Port M, Refson K, Minards J
Department of Optometry and Visual Science, City University, London, UK.
Ophthalmic Physiol Opt. 1995 Sep;15(5):457-61.
A Nissel +1.75 D PS45 lens' label power seems to be made up of about +0.75 D distance and +0.75 D near addition. There are individual variations which will depend on pupil size, corneal shape, lens position and ocular aberrations. When a +0.75 Bausch & Lomb U3 lens was used as a control, there was also a significant increase in 'accommodation' measured (+0.75 D), but this could not be explained. When two other lenses with an aspheric surface were studied, they also showed a near addition effect. In this supplementary study the changes were explained by changes in spectacle accommodation. A lens with two spherical surfaces did not show the expected increase in spectacle accommodation. Astigmatism, as a general rule, was not corrected by the PS45 lens, although the very occasional case did show some reduction. Visual acuity and contrast sensitivity at 8 cpd and 3 cpd were not significantly affected when compared to the control lens.
一片尼塞尔+1.75 D PS45镜片的标称度数似乎由约+0.75 D的远用度数和+0.75 D的近用附加度数组成。存在个体差异，这取决于瞳孔大小、角膜形状、镜片位置和眼像差。当使用一片+0.75的博士伦U3镜片作为对照时，测量到的“调节”也有显著增加（+0.75 D），但这无法解释。当研究另外两片具有非球面表面的镜片时，它们也显示出近用附加效应。在这项补充研究中，这些变化是由眼镜调节的变化来解释的。一片具有两个球面的镜片并未显示出预期的眼镜调节增加。一般来说，PS45镜片不能矫正散光，尽管极少数情况下确实显示出一些散光减少。与对照镜片相比，8周/度和3周/度时的视力和对比敏感度没有受到显著影响。
