A laser device for laser detection and ranging (LiDAR), comprising: - a laser oscillator configured for emitting a pulsed laser beam (B4) when optically pumped at a pumping wavelength, the laser oscillator being configured for emitting the laser beam (B4) at a laser wavelength in a laser direction (X1) along a laser beam path, - a laser beam amplifier disposed on the laser beam path and configured to amplify the laser beam (B4) when the laser beam amplifier is optically pumped at the pumping wavelength, - a pumping unit disposed between the laser oscillator and the laser beam amplifier and configured to, when receiving an incoming continuous pumping beam having the pumping wavelength, * transmit the laser beam (B4) along the laser direction ; * send the pumping beam for pumping the laser oscillator in the opposite direction (X2) to the laser direction, and * transmit a part of the pumping beam which is reflected by the laser oscillator for pumping the laser beam amplifier , in the laser direction, such that the laser beam, the pumping beam and the part of the pumping beam which is reflected by the laser oscillator are collinear along the laser beam path, wherein the pumping unit is further configured in order that the pumping beam (B2) which is sent for pumping the laser oscillator is circularly polarized. - a laser oscillator configured for emitting a pulsed laser beam (B4) when optically pumped at a pumping wavelength, the laser oscillator being configured for emitting the laser beam (B4) at a laser wavelength in a laser direction (X1) along a laser beam path, - a laser beam amplifier disposed on the laser beam path and configured to amplify the laser beam (B4) when the laser beam amplifier is optically pumped at the pumping wavelength, - a pumping unit disposed between the laser oscillator and the laser beam amplifier and configured to, when receiving an incoming continuous pumping beam having the pumping wavelength, * transmit the laser beam (B4) along the laser direction ; * send the pumping beam for pumping the laser oscillator in the opposite direction (X2) to the laser direction, and * transmit a part of the pumping beam which is reflected by the laser oscillator for pumping the laser beam amplifier , in the laser direction, such that the laser beam, the pumping beam and the part of the pumping beam which is reflected by the laser oscillator are collinear along the laser beam path, wherein the pumping unit is further configured in order that the pumping beam (B2) which is sent for pumping the laser oscillator is circularly polarized. * transmit the laser beam (B4) along the laser direction ; * send the pumping beam for pumping the laser oscillator in the opposite direction (X2) to the laser direction, and * transmit a part of the pumping beam which is reflected by the laser oscillator for pumping the laser beam amplifier , in the laser direction, such that the laser beam, the pumping beam and the part of the pumping beam which is reflected by the laser oscillator are collinear along the laser beam path, wherein the pumping unit is further configured in order that the pumping beam (B2) which is sent for pumping the laser oscillator is circularly polarized. <EOS>