C53568: Pattern glare

Some individuals experience discomfort and anomalous visual perceptual distortions when they observe patterns of stripes with particular spatial characteristics.

What is pattern glare?

The visual system evolved to analyse scenes from nature (figure 1). Natural scenes have a characteristic Fourier power spectrum in which the low spatial frequencies have more power and the high spatial frequencies less, according to a simple function of spatial frequency.¹

Figure 1: An image from nature

The most unnatural image is one in which all the contrast energy is concentrated in one orientation, and at a limited range of phases and spatial frequencies, such as the scene in figure 2.