| As the driver of the Inertial Confinement Fusion (ICF), the high power solid-state laser employs a lot of large aperture optical components. To guarantee the safe function, the specification of the fabrication quality is a key problem, which is also the precondition of the high quality laser beam. In this dissertation, two kinds of new specifying parameters, i.e., the power spectral density (PSD) and the phase gradient, have been analyzed in detail Furthermore, a kind of new testing method, sub-aperture stitching interferometer, has been studied The main results have been summarized as follows:1. Break the wavefront distortion into three different spatial frequency regions. The relationship between the spatial frequency region of the wavefront distortion and the optical characteristics of the laser beam has been studied2. According to the B-T theory, the principle of the small-scale self-focusing has been discussed in detail. The calculation process of the B-integral has implemented. The phenomenon of the filamentary structure in the high power laser beam has been explained by the B-T theory. The relationship between the number of the filaments and the power of the laser system has been specified during the calculation process.3. To employ the power spectral density (PSD) as a kind of new parameter to specify the Jarge aperture optical components employed in the ICF drive system, the definition and the calculation method of this parameter have been analyzed. The model of the numerical simulation method of the PSD has been constructed.4 PSD has been used to calculate the Optical Transfer Function (OTF) of thelarge aperture interferometer, which used in the test work to specify the large aperture optical components. The influence of the wavefront distortion on the beam quality has been discussed, and the result shows that different PSD analyzed results will be obtained while the different distortion of the wavefront presents. By using the PSD test and analyzed method, some typical large aperture optical components, which have been employed in the ICF drive system, have been specified.5. In allusion to the situation that there is not a suitable parameter to connect with the wavefront distortion with the focusing characteristics of the laser beam the phase gradient is introduced into the optical test work. The method to bring forward a phase gradient standard has worked out6. The phase gradient test model has been presented. By using the phase gradient test model, some typical large aperture optical components to be used in the ICF drive system, have been specified7. To resolve the difficulties that exist in the optical test work, a kind of new test method has been studied. The sub-aperture stitching interferometer can reduce the cost on the test equipments and improve the spatial resolution, which are very difficult to be resolved by using the large aperture interferometer. The model of the sub-aperture stitching test has been constructed and the feasibility of the stitching interferometer has been approved.8. Since the precision of the test system is the guarantee of the specifying work, the precision of the sub-aperture stitching test system has been studied in detail. According to the statistic method and the regressive analyzing method, the precision analyzed method has been worked out.9. Plenty of experiments have been performed to validate the stability and the precision of the sub-aperture stitching interferometer system The large aperture optical component' test has been done too. These experiments are the preparation of the corning specifying works to test the components of the ICF system using the sub-aperture stitching interferometer.10. The software has been built up, which includes several kinds of functions, such as the PSD analyses, phase gradient analyses, P-V and RMS calculation and sub-aperture stitching test.One of the most important fruit of this dissertation is to make the optical test work from the spatial domain to the frequency domain. Another o...
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