Study Of Monolithic Nonplanar Ring Laser Using Ho: YAG Crystal At 2μm

Using the crystals which mixed Tm, Ho is one of the most important ways to get 2μm laser output of solid-state laser. As a highly coherent radiation spectrum, this laser has important functions in these satuations below:①Laser radar transmitter.to detect target on the ground with this radar, the resolution can be increased by 8-10 times. In addition, 2μm laser has good ability on atmospheric transmission characteristic, the laser with this characteristic has good capability of penetrability to the fog on battle ground, implement diode laser pump can miniaturize. Thus, this type of laser has very great military value.②Surgical knife .The range of 2μm laser is about 1.87-2.16μm, it covers absorption band of H₂O molecule and CO₂ molecule. This characteristic makes the 2μm laser to be absorbed by living organism easily so that it can be used in some superficial surgery without deep organism injury. This laser can be transported by optical fiber and also can work as an iatrical bistoury with endoscope.Since the Monolithic Nonplanar Ring Oscillators principle come out, it has been consummated in last 20 years and several types of band Monolithic Nonplanar Ring Oscillators laser had been developed successfully. This type of laser has several characteristic: simple and stable configuration, low noise of frequency and power, narrow of linewidth, easy adjusting, higher efficiency and single frequency output power.Firstly, this dissertation has analysed five types of laser crystals which have ability to produce 2μm laser so that ensure Ho:YAG crystal develop Monolithic Nonplanar Ring Oscillators laser which needs 1.9μm laser pump is the best choice. With the summarize of Nonplanar Ring Oscillators structure and quasi-plane Nonplanar Ring Oscillators structure and ability analysis of Semi-Nonplanar Ring Oscillators Structure tolerance machining Hreleasee Hd, Semi-Nonplanar Ring Oscillators has been confirmed to be the base configuration of Laser in this project.Secondly, using Monolithic Semi-Nonplanar Ring Oscillators Hpolarizationmatching theory, through measurement of clockwise,Hanti clockwise Ring Oscillators r and p polarization-dependent loss of polarization direction to ensure useable Hgeometrical Hstructure parameter of Monolithic Semi-Nonplanar Ring Oscillators to be the primary laser design.Thirdly, use the theory of laser beam transfer matrices to analyse stability of Hperturbation and thermostability of Monolithic Semi-Nonplanar Ring Oscillators to finish the configuration design of Laser.Finally, finish the machining of Laser and test the performance degree of the Laser by experiment.