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Analysis of the Spectral Resolution of a TeO2 based Noncollinear Acousto-Optic Tunable Filter  [PDF]
Chunguang Zhang, Hao Wang, Yishen Qiu
Engineering (ENG) , 2011, DOI: 10.4236/eng.2011.33027
Abstract: The spectral resolution is a main index of evaluating the performance of the designed acousto-optic tunable filter (AOTF). In this letter, an accurate expression of the spectral resolution is presented by considering both the birefringence and the rotatory property of TeO2 crystal. The deduced expression is significant in improving the accuracy of the design of an AOTF and pushing the development of the high-performance AOTF.
The AOTF-based NIR Spectrometer and Its Application in the Pharmaceutical Industry

Sui Linyan,Dong Haiping,Wu Jie,Chen Lei,Zou Zhenmin,
,董海平,吴 杰,陈 雷,邹振民

世界科学技术-中医药现代化 , 2009,
Abstract: Near-infrared spectroscopy (NIR) is rapidly developing as a high-tech analytical technique, with the advantages of high efficiency and on-line analysis, while not destructing any samples. The acousto-optic tunable filter near infrared spectroscopy (AOTF) is introduced here for its principles, technical characteristics, apparatus, applications in the pharmaceutical industry, as welll as its prospect. As usable in quantitative analysis and qualitative identification, testing physical and chemical indicators, and distance on-line detection through the fiber, the near-infrared spectroscopy is a contributing factor in the field of pharmaceutical analysis.
On the resonant optical bistability condition  [PDF]
A. V. Malyshev
Physics , 2012,
Abstract: We address a two level system in an environment interacting with the electromagnetic field in the dipole approximation. The resonant optical bistability induced by local-field effects is studied by considering the relationship between the population difference and the excitation field. The diversity of various systems is included by accounting for the system self-action via the surface part of the Green's dyadic in the general form. The bistability condition and the exact solution of the steady state optical Bloch equations at the absolute bistability threshold are derived analytically.
Acousto-optic laser optical feedback imaging  [PDF]
Olivier Jacquin,Wilfried Glastre,Eric Lacot,Olivier Hugon,Hugues Guillet De Chatellus,Ramaz Fran?ois
Physics , 2012, DOI: 10.1364/OL.37.002514
Abstract: We present a photon noise and diffraction limited imaging method combining the imaging laser and ultrasonic waves. The laser optical feedback imaging (LOFI) technique is an ultrasensitive imaging method for imaging objects through or embedded within a scattering medium. However, LOFI performances are dramatically limited by parasitic optical feedback occurring in the experimental setup. In this work, we have tagged the ballistic photons by an acousto-optic effect in order to filter the parasitic feedback effect and to reach the theoretical and ultimate sensitivity of the LOFI technique. We present the principle and the experimental setup of the acousto-optic laser optical feedback imaging (AO-LOFI) technique, and we demonstrate the suppression of the parasitic feedback.
Optical Spectrometer with Acousto-Optical Dynamic Grating for Guillermo Haro Astrophysical Observatory  [PDF]
Alexandre S. Shcherbakov, Adán Omar Arellanes, Vahram Chavushyan
International Journal of Astronomy and Astrophysics (IJAA) , 2013, DOI: 10.4236/ijaa.2013.34043

Optical spectrometer of the Guillermo Haro astrophysical observatory (Mexico) realizes investigations in the visible and near-infrared range 350 - 800 nm and exploits mechanically removable traditional static diffraction gratings as dispersive elements. There is a set of the static gratings with slit-densities 150 - 600 lines/mm and optical apertures 9 cm × 9 cm that provide the first order spectral resolution from 0.8 to 3.2 A/pixel, respectively. However, the needed mechanical manipulations, namely, replacing the static diffraction gratings with various resolutions and following recalibration of spectrometer within studying even the same object are practically inconvenient and lead to wasting rather expensive observation time. We suggest exploiting an acousto-optical cell, i.e. the dynamic diffraction grating tunable electronically, as dispersive element in that spectrometer. Involving the acousto-optical technique, which can potentially provide electronic control over the spectral resolution and the range of observations, leads to eliminating the abovementioned demerits and improving the efficiency of analysis.

G. Herrera-Martu00EDnez,A. Luna,L. Carrasco,A. Shcherbakov
Revista mexicana de astronomía y astrofísica , 2009,
Abstract: The radio spectroscopy has became a fundamental tool to study astronomical objets at the microwave band. Therefore, the design and construction of instruments with high spectral resolution, low power consumption and compact size for easy handle and transport are necessary. Here we present the design and the tests of an acousto-optical spectrometer for use in solar radio astronomy and for variability studies of cosmic masers sources with a 5 meter antenna (RT5) which is being reinstalled at the Sierra Negra site. We present the rst evaluations of the performance of the components and the laboratory assembly.
Advances and new applications using the acousto-optic effect in optical fibers
Alexandre A. P. Pohl,Roberson A. Oliveira,Ricardo E. Da Silva,Carlos A. F. Marques,Paulo de Tarso Neves Jr.,Kevin Cook,John Canning,Rogério N. Nogueira
Photonic Sensors , 2013, DOI: 10.1007/s13320-013-0100-0
Abstract: This work presents a short review of the current research on the acousto-optic mechanism applied to optical fibers. The role of the piezoelectric element and the acousto-optic modulator in the excitation of flexural and longitudinal acoustic modes in the frequency range up to 1.2 MHz is highlighted. A combination of the finite elements and the transfer matrix methods is used to simulate the interaction of the waves with Bragg and long period gratings. Results show a very good agreement with experimental data. Recent applications such as the writing of gratings under the acoustic excitation and a novel viscometer sensor based on the acousto-optic mechanism are discussed.
Optical bistability of graphene in the terahertz range  [PDF]
N. M. R. Peres,Yu. V. Bludov,Jaime E. Santos,Antti-Pekka Jauho,M. I. Vasilevskiy
Physics , 2014, DOI: 10.1103/PhysRevB.90.125425
Abstract: We use an exact solution of the relaxation-time Boltzmann equation in a uniform AC electric field to describe the nonlinear optical response of graphene in the terahertz (THz). The cases of monolayer, bilayer and ABA-stacked trilayer graphene are considered, and the monolayer species is shown to be the most appropriate one to exploit the nonlinear free electron response. We find that a single layer of monolayer graphene shows an optical bistability in the THz range, within the electromagnetic power range attainable in practice. The current associated with the third harmonic generation is also computed.
Acousto-optical coherence tomography with a digital holographic detection scheme  [PDF]
Michel Gross,Fran?ois Ramaz,Emilie Benoit,Emmanuel Bossy,Salma Farahi
Physics , 2012, DOI: 10.1364/OL.37.003216
Abstract: Acousto-optical coherence tomography (AOCT) consists in using random phase jumps on ultrasound and light to achieve a millimeter resolution when imaging thick scattering media. We combined this technique with heterodyne off-axis digital holography. Two-dimensional images of absorbing objects embedded in scattering phantoms are obtained with a good signal-to-noise ratio. We study the impact of the phase modulation characteristics on the amplitude of the acousto-optic signal and on the contrast and apparent size of the absorbing inclusion.


物理学报 , 1985,
Abstract: In this paper, the measurement on optical bistability and non-linear trasmission of InSb at 12 K is described and an analysis based on theory of optical bistability of Fabry-Perot cavity is given.
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