrically; performing; fine; conventional; methods; knife-edge; perform; initial; interferometric; focused; accuracy; interferometry; performed; diffraction interferometer; conventional methods; reference pinhole; pdi mask; pdi focus; /356/

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                    Naulleau, Patrick. Phase-shifting point diffraction interferometer focus-aid enhanced mask.  United States: N. p., 2000. 
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                    Naulleau, Patrick. Phase-shifting point diffraction interferometer focus-aid enhanced mask.  United States.

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                    Naulleau, Patrick. Sat .  
        "Phase-shifting point diffraction interferometer focus-aid enhanced mask".  United States.  https://www.osti.gov/servlets/purl/873397.

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@article{osti_873397,

  title        = {Phase-shifting point diffraction interferometer focus-aid enhanced mask},

  author       = {Naulleau, Patrick},

  abstractNote = {A phase-shifting point diffraction interferometer system (PS/PDI) employing a PS/PDI mask that includes a PDI focus aid is provided. The PDI focus aid mask includes a large or secondary reference pinhole that is slightly displaced from the true or primary reference pinhole. The secondary pinhole provides a larger capture tolerance for interferometrically performing fine focus. With the focus-aid enhanced mask, conventional methods such as the knife-edge test can be used to perform an initial (or rough) focus and the secondary (large) pinhole is used to perform interferometric fine focus. Once the system is well focused, high accuracy interferometry can be performed using the primary (small) pinhole.},

  doi          = {},

  url          = {https://www.osti.gov/biblio/873397},
  journal      = {},
number       = ,

  volume       = ,

  place        = {United States},

  year         = {2000},

  month        = {1}

}

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