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Search Publications by: John R. Lawall (Fed)

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Displaying 26 - 46 of 46

How Accurately Can Your Interferometer Interpolate Fringes?

September 1, 2001
Author(s)
John R. Lawall
Optical interferometry is the means by which real-world displacements are measured relative to a standard reference wavelength. Most interferometers use a helium-neon laser and generate a signal with a period of half the wavelength, λ/2=316.5 nm. To

Ultrastable Laser Array at 633 nm for Real-Time Dimensional Metrology

July 1, 2001
Author(s)
John R. Lawall, J Pedulla, Y LeCoq
We describe a laser system for very high-accuracy dimensional metrology. A sealed-cavity helium-neon laser is offset-locked to an iodine-stabilized laser in order to realize a secondary standard with higher power and less phase noise. Synchronous averaging

Design and Evaluation of A Simple Ultralow Vibration Vacuum Environment

January 1, 2001
Author(s)
John R. Lawall, Ernest G. Kessler
A vibration-isolated platform in a high-vacuum environment designed for prototyping optical interferometers is described. The system provides isolation from both seismic and acoustic disturbances with a residual acceleration of 2.9 x 10 -6 m/s 2 rms (root

Ultrastable Laser Array at 633 nm for Real-Time Dimensional Metrology

January 1, 2001
Author(s)
Y Lecoq, J Pedulla, John Lawall
We describe a laser system for very high-accuracy dimensional metrology. A sealed-cavity helium-neon laser is offset-locked to an iodine-stabilized laser in order to realize a secondary standard with higher power and less phase noise. Synchronous averaging

Michelson Interferometry With 10 PM Accuracy

July 1, 2000
Author(s)
John R. Lawall, Ernest G. Kessler
We demonstrate a new heterodyne Michelson interferometer design for displacement measurements capable of fringe interpolation accuracy of one part in 36,000. Key to this level of accuracy are the use of two accousto-opic modulators for heterodyne frequency

A Frequency Stabilized Laser Array for Use in Displacement Metrology

February 17, 2000
Author(s)
J Pedulla, R Deslattes, John R. Lawall
We have developed a frequency stabilized laser system to supply light to measure atomic-scale displacements of a stage moved in real time. Each laser in the array provides enough power (~1 mW) for four Michelson interferometers whose accuracy requires a

A Frequency Stabilized Laser Array for Use in Displacement Metrology

February 1, 2000
Author(s)
J Pedulla, R Deslattes, John R. Lawall
We have developed a frequency stabilized laser system to supply light to measure atomic-scale displacements of a stage moved in real time. Each laser in the array provides enough power ({approximately equal to} 1 mW) for four Michelson interferometers

A Heterodyne Interferometer With Subatomic Periodic Nonlinearity

September 1, 1999
Author(s)
C M. Wu, John R. Lawall, R Deslattes
A new to our knowledge heterodyne interferometer for differential displacement measurements is presented. It is, in principle, free of periodic nonlinearity. A pair of spatially separated light beams with different frequencies is produced by two acoustic