Phase control method and control circuit used for large array element coherent combination

Abstract

The invention provides a phase control method used for large array element coherent combination. The phase control method is characterized in that a modulation signal of a phase control algorithm is subjected to orthogonal coding and single-frequency modulation; compared with a multi-dithering algorithm, debugging signals with a plurality of frequencies are not needed, so that the algorithm is simplified and hardware is convenient to realize; compared with a single-dithering algorithm, the quantity of paths subjected to phase debugging within a certain time period is increased and the control bandwidth is improved. The invention further provides a phase control circuit used for the large array element coherent combination; the phase control circuit comprises a programmable chip 1, a digital to analog converter 3, a control signal conditioning circuit 4, an analog to digital converter 5 and an input signal conditioning circuit 6, and is characterized by further comprising a multiplexer 2. Under the condition that the number of output pins of the programmable chip 1 is limited, the maximum control path quantity of a control circuit is improved, and phase control of a hundred-path-level large array element coherent combination system can be realized.

Description

technical field [0001] The invention relates to coherent combining of lasers, in particular to a phase control method and a control circuit for coherent combining of large array elements. Background technique [0002] Laser coherent combination technology can break through the limit of single-channel laser output power, improve laser power and brightness, and is currently a research hotspot in the field of high-energy laser technology. The active phase control-based master oscillator power amplifier (English name is Master Oscillator Power Amplifier, MOPA for short) structure is a commonly used laser coherent combining system (see invention patent CN 1688069 A). The system structure is as figure 1 As shown (refer to literature: Liu Zejin, et al. Research on coherent combining of fiber lasers with active phase control. China Laser, 2009,36(3):518-524.), the system mainly includes seed laser 1 / , laser beam splitter 2 / , phase modulator 3 / , laser amplifier 4 / , Laser...

AI Technical Summary

Problems solved by technology

[0007] (1) The control bandwidth of the SPGD algorithm and the single-frequency dithering algorithm decreases rapidly with the bandwidth of the number of control channels;

[0008] (2) The multi-jitter algorithm requires multiple jitter frequencies, the circuit debugging is cumbersome, and the requirements for the response frequency range of the phase modulator are too high;

[0009] (3) The existing phase control circuit is based on a single programmable chip, the number of control channels is limited, and it is difficult to realize the phase control of a coherent combination system with hundreds of channels.

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