Long-range distributed optical fiber sensors1-5 exploit the interaction between laser light and the fundamental energy transport mechanisms in the scattering medium. Here we report on the use of Brillouin loss for a combined distributed temperature and strain sensor. Brillouin lossbased distributed sensors exploit the Brillouin interaction between pulsed and cw optical beams counterpropagating ...

Up-to-date fibre lasers produce multi-kw radiation with an excellent beam quality. Compared to CO2-lasers, fibre lasers have relatively low operational costs and offer a very high flexibility in production due to the beam delivery with process fibres. As a consequence, fibre lasers have attracted more and more attention. On the other hand, their use in industrial applications especially in the ...

A compact UV pulsed laser pumped by high-power two-dimensional arrays of vertical-cavity surface-emitting lasers (VCSELs) was presented. A passively Q-switched 1064-nm Nd:YAG laser was side-pumped by kW-class 808-nm VCSEL pump modules and the output pulses were frequency quadrupled to 266-nm. 10-ns, 0.68-mJ UV pulsed output was obtained at 1.33k-Hz repetition rate. The average UV power is > 0.9...

The use of shielding gases in laser beam welding is particular interest for materials interacting with ambient oxygen, e.g., copper, titanium or high-alloy steels. These are often processed by remote where short welds (e.g., up to 40 mm seam length) commonly used. Such setups prevent gas nozzles from being carried along on the optics due scanner application and a small area needs be served loca...

In this paper altitude measurement from water surface using laser beam is presented. Research data indicate that the reflection of infrared waves from water surface is about zero and it is less than 2% for visible radiations. Phase-shift and heterodyne technique was used for the measurement, and the laser beam ( mW p nm 10 , 700 = = l ) was modulated by a sine wave having a fixed frequency....

Magnusson, M. 2006. Evaluation of remote sensing techniques for estimation of forest variables at stand level. Doctor's dissertation. There is a continuous need for accurate forest description. Forest data at stand level is required in forestry planning, in particular when scheduling treatments within the next few years. Collection of forest data is typically acquired with subjective surveying ...

Remote sensing technologies such as SoDAR and LiDAR have proved to be cost-effective methods of acquiring critical project datasets from locations that present access challenges. As a result they are increasingly being adopted in the offshore environment where their compact, portable and robust characteristics can be maximally leveraged to acquire data that previously would have represented gre...

in this work, laser bending of perforated sheets has been investigated numerically. laser bending of perforated sheets is more complicated than non-perforated sheets due to their complex geometries. in this paper, laser bending of perforated sheets is studied numerically in the form of thermo-mechanical analysis with abaqus/implicit code. for this purpose, the effects of process and sheet param...

The invention of the laser in 1960 has been a very important milestone for our presentday society. This remarkable new light source not only triggered a revolution in science and technology but also gave rise to a significant improvement of the quality of our daily life. An important type of laser is the so-called Raman laser, the lasing mechanism of which is based on Stimulated Stokes Raman Sc...