detection of hazardous materials
Optical fibers are an important area of study for remote chemical sensing applications. Current designs rely on employing optical fibers for collecting and transmitting an emissive signal at one end of the fiber to an optical detector at the other. Inherent to this approach are several limitations. First, both the remoteness and sensitivity of detection are restricted by the fiber’s numerical aperture (NA), its transmission and bending losses, and the sensitivity of the detector. While NA can be increased with hollow core photonic bandgap fibers and highly sensitive photodetectors can be implemented, the detection system is nonetheless limited so long as the fiber is used for waveguiding. Second, since light emitted only at the end facet, distributed sensing over large areas is inefficient.
The invention is an alternative materials system and approach for remote luminescence-based chemical detection that is inherently adaptable for distributed sensing. In this system, the photodetector is embedded along the entire fiber length. The approach maximizes signal collection efficiency, while eliminating the need to propagate the optical signal along the fiber to a distal external detector. By optimizing the fiber materials architecture for chemical sensing and reducing the noise equivalent power by nearly two orders of magnitude compared to previous work, trace-level detection limits of peroxide vapor down to 10 parts per billion (ppb) was achieved. This is on par with current state-of-the-art hydrogen peroxide vapor sensors, which have been developed only for on-the-spot non-remote detection. The small footprint, potential for multiplexing, flexible form factor, scalable manufacturing, and compatibility with miniaturized electronics of the fiber architectures demonstrated here enable remote and distributed sensing schemes to meet current societal needs.
detection of peroxide vapor down to 10 parts per billion
architecture guarantees small footprint, high potential for multiplexing,
flexible form factor, scalable manufacturing and excellent compatibility with