Shinn Fwu Wang

A Long Cylindrical Optical Fiber Sensor Based on Multiple Total Internal Reflections in Heterodyne Interferometry

In this paper, a long cylindrical multimode optical fiber sensor (OFS) based on multiple total internal reflections in heterodyne interferometry is proposed. The cladding of the sensing portions of the fiber sensors is removed, but dont be coated with any metal films. With the OFS the phase shift difference due to the multiple total internal reflections (MTIRs) effect between the p-and s-polarizations can be measured by using the heterodyne interferometry. Substituting the phase shift difference into Fresnels equations, the refractive index for the tested medium can be calculated. According to numerical simulations and experimental results, the long cylindrical OFS is with the best resolution of 0.0000028 refractive index unit (RIU). However, the OFS could be valuable for chemical, biological and biochemical sensing. It has some merits, such as, high sensitivity, high resolution, stability, small size and in real-time measurement.

The Response of a Broadband Light Source for an Optical Fiber Sensor Based on Surface Plasmon Resonance Technology

In this paper, the study on response of a broadband light source for an optical fiber sensor (OFS) based on surface plasmon resonance (SPR) technology is presented. The OFS is made of a multimode optical fiber which cladding was removed and coated with two layers of metal films. As a broadband light source is launched into the OFS at a suitable incident angle, we can obtain the intensity at the output of the optical fiber sensor. With the structure, the refractive index detection can be made by the SPR spectra that are obtained by an Optical Spectrum Analyzer (OSA). The OFS could be valuable for chemical, biological and biochemical sensing, etc. It has some advantages, such as, high resolution and stability, small size and real-time measurement.

Design of a Smart Green Energy Management System Based on DMX512 Protocol

In this paper, a smart green energy management system based on DMX512 protocol that is established by United States Institute for Theatre Technology (USITT) is proposed. The end user can monitor and control the LED lamps and electric powers according to the information received from the sensors by means of the channels of DMX512. In addition, the different color lights including red, green, and blue lights can be achieved by means of the color-mixing methods of red, green, and blue LEDs based on photometry theory. As a matter of fact, there have been attracted much attention on the mobile devices in recent years. In the study, a mobile device with an Android platform is used to control the electric power and LED lamps according to the information received from the ZigBee module immediately. However, the smart green energy management system based on DMX512 protocol has some merits, such as in real-time control, easy operation, low cost, etc.

New Type Small-Angle Sensor Based on Multiple Total Internal Reflections and Attenuated Total Reflections in Heterodyne Interferometry

In this paper, a new type small-angle sensor based on multiple total internal reflections and attenuated total reflections in heterodyne interferometry is presented. The small-angle sensor is designed as a reflective elongated prism that is made of BK7 glass. The shorter-side surface of the reflective elongated prism was coated with 2nm Ti-film and 45.5nm Au-film, but the longer-side surface of that was not coated with metal films. With the new type small-angle sensor, the small rotation angle can be obtained only by measuring the phase difference between the p-and s-polarization lights due to the multiple attenuated total-internal reflections (MATRs) and total-internal reflections (TIRs) effects. Its angular resolution can reach 0.000000295 radian at least. The new type small-angle sensor has some merits, e.g., high resolution, high sensitivity, stability, and in real-time test, etc.

Experimental Evaluation of a Small-Displacement Sensing System Based on the Surface Plasmon Resonance Technology in Heterodyne Interferometry

In this article, a small-displacement sensing system based on the surface plasmon resonance technology in heterodyne interferometry is proposed and evaluated. The basic sensing unit is composed of a prism assembly and a displacement probe. The prism assembly consists of a halfwave (λ/2) plate, two right-angle prisms and two rotation stages. The small-displacement sensor is with high sensitivity and resolution due to the attenuated total reflection effect in heterodyne interferometry. Besides, we can obtain the results of the experiment in a distant place by uses of the USB data acquisition card (DAQ card) and a ZigBee module. It can be found that the displacement resolution of the small-displacement sensor can reach 0.155nm by numerical simulation. The small-displacement sensor has some merits, e.g., easy operation, high measurement accuracy, high resolution and rapid measurement, etc.

Pseudo-Interference Technique for Reducing the Mutual Coupling Effects in Adaptive Beamformers

A robust beamformer with pseudo-interference approach for reducing the effect of mutual coupling is present in this paper. This technique uses injected interference to improve the equivalent interference-to-noise ratio in the diagonally loaded Capon beamformer. The mutual coupling coefficients are estimated for interference correlation matrix reconstruction. The resulted beamformer is insensitive to the mutual coupling effects and angular mismatch.

Z-Axis Displacement Sensor Based on Total-Internal Reflection and Surface Plasmon Resonance in Heterodyne Interferometry

In this paper, a z-axis displacement sensor based on Total-Internal Reflection and Surface Plasmon Resonance in heterodyne interferometry is proposed. The sensing unit is composed of a parallelogram prism, i.e. elongated prism, and a displacement probe. One side surface of the elongated prism was coated with a 2 nm Ti-film and a 45.5 nm Au-film, but the other side surface of that were not coated with metal films. The z-axis displacement sensor is with high sensitivity and resolution due to multiple attenuated total reflections and total internal reflections effects. Besides, we can obtain the results of the experiment in a distant place by uses of the USB data acquisition card (DAQ card) and a ZigBee module. In fact, the displacement resolution of the z-axis displacement meter can reach sub-nanometer by numerical simulation. The small-displacement sensor has some merits, e.g., in real-time test, easy operation, high measurement accuracy, high resolution, etc.

Design of a Reflective Type Optical Fiber Sensor Based on Multiple Total-Internal Reflections Theory in Heterodyne Interferometry

In this paper, a reflective type optical fiber sensor (OFS) based on multiple total internal reflections in heterodyne interferometry is proposed. The sensor is made of a multimode optical fiber which cladding was removed and polished as a top shape. And the end surface of the sensor is designed as a micro-mirror. As a heterodyne optical source is launched into the optical fiber sensor at a suitable incident angle, we can obtain the phase difference between s-and p-polarizations at the output of the optical fiber sensor. By numerical simulation, it is clear that the resolution of the system by using the intensity method can reach refractive index unit (RIU) at least in the measurement range of. The OFS could be valuable for chemical, biological and biochemical sensing. It has some merits, such as, high resolution and stability, small size and real-time measurement.

New-Type Biosensor Based on Multiple Total-Internal Reflections in Heterodyne Interferometry

In this paper, a novel biosensor based on multiple total-internal reflections (MTIRs) in heterodyne interferometry (HI) is proposed. The biosensor is made of an elongated prism. As a heterodyne optical light source transmits through the new-type biosensor, it will undergo multiple total-internal reflections (MTIRs). Thus we can obtain the text signal at the output. The phase difference variation due to the different refractive indices of the tested media can be obtained by a Lock-In-amplifier (LIA). By some numerical calculations, we can achieve the related parameters of the tested medium. The resolution of the sensor can reach 4×10-7 refractive index unit (RIU). The electro-optical biosensor has some merits, easy operation, in real-time measurement, and high stability, etc.

Polyhedron Biosensor Based on the Surface Plasmon Resonance Technology in Heterodyne Interferometry

In this article, a polyhedron biosensor based on the surface plasmon resonance technology in heterodyne interferometry is proposed. The sensor is designed as the polygon prism that is made of BK-7 glass with the refractive index of 1.51509. As a heterodyne optical source is launched into the biosensor, the phase difference between s-and p-polarization components can be obtained. The related parameters of the tested medium can be achieved after some calculations. The best resolution of the sensor can reach 5.5×10-7 refractive index unit (RIU). The polyhedron biosensor has some merits, e.g., a simple optical setup, easy operation, high measurement accuracy, high resolution, high sensitivity, and in real-time test, etc.