Abstract:
Ein optisch gepumpter Ultrakurzpuls-Mikrochiplaser zur Erzeugung einer Laseremission (LE) mit Femto- oder Pikosekundenpulsen weist ein Substrat (2b), ein verstärkendes Lasermedium (1), ein für optische Pumpstrahlung (PS) zumindest teilweise durchlässigen ersten Resonatorspiegel (3b) und insbesondere eine sättigbare Absorberstruktur (5) auf. Das Lasermedium (1) wird auf den Resonatorspiegel (3b) und das Substrat (2b) aufgebracht und nachfolgend in von der ursprünglichen Materialstärke auf eine Dicke von weniger als 200 μm reduziert. Um eine trotz dieser geringen Dicke befriedigende Leistungsaufnahme zu erreichen, wird die optische Pumpstrahlung (PS) so in das Lasermedium (1) eingekoppelt, dass Resonanz für die Laseremission (LE) und Intensitätsüberhöhung für die Pumpstrahlung (PS) auftreten.
Abstract:
High-power, diode-pumped solid state (DPSS) pulsed lasers are preferred for applications such as micromachining, via drilling of integrated circuits, and ultraviolet (UV) conversion. Nd:YVO 4 (vanadate) lasers are good candidates for high power applications because they feature a high energy absorption coefficient over a wide bandwidth of pumping wavelengths. However, vanadate has poor thermo-mechanical properties, in that the material is stiff and fractures easily when thermally stressed. By optimizing laser parameters and selecting pumping wavelengths and doping a concentration of the gain medium (240) to control the absorption coefficient less than 2 cm-1 such as the pumping wavelength (241) between about 910 nm and about 920 nm, a doped vanadate laser (237, 240) may be enhanced to produce as much as 100 W of output power (236) without fracturing the crystal material, while delivering a 40% reduction in thermal lensing.
Abstract:
A continuous wave Raman laser for producing visible laser output comprising: a resonator cavity; at least a first reflector and a second reflector said first and second reflectors being located at opposite ends of the resonator cavity; a laser gain medium located in the resonator cavity for generating a continuous wave fundamental beam which resonates within the resonator cavity when pumped by a pump beam from a pump source external to the resonator cavity; a solid Raman-active medium positioned in the resonator cavity for Raman shifting the fundamental beam to produce a continuous wave Raman beam which resonates within the resonator cavity; and a non-linear medium positioned in the resonator cavity for frequency converting the continuous wave Raman beam to a converted wavelength to produce a continuous wave converted beam.
Abstract:
An intracavity frequency-converted laser having an intracavity reflector situated to reflect converted radiation at a nonzero angle with respect to the optical axis. The laser includes an optical cavity (40) that defines an optical axis, a gain medium (46) for providing a fundamental laser emission, a pump source (60) for pumping the gain medium, and a nonlinear material (62) for frequency converting the fundamental laser emission to provide first and second converted beams that propagate in opposite directions within the optical cavity. An angled reflector (70) that reflects optical radiation at the converted wavelength, but is transmissive at the fundamental wavelength is situated within the optical cavity to reflect one of the converted beams along a path angled with respect to the optical axis. Reflecting the converted radiation before it propagates through the gain medium avoids absorption losses. Furthermore, interference between the reflected beam and other converted beam is avoided due to the angle of reflection.
Abstract:
A monolithic diode pumped solid-state laser (11) comprising as the laser host neodymium-doped yttrium orthovanadate (Nd:YVO4) (12, 52) or neodymium-doped gadolinium orthovanadate (Nd:GdVO4) (57, 67) operating on the F3/2 } I9/2 ( SIMILAR 914 nm or SIMILAR 912 nm respectively) transition, to which a suitable nonlinear optic material (16), such as potassium niobate (KNbO3) or beta barium borate (BBO), is bonded. The nonlinear crystal gives rise to intracavity frequency doubling to SIMILAR 457 or SIMILAR 456 nm. The microlaser is a composite cavity formed form a gain medium crystal and a nonlinear frequency doubling material which together have four spaced parallel dielectrically coated faces (14, 17, 18, 15) and which is positioned in close proximity to a diode laser pump source (13) for phase-matched harmonic generation of blue light along an axis of propagation which lies substantially perpendicular to the two faces of the composite cavity. By employing specific doping concentration-length products of lasant material and pumping the gain medium which has a specific crystalline orientation the desired efficient blue microlaser is achieved. Alternative embodiments combine the Nd:YVO4 and Nd:GdVO4 elements to enhance certain output characteristics of the laser.
Abstract:
Laser master oscillator - power amplifier system for generating high pulse energy, high average power laser pulses in the ultraviolet 191.25 - 201.25 nm and 243 - 246.25 nm spectral ranges, and in the visible 450-537.5 nm spectral range with controllable pulse duration and pulse repetition rate employ a master oscillator seed laser operating in the infra-red spectral range, and a single series connected chain of hybrid fiber - bulk optical amplifiers coupled to a non-linear frequency conversion unit to convert the laser pulses to the ultraviolet and visible spectral ranges.
Abstract:
Ein nichtregenerativer optischer Verstärker weist ein erstes optisches Verstärkermedium (5) und wenigstens ein zweites optisches Verstärkermedium (5') auf, wobei die Materialeigenschaften des ersten Verstärkungsmediums (5) wenigstens teilweise von den Materialeigenschaften des zweiten Verstärkungsmediums (5') abweichen. Erfindungsgemäß überlappen sich die Emissionsspektren der Verstärkungsmedien (5, 5') teilweise, wobei die Verstärkungsmedien (5, 5') als Festkörper-Volumenkristalle ausgebildet sind.