Educação matemática pela arte
Gusmão, Lucimar Donizete
2013-08-28
Search results
26 records were found.
A method is presented for the simultaneous measurement of the real and imaginary parts of the refractive indices of absorbing media using an integrated-optical sensor
An inexpensive and robust method for acquiring multiple outputs from integrated optical sensor devices using a 1D CCD array is described in this paper. An example is gven of the development of an instrument based on the use of an integrated optical Mach-Zehnder interferometer (MZI) refractive index transducer. The technique is especially promising for application to multianalyte sensors where several outputs need to be interrogated simultaneously. The high sensitivity and low noise demonstrated by the system will enable the use of cheap, stable LED light sources in practical instruments. Introduction: Integrated optical transducers for the real-time measurement of interactions between biological molecules and for the specific detection of chemical and biochemical species are the subject of growing interest. Applications of this techno...
Integrated optical transducers for the detection of chemical and biochemical species and for optical measurements on bulk media are the subject of intense research effort. While many such sensors have been demonstrated in research laboratories worldwide, commercial exploitation of integrated optical sensors has proceeded slowly. Progress towards incorporating multiple-output sensors, based around the use of integrated optical Mach-Zehnder interferometers (MZIs), into a robust and inexpensive instrument is described in this paper. A 1D CCD array is used to acquire the multiple outputs, resulting in ready alignment and a flexible approach to device reconfiguration and offering particular promise for application to multianalyte transducers where several signals must be interrogated simultaneously. The sensitivity and low noise demonstrate...
A novel integrated optical sensor based on an asymmetric directional coupler structure is described. A patterned low-index fluoropolymer film is used to define the sensing region. The response of the device with respect to small changes in refractive index is demonstrated, and its potential for detecting antibody-antigen reactions is considered
The fabrication and operation of robust integrated optical refractometers, suitable for precise measurements of small changes without ambiguity over a wide range of refractive indices, is described. The design primarily uses an optical fibre coupled dual-sensitivity integrated optical Mach–Zehnder interferometer (MZI) sensor chip incorporating 3×3 directional coupler combiners and internal referencing. High-index tantalum pentoxide (Ta2O5) films were deposited on the waveguide surface in order to increase sensitivity and measurements of their response to liquid analyte index have been carried out by passing aqueous sucrose solutions over the sensor surface. These devices are intended for application as high-sensitivity multi-purpose chemical sensors and bio-sensors.
The optimization of potassium ion-exchanged optical waveguides in glass for evanescent field propulsion of colloidal gold nanoparticles is reported. Velocity dependence upon ion-exchange parameters is given and a maximum velocity of 8 μm/s was achieved for 10-40 nm radius particles with 500 mW modal power at 1.047 μm.
The optimization of potassium ion-exchanged optical waveguides in glass for evanescent field propulsion of colloidal gold nanoparticles is reported. Velocity dependence upon ion-exchange parameters is given and a maximum velocity of 8 μm/s was achieved for 10-40 nm radius particles with 500 mW modal power at 1.047 μm.
The fabrication and operation of robust integrated optical refractometers, suitable for precise measurements of small changes without ambiguity over a wide range of refractive indices, is described. The design primarily uses an optical fibre coupled dual-sensitivity integrated optical Mach-Zehnder Interferometer sensor chip incorporating 3x3 directional coupler combiners and internal referencing. High-index Ta2O5 films were deposited on the waveguide surface in order to increase sensitivity and measurements of their response to liquid analyte index have been carried out by passing aqueous sucrose solutions over the sensor surface. These devices are intended for application as high-sensitivity multi-purpose chemical sensors and biosensors.
Introduction
The principal contribution of Southampton University to the BIOPTICAS project is in the realization of planar optical waveguide probes to determine the optical properties of attached sensing films. Three types of device are being investigated: surface plasmon resonance(SPR), directional coupler and chemiluminescence sensors. Techniques have been established for the deposition of compatible electrodes for electrochemical modulation of sensing reactions as an integral part of devices, and equipment has been set up for the fabrication of waveguides in glass substrates by field-assisted ion-exchange. The modelling and design stages for the devices are now close to completion, and we have begun the fabrication and evaluation of preliminary designs and verification of models. Interaction with partners has resulted in the establ...
The optimization of potassium ion-exchanged optical waveguides in glass for evanescent field propulsion of colloidal gold nanoparticles is reported. Velocity dependence upon ion-exchange parameters is given and a maximum velocity of 8 m/s was achieved for 10–40 nm radius particles with 500 mW modal power at 1.047 m.
