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Newton’s rings for absolute distance measurement
Optics LettersIn this study, we build upon our earlier research on distance calibration using Newton’s rings [ Opt. Lett. 47 , 6053 ( 2022 ) 10.1364 ...
Josh T. Christensen +5 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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Tunable, double-wavelength heterodyne detection interferometer for absolute-distance measurements
Optics Letters, 1994We present a novel absolute-distance meter based on double heterodyne interferometry. The synthetic wavelength is obtained with a pair of tunable Nd:YAG lasers operating at 1.064 μm. The nonambiguity range of the measurement can be arbitrarily extended by subsequent measurements with different synthetic wavelengths.
E. GELMINI +2 more
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Dual-comb Reciprocal Temporal Scanning for Absolute Distance Measurement
CLEO: 2015, 2015Pulse trains from dual combs with different repetition rates are coupled and directed onto a target for simultaneous absolute distance measurement. Non-ambiguity range extension is immune to drift and accuracy is about 100 nm.
Hongyuan Zhang +3 more
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Laser-diode FMCW technique applied to absolute distance measurement
SPIE Proceedings, 1993A new method for measuring absolute distance is described which is based on the frequency modulated continuous wave (FMCV technique. The preliminary experiment results show that the accuracy can reach 0. 3mx at a distance of 7 meters and the measuring range can exceed 10 meters by using an external cavity laser ...
Mang Cao, Dacheng Li, Yongjun Wu
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Multiple-Wavelength Interferometry for Absolute Distance Measurement
1999Multiple-wavelength interferometry enables an increase in the range of nonambiguity and a reduction in the sensitivity of classical interferometry. It can also be operated on rough surfaces. The accuracy depends on the stability and the calibration of the different wavelengths.
R. Dändliker, Y. Salvadé
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Absolute interferometric distance measurements applying a variable synthetic wavelength
Journal of Optics, 1998This paper describes the principle and design of a first prototype of an absolute distance interferometer using a variable synthetic wavelength. The major components of the prototype are two piezoelectrically tunable diode lasers with an external cavity, and a mechanical dimensional standard.
Karl-Heinz Bechstein, Werner Fuchs
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