Burst shaping in a fiber-amplifier chain seeded by a gain-switched laser diode.

A low-power source, such as a gain-switched laser diode, usually requires several amplification stages to reach sufficient power levels. When operating in burst mode, a correct input burst shape must be determined in order to compensate for gain saturation of all amplifier stages. In this paper we report on closed-form equations that enable saturation compensation in multiamplifier setups, which eliminates the need for an adaptive feedback loop.

Short pulsed gain-switched fiber laser with improved efficiency utilizing unabsorbed pump recovery.

A simple solution for increasing the slope efficiency of a gain-switched fiber laser based on Yb-doped active fiber is presented. By adding a fiber amplifier stage, which recovers the unabsorbed pump light from the gain-switched oscillator, a significant increase in slope efficiency is achieved. The pulses at 1030-nm wavelength have an FWHM of 28 ns and a peak power of 2.

Dynamic symmetrical pattern projection based laser triangulation sensor for precise surface position measurement of various material types.

This paper describes a custom, material-type-independent laser-triangulation-based measurement system that utilizes a high-quality ultraviolet laser beam. Laser structuring applications demand material surface alignment regarding the laser focus position, where fabrication conditions are optimal. Robust alignment of various material types was solved by introducing dynamic symmetrical pattern projection, and a "double curve fitting" centroid detection algorithm with subsurface scattering compensation.

Power scaling of AOM-switched lasers with SCPEM-based time-multiplexing.

Power Scaling of a Q-switched laser designed for internal frequency conversion is demonstrated by combining two Nd:YVO4-gain-channels with a time-multiplexing scheme based on a single crystal photo elastic modulator (SCPEM). Both channels are coupled with a polarizer and share an output-coupler and acousto-optic modulator (AOM). In order to combine two channels by time multiplexing, the single crystal photo elastic modulator is used which switches between two channels, while the acousto-optic modulator conducts the Q-switching.