Technology of interference becomes more advancing. Adopting fog and aerosols is the best way to interfere optical
detection. Due to the fog and aerosols, target recognition becomes difficult under this environment. In the present paper a
method is given to solve this problem in a simple way.
A dual-wavelength technology used in anti-interfere for long range and short distance detection is introduced in this
paper, which can discriminate the backscattering reflection of fog and aerosols. In the present work the scattering
character of the special fog and aerosols environment is calculated using the Rayleigh scattering method and Mie
scattering method. The scattering characters in different environment are analyses using two wavelengths, i.e. one
wavelength lies in ultraviolet wave band, the other in near infrared wave band. The results indicated that the ratio of
proportion-discrimination is usually greater than 2, and deeper the strength of the fog and aerosols, the greater the ratio.
This method also validated by experiment. In the present study, three kinds of wavelength such as 405nm, 670nm and
808nm are adopted. The intensity data collected shows that the ratio is greater than 3.
The performance and working principle of the system and its components are analyzed in details. Based on the full
system, the dual-wavelength technology can be well applied. The result of the experiments also proves that the
technology is efficient, especially in the heavy fog and aerosols environment.
The dual wavelength method can be used for long range and short distance detection.