A laser-desorption mass spectrometer will be part of the ESA-led ExoMars mission with the objective of identifying organic molecules on planet Mars. A UV laser source emitting nanosecond pulses with pulse energy of about 250 μJ at a wavelength of 266 nm is required for the ionization of nonvolatile soil constituents. A passively q-switched, diode-pumped Nd∶YAG laser oscillator with external frequency quadrupling has been developed. The basic optical concept and a previously developed flight-near prototype are redesigned for the engineering qualification model of the laser, mainly due to requirements updated during the development process and necessary system adaptations. Performance issues like pulse energy stability, pulse energy adjustment, and burst mode operation are presented in this paper.
A prototype of a compact light-weight passively Q-switched diode pumped Nd:YLF solid-state laser system for harsh environments has been developed. It emits 2ns pulses at a wavelength of 1053nm with a repetition rate of up to 50Hz and an energy of 1.5mJ. The beam propagation factor M2-has a value of 1.2. The total mass of the prototype electronics, consisting of an electronic board including pump diodes and thermal control to be accommodated with other electronics in a shared electronics box, and the complete solid-state laser head is 189g with further potential for mass reduction with respect to a flight model development. Applications of this laser system are amongst others laser-induced breakdown spectroscopy (LIBS) for planetary surface exploration or short range altimetry.
A near-flight prototype of a pulsed UV laser has been developed for the Mars Organic Molecule Analyzer (MOMA) of the ExoMars mission. The laser head is based on a Nd:YAG oscillator with subsequent frequency quadrupling and emits nanosecond pulses with an energy of > 300 μJ at a wavelength of 266 nm. The design is compact and lightweight. Tests in relevant environment regarding temperature, vibration, and radiation have been performed.
Q-switched lasers systems with ns pulse duration and energies ranging from 1 to more than 100mJ are utilized for many spaceborne applications such as altimetry of planets and moons. Furthermore, Q-switched lasers can be used for distance measurements during docking and landing manoeuvres. To keep the diameter of the beam small over a large distance and to consequently achieve a good lateral resolution, a good beam propagation factor M² is required. Moreover, Q-switched lasers can be used directly on the planetary surface for exploration by laser-induced breakdown spectroscopy or laser desorption mass spectrometry.
Planetary exploration constitutes one of the main components in the European Space activities. Missions to Mars, Moon and asteroids are foreseen where it is assumed that the human missions shall be preceded by robotic exploitation flights. The 3D vision is recognised as a key enabling technology in the relative proximity navigation of the space crafts, where imaging LiDAR is one of the best candidates for such 3D vision sensor.
The femto-second technology gains of increasing importance in industrial applications. In this
context, a new generation of compact and low cost laser sources has to be provided on a commercial
basis. Typical pulse durations of these sources are specified in the range from a few hundred femtoup
to some pico-seconds, and typical wavelengths are centered around 1030-1080nm. As a
consequence, also the demands imposed on high power optical components for these laser sources
are rapidly increasing, especially in respect to their power handling capability in the ultra-short pulse
range. The present contribution is dedicated to some aspects for improving this quality parameter of
optical coatings. The study is based on a set of hafnia and silica mixtures with different compositions
and optical band gaps. This material combination displays under ultra-short pulse laser irradiation
effects, which are typically for thermal processes. For instance, melting had been observed in the
morphology of damaged sides. In this context, models for a prediction of the laser damage
thresholds and scaling laws are scrutinized, and have been modified calculating the energy of the
electron ensemble. Furthermore, a simple first order approach for the calculation of the temperature
was included.
This paper presents the theoretical results from semi-analytical and numerical simulations of the THz generation in a two-dimensional geometry in a periodically poled material. The Green's function of a propagating line source is utilized to calculate the field radiated into a homogeneous material and generated by a nonlinear polarization which is confined in one transverse direction. A numerical (FDTD) method is taken for the investigation of the radiation from a material-to-air interface parallel to the direction of propagation of the optical wave. The angular dependence of the radiated transverse electric and magnetic fields is shown and explained for different ratios between the optical pulse width and the walk-off time of optical and THz waves. The numerical results are calculated for lithium niobate, a material known for its good suitability for periodical domain inversion.
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