Tomohiro Takase

Highly efficient operation of diode laser transversely pumped high-power Nd:YAG rod laser

We are developing rod-type all solid-state laser with average power more than 10 kW as a tool for high speed and highly precise material processing such as cutting and welding. We developed a rod-type all solid-state laser system with average power of 3 kW level and succeeded in attaining an average power of 3.3 kW with multi head configuration with combined mode of CW and QCW operation. We also obtained electrical- optical efficiency of 19% in CW operation and that of 17% in QCW operation in the region of average power of 0.8 kW to 1.0 kW.

Efficient 1.8-kW diode-pumped CW Nd:YAG rod laser

Summary form only given. As laser diodes (LDs) have recently been rapidly increasing their output power, high power all solid-state lasers based on LD pumping are currently subject to active R&D. One target of a LD pumped solid-state laser is an easy maintenance, compact, high power laser system. A laser system with multi-kW output power could be a useful tool for welding, cutting and drilling. In order to develop compact high-power solid-state lasers, pump power density is the key parameter. In our previous paper, we reported the development of a 1-kW CW Nd:YAG rod laser with pump power density up to 380 W/cm, which is, to our knowledge, the highest pump power density for a rod type Nd:YAG laser. In this paper, we report the experimental results of 1.8-kW operation with pump power density up to 380 W/cm, and experimentally investigate the energy transfer from electrical input to laser output.

Second Harmonic Generation of a Copper Vapor Laser Using an Anamorphic Optical System

We analyzed theoretically the conversion efficiency of a second harmonic generation (SHG) in a copper vapor laser (CVL) at 510.6 nm using the β- BaB2O4 crystal and the anamorphic optics. It was found that a higher conversion efficiency compared with that of a conventional spherical focus can be achieved using several anamorphic systems with different anamorphicities.

Efficient 2-kW diode-pumped cw Nd:YAG single rod laser

We report an output power of 2 kW from single 203-mm diode-pumped Nd:YAG laser rod. The optical-optical efficiency is 47%, the electrical-optical efficiency is 22%.

Efficient 5-kW diode-pumped cw Nd:YAG rod laser

Summary form only given. High-power and high-efficiency all-solid-state lasers based on LD pumping are current subjects of active R&D. Multi-kW LD-pumped Nd:YAG laser systems are much expected as welding, cutting and drilling tools. In these applications, total efficiency is one of the most important key-factor. In this paper, first, we report the laser characteristics with 8-inch Nd:YAG rod, after that we discuss the stable and effective configuration of the multi-head oscillator.

High-efficiency operation of diode-pumped high-power Nd:YAG rod laser

We are developing rod-type all solid-state laser with average power more than 10 kW as a tool for high speed and highly precise material processing such as cutting and welding. In this year, we developed rod-type all solid-state laser system with average power of 3-kW level and succeeded in attaining an average power of 5.1 kW with CW operation and 3.3 kW with combined mode of CW and QCW operation. We also obtained electrical-optical efficiency of 22% in CW operation and that of 26% in QCW operation with average power of 2 kW.