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Absolute distance measurement applying spectrally-resolved interferometry
SPIE Proceedings, 2011A scheme is proposed for high-precision, absolute distance measurement for a theoretical arbitrary optical distance. The approach utilizes a frequency stabilized Ti:sapphirez femtosecond pulse laser to provide a phase-locked summation of discrete quasi-monochromatic light modes of consecutive frequencies, which is seen as an optical comb in the ...
Wei-hu Zhou, Yan Xu, Lei Ding
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Absolute Distance Measurement with a Long Ambiguity Range Using a Tri-Comb Mode-Locked Fiber Laser
Conference on Lasers and Electro-Optics, 2019An absolute distance measurement scheme based on a single triple-comb mode-locked fiber laser is demonstrated. It can realize much longer ambiguity range for real-time measurement with a very simple fiber-optic system setup. © 2019 The Author(s)
Ting Li +6 more
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Photon-counting laser interferometer for absolute distance measurement on rough surface.
Review of Scientific Instruments, 2019We designed a dual-wavelength photon-counting laser interferometer for absolute distance measurement of noncooperative targets. The weak optical interference on the rough surface was measured by a single-photon detector.
Chengkai Pang +6 more
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Absolute distance measurement of rough surfaces using asynchronous optical sampling
Optical Engineering: The Journal of SPIE, 2019. We investigate an optical system for the absolute distance measurement of objects with rough surfaces, using the principle of asynchronous optical sampling (ASOPS).
Wenliang Li +3 more
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Unusual techniques for absolute distance measurement
Optical Engineering, 2001I describe four unusual laser systems for absolute measures of linear distance. All employ the familiar techniques of multiple wave- lengths, chirped wavelength, optical feedback and intensity modulation, but in somewhat unfamiliar architectures. These examples serve to illus- trate the breadth of solutions to this important problem.
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Absolute distance measurement using comb-spectrum interferometry
Journal of Optics, 1998A measurement technique is proposed based on dispersive interferometry using a comb-spectrum source: dispersive comb-spectrum interferometry (DCSI). The configuration proposed processes the Michelson interferometer output by a dispersive grating in the Littrow configuration.
ROVATI, Luigi +3 more
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Absolute distance measurement system using a coherent optical sensor
2012 IEEE International Instrumentation and Measurement Technology Conference Proceedings, 2012This work describes the development of a new optical technique for absolute distance measurements, functioning in safety class 1. By current injection, a wavelength modulation takes place in the laser diode: using a particular algorithm to extract the frequency tone of the fringes induced by the self-mixing effect, it is possible to measure the ...
NORGIA, MICHELE +2 more
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Absolute distance measurement system for precise 3D positioning
Applied Optical Metrology III, 2019We have developed an absolute distance measurement system for the three-dimensional (3D) coordinate measurement. The final project goal is to develop a multilateration based coordinate measuring system for precise 3D positioning. This coordinate measuring system consists of an absolute distance measuring system and four laser tracking stations ...
Seongheum Han +4 more
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Absolute distance measurements using point-diffracted spherical waves
SPIE Proceedings, 2006We describe a novel interferometric scheme that attempts to measure the absolute distance of a three-dimensionally moving target with respect to a reference station. The target transmits two orthogonal pairs of lateral-shearing interferograms generated using four near-perfect spherical waves emitted from single-mode fibers by means of point diffraction.
Jiyoung Chu, Seung-Woo Kim
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Two-point diffraction interferometer for absolute distance measurement
SPIE Proceedings, 2004ABSTRACT We describe a novel method of measuring absolute distances by using a two- point diffraction source specially devised to generate two high quality spherical waves simultaneously with a small lateral offset. Interference of the generated two spherical waves produces a unique ellipsoidal phase distribution in the measurement space A partial map ...
Seung-Woo Kim +3 more
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