this invention is for directly modulating a beam of photons onto the retinas of patients who have extreme vision impairment or blindness . its purpose is to supply enough imaging energy to retinal prosthetics implanted in the eye which operate essentially by having light activating photoreceptors , or photoelectrical material . the invention provides sufficient light amplification and does it logarithmically . while it has sufficient output light power , the output light level still remains at a safe level . most preferred embodiments of this invention provide balanced biphasic stimulation with no net charge injection into the eye . both optical and electronic magnification for the image , as for example , using an optical zoom lens , is incorporated . otherwise , it would not be feasible to zoom in on items of particular interest or necessity . without proper adjustment , improper threshold amplitudes would obtain , as well as uncomfortable maximum thresholds . therefore , to adjust for these , a way of proper adjustment for the threshold amplitudes and maximum comfortable thresholds is provided . furthermore , to the extent that the individual stimulation sites in the retina give different color perceptions , upon stimulation , then colors of the viewed scene is correlated with specific stimulation sites to provide a certain amount of color vision .