Optical and Laser Components
1. Flowtubes, Monoblocks and Specular Reflectors for Lamp- and Diode-based Pump Chambers.
Flowtubes and Monoblocks are an essential component of the flashlamp-pumped pump chambers; they carry out the following functions:
– Provide flow-channel for cooling liquid;
– Absorb (filter-out) undesired UV-radiation, reducing heat load, thermal lensing effect and protesting the active medium from long-term solarization;
– Provide internal support for BaSO4 reflectors;
– Blocking lateral stimulated emission, which can depopulate the laser rod and significantly reduce amount of the extracted energy in Q-switched mode. For the Q-switched Nd:YAG Laser Samarium-doped Glass is the material of choice, because it attenuates lateral depumping effects, thus avoiding super luminescence phenomena and absorbing undesired UV radiation.
Cerium Glass and Europium Quartz Glass are also interesting doping materials, because they absorb undesired UV-radiation and can additionally re-emit this energy in the useful spectral range. For free-running lasers, Duran and Quartz Glass are the materials of choice for fabricating the flowtubes, while undoped-YAG and Sapphire can also be used when harsh conditions warrant.
Flowtubes and monoblocks are machined out of a block of glass with highly polished interior and exterior surfaces. The channels containing the laser rod and flashlamps are deep-bored with tight control of dimensions and tolerances on parallelism and perpendicularity. In case of Sm- or Eu-doped glass, the monoblocks are subjected to ion-exchange strengthening in accordance with instructions of glass manufacturer.
All shapes and configurations of monoblocks are available including multi-channel cylindrical, ellipsoid, shotgun, etc. sections with flat or indented end-surfaces for reliable sealing. Please contact us with your specific requirements.
The monoblocks can be used as part of diffuse pump chambers with BaSO4 reflectors. In addition, the polished exterior cylindrical or elliptical surfaces can be coated with Cu/Ni-protected Silver or Gold coating to form the high efficiency Specular Reflector, with some standard configurations available on a short notice.
Presence of strong thermo-optical effects in high power diode pumped lasers presents a challenge in obtaining high output power with low-order modes. In various Nd:YAG laser configurations like rod, slab or disk lasers thermally-induced refractive index changes lead to lensing, aberrations and birefringence. For power scaling of diode pumped solid state lasers the uniform pumping configuration and effective thermal management are required.
For better pumping and cooling management of diode-pumped solid-state lasers, our preferred vendor has developed a range of state of the art Sapphire and Fused Silica reflector flowtubes for axial uniform pumping. The barrel surface of flowtubes is coated by Cu/Ni-protected, highly reflective Gold layer. For uniform distribution of laser diodes pumping radiation within laser rod, multiple configurations of flowtubes have been developed. Due to high manufacturing precision combined with innovative know-how, these reflectors demonstrated reduced thermally-induced effects of lensing and aberration, and improved output power and optical-to-optical efficiency of the laser.