Fabrication of Optical Modulator Based on Proton Exchange

<p>For the investigation of optical modulator, the optical wave-guide was fabricated on x-cut LiNbO₃ substrate using proton exchange method with self-aligned electrode. The electrode pattern was designed using a self-aligned thin film electrode method. After proton exchange process, the wave-guide could be prepared by annealing process to control the width and depth of the optical wave-guide. The initial crossover state of the fabricated 1´2 optical switch was observed with controlling the annealing process variables and the structure of self-aligned thin film electrodes. As the results in the present work, the measured cross talk and minimum detectable switching voltage were obtained at the values of -29.5dB and 8.0V, respectively, with good merits.</p>

Optical Fiber Sensor Salt Dense On-Line Monitoring Research

To detect the pollution level of insulators in operation, based on light energy loss theory of medium optical wave guide and mathematical modeling of least squares supporting vector machine, by a lot of contrast tests, this paper designed and developed monitoring terminal of optical sensor. Collecting live temperature, humidity luminous flux attenuation etc. and sending the collected data to data monitoring centre through GSM data communication module, the workstation of data monitoring centre could calculate to get equivalent salt deposit density (ESDD) using mathematical model, so that insulators pollution level can be detected on-line automatically and continuously.

Hysteresis and Viscoelastic Modeling of a Piezo-Optic Voltage Sensor

There is growing interest in sensor technology that is immune to electro-magnetic interference. By nature, development of this technology covers multiple physical domains including electronics, optics, mechanics and materials. This paper discusses development of a mathematical model to compensate for the hysteresis and viscoelastic effects of a piezo-optic voltage sensor. The sensor utilizes piezoelectric fibers with interdigitated electrodes coupled to an optical wave guide via a dielectric matrix. The unknown voltage energizes the piezoelectric fibers to deform fiber Bragg gratings (FBGs) on the waveguide. Therefore, a measurable change in wavelength is related to the unknown voltage. The hysteresis model is based on Rayleigh’s Law of magnetization that is adapted for the coupled piezoelectric and optic response, and the viscoelastic model is based on the standard linear solid model using springs and dashpots in combination. Model results compare favorably with experimental results.

Packaging and Performance of a Piezo-Optic Voltage Sensor

There is growing interest in sensor technology that is immune to electro-magnetic interference. By nature, development of this technology covers multiple physical domains including electronics, optics, mechanics and materials. This paper discusses the design, fabrication and characterization of a piezooptic voltage sensor. The sensor utilizes piezoelectric fibers with interdigitated electrodes coupled to an optical wave guide via a dielectric matrix. The unknown voltage energizes the piezoelectric fibers to deform fiber Bragg gratings (FBGs) on the waveguide. Therefore, a measurable change in wavelength is related to the unknown voltage. The sensor is fabricated using a high quality, repeatable lamination process that does not require the handling of individual piezoelectric fibers. Characterization tests indicate the utility of the sensor in a simulated mission profile. Issues such as hysteresis, creep and optical polarization dependence were also identified.