A new adaptive optics (AO) system for controlling the mode profile of a diode-laser-pumped Nd:YAG solid laser has been set up in our laboratory. A 19-element piezoelectric deformable mirror (DM), which is used as the rear mirror of the solid-state laser, is controlled by a genetic algorithm (GA). To improve the system convergence rate, the GA optimizes the first 10 orders of Zernike mode coefficients rather than optimize 19 voltages on the DM. The transform matrix between the 19 voltages and the first 10 orders of Zernike mode coefficients is deduced. Comparative numerical results show that the convergence speed and the correction performance of the AO system based on optimizing Zernike mode coefficients is far better than that of optimizing voltages. Moreover, experimental results showed that this AO system could change TEM(10), TEM(11), and TEM(20) transverse modes into a TEM(00) mode successfully.

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As an active device, deformable mirror has been successfully used in adaptive optical systems to compensate phase aberrations and improve beam quality. However, it is often limited to correcting the phase aberrations for a flat reference wavefront. In this paper we present a new adaptive beam intensity profiles control technique based on the combination of a 19-element deformable mirror and a global genetic algorithm. This algorithm can adaptively adjust the voltages of the 19 actuators on the deformable mirror to reduce the difference between the target beam shape and the actual beam shape. The numerical simulations results show that within the mechanical constraints of the deformable mirror, this technique can create the given beam intensity profiles in a focal plane.

We propose a kind of wavefront sensing technique by means of binary intensity modulation. A digital micromirror device operates as a binary intensity modulator and a pinhole works as a binary-aberration-mode filter. Through modulating intensity distribution of incident light, light emitting from the pinhole is capable of containing information on binary aberration coefficients. With the amount of light acquired by a single detector, the coefficients of binary aberration modes for reconstructing incident wavefront can be calculated. Differing from the conventional wavefront sensing technique, this method turns the complex two-dimensional wavefront sensing into simple total-light-intensity detection. The simulation experiment has validated the feasibility of the theoretical model.