Methane detection using an interband-cascade LED coupled to a hollow-core fiber

Abstract

Midwave infrared interband-cascade light-emitting devices (ICLEDs) have the potential to improve the selectivity, stability, and sensitivity of low-cost gas sensors. We demonstrate a broadband direct absorption CH4 sensor with an ICLED coupled to a plastic hollow-core fiber (1 m length, 1500 µm inner diameter). The sensor achieves a 1σ noise equivalent absorption of approximately 0.2 ppmv CH4 at 1 Hz, while operating at a low drive power of 0.5 mW. A low-cost sub-ppmv CH4 sensor would make monitoring emissions more affordable and more accessible for many relevant industries, such as the petroleum, agriculture, and waste industries.

p‐InAsSbP/n‐InAs Double Heterostructure as an On‐Chip Midinfrared Evanescent Wave Sensor of Liquids

“…Unlike many optopairs including those in refs. [1‐8,12,13,15,18,24‐27] the LED and PD in our on‐chip sensor were not fully electrically independent as mesa p‐n junctions had common n‐type area (substrate). At this stage our set‐up provided no possibility using a pulse operation mode for the “illuminated” I – V measurements while such measurements could potentially increase the SNR by using higher LED current.…”

“…A 3 B 5 based mid‐IR light‐emitting diodes (LEDs) and photodiodes (PDs) are important optoelectronic components for portable and inexpensive photoacoustic, [ 1–3 ] spectroscopic/multichannel [ 4 ] and nondispersive infrared (NDIR) [ 3–8 ] analyzers of such gases as CO 2 , CO, CH 4 , and C 2 H 5 OH vapor. The small size and low power consumption of the aforementioned components are also attractive for the evanescent wave sensing/attenuated total reflection (ATR) measurements of liquids, solids, and gases.…”

Resonant cavity infrared detectors for scalable gas sensing

“…Precise and accurate measurements must also account for changes in ambient pressure, temperature, and humidity, [16][17][18][19] as illustrated in Fig. 4 for the case of temperature.…”

Optical Fiber‐Based Gas Sensing for Early Warning of Thermal Runaway in Lithium‐Ion Batteries

“…The most challenging one is the cost of optical fiber technologies, in addition to gas sensing head, the costly laser source, photodetectors, and even spectrometer are required as well. Even though cheap hardware is under developing and some hardware has already achieved low cost, [ 151,152 ] it is still a long wait to expect technological advances to bring newer and cheaper hardware. In contrast, multiplex or distributed sensing technologies [ 134,153 ] are currently the most valuable solution, which also demonstrate the advantage of the optical sensing over the electrical sensing technology.…”