Nascimento S M, Foster D H, McKee P
Department of Physics, University of Minho, Braga Codex, Portugal.
Vision Res. 1997 Nov;37(21):2975-9. doi: 10.1016/s0042-6989(97)00137-5.
Gaussian light distributions are important stimuli for vision research, but are difficult to produce for Maxwellian viewing conditions. In this study, two binary Maxwellian-view masks which produce smooth light distributions on the retina were considered: one was an out-of-focus circular aperture; the other was an in-focus pattern of opaque squares with a prescribed size distribution. The diffraction images of the two masks on the retina were computed numerically and shown to be well described by gaussian functions. As an experimental test, a mask with the desired pattern of opaque squares was manufactured by evaporation of chromium over a quartz substrate; its quality, as assessed by micro-transmittance measurements, was found to be adequate for most visual applications.
高斯光分布是视觉研究中的重要刺激因素，但在麦克斯韦观察条件下难以产生。在本研究中，考虑了两种在视网膜上产生平滑光分布的二元麦克斯韦观察掩模：一种是失焦圆形孔径；另一种是具有规定尺寸分布的聚焦不透明正方形图案。对这两种掩模在视网膜上的衍射图像进行了数值计算，结果表明它们可以用高斯函数很好地描述。作为一项实验测试，通过在石英基板上蒸发铬制造了具有所需不透明正方形图案的掩模；通过微透光率测量评估其质量，发现其适用于大多数视觉应用。
