个体眼结构的横向色差随外置光阑偏心和视场的变化

由角膜地形图计算了8只人眼视轴与光轴的夹角。依据实际测得的角膜地形图数据、人眼波像差、眼轴数据以及计算的视轴与光轴间夹角，运用ZEMAX光学设计软件构建了考虑视轴方向的个体化眼模型。基于这些眼模型，研究了外置人工光阑相对视轴偏移在中心凹附近所引入的横向色差变化规律。研究表明，横向色差随人工光阑的偏移量线性增加；8只人眼存在一定的个体差异，横向色差随人工光阑偏移量增加的速率在5.46 arcmin/mm ~5.95 arcmin/mm 范围之间，平均值为5.7 arcmin/mm。然后研究了在420 nm至700 nm波段边缘横向色差随入射视场角的变化规律。在鼻侧和颞侧20°视场范围内，8只人眼的横向色差平均以0.36 arcmin/deg 的速率随视场角增加而增加, 不同个体的增长速率有所差别，变化范围在0.32 arcmin/deg~0.44 arcmin/deg 之间。同时横向色差在长波段的变化要比短波段处缓慢。 关键词：视觉光学；横向色差；个体化眼模型

The variation of transverse chromatic aberration with the displacement of artificial stop and eccentricity based on the individual eye model

The angle between visual axis and optical axis is calculated from the cornea data for eight eyes. According to the measurements of the corneal surfaces, the optical axis lengths, the wavefront aberrations and the angle obtained from calculation, the individual eye models involving the angle between visual axis and optical axis are constructed with ZEMAX software. The constructed eye models are then used to investigate the variations of transverse chromatic aberration (TCA) at fovea with the displacement of artificial pinhole from the visual axis. The result shows that TCA increases with the displacement linearly at an average ratio of 5.7 arcmin/mm, with some differences among the eight eyes over the range from 5.46 arcmin/mm to 5.95 arcmin/mm. Then, we investigate the variation of TCA with eccentricity over the spectrum from 420 nm to 700 nm. Across the field of view of 20°both at nasal and temporal, TCA increases with the eccentricity at an average ratio of 0.36 arcmin/deg for the eight eyes over the range from 0.32 arcmin/deg to 0.44 arcmin/deg. And the variation of TCA is slower at the end of long wavelength than that at the end of short wavelength.