Abstract: A method and arrangement for compensation of thermally induced depolarising effects in an optical resonator employ a retroreflective prism effecting multiple instances of total internal reflection as one end mirror of the resonator. The retroreflective prism has a first roof edge face pair made of two perpendicular roof edge faces and at least one second face with total internal reflection or a second roof edge face pair. Laser radiation entering parallel to the optical axis of the resonator undergoes total internal reflection through an angle ? at the second face or the second roof edge face pair before it undergoes total internal reflection at the first roof edge face pair and emerges again from the retroreflective prism in a manner parallel to the optical axis of the resonator following another instance of total internal reflection at the second face or the second roof edge face pair.

Abstract: Examples include a network node for a non-detectable laser communication system, a bi-directional laser communication system comprising such a network node, a method for a non-detectable laser communication, and in particular to an optronic system for non-detectable, compact bi-directional laser communication, which is particularly suitable for communication with a drone or other unmanned vehicle (UXV).

Abstract: A fibre laser assembly includes a pump laser assembly for optical pumping of an active fibre with first pump radiation of a first pump wavelength and means for the generation of second pump radiation at a second pump wavelength, which lies between the first pump wavelength and the wavelength of the seed laser. Doping concentration, length of the active fibre, and power of the first pump radiation are coordinated such that the active fibre absorbs the first pump radiation in the first fibre portion to >90%, the radiation of the second pump wavelength in the first fibre portion is amplified by the first pump radiation to generate the second pump radiation, and the laser radiation of the seed laser is amplified in the remaining second fibre portion by the second pump radiation.

Abstract: An optronic system (100) for a countermeasure unit (10) to optically communicate with another communication terminal is disclosed. The countermeasure unit (10) comprises a laser beam source (12) and a directing device (14) for a laser beam (15) of the laser beam source (12) and is configured to dazzle or to jam an object of threat (50). The optronic system (100) comprising: a detector (110), a modulation unit (120), and a control unit (130). The detector (110) is configured to detect an incoming communication in an incoming signal (25). The modulation unit (120) is configured to demodulate the incoming signal (25) or cause a modulation of an outgoing laser beam (15). The control unit (130) is configured, in response to the detected incoming communication, to control the modulation unit (120) to demodulate the incoming signal (25) or to modulate the outgoing laser beam (15) to enable an optical communication via the laser beam source (12) of the countermeasure unit (10).

Abstract: An optronic system (100) for a countermeasure unit (10) to optically communicate with another communication terminal is disclosed. The countermeasure unit (10) comprises a laser beam source (12) and a directing device (14) for a laser beam (15) of the laser beam source (12) and is configured to dazzle or to jam an object of threat (50). The optronic system (100) comprising: a detector (110), a modulation unit (120), and a control unit (130). The detector (110) is configured to detect an incoming communication in an incoming signal (25). The modulation unit (120) is configured to demodulate the incoming signal (25) or cause a modulation of an outgoing laser beam (15). The control unit (130) is configured, in response to the detected incoming communication, to control the modulation unit (120) to demodulate the incoming signal (25) or to modulate the outgoing laser beam (15) to enable an optical communication via the laser beam source (12) of the countermeasure unit (10).

Abstract: The present invention especially concerns the field of lasers. Specifically, the object of the invention is a process for the emission of pulsed laser radiation generated by at least one laser crystal which is located in a cavity containing a first and a second mirror and pumped by des pumping means, wherein said process includes a first stage which consists of generating a first pumping laser radiation with an intensity of Jc which is capable of bringing the crystal at least to the laser emission threshold and a second stage which consists of generating a second pumping laser radiation with an intensity of Jp in the form of a step, whereby said second radiation is superimposed, at least in part, on said first radiation or immediately succeeds it, and whereby the intensity Jp, in the latter case, is greater than the intensity Jc of said first radiation, as well as a laser source capable of activating said process.

Abstract: The present invention relates in particular to the field of lasers and in particular to a laser source having a neodymium-doped crystal (2; 23) or fiber and pumpable by pumping means (3; 25) and a non-linear Raman effect converter stimulated in methane (4; 32), characterized in that the crystal (2; 23) or fiber pumped by said pumping means (3; 25) is able to emit a laser radiation at a wavelength between 1.31 and 1.36 ?m and in that the Raman converter (4; 32) is able to convert the radiation generated by the crystal (2; 23) or by the fiber into at least one second radiation (7; 36) with a wavelength between 2 and 2.3 ?m.

Abstract: The present invention especially concerns the field of lasers. Specifically, the object of the invention is a process for the emission of pulsed laser radiation generated by at least one laser crystal which is located in a cavity containing a first and a second mirror and pumped by des pumping means, wherein said process includes a first stage which consists of generating a first pumping laser radiation with an intensity of Jc which is capable of bringing the crystal at least to the laser emission threshold and a second stage which consists of generating a second pumping laser radiation with an intensity of Jp in the form of a step, whereby said second radiation is superimposed, at least in part, on said first radiation or immediately succeeds it, and whereby the intensity Jp, in the latter case, is greater than the intensity Jc of said first radiation, as well as a laser source capable of activating said process.

Abstract: The present invention relates in particular to the field of lasers and in particular to a laser source having a neodymium-doped crystal (2;23) or fiber and pumpable by pumping means (3; 25) and a non-linear Raman effect converter stimulated in methane (4; 32), characterized in that the crystal (2; 23) or fiber pumped by said pumping means (3; 25) is able to emit a laser radiation at a wavelength between 1.31 and 1.36 ?m and in that the Raman converter (4; 32) is able to convert the radiation generated by the crystal (2; 23) or by the fiber into at least one second radiation (7; 36) with a wavelength between 2 and 2.3 ?m.