Single-pixel imaging technology could cut cost of methane release detection

Image: JWN

A U.K. research partnership has produced a technology that could significantly reduce the cost of methane detection at a time when oil and gas companies are facing mandated methane emissions reductions targets.

The technology uses a technique called single-pixel imaging to create real-time video images of methane gas in a typical atmospheric setting. Single-pixel imaging uses just one light-sensitive pixel to build digital images instead of using conventional multi-pixel sensor arrays, which can be prohibitively expensive for infrared imaging.

Current systems to visualise methane gas, a potent greenhouse gas, are typically expensive, bulky and power-hungry. The new technology allows the researchers to build a much smaller, cheaper gas detection system.

It was developed by researchers from the University of Glasgow’s School of Physics and Astronomy and Scottish photonics company M Squared Lasers. It is described in a paper published in the journal Optics Express.

The scene in front of the sensor is illuminated using a sequence of infrared patterns created using a laser tuned to 1.65μm, the absorption wavelength of methane, and display technology commonly found in digital data projectors.

Using sophisticated sampling techniques to correlate the projected patterns and the gas, the researchers can create a real-time, coloured coded, image of the gas overlaid on an image of the scene using a conventional colour camera, they describe in a press release.

“Our detector allows us to produce images which refresh 25 times a second, equivalent to the standard frame rate of video, which provides a highly accurate real-time picture of the scene in front of the detector,” said Graham Gibson, lead author of the paper. “M Squared’s advanced laser systems allowed us to effectively ‘tune in’ to the wavelength of methane gas, and opens up the possibility of using the system to detect other types of gases in the future.”

The collaboration between the University of Glasgow and M Squared Lasers was facilitated by QuantIC, the U.K.’s quantum imaging technology hub, which is based at the University.

Canada, the U.S. and Mexico agreed in 2016 to cut methane emissions 40-45 per cent by 2025, though the U.S. has recently indicated it may pull out of the trilateral deal. The global gas sensing market was estimated at $1.78 billion in 2013 and is expected to be worth $2.32 billion by 2018, offering an attractive opportunity for new technology.