共查询到20条相似文献,搜索用时 234 毫秒
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提出了一种利用光学共轭关系,实现多变形镜空间匹配从而提高波前空间校正能力的自适应光学系统方案.通过理论分析给出了组合变形镜的面形描述方法,在此基础上建立了一套基于由两块相同方形排列变形镜构成的组合波前校正器的完整自适应光学实验系统.通过数值仿真研究了该系统对前35阶Zernike像差的校正效果,并且通过实验对比了组合变形镜和单一变形镜对实际静态像差的闭环校正效果.结果表明组合变彤镜可以等效为一多单元变形镜,在直接斜率控制算法下正常稳定闭环工作,校正效果明显优于单一变形镜.组合变形镜技术通过空间匹配实现了增加波前校正器驱动单元数和等效交连值,有效地提高了对波前的空间校正能力,因此可以代替高成本的单一多驱动器变形镜用于自适应光学系统中高阶像差的校正. 相似文献
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为了校正激光光束的波前像差,建立了一套无需直接探测波前信息的自适应光学(AO)系统模型,提出了一种基于实数编码的高斯变异的遗传算法(GA)用来控制61单元压电变形镜补偿波前像差,并仿真利用此算法控制61单元变形镜校正由变形镜本身产生的像差。结果表明,这种算法能够找到补偿各种像差所需的变形镜的最优面型。像差校正后,焦平面的峰值光强最多能够提高30倍。环围斯特尔比值(Strehl ratio)最多能够从校正前的0.032提高到0.96,变形镜61个驱动器后的电压值收敛性能良好。 相似文献
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提出了一种利用组合变形镜校正板条MOPA固体激光器像差的方法,并通过实验验证其有效性。通过将一个11单元的一维变形镜和一个67单元的二维变形镜组合,有效降低了单个二维变形镜波前校正过程中驱动器间的电压差,从而提高了二维变形镜的使用安全性,并在一定程度上改善了校正后波前畸变的空间分布,降低了波前畸变残差。实验结果表明,一维变形镜与二维变形镜的组合能高效地校正板条MOPA固体激光器的波前畸变,波前残差均方根值小于0.08 m,远场光束质量因子可达1.67。 相似文献
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子孔径合成光学成像系统像质评价研究 总被引:6,自引:5,他引:1
由于子孔径合成光学成像系统出瞳波前离散,成像特征有异于常规光学系统.对比了两种子孔径合成光学成像系统的像质评价方法,其一是直接利用干涉仪实测获得的整体出瞳波面参量,拟合成泽尼克多项式,通过快速傅里叶变换获得光学系统的调制传递函数;其二是对子出瞳波面在像面复振幅分布的衍射直接积分叠加计算系统调制传递函数.对于离散出瞳波前,拟合的泽尼克多项式不可避免有较大误差,由此计算获得的调制传递函数与实际测量值有较大区别.设计并制造了一个三子镜合成的成像光学系统,在此基础上用ZYGO GPI干涉仪验证并对比了使用两种方法对像质计算的特点.结果表明,子出瞳波面直接衍射积分叠加法的精度更高,但计算量大,且要获得更高的像质评价精度,应使用更适于表达离散不规则形状子出瞳波前的波函数. 相似文献
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We report what is to our knowledge the first laboratory experiment that shows the use of a pyramid wavefront sensor to cophase and align segmented mirrors having three degrees of freedom per segment, i.e., piston, tip, and tilt. In the laboratory the iterative alignment procedure reached a wavefront residual error of about 10 nm. The residual error was equally distributed between piston, tip, and tilt. These results demonstrate that the pyramid can successfully simultaneously sense the piston, tip, and tilt of a segmented mirror. This last feature makes this technique very attractive in phasing and aligning astronomical segmented telescopes such as extremely large telescopes currently under extensive studies. 相似文献
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We describe a concept of using segmented adaptive optics (AO) to correct the higher-order wavefront aberrations (HOWAs) in an atmospheric turbulence condition. The effects of piston and tip-tilt corrections are analyzed by numerical simulation. An experiment test-bed is built for verification. Seven spatial beamlets are combined into a hexagonal array by use of a pyramid, and an active segmented mirror is used for phase modulation. The AO control is implemented by stochastic parallel gradient descent (SPGD) algorithm. Experimentally, after segmented AO is enabled, the HOWA in warmed air environment has been effectively corrected and the peak intensity of far-field has been enhanced by 5 times. 相似文献
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Alexander Pichler Pierre Raymond Marc Eichhorn 《Applied physics. B, Lasers and optics》2014,115(3):325-334
In most applications of laser technology and optics the beam quality, the ability to focus a laser beam and the achievement of a good optical resolution play an important role. The compensation of distortions using adaptive optics requires fast wavefront measurement. Classical wavefront analysis schemes use matrix operations, which show a nonlinear computation time dependence with matrix size, making it difficult to achieve high-speed control loops at a high resolution. A novel wavefront sensor system is presented using a massively parallel k-nearest neighbor classifier chip in an embedded hardware setup. Our miniaturized sensor is able to detect one optical distortion within about 80 μs allowing its use for high-speed adaptive optics applications. 相似文献
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The segmented mirror telescope is widely used. The aberrations of
segmented mirror systems are different from single mirror systems.
This paper uses the Fourier optics theory to analyse the Zernike
aberrations of segmented mirror systems. It concludes that the
Zernike aberrations of segmented mirror systems obey the linearity
theorem. The design of a segmented space telescope and segmented
schemes are discussed, and its optical model is constructed. The
computer simulation experiment is performed with this optical model
to verify the suppositions. The experimental results confirm the
correctness of the model. 相似文献
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Graded-index (GRIN) lenses serve as a key component for miniature endoscopes because of their small diameters and ease of assembly. However, the nonaplanatic nature of GRIN lenses causes inherent spatial aberrations that lower image resolution and sharpness. Here we present the diagnosis of the aberrations in GRIN probes and the use of adaptive optics to compensate for the wavefront errors in the endoscope. Two different operation schemes based on preset and in situ measurements are demonstrated, both resulting in a substantial reduction of the wavefront error from 0.42 to <0.1 μm. 相似文献
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Booth MJ 《Optics letters》2007,32(1):5-7
In some adaptive optics systems the aberration is determined not by using a wavefront sensor but by sequential optimization of the adaptive correction element. Efficient schemes for the control of such systems are essential if they are to be effective. A scheme is introduced that permits the efficient measurement of large amplitude wavefront aberrations that are represented by an appropriate series of modes. This scheme uses an optimization metric based on the root-mean-square spot radius (or focal spot second moment) and an aberration expansion using polynomials suited to the representation of lateral aberrations. Experimental correction of N aberration modes is demonstrated with a minimum of N+1 photodetector measurements. The geometrical optics basis means that the scheme can be extended to arbitrarily large aberrations. 相似文献