Selected Papers Presented at International Meetings
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ICSO 2006 Sixth International Conference on Space
Optics
27 - 30 June 2006
Noordwijk, The Netherlands
Abstract:
The largest limitation of
phase-shifting interferometry for optical testing is the sensitivity to the
environment, both vibration and air turbulence. An interferometer using
temporal phase-shifting is very sensitive to vibration because the various
phase shifted frames of interferometric data are taken at different times
and vibration causes the phase shifts between the data frames to be
different from what is desired. Vibration effects can be reduced by taking
all the phase shifted frames simultaneously and turbulence effects can be
reduced by averaging many measurements. There are several techniques for
simultaneously obtaining several phase-shifted interferograms and this paper
will discuss two such techniques: 1) Simultaneous phase-shifting
interferometry on a single detector array (PhaseCam) and 2) Micropolarizer
phase-shifting array. The application of these techniques for the testing
of large optical components, measurement of vibrational modes, the phasing
of segmented optical components, and the measurement of deformations of
large diffuse structures is described. |
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ICOL 2005 International Conference on Optics &
Optoelectronics
12-15 December 2005
Dehradun, Uttaranchal, India
Abstract: The largest limitation of
phase-shifting interferometry for optical testing is the sensitivity to the
environment, both vibration and air turbulence. In many situations the
measurement accuracy is limited by the environment and sometimes the
environment is sufficiently bad that the measurement cannot be performed.
Recently there have been several advances in dynamic interferometry
techniques for reducing effects of vibration. This paper describes and
compares dynamic interferometry techniques. Dynamic interferometry
techniques for both Twyman-Green and laser-based Fizeau interferometers are
discussed. |
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ICOXX—20th Congress of the International Commission
for Optics
21 - 26 August 2005
Changchun, China (Plenary Presentation)
Abstract: The addition of electronics,
computers, and software to interferometry has provided tremendous
improvements in the measurement of surface shape and roughness. This talk
will describe three such improvements; use of computer generated holograms
for testing aspheric surfaces, techniques for performing interferometric
measurements more accurate than the reference surface, and two single-shot
phase-shifting interferometric techniques for reducing the sensitivity of an
optical test to vibration and measuring dynamically changing surface shapes. |
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Optics and Photonics, SPIE 50th Annual Meeting
31 July – 4 August 2005
San Diego (Banquet Speech)
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Optics and Photonics, SPIE 50th Annual Meeting
31 July – 4 August 2005
San Diego
Abstract: The largest limitation of
phase-shifting interferometry for optical testing is the sensitivity to the
environment, both vibration and air turbulence. In many situations the
measurement accuracy is limited by the environment and sometimes the
environment is sufficiently bad that the measurement cannot be performed.
Recently there have been several advances in dynamic interferometry
techniques for reducing effects of vibration. This talk will describe and
compare two dynamic interferometry techniques; simultaneous phase-shifting
interferometry and a special form of spatial carrier interferometry
utilizing a micropolarizer phase-shifting array. |
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The Optical Society of Korea Summer Meeting
14-15 July 2005
Dan Yang, Korea (Plenary Presentation)
Abstract: The largest limitation of
phase-shifting interferometry for optical testing is the sensitivity to the
environment, both vibration and air turbulence. In many situations the
measurement accuracy is limited by the environment and sometimes the
environment is sufficiently bad that the measurement cannot be performed.
Recently there have been several advances in dynamic interferometry
techniques for reducing effects of vibration. This talk will describe and
compare dynamic interferometry techniques. |
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Laser 2005, World of Photonics
13-17 June 2005
Munich, Germany
Abstract: The measurement accuracy of an
interferometric optical test is generally limited by the environment. This
paper discusses two single-shot interferometric techniques for reducing the
sensitivity of an optical test to vibration; simultaneous phase-shifting
interferometry and a special form of spatial carrier interferometry
utilizing a micropolarizer phase-shifting array. In both techniques
averaging can be used to reduce the effects of turbulence and the normal
double frequency errors generally associated with phase-shifting
interferometry. |
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8th International Symposium on Laser Metrology
14-18 Feb. 2005
Merida, Yucatán, Mexico
Abstract: The largest limitation of
phase-shifting interferometry for optical testing is the sensitivity to the
environment, both vibration and air turbulence. In many situations the
measurement accuracy is limited by the environment and sometimes the
environment is sufficiently bad that the measurement cannot be performed.
This talk discusses advances in reducing effects of vibration by using
dynamic interferometry techniques. |
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OSA Optical Fabrication and Testing (OF&T) 2004
11-13 October 2004
Rochester, NY
Abstract: The measurement accuracy of an
interferometric optical test is generally limited by the environment. This
paper discusses two single-shot interferometric techniques for reducing the
sensitivity of an optical test to vibration; simultaneous phase-shifting
interferometry and spatial carrier interferometry. |
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ASME-ANSI B46-2004 Meeting
8 October 2004
Tucson, AZ
Abstract: The environment generally limits the accuracy of
a phase-shifting interferometry measurement. This
talk discusses the use of simultaneous phase-shifting
interferometry and pixelated phase-mask dynamic interferometry to reduce the
effects of the environment on the measurement. |
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SPIE Annual Meeting 2004
2-6 August 2004
Denver, Colorado
Abstract: We demonstrate a
phase-shifting, point diffraction interferometer that achieves high accuracy
and is capable of measuring a single pulse of
light. The measurement system utilizes a polarizing
point diffraction plate to generate a synthetic reference beam that
is orthogonally polarized to the transmitted test
beam. The plate has very high polarization contrast, works over an extremely
broad angular and spectral range, and is only 100 nanometers thick.
The unique features of the polarizing element make
the system amenable to measuring strongly convergent light from high
numerical aperture optics without the need to use a point reference
source to calibrate the system. Results of
measuring optics with numerical apertures as high as NA 0.8 are presented. |
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SPIE Annual Meeting 2004
2-6 August 2004
Denver, Colorado
Abstract: We demonstrate a new type of
spatial phase-shifting, dynamic interferometer that can acquire
phase-shifted interferograms in a single camera frame. The
interferometer is constructed with a pixelated
phase-mask aligned to a detector array. The phase-mask encodes a
high-frequency spatial interference pattern on two
collinear and orthogonally polarized reference and test beams.
The phase-difference between the two beams can be calculated using
conventional N-bucket algorithms or by spatial
convolution. The wide spectral response of the mask and true common
path design permits operation with a wide
variety of interferometer front ends, and with virtually
any light source including white-light. |
Advanced Interferometric Testing Measurement in the Technology Frontier
(Paper)
Advanced Interferometric Testing Measurement in the Technology Frontier
(Presentation)
ICO'04
2004 ICO International Conference
Optics & Photonics in Technology Frontier
12-15 July 2004
Makuhari Messe, Chiba, Japan
Abstract: The addition of electronics,
computers and software to interferometry has provided enormous improvements
in the measurement of surface shape and roughness. This talk will describe
some of these improvements and how they advanced the technology frontier. |
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Use of Computer Generated Holograms for Testing Aspheric Surfaces
(Paper)
Use of Computer Generated Holograms for Testing Aspheric Surfaces
(Presentation)
ASPE Meeting on Free-Form Optics
4-5 February 2004
Chapel Hill, NC
Abstract: It has been more than 36 years
since Lohmann and Paris first described computer generated holograms (CGHs)
and CGHs have been used to test aspheric optical elements for more than 35
years. Computer generated holograms are now widely used in the testing of
aspheric optical elements and it is expected that their use in aspheric
testing will greatly increase the next few years as the superb measurement
capability of CGHs are better appreciated by more optical manufacturing
personnel. While CGHs are most often used to test rotationally symmetric
surfaces, a great advantage of CGHs is that they can be made for testing
free form optics almost as simply as for testing rotationally symmetric
optics. Crosshairs can be put on the CGH to aid in the alignment of the CGH
and additional holograms can be placed on the CGH to aid in the alignment of
the optics or to aid in calibration of the CGH. CGH interferometers work
well with phase-shifting techniques. |
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Photonics Asia
14-18 October 2002
Shanghai Everbright Convention Center
Shanghai, China
Abstract: Modern electronics, computers, and software have made
interferometry an extremely powerful tool in many fields
including the testing of optical components and optical systems. This
paper will discuss some of the recent advances in
reducing the sensitivity of phase-shifting interferometers to vibration. |
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AeroSense
1-5 April 2002
Gaylord Palms Resort and Convention Center
Orlando, Florida
Abstract: White light interferometry is an extremely powerful tool
for optical measurements. This paper discusses the
advantages and disadvantages of white light interferometry compared to laser
light interferometry. Three different white
light interferometers are discussed; 1. diffraction grating interferometers,
2. vertical scanning or coherence probe
interferometers, and 3. white light scatterplate interferometers. |
