Research On Grating Tiling System For Large-scale Precision Grating

Chirped-pulse amplification(CPA) is an important method for the implementation of ultra-short pulse laser energy amplification. However, the damage threshold and calibre of the grating in a CPA compressor limits the energy of the output pulse. Although multilayer dielectric(MLD) holographic grating has the best performance among existing methods for CPA compressor, it is difficult to manufature it on a large scale on the order of meters. Hence, to improve the energy of the output pulse in large-scale grating, researchers around the world mostly employ grating splicing. Precision array grating is regarded as one of the core aspects of grating splicing, and its splicing system has been extensively studied.Data obtained by real-time supervision of the relative pose of the gratings offers an effective basis for guaranteeing the real-time stability of array grating. This paper thus discusses real-time testing of the relative pose on a discontinuous plane, the relationship between the environmental factors and the stability of the array grating, the design of a grating splicing system, and the experimental demonstration of the performance of the device. The contents of this paper are as follows:1. Based on the findings of previous studies on compensating for the matching of array grating in accordance with the co-plane principle of plane space, this paper proposes a method for measuring the discontinuous independent bounded interface relative pose based on vector error restraint principles. It also analyzes the restraint level and the stability of the method used to test a device with zero drifting errors. This provides a theoretical basis for testing the relative pose of electromechanical grating.2. A complete set of array grating splicing system is designed, including the support structure, testing methods, and feedback control. The main structure of the system comprises a grating support frame that combines a back riser and a tetrahedral truss. This enables the achievement of maximum vibration response in the device—something that cannot be otherwise obtained on the grating surface—and an acceptable natural frequency. The method for measuring the discontinuous independent bounded interface relative pose based on vector error restraint principles is used to test the spatial relative pose of the grating to verify the feedback control. For this purpose, the latch compensation method and the four-point centre difference method are used to improve the incremental PID control algorithm, the response speed, and the anti-interference ability of the grating splicing control system.3. To specify the design direction of the grating splicing device, the structural stability is analyzed from two perspectives. First, the operation environment of the array grating is tested to determine the factors that may induce vibration and to evaluate the temperature load. Data on the experimental environment are used as the basis for analyzing the relationship between the environmental factors that affect the stability of the array grating and its functionality. Secondly, based on the general form of the grating equation, the effects of the grating deflection angle on the beam direction in a laser-compressed pool environment is examined.4. The dynamic stiffness method is used to determine the weak link that affects the structural stability of the grating splicing device, and the related parameters are used to optimize the design to improve the natural frequency. The differential method is also used to analyze the transmission chain of the device to reduce the error transmission coefficient X in the rotational environment using the optimized design of the transmission unit. This is done to improve the transmission stability.5. A 2×1 grating splicing model machine was developed and experiments were conducted to test its performance. To determine the relative pose of the gratings, the results of the electromechanical tests were compared with those of spot test calculations. The use of electromechanical testing methods to measure the relative pose of the independent discontinuous bounded interface based on vector error restraint principles was also demonstrated. Furthermore, the grating pose was calculated by investigating the change in the relative distance between two spots, and the self-stability performance of the grating device was demonstrated. By comparing the grating stability in the open and closed states, the performances of the real-time stability and the method for controlling the grating splicing system were examined.The stability of array grating is one of the important factors that determine the effectiveness of CPA-laser-compressed shooting. A method is thus proposed for testing the discontinuous independent bounded interface relative to the pose. In addition, a grating splicing system with improved stability and high-calibre array grating is developed.