| Diode-pumped solid-state lasers have been the fastest growing laser in recent years and applied in important areas of national economy such as scientific researches, military affairs and industry and so on due to its advantages in high efficiency, excellent beam quality, high reliability, compact configuration, and long lifetime. Moreover, all-solid-state red lasers have been attracting great attention in the field of laser biomedical, color display, laser storage and pumping sources for tunable lasers.In this thesis, through using directly pumped technology, we achieved a cw Nd:YVO4TEMoo laser operating at1.34μm by double-end polarization pumping composite crystal. Through designing three-mirror folded cavity and optimizing the experimental conditions, the maximum output power of12.4W was obtained under pump power of51W. On this basis, we achieved a cw TEM00laser operating at671nm by designing Z shaped four-mirror folded cavity, and using a type-I critical phase-matched LBO crystal as the nonlinear crystal for intracavity frequency doubling. Maximum output power of5.2W was obtained under pump power of42.5W, with optical-to-optical conversion efficiency of12.2%. The stability of the red laser output was better than±2.5%in the given one hour.The main contents of the dissertation are as follows:Chapter1:IntroductionThe progressing history and developing tendency of laser diode pumped solid state lasers were reviewed. Especially the application and research status of1.3μm and671nm red lasers were introduced in detail. Furthermore, the development and research status of directly pumped technology were summarized briefly.Chapter2:All-solid-state Nd:YVO4laser at1.3μmFirst, many properties of the Nd:YVO4crystal were introduced. Then the sources of the thermal effect was analyzed in theory, and how to reduce it was put forward. Furthermore, the temperature distribution of the crystal used in our experiment was simulated and the thermal focal length was measured. Finally, the three-mirror folded cavity was designed according to the measurement of the thermal focal length and principles of the designing the cavity. By optimizing the experimental conditions, the cw TEMoo laser operating at1.34μm of maximum output power of12.4W was obtained and its performance indexes are measured.Chapter3:All-solid-state Nd:YVO4/LBO red laserFirst, different nonlinear crystals for intracavity frequency doubling were compared, a type-I critical phase-matched LBO crystal was selected as the nonlinear crystal for intracavity frequency doubling. Then the physical properties, chemical properties and optical properties of LBO were introduced in detail. Taking into account of influencing factors on frequency-doubling efficiency, and combining with principles of the designing the cavity, Z shaped four-mirror folded cavity was designed. The beam waist in Nd:YVO4and in LBO were controlled by changing the length of cavity in order to achieve the best efficiency of frequency-doubling. Finally, the cw TEM00red laser operating at671nm of maximum output power of5.2W was obtained under pump power of42.5W, with optical-to-optical conversion efficiency of12.2%. The stability of the red laser output was better than±2.5%in the given one hour. Chapter4: Conclusions and outlook... |
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