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In order to improve the reliability of micro-spot welding of metal parts in production such as e.g. in electron guns for TV picture tubes, real-time information about the evolution of the welding process should be available to allow on-line modification of ...
Among all non-linear optical effects observed in single-mode optical fibres, stimulated Brillouin scattering (SBS) is of particular importance since it has numerous practical implications. SBS occurs when laser waves are scattered through the interaction o ...
The application of lasers in microsurgery and in particular in neurosurgery offers many advantages such as, e.g., hemostasis, no-touch (i.e. aseptic) procedures, and pinpoint accuracy. However, these advantages can often not be fully exploited since adequa ...
We present the design of a highly efficient, pulsed ammonia laser which is optically pumped by a commercial TEA CO2 laser and is line tunable in the spectral range of 780-930 cm(-1). The power, spectral, and temporal characteristics of the laser have been ...
Microgun-pumped blue lasers with lasing thresholds in the 4-20 kW/cm(2) range for temperatures between 83 and 225 K were fabricated by molecular beam epitaxy. The devices exploit graded index, separate confinement Zn1-xCdxSe/ZnSe heterostructures and use a ...
We present a monolithically integrated vertical coupled cavity surface-emitting laser diode which exhibits stable laser emission at two design wavelengths simultaneously. The device consists of two slightly asymmetric coupled vertical cavities containing s ...
The common configuration for deflecting laser beams in two dimensions is based on two single-axis galvanometric scanners placed perpendicular to each other. Over recent years, these fast scanners have proved to be both very reliable and very accurate. They ...
Frequency doubled Nd:YAG lasers represent an attractive alternative to other laser tools for many material processing applications, but frequency doubling with pulsed Nd:YAG lasers has been performed until now only with pulses of tens of nanoseconds. In ma ...
Intersatellite optical communication links require laser beams of at least 1 W of power modulated at gigahertz frequencies. They can be delivered by a master oscillator power amplifier system which consists of a stable single-frequency Nd:YAG laser, a high ...
Fabrication and characterization of a current-injected InGaAs-GaAs quantum-wire gain-coupled distributed feedback (DFB) laser operating at 77 K at a wavelength of 923 nm are presented, Threshold current densities in broad area lasers were measured to be as ...
