Multi-laser gas leakage detector

A method for remotely detecting gas leakage from a pipeline comprising:

• emitting, from a first light source, a first outgoing light beam having a first wavelength in a mid-infrared (IR) range and a second outgoing light beam having a second wavelength in the mid-IR range;
• modulating the first outgoing light beam with a first modulation signal to generate a first modulated outgoing light beam, the first modulation signal having a first frequency;
• modulating the second outgoing light beam with a second modulation signal to generate a second modulated outgoing light beam, the second modulation signal having a second frequency different from the first frequency, the first modulated outgoing light beam and the second modulated outgoing light beam traversing towards a region of the pipeline;
• collecting, at a first light detector, a first incoming light beam having the first wavelength and a second incoming light beam having the second wavelength, the first incoming light beam being the first modulated outgoing light beam reflected off of an outer surface of the region and the second incoming light beam being the second modulated outgoing light beam reflected off of the outer surface of the region;
• comparing an intensity of the first incoming light beam to an intensity of the first outgoing beam to calculate a first absorption rate;
• comparing an intensity of the second incoming light beam to an intensity of the second outgoing beam to calculate a second absorption rate;
• responsive to determining the first absorption rate above a first threshold and the second absorption rate above a second threshold, determining that the region has a leakage of a first gas and the second gas;
• and
• triggering an image generator to capture an image of the region of the pipeline in response to determining that the region has the leakage of the first gas and the second gas.