Peter Greve

Emission Characteristic Of High Power Kr/Xe-Flashlamps

High power solid-state lasers are still being pumped mainly by gas discharge lamps filled with krypton, xenon or some mixture of gases. The radiation of these lamps is trans-ported to the laser rod by closed coupling or by the reflecting properties of an elliptical reflector in the laser cavity.

Cw-Intracavity Frequency Doubling With Different Crystals

The cw second-harmonic generation (SHG) properties of three nonlinear crystals were in-vestigated: KTP, BBO and LiI03. Therefore we built up a special Nd:YAG laser resonator producing a beam waist at the crystal location by an intracavity focusing lens and so increasing the intensity at the SHG crystal. Another advantage of the used resonator design is the possibility of coupling out the whole generated second-harmonic power. The obtained power outputs at 532 nm were greater than 10 W for KTP and about 1 W for BBO and LiI03.

Preliminary results on the approval of a switchable 1064/532 nm laser

Lasers for medical applications can be classified into five interaction groups (Table 1): - photochemical interaction - thermal interaction/coagulation - cutting / vaporisation - photoablation - electromechanical interaction / disruption Each interaction mechanism has typical interaction times and power levels. Typical laser systems are established within each field. Tissue coagulation is done on the time scale of 0.01 - 10 seconds with continuouswave (cw) lasers. Depending on the penetration depth needed a laser in the green, near infrared or for infrased region in used. For 10.6 jm (CO2 -laser) the penetration depth is so small, that even medium intensities effect vaporisation (Fig. 1).

Fiberoptic Interferometer For Relative Phase Detection

The recent developments in the field of high-power semiconductor lasers open a broad area of applications, medical, measurement developments, pumping of solidstate lasers and furthermore. For almost all of these applications it is necessary to collimate and handle the laser beam power by optical elements. On the other side high power laser diodes are mostly gain-guided multi-stripe-arrays exhibiting wavefront aberrations which are a function of drive current, temperature, optical window in the package and even might differ from sample to sample. In order to correct for these aberrations and get an optimized optical system not only the beam intensity distribution has to be known, but also the relative phase of the wavefront in comparison to an ideal spherical wave. A fiberoptic interferometer is described which measures the relative phase of the radiation field locally with high resolution. Summing up the data and assuming a rectangular symmetry the complete wavefront can be reconstructed.