Method for remote detection of gaseous substances in the atmosphere by the DIAL system with two lasers and a remote detector

A remote detector of gaseous substances in an atmosphere by a differential absorption LIDAR (DIAL) system, the remote detector comprising:

• a first laser of the DIAL system;
• a second laser of the DIAL system;
• a semipermeable mirror of the DIAL system positioned at an intersection of axes of laser beams from the first laser and the second laser;
• a reflecting mirror of the DIAL system positioned behind the semipermeable mirror and located in a forward direction of a laser beam advance generated by the second laser and also in a reflected direction from the semipermeable mirror of the laser beam advance generated by the first laser;
• a first aperture of the DIAL system located in a forward direction from the semipermeable mirror such that 50% of the laser beam advance from the first laser passes through the semipermeable mirror and impinges on the reflecting mirror and 50% of the laser beam advance from the second laser is reflected;
• and
• a second aperture of the DIAL system located in the reflected direction from the reflecting mirror such that 50% of the laser beam advance from the first laser and 50% of the laser beam advance from the second laser are reflected and the first aperture and the second aperture are positioned to remotely detect the gaseous substances in the atmosphere.