Modulation of diode laser radiation for the formation of a distance-independent backscattered signal

We propose a probing regime, in which the backscattered signal energy is independent of the distance from the surface of a scattering object. This regime is implemented using a part of the laser radiation power. With respect to the efficiency of using the laser during one measurement, the proposed regime is close to the pseudorandom noise continuous wave lidar regime. Using diode lasers, the regime of the degenerate energy response function and the lidar regime can be implemented in a single device. The relations between the geometric parameters of the probing scheme and the modulation parameters of laser radiation are obtained. The dependence of the linearity range of the diode laser on the relation between the length of the receiving channel near-field zone and the length of the probed trace is substantiated.