Westheimer Gerald
Division of Neurobiology, University of California, Berkeley, CA 94720-3200, USA.
Biomed Opt Express. 2024 May 8;15(6):3670-3680. doi: 10.1364/BOE.525766. eCollection 2024 Jun 1.
Multi-focal intra-ocular or contact lenses, intended to increase depth of focus, conventionally have annular zones of additional refractive power, generating wavefront rings of coaxial spherical surfaces. It is, however, possible to influence depth of focus by changing not only the curvature of the wavefront, refractive power, in the annulus, but also the tilt, circularly symmetrical linear radial deviation imposed on the spherical wavefront. Employing the example of a single annulus bifocal, retinal image light distributions in the two regimes are calculated, using standard diffraction theory. Four measures of retinal image quality in through-focus scans show that plus power additions and wavefront tilts operate almost interchangeably. In testing these lenses, attention needs to be paid to the detailed operating characteristics of measuring devices of the Shack-Hartmann type to ensure that their grain and precision is compatible with the framework of the analysis.
旨在增加聚焦深度的多焦点眼内透镜或隐形眼镜，传统上具有附加屈光力的环形区域，会产生同轴球面的波前环。然而，不仅可以通过改变环带中波前的曲率（屈光力），还可以通过改变施加在球面波前上的倾斜度（圆对称线性径向偏差）来影响聚焦深度。以单环双焦点透镜为例，利用标准衍射理论计算了两种状态下的视网膜图像光分布。通过聚焦扫描得到的四种视网膜图像质量测量结果表明，增加正屈光力和波前倾斜几乎可以相互替代。在测试这些透镜时，需要注意夏克-哈特曼型测量设备的详细操作特性，以确保其粒度和精度与分析框架相匹配。
