Spherical aberration and the sign of defocus.

摘要: Purpose Visual sensing of the sign defocus is important not only for rapid control accommodation but also regulating slower long-term growth eye. Methods We examined possibility that ocular spherical aberration (SA) elicits a by optical modeling image formation using principles physical optics. Results Retinal contrast, as measured area under visually weighted modulation-transfer function, depends on both magnitude and relative to SA. Image contrast greater hyperopic blur than myopic when SA positive vice versa negative. Conclusions When coupled with Wallman's hypothesis retinal activity caused inhibits eye growth, these results provide testable account myopia progression. For example, we suggest risk factor progression has negative because combination leading relatively low in defocused image. Because likelihood increases accommodation, avoiding long hours near work presence accommodative lag may help prevent onset myopia.