Yoon Geunyoung, Jeong Tae Moon, Cox Ian G, Williams David R
Department of Ophthalmology, Center for Visual Science, University of Rochester, Rochester, NY 14627, USA.
J Refract Surg. 2004 Sep-Oct;20(5):S523-7. doi: 10.3928/1081-597X-20040901-22.
To psychophysically demonstrate vision improvement when correcting higher-order aberrations with phase plates in normal eyes.
The wavefront aberrations of three nonsurgical normal eyes were measured with a Shack-Hartmann wavefront sensor. With these measured aberrations, phase plates were fabricated using a lathing technique. Theoretical improvement in retinal image quality was estimated by calculating the optical modulation transfer functions under the white light condition. Visual acuity measurements were also conducted to demonstrate improvement in visual performance after correcting higher-order aberrations with the phase plate. In this visual acuity measurement, a tumbling "E" with high (100%) and low (10%) contrast was used.
The phase plate reduced the higher-order root mean square (RMS) wavefront error from 0.39 +/- 0.09 to 0.15 +/- 0.02 microm (mean +/- standard deviation from three eyes) for a 6-mm pupil. With the phase plate, retinal image quality based on the volume of modulation transfer function under 60 cycles per degree (c/deg) was improved by a factor of 1.8 +/- 0.4 over that of the eyes with spherocylindrical correction only. Average improvement in visual acuity achieved by correcting the higher-order aberration was 0.23 lines with high-contrast letters and 1.12 lines with low-contrast letters. All subjects reported subjective improvement in image quality of the letter with the phase plate.
The phase plate effectively corrected the higher-order aberrations in normal eyes. As a result, both retinal image quality and visual acuity especially with the low-contrast letters were improved. This study demonstrated the feasibility of correcting higher-order aberrations and improving vision with customized optics.
通过心理物理学方法证明正常眼睛使用相位板矫正高阶像差时视力得到改善。
使用夏克-哈特曼波前传感器测量三只未手术的正常眼睛的波前像差。根据这些测量的像差，采用车削技术制作相位板。通过计算白光条件下的光学调制传递函数来估计视网膜图像质量的理论改善情况。还进行了视力测量，以证明使用相位板矫正高阶像差后视觉性能的改善。在该视力测量中，使用了高对比度（100%）和低对比度（10%）的翻转“E”视标。
对于6毫米的瞳孔，相位板将高阶均方根（RMS）波前误差从0.39±0.09微米降低至0.15±0.02微米（三只眼睛的平均值±标准差）。使用相位板后，基于每度60周（c/deg）以下调制传递函数体积的视网膜图像质量比仅进行球柱面矫正的眼睛提高了1.8±0.4倍。矫正高阶像差后，高对比度字母的平均视力提高了0.23行，低对比度字母的平均视力提高了1.12行。所有受试者均报告使用相位板后字母的主观图像质量有所改善。
相位板有效矫正了正常眼睛的高阶像差。结果，视网膜图像质量和视力，尤其是低对比度字母的视力都得到了改善。本研究证明了使用定制光学器件矫正高阶像差和改善视力的可行性。
