This research developed new methods for high-performance control of laser beams in high energy laser weapons and laser communications. These methods achieve optical wavefront correction, laser beam pointing and target tracking with precision levels significantly beyond those achievable by existing methods for beam control, thereby increasing the bandwidths and target distances for which beam co...

BACKGROUND Ion beam has been used in cancer treatment, and has a unique preferable feature to deposit its main energy inside a human body so that cancer cell could be killed by the ion beam. However, conventional ion accelerator tends to be huge in its size and its cost. In this paper a future intense-laser ion accelerator is proposed to make the ion accelerator compact. SUBJECTS AND METHODS ...

The mean lifetime w of the 4p' 'F7/2 level of Ar II has been measured using a variant of the collinear laser-beam —fast-ion-beam spectroscopy technique. Our variant requires no mechanical motion or laser frequency tuning. The result is ~=8.414+0.025 ns in agreement with an earlier, comparably precise, measurement based on a crossed laser —ion-beam technique. The result lies above all theoretica...

2014 New efficient non-optical detection methods of optical resonances in colinear laser spectroscopy are described. A first method uses the field ionization of a Rydberg state populated by means of two lasers : one is single frequency and interacts colinearly with the fast atomic beam, the other one is multimode and interacts perpendicularly. By detecting, at resonance, the produced ions inste...

Laser beam welding is becoming widely used in many industrial applications. This paper reviews recent research conducted on the performance, potential and problems of thick section butt joint laser welding. Common defects that occur in laser beam welding with high power laser welding are discussed and possible solutions proposed. Methods of welding process efficiency improvement are analyzed.

Fraunhofer Institute for Laser Technology had developed the SHADOW welding technique, in which high speed joining with minimal distortion is possible using a pulsed Nd:YAG laser. The possibility of high speed, high quality welding had been also reported by use of a single-mode fiber laser. The combination of micro-beam and high speed laser scanning offers potential advantages for thin metal she...

Laser-based missile-defence systems are being increasingly employed on aircraft to provide protection when attacked by optically-guided weapons. In some engagements the laser beam must pass through the exhaust gases of the aircraft. To predict the increase in laser beam divergence and jitter of the laser beam direction, an understanding of the exhaust gas structure and its influence is required...

A new mechanism is reported that increases electron energy gain from a laser beam of ultrarelativistic intensity in underdense plasma. The increase occurs when the laser produces an ion channel that confines accelerated electrons. The frequency of electron oscillations across the channel is strongly modulated by the laser beam, which causes parametric amplification of the oscillations and enhan...

Experimental laser beam profiles often deviate somewhat from the ideal Gaussian shape of the TEM(00) laser mode. In order to take these deviations into account when calculating light scattering, we propose a method for approximating the beam shape coefficients in the partial wave expansion of an experimental laser beam. We then compute scattering by a single dielectric spherical particle placed...

Laser Rayleigh imaging has been applied in a number of flow and flame studies to measure concentration or temperature distributions. Rayleigh cross sections are dependent on the index of refraction of the scattering medium. The same index of refraction changes that provide contrast in Rayleigh images can also deflect the illuminating laser sheet. By applying a ray-tracing algorithm to the detec...