Optical sensors based on Fabry-Perot interferometer to detect cadmium ions is proposed. The sensor was fabricated by coating the tip of the optical fiber by chitosan. The two chitosan surfaces serve as mirrors which form a Fabry-Perot interferometer. The characterization results indicate that the sensor has a linear response with sensitivity of 0.0884 dBm/ppm with a correlation factor of 0.9665...

This paper describes the fabrication of a novel type of pressure sensor based on optical feedback in a Vertical Cavity Surface Emitting Laser (VCSEL). The detection mechanism of the sensor is based on a displacement measurement through self-mixing interferometry in the laser cavity. The use of unpackaged VCSELs enables the embedding in thin flexible optical foils which results in an integrated ...

Magnetic sensor macrospheres (MagSeMacs), i.e., stainless steel spheres coated with optical chemical sensors, are presented as an alternative to existing optical sensor patches and fiber-optical dip-probes. Such spheres can either be reversibly attached to the tip of an optical fiber (dip-probe) or trapped inside a vessel for read-out through the side wall. Moving the magnetic separator at the ...

A novel optical sensor has been proposed for sensitive determination of bismuth ion basedon immobilization of 4-(4-nitrophenylazo)-1-naphthol on a triacetylcellulose membrane.Chemical binding of bismuth ions in solution with a 4-(4-nitrophenylazo)-1-naphtholimmobilized on the triacetylcelluse surface could be monitored spectrophotometrically. Theoptode shows excellent response over wide concent...

A comparative study on the sensing properties of a tapered optical fiber pristine and functionalized with the palladium nanoparticles to hydrogen and volatile organic compounds (VOCs), is presented. The sensor response and, response/recovery times were extracted from the measurements of the transient response of the device. The tapered optical fiber sensor was fabricated using a single-mode opt...

An optical tilt sensor was developed and its performance was investigated. The tilt sensor set-up consisted of a laser light source, lenses and an image sensor. A precision reference tilt sensor was also installed on the same stage, and the measurement results of tilt angles using the optical and reference tilt sensors were correlated. The correlation coefficient (R-value) obtained under ideal ...

UV sensors are typically very sensitive to aging and solarization effects of the harsh environment in which they are used. Minimizing the long term effects of UV on a sensor/optics is extremely challenging, especially with on-line installed sensors used for continuous monitoring on a 24/7 basis. This paper describes a patented method of reducing the effects of aging and solarization to a minima...

We propose and demonstrate an optical voltage sensing scheme based on a macrobending optical fiber in a ratiometric power measurement system. This novel approach to sensing has not been utilized before and has the advantage that the sensor involves simple fabrication compared to existing fiberoptic voltage sensors. To prove the feasibility of such a fiber-optic sensor, a sensor for a voltage ra...