Time-multiplexing is a method to increase the brilliance of diode lasers, i.e. a sequence of laser pulses emitted from different laser diodes at different times is guided onto a common optical path via a cascade of polarizing cube beam splitters and polarization switches. The latter are made of piezo-electric crystals oscillating in resonance and making use of the photo-elastic effect to obtain the desired modulation of polarization. We realized a demonstrator for time multiplexing of four laser diodes with such self-excited photo-elastic modulators. The latter is a new alternative to conventional photo-elastic modulators used in ellipsometers.

No abstract

We demonstrate high-frequency Q-switching of a fiber rod laser with a Single-Crystal Photo-Elastic Modulator (SCPEM) made of a LiTaO₃₋ crystal. This type of photo-elastic modulator can be driven simultaneously with two different eigenmodes to achieve a shorter rise time, which is essential for high-power operation. When operated in the laser cavity, a pulse repetition frequency of 183.6 kHz with an average power of 47 W, a pulse duration of 26 ns, and a peak power of 10.5 kW was achieved.

We developed a small and compact system of diode lasers, which can be inserted into the lower tools of a bending press. The parts of the system allow easy plug and play operation and can be installed for any bending length. The diode laser, which is based on 200 W laser bars on microchannel cooler, allows the heating of sheet metals in the forming zone shortly before and during the bending process. There is no unnecessary heating of other parts of the bending equipment, no wear of the tool, and, if properly done, no damage of the surface of the metal. The power per bending length is 16 kW/m.

No abstract