The invention discloses a
system and a method for monitoring gas
pollution based on the passive long-path
differential absorption spectrum technology. The
system adopts the technical scheme that a receiving
telescope is arranged; a
diffuse reflection board A is installed right ahead the receiving
telescope; a
diffuse reflection board B is installed between the receiving
telescope and the
diffuse reflection board A; the diffuse reflection boards A and B are parallel; and a rotating shaft is connected with the lower end of a baseplate of the diffuse reflection board B. A control motor rotates, and the diffuse reflection board B is
cut in and
cut out of a receiving
optical path of the receiving telescope; the
sunlight which is reflected by the diffuse reflection boards A and B is collected by the receiving telescope, and is transmitted to a
spectrometer through optical fibers respectively;
scattered light entering the
spectrometer is subjected to chromatic dispersion,
photoelectric conversion and
digitization, transferred to a computer through an
USB cable for storage; and the concentration of the
pollution gas can be analyzed and calculated through utilizing the
differential absorption spectrum method. Through the combination of the advantages of the conventional active and passive
differential absorption spectrum technologies, the
system structure is simple, and the deficiencies that in the system for monitoring gas
pollution based on the active long-path differential absorption spectrum technology of the prior art, the
artificial light source has short service life and high
power consumption and the angle reflecting mirror is difficult to install are overcome.