| In recent years High-power Laser Diode Arrays-HLDA has been used widely in the industrial, military fields as pumping source of solid-state lasers or direct light source. At present, study on HLDA is mainly focused on two aspects. One aspect of studies includes structure design, thermal analysis, packaging techniques, these studies could improved output power development of HLDA. The other aspect is the beam shaping system design. But the beam characteristics of HLDA such as far-field distribution, beam width and divergence angle are rarely studied. These characteristics are crucial for the evaluation of HLDA beam quality and design of shaping system. This dissertation mainly studies the beam characteristics and testing technology of HLDA are studied. The main research contents of the papers are as follows:The paper summarizes the current beam characteristics development, and analyzes existent problems of current methods and techniques for HLDA. In order to solve these problems, based on Helmholtz equation and far-field distribution characteristics of single laser diode(SLD), a far-field expression of HLDA is established firstly in the paper. The different HLDAs are used to verify the expression. If the structure parameters of HLDA are known, its'transmission characteristics can be analyzed by the far-field expression. A conclusion is given on the base of theoretical analysis and the experiment results, which is HLDA's far-field intensity distribution has the bi-peak structure paralleling to PN out of the certain propagation distance. And the bi-peak structure parallel to PN can't been changed by driving current and the non-luminescence bars.In order to solve the problem of beamwidth definition in the practical application, a new method of the beamwidth solution is proposed. In the method, the facula edge points and edge curve are solved for the beamwidth solution based on improved Gaussian filter and intensity grads. The contrast experiments show that facula edge points and edge curve can be detected accurately by improved Gaussian filter. By the analysis of the beam width property of HLDA,a conclusion can been drew that the change ofωx andωy is non-linear by the change of the propagation distance before the formation of bi-peak structure of HLDA's intensity distribution and the change ofωx andωy is linear by the change of the propagation distance after the formation of bi-peak structure. The conclusion plays very important role in the research of method and system of divergence angle testing of HLDA.Aiming at the plane- luminescence characteristic of HLDA, the testing method of divergence angle using the double-facula edge curve is presented. And the device of receiving and detecting light is designed. The device is made of two hemi-toroidal probes. Two probes can detect two facula edge curves on different transmission distance. By the contrast analysis for the calculating results, the divergence angle is more reasonable and has smaller error by the double-faculas edge curve method than other methods. Two key problems discovered in the present divergence angle testing are resolved by the method and the device. One is testing error induced looking HLDA as point light source is eliminated. The other problem that HLDA is destroyed or burned because of high power is resolved.On the base of aforesaid calculation principle of beamwidth and divergence angle, the testing system of HLDA's beam characteristics is designed and implemented. The system can test the far-field intensity distribution, beamwidth and divergence angle. In order to improve measuring accuracy, the main sources of systematic error are analyzed. And in the system there are many methods used to reduce error such as taking mean, centering adjustment and intensity error compensation. Intercomparison results with standard instrument shows that measuring relative error of beamwidth is less than 5% and measuring error of divergence angle is less than 0.5°.
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