Abstract: An apparatus to treat refractive error of the eye comprises one or more optics configured to project stimuli comprising out of focus images onto the peripheral retina outside the macula. While the stimuli can be configured in many ways, in some embodiments the stimuli are arranged to decrease interference with central vison such as macular vision. The stimuli can be out of focus images may comprise an amount of defocus within a range from about 3 Diopters (“D”) to about 6 D. In some embodiments, the brightness of the stimuli is greater than a brightness of background illumination by an appropriate amount such as at least 3 times the background brightness. In some embodiments, each of a plurality of stimuli comprises a spatial frequency distribution with an amplitude profile having spatial frequencies within a range from about range of 1×10?1 to 2.5×101 cycles per degree.