Results 181 to 190 of about 3,266 (205)

Ranging and interferometry with a frequency shifted feedback laser

Optics Communications, 2004
The potential advantages of chirped pulses for very precise measurement of distance, through frequency-domain ranging, has prompted consideration of frequency shifted feedback (FSF) lasers as sources of interferometer light. We here derive theoretical limitations to the spatial accuracy one can expect in such applications, by considering analytical ...
L.P. Yatsenko, B.W. Shore, K. Bergmann
openaire   +1 more source

Variability in plant cell water dynamics as a genetic discriminatory method using terahertz quantum cascade laser-based laser feedback interferometry

LASE
In this article, we report our work on the development of a non- invasive, rapid, robust, and high-fidelity technique that can be used to discriminate between genetic variants.
Urbi Kundu, Jari Tornainen, K. Bertling, Mayuri Kashyap, Khushboo Singh, Bogdan C. Donose, T. Gillespie, D. Indjin, Lianhe Li, E. Linfield, A. Davies, Paul Dean, A. Bandyopadhyay, A. Sengupta, A. Rakić   +14 more
semanticscholar   +1 more source

Phase-shifted real-time laser feedback interferometry

SPIE Proceedings, 1996
We have combined the principles of phase-shifting interferometry (PSI) and laser-feedback interferometry (LFI) to produce a new instrument that can measure both optical path length (OPL) changes and discern sample reflectivity variations. In LFI, coherent feedback of the incident light either reflected directly from a surface or reflected after ...
Ben Ovryn, James H. Andrews, Steven J. Eppell, John D. Khaydarov   +3 more
openaire   +1 more source

Phase-measuring feedback interferometry with a tunable laser diode

SPIE Proceedings, 1990
A Twyman-Green phase-measuring feedback interferometer is constructed to calibrate a phase shift which affects the measurement accuracy given by a frequency tuning of a laser diode source. PHASE-SHIFTING LASER-DIODE FEEDBACK INTERFEROMETER Laser diodes (LDs) have been proved to be useful light sources in optical interferornetry for a single-mode ...
Yukihiro Ishii, Ribun Onodera
openaire   +1 more source

Data of the figures in "Laser feedback interferometry in multi-mode terahertz quantum cascade lasers"

, 2020
The characteristics and mappings of three feedback regimes in a multi-mode terahertz quantum cascade ...
X. Qi, G. Agnew, T. Taimre, She Han, Y. Lim, K. Bertling, A. Demić, P. Dean, Dragan Indgin, A. Rakić   +9 more
semanticscholar   +1 more source

A nanometer-resolution displacement measurement system based on laser feedback interferometry

The 8th Annual IEEE International Conference on Nano/Micro Engineered and Molecular Systems, 2013
Based on laser feedback interferometry (LFI) combined with phase-freezing technology (PFT), a novel displacement measurement system is demonstrated, which improves the measurement resolution to nanometer scale. The phase modulator is added to modulate the external cavity phase, and the PFT is used for sampling and demodulation.
Huilan Liu, Heming Yao, Lishuang Feng
openaire   +1 more source

KTP crystal thickness distribution measurements based on laser feedback interferometry

Applied Optics, 2014
KTiOPO(4) (KTP) crystal is a widely used nonlinear optical crystal, and it can meet high requirements for parallelism of crystal surfaces and the length in the light propagation direction in its application fields. In this paper, we present a method for measuring the thickness distribution of cuboid KTP crystals based on laser feedback interferometry ...
Yanxiong, Niu, Haisha, Niu, Ning, Liu, Jiang, Li   +3 more
openaire   +2 more sources

Laser Feedback and New Principle of Heterodyne Interferometry

2006 International Workshop on Laser and Fiber-Optical Networks Modeling, 2006
Among the obstacles of a stable interference pattern in precise long-path laser interferometers the optical feedback through scattering in lasers is insidious. If even the perfect stabilized lasers are used, the accuracy of interference measurements can be aggravated by few orders because of a rather weak optical feedback.
openaire   +1 more source

Quasi-common-path laser feedback interferometry based on frequency shifting and multiplexing

Optics Letters, 2007
We present a quasi-common-path laser feedback interferometer based on frequency shifting and multiplexing. The interferometer uses two acousto-optic modulators to shift the frequency of the target-generated feedback light by 2 Omega. A properly aligned mirror is inserted into the feedback path to generate a feedback light frequency shifted by Omega ...
Xinjun, Wan, Duo, Li, Shulian, Zhang
openaire   +2 more sources

Flow measurement in small channels using laser feedback interferometry [PDF]

, 2015
Imaging flow in small channels for biochemical and biological applications has garnered increasing interest from the research community. Sensitive and accurate measurement and imaging technologies are required whether imaging blood flow in peripheral blood vessels or the flow of reagents in microfluidic circuits.
openaire   +2 more sources