液晶空间光调制器对真实人眼畸变波前的校正

Correction of aberration in eyes by liquid crystal spatial light modulator

基于液晶空间光调制器波前调制量大,像素密度高,驱动电压低等优点,用液晶空间光调制器作为校正眼像差的关键元件,研制了用于人眼畸变波前探测和校正的自适应光学系统。介绍了液晶空间光调制器的波前调制原理,利用ZY-GO干涉仪测定了位相调制和灰度级的关系曲线。分别用Hartman-Shack波前探测器和高分辨率液晶空间光调制器探测和校正人眼的波前畸变,对近视5m-1(500度)的人眼进行了自适应校正实验。校正后,系统的波前误差为0.086λPV和0.013λRMS,达到了系统的衍射极限,并可清晰地分辨眼底原来模糊的细胞。实验结果表明,液晶空间光调制器可以有效校正畸变波前,达到提高成像质量的目的。

By taking the advantages of a Liquid Crystal Spatial Light Modulator（LCSLM） in large stoke, high density and a lower voltage driver, an adaptive optical（AO） system for correcting the aberration of the human eye was developed by using the LCSLM as a key element. The modulation principle of LCSLM was introduced and the relation curve between the phase modulation and the drive voltage was also measured by a ZYGO interferometer. Then, the Shack-Hartmann wavefront sensor and LCSLM were used for aberration detection and correction, respectively. For a subject eye with 5 m-1（5D） mopia, the wavefront error is reduced to 0.086λ PV and 0.013λ RMS after adaptive optics （AO） correction, which has reached the diffraction limit. Furthermore, the blurred photoreceptor cell on the fundus oculi is clearly imaged on a CCD camera. These results show that the LCSLM based adaptive optical system has the ability of correcting the aberration of the human eye efficiently, and the quality of image is also improved a lot.