Peter Baues

The Basic Fault-tolerant System

Designed for network applications, this system achieves fault tolerance by exploiting redundancies inherent in standard components.

A concept for the generation of reproducible and controllable giant pulses

A YAG: Nd laser system is described which supplies giant pulses which are within 3% constant in shape and size and do not depend on the pump energy and the shape of the pumping pulses. A LiNbO3 crystal cut at the Brewster angle is used as a Q switch. Since the oscillation of the laser in the off state is used to open the Q switch, a definite inversion always occurs within the laser rod at the instant the switch opens that is due to the threshold of the off state and depends solely on the cavity characteristics. The height of the giant pulses is moreover easily controlled by varying the voltage applied to the LiNbO3 crystal.

Generation of reproducible giant pulses with an optically regenerative Q switch

In a new concept for an optically regenerative Q switch which is described, the oscillation of the laser with the cavity closed is sensed by a fast photodiode whose output signal opens the electro‐optical Q switch. The threshold of the laser as a function of the modulator voltage is theoretically investigated; the empirical results obtained with a YAG:Nd3+ laser agree well with theory. The advantages offered by the optically regenerative Q switch are the easy controllability of the peak power of the giant pulses by way of the modulator voltage and the excellent reproducibility of the giant pulses. The experiments revealed the variations between pulses to be less than 3%. Thus the optically regenerative Q switch is practical for all giant‐pulse lasers whose emission is required to be highly stable.