Dual transmitter for optical testing links with optimized beam shape

The article deals with optical testing links. These links are used to measure the optical properties of the atmosphere during various environmental events, e.g. fog, rain, haze. The measurement is often carried out using two different wavelengths. Such testing links are then called dual optical testing link. It can be further possible to determine limits of usability of different wavelength to ensure reliable function of optical data link. Modern optical testing links deal with many problems that decrease their usability or even question the results. To avoid such problems, new concept of dual optical testing link transmitter is proposed. It uses 850 nm and 1550 nm wavelengths. Considering relatively large spectral distance of the wavelengths, one can decide on usability of far- or near-IR source for different weather conditions. The proposed concept also concerns optical intensity distribution of transmitted beam by obtaining multimode distribution. Such optical intensity distribution significantly reduces power fluctuations in the plane of the receiver aperture in case of atmospheric turbulences along the path.