Search results for "Rating"
showing 10 items of 2021 documents
Investigations of As-S-Se thin films for use as inorganic photoresist for digital image-matrix holography
2011
AbstractAs-S-Se chalcogenide thin films are successfully employed in classical and dot-matrix holography as inorganic photoresists for obtaining a relief-phase hologram. However using these films for image-matrix hologram recording has not been studied due to some features of image-matrix technology. For the applied research of the optical properties of As-S-Se films an experimental device of digital image-matrix holographic recording based on 100 mW 405 nm semi-conductor laser and Spatial Light Modulator (SLM) has been created. The device has the following main parameters: 140 × 105 µm frame size; laser intensity during exposure 10 W/cm2. With the help of this device diffraction grating an…
Holographic Recording of Surface Relief Gratings on As40S60-xSex Thin Films
2015
The studies of direct holographic recording of the surface relief gratings on amorphous As40S60−xSex thin films are presented. These gratings were created upon exposure to polarized laser beams of various wavelengths (λ = 473 – 650 nm). The orthogonally ±45° linearly polarized light beams were used for recording. The surface structure of the relief gratings was investigated by atomic force microscopy. The influence of laser beam wavelength and spatial frequency of the gratings recorded (grating period ?) on the surface relief gratings formation for every composition was examined.
Photoinduced direct surface relief formation in amorphous As40S15Se45 films
2013
Abstract The surface relief grating formation in As40S15Se45 films under He–Ne laser wave-length λ = 0.6328 μm light influence was examined. The obtained experimental results showed the strong dependence of photoinduced surface relief depth on illumination dose and film thickness during holographic recording from film side as well as from glass substrate side. The surface relief grating profile over the thickness range 0.13
Optical Sensor for Real-Time Detection of Trichlorofluoromethane
2019
Trichlorofluoromethane was once a promising and versatile applicable chlorofluorocarbon. Unaware of its ozone-depleting character, for a long time it was globally applied as propellant and refrigerant and thus led to significant thinning of the ozone layer and contributed to the formation of the so-called ozone hole. Although production and application of this substance were gradually reduced at an early stage, we still face the consequences of its former careless use. Today, trichlorofluoromethane is released during recycling processes of waste cooling devices, traded on the black market, and according to recent findings still illegally manufactured. Here, we present an optical sensor devi…
All-fiber lasers actively modelocked by acousto-optic modulation
2010
The development of all-fiber lasers is of high interest because of the intrinsic robustness, compactness and energy efficiency. In-fiber amplitude modulators based on acousto-optic modulation of fiber Bragg gratings (FBG) permit the implementation of novel all-fiber actively modelocked lasers. Using either traveling or standing longitudinal acoustic waves, optical pulses between 500 and 100 mW peak powers and ∼ 700 ps temporal width were obtained at 4.1 and 9 MHz repetition rates, respectively. Implementing a simultaneous active Q-switching, we have demonstrated a doubly active Q-switching and mode-locking of two different all-fiber laser configurations. In the case of the laser based on tr…
Tuning the propagation constant by the anti-crossing bandgap prism coupling technique.
2012
A novel plasmonic structure based on an anticrossing bandgap prism coupling technique is proposed. The study has been carried out using photonic crystals based on diffraction gratings (bounded by dielectrics with identical dielectric functions) together with a high refractive index prism to couple the long-range surface plasmon polaritons to photons. We analyse the structure and demonstrate the ability for tuning the propagation constants of plasmon modes by changing the thickness of the gold grating. The comparison to non-bandgap techniques is studied, and the influence of the plasmonic configuration on the plasmon propagation constant is discussed as well. Experimental measurements were a…
Design and Implementation of Density Sensor for Liquids Using Fiber Bragg Grating Sensor
2022
In this paper, an optical fiber sensor based density sensor is proposed and demonstrated experimentally. The sensor is formed by fiber Bragg grating (FBG) sensor. The proposed sensor design is very simple and versatile for density measurements of liquids. The FBG strain sensor has one end mounted to a 3D printed rigid support, and the other end connected to a 3D manufactured clamp in this sensor design. A metal ball is suspended from this clamp by a non-stretchable cord. When it is completely immersed in liquid, the liquid buoyancy force acts on it. As a result, the strain in FBG varies depending on the force applied to the ball. This results in a wavelength shift in the FBG sensor. The pro…
Abrupt-tapered fiber filter arrangement for a switchable multi-wavelength and tunable Tm-doped fiber laser.
2018
A switchable and tunable multi-wavelength Tm-doped fiber laser is successfully demonstrated using a filter constructed with two tapered fiber elements in the cavity. The proposed system design uses a low-cost simple filter that allows stable dual, triple, quadruple, and quintuple-wavelength emission operation in the region around 1.9 μm. In the dual wavelength regime, the laser is capable of independently tuning each wavelength. For switching and tuning, a curvature is applied to the tapered fibers.
Photoinduced mass transport in low molecular organic glasses and its practical application in holography
2015
Abstract In this paper we present the synthesis and optical properties of amorphous low molecular compound 4-((4-(bis(5,5,5-Triphenylpentyl)amino)phenyl)diazenyl)benzoic acid. The surface relief gratings formation by polarization holography method on these thin films (thicknesses are 200–1700 nm) was shown. The dependence of the surface relief modulation on various parameters: recording exposure dose, the polarization state of the recording beams, the grating period and the film thickness of the material was demonstrated. Values of surface tension at the air-film before and after irradiation of the substance by polarized radiation were measured. The efficiency of surface relief formation in…
<title>Amorphous chalcogenide thin films as a media for holographic recording</title>
2004
The amorphous As2S3 and As40S15Se45 films as a recording media for optical holography and lithography were studied. The results on research of the transmission, surface-relief and Bragg reflection grating holographic recording and readout conditions are presented. The recording of transmission holographic gratings in As40S15Se45 films was performed by He-Ne (0.6328 μm) laser beam, while the redout of the diffraction efficiency was made at Bragg agle using diode (0.805 μm) laser lines. The Bragg reflection gratings in As2S3 films were recorded and studied by Ar+ laser line 0.5145 μm. The surface-relief modulated gratings with a period of 0.15 μm - 1 μm were recorded.© (2004) COPYRIGHT SPIE--…