如何有效校正随人群起伏很大的人眼像差,提高视网膜高分辨率成像技术的人群适用范围是临床应用面临的最大难题。现有的单一波前校正器无法同时清除高阶和低阶视觉像差。针对人眼高阶像差校正需求,研制成功了169单元3 mm极间距分立式压电变形镜,并与大行程Bimorph变形镜组合,建立了一套双变形镜的人眼视网膜成像系统。系统可实现对离焦小于±4.5 D、散光小于±3.0 D的低阶像差及前8阶Zernike像差的有效校正,极大地提高了系统的人群适用范围和成像质量。以低阶像差大小作为入选标准,进行小样本量人眼视网膜成像实验,获得了近衍射极限的视网膜图像。该系统适用范围明确,便于后续临床应用。
How to effectively correct ocular aberrations which vary fast from person to person and improve the application scope of adaptive optics retinal imaging system is the biggest problem in clinical application. It is difficult for a single corrector to compensate both low order and high order ocular aberrations simultaneously. Due to the correction requirements of high order aberrations, a 169-element discrete piezoelectric deformable mirror with3 millimeters spacing is successfully developed. Combined with a large stroke bimorph mirror, a retinal imaging system with two deformable mirrors is developed. The system can compensate low order aberrations up to ±4.5diopters of defocus and ±3 diopters of cylindrical. High order Zernike aberrations up to the 8th order can also be corrected by this system. Both imaging quality and application scope are significantly improved. Taking the size of low order aberrations as inclusion criteria, a little sample is tested by the human retinal imaging experiment, and near diffraction-limited retinal images are achieved. The system has a clear application scope, which is convenient for future clinical application.