单透镜高分辨成像系统的研究和设计

Research and design of single lens high resolution imaging system

单片凸透镜由于存在较大像差,在实际应用中难以单独成像,相对孔径越大,单片凸透镜的成像质量越差,通常使用多片透镜以进行像差校正。针对单凸透镜成像质量差的的问题,提出了采用液晶空间光调制器和微扫描光楔实现单片凸透镜的高分辨成像。采用Zygo干涉仪测量单透镜波前,结合Zemax软件模拟得到经单透镜后的畸变波前,利用泽尼克多项式描述畸变波前,并绘制对应共轭波前的灰度图加载于液晶空间光调制器上,校正波像差;通过旋转楔角为21″的光楔进行2×2微扫描,将四幅低分辨率图像经过Keren配准后以结构适应的归一化卷积法合成为一幅高分辨率图像。实验结果表明,图像分辨率MTF50达到1 348 LW/PH,成像质量明显提高。

Single convex lens can image objects outside of the focus length, there are a variety of problems, such as different forms of aberration and low resolution. The larger the aperture is, the lower full field MTF is. Multiple lenses are used to correct aberration. The liquid crystal spatial light modulator and micro scanning optical wedge were proposed to realize high resolution imaging with the single lens.It is suggested to use Zygo interferometer to measure single lens with Zemax software simulation wavefront, the Zernike polynomials was applied to describe the distortional wavefront, the conjugate grayscale map was drawn to load in the liquid crystal spatial light modulator and calibrated wave aberration. The optical wedge of 21″ was rotated to complete 2 ×2 micro scanning. Four low resolution images, through Keren registration and structure-adaptive normalized convolution algorithm, ultimately were synthesized into a high resolution image. The image resolution is promoted to 1 348 LW/PH at MTF50, which proves its effectiveness.