| High power diode laser arrays have many advantages. For example, high opticalconversion efficiency, small size, high reliability and long life, etc. It has importantapplications in industrial processing, biomedical and national defense, and so on.Further more, it could be applied in much wider fields because of the continuousimprovement of its performance and the reducing cost. However, high power diodelaser arrays have drawbacks of poor beam quality and lower single emitter opticalpower due to its unique waveguide structures, which restrict its applications. In orderto solve these problems, this thesis made an in-depth study on the technologies ofbeam shaping, beam combination and fiber coupling of diode laser arrays.The beamshaping technology can improve beam quality of diode lasers; beam combiningtechnique can improve the total power of the beam; fiber coupling technology canrealize flexible transmission of the laser. The study of these technologies can facilitateand promote the applications of the diode laser in more fields.The purpose of the paper is to obtain high power and high beam quality fibercoupled laser diode modules and to realize their applications. Based on full summaryof the operating characteristics of diode lasers and the fiber coupling technology, themainly studies were focused on the following aspects:(1) The fast axis collimators of diode laser were studied. Firstly, the remainingdivergence angle of cylindrical lens was studied, and the defocus value when theremaining divergence angle reach to minimum was calculated; secondly, theparameters of aspherical cylindrical lens were calculated using Fermat's principle andthe optimization capabilities of Zemax software; Then, the index distribution functionof Gradient Index Lens was calculated; finally, the fast axis collimator alignment errorwas analyzed.(2) The remaining divergence angle of two kinds of slow axis collimators which were plano-convex cylinder lens arrays and telescope cylinder lens arrays werecompared and well studied;(3) Working principle and installation error of BTS for beam shaping had beenstudied;(4) The transform lens used in the spectral beam combining technique of thediode laser arrays were studied for the first time. The beam quality of diode laserscould approach to fiber lasers by the method of grating-external cavity of spectralbeam combining technology. However, current researches primarily focus onimproving the performance of the diode laser arrays and the diffraction efficiency. Inthis paper, the transform lens of this system was well studied, and also the optimizedtransform lens structures which can increase the efficiency of the beam combiningwere designed.(5) Currently, cm-bar is widely used in fiber coupled modules in china, but itsbeam quality is very poor because of a large number of emitters and larger slow-axisdivergence angle. In order to solve these problems, diode laser short bars were used inoptical fiber coupling for the first time in china. Two sets of fiber coupled moduleswere developed: in china there is no report on output power high than that of themodule described in this paper under the same beam quality condition. The outputpower of the module described in the paper can reached to418W whileBPP=44mm·mrad; The brighteness of another fiber coupled module is2.23MW/(cm2·sr) which is the highest value among fiber coupled diode laser arrays inchina. These work was won second prize in First International Conference onFrontiers of Laser Processing.(6) Using scalpel to do eardrum pore-forming surgery has the drawbacks aboutoperating difficulties and side effects. In order to solve these problems, the diode laserand video otoscope were firstly combined. First, the optical devices used in diodelaser myringotomy surgery was designed. Then, the devices have applied for a patentand also a prototype of the device has been manufactured. At last, the device can beproved to be used in laser surgery with the help of the video imaging.
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