Open AccessThe introduction of laser remote sensing systems carries a particular risk to the human’s sense of vision. A structure of the eye, and especially the retina, is the main critical organ as related to the laser radiation.
The work uses the optical models of the atmosphere, correctly working in both the UV and the near-IR band, to select the eye-safe radiation wavelengths in the UV (0.355 m) and near-IR (~ 1.54 and ~ 2 m) spectral bands from the point of view of recorded lidar signal value to fulfill the tasks of laser sensing the natural formations and laser aerosol sensing in the atmosphere.
It is shown that the remote sensing lasers with appropriate characteristics can be selected both in the UV band (at a wavelength of 0.355 μm) and in the near-IR band (at wavelengths of 1.54 ~ or ~ 2 μm).
Molecular scattering has its maximum (for the selected wavelength) at a wavelength of 0.355 μm in the UV band, and the minimum at the wavelengths of 1.54 and 2.09 μm in the near -IR band. The main contribution to the molecular absorption at a wavelength of 0.355 μm is made by ozone. In the near-IR spectral band the radiation is absorbed due to water vapor and carbon dioxide.
Calculations show that the total effect of the molecular absorption and scattering has no influence on radiation transmission for both the wavelength of 0.355 μm in the UV band, and the wavelengths of 1.54 and 2.09 μm in the near-IR band for sensing trails ~ 1 km.
One of the main factors of laser radiation attenuation in the Earth's atmosphere is radiation scattering by aerosol particles.
The results of calculations at wavelengths of 0.355 μm, 1.54 μm and 2.09 μm for the several models of the atmosphere show that a choice of the most effective (in terms of the recorded signal of lidar) and eye-safe radiation wavelength depends strongly on the task of sensing.
To fulfill the task of laser sensing the natural formations, among the eye-safe wavelengths there is one significantly advantageous, i.e. the wavelength of 1.54 μm in the near-IR band. However, as to the problem of aerosol sensing in the atmosphere, the wavelength of 1.54 μm in the near-IR region has no a distinct advantage over the wavelength of 0.355 μm in the UV band.