| Summary: | 碩士 === 國立高雄師範大學 === 光電與通訊工程學系 === 102 === Using red, green and blue laser as light sources of display has attracted a lot of attention nowadays. The narrow bandwidth, large color gamut, high resolution, and high brightness are the advantages of the laser source. But the output power of the single-mode semiconductor laser diode in blue and green region are too low to meet the needs of laser display. Therefore, study of suitable green and blue laser is a very important issue for laser display now.
Ytterbium-doped fiber laser is compact, light, high efficiency, and good for heat dissipation. Even with high output power, it still maintain a good beam quality. Although the emission spectrum covers form 900 to 1200 nm which can generate blue and green laser by doubling frequency technique. But the shortest wavelength of Yb:fiber laser is 974 nm. While the wavelength is shorter than 976 nm, the emission cross section becomes smaller than the absorption cross section, and is closer to quasi-three-level laser scheme which causes serious re-absorption loss. This is why it is difficult to generate short wavelength Yb:fiber laser.
In this study, LAD software was used to analyze the suitable pump wavelength, fiber length, grating reflectivity, and the cutting angle of fiber end face for 960 nm Yb:fiber laser. We successfully established a 914-nm Nd:YVO4 laser as the pump source for Yb:fiber laser. The slope efficiency is 30.3%, the laser threshold is 10 W, and the max output power is 4.57 W. From the simulation results, a 960-nm Yb:fiber laser can be generated by using 914-nm laser end-core-pumped scheme, with 0.5 W threshold, and 76.5 % slope efficiency .
Key words : Ytterbium-doped fiber、Fiber laser、Laser display
|
|---|
