High-power Solid-state Blue Microchip Laser by Intracavity Frequency Doubling

• Main Authors: Cheng-Tso Hsiao, 蕭丞佐
• Other Authors: Sheng-Lung Huang
• Format: Others
• Language: zh-TW
• Published: 2003
• Online Access: http://ndltd.ncl.edu.tw/handle/26467997054748723115

碩士 === 國立中山大學 === 光電工程研究所 === 91 === Abstract As blue/green laser has a short wavelength radiation, it can be applied to micro-machining, laser display, high-density optical data storage, underwater communications, and so on. Large efforts have been devoted to simplify the laser system and reduce the cost. Therefore, various types of blue/green lasers have been studied, especially intracavity frequency doubling of the diode-pumped solid-state laser, which can effectively generate high blue/green laser powers with long lifetime. Among all cavity designs, direct-coated composite crystal is the most compact structure. Compare with the green laser, which is a four-level laser, blue laser belongs to a quasi-three-level system. Thus, it is more important to control the temperature of gain medium. Before the experiment, making an estimation will greatly benefit the progress and efficiency. ZEMAX was utilized to simulate the focus system and GLAD was used to model our intracavity frequency-doubled blue laser. In the experiment, we used a LD array as a pumping source and arranged suitable lens to reduce the array’s spot size. The laser crystal was mounted onto a copper mount which was cooled by the Vapochill cooling system. In addition, we also tried to rotate the crystal and obtained a peak power of 192 mW with only 4 mm cavity length. The result is the highest output power of microchip blue laser to our knowledge. Using lens duct as the pump transport optics can further miniaturize this composite-chip blue laser.