To determine the relationship between the spatial channels for luminance and shape-from-stereo-disparity processing we measured disparity modulation sensitivity as a function of disparity spatial frequency for sinusoidal modulations of a field of Gabor micropatterns of differing luminance spatial frequency. We first examine the effects of contrast, spatial bandwidth and element density and show...

We studied temporal processing of chromatic and luminance perturbations of a 600-nm field, measuring both modulation sensitivity (sinusoidal frequencies from 0.25 to 40 Hz) and pulse-detection thresholds (pulse durations from 5 to 2560 msec) for mean luminances of 0.9 to 900 Td and field sizes of 0.5 degrees to 8 degrees. Chromatic stimuli were produced by antiphase modulation of lights matched...

The goal of this study was to detect the level of arousal induced by pictures of negative, positive and neutral affective valence by measuring the pupil dilation of 4 subjects. In order to detect arousal from pupil dilation data, it was necessary to reduce the effect of luminance. This required comparing the picture luminance measures to the collected pupil dilation data, and applying additiona...

The purpose of this study is to test the hypothesis that glaucoma leads to selective deficits in parallel pathways or channels. Sweep VEPs were obtained to isolated-check stimuli that were modulated sinusoidally in either isoluminant chromatic contrast or in positive and negative luminance contrast. Response functions were obtained from 14 control subjects, 15 patients with open-angle glaucoma,...

Sufficient contrast between road surface and markings is key for a safe comfortable driving experience. This calls comprehensive well established (threshold) model, which ideally results in single threshold value independent of object angular size or luminance. The model introduced by Adrian still commonly used lighting. More recently, new metrics that also predict supra-threshold visibility ha...

An element-arrangement pattern is composed of two types of elements arranged differently in different regions of a pattern. Rapid texture segregation depends on spontaneously discriminating the difference in the arrangement of the elements. Five experiments investigated the perceived segregation of patterns composed of two types of squares arranged in vertical stripes in the top and bottom regi...

The brightness of an achromatic surface with luminance S on an achromatic background with luminance B varies with S, with B, and with the luminance step deltaL at the border of the surface. In agreement with previous findings indicating that the visual system can perform as a photometer, the results of the two experiments reported here show that S and B determined surface brightness independent...

We compared reading speed with two fonts, Dutch (serif) and Swiss (sans serif). Text was displayed on a computer monitor, white letters on black, with the RSVP method. Luminance of the letters was either 146.0 or 0.146 cd m-2. Lower-case x-height of the fonts was approximately 5.5 times as large as letter acuity. At the high luminance, there was no difference between reading rates. There was a ...