Charles Leroy applied a static electric shock to a blind patient’s scalp, inducing a flamelike image in their visual cortex. Below is Leroy working on his machine.
Otfrid Foerster discovered that electrically stimulating a spot in the visual cortex results in the simulation of phosphenes, which are small dots in our vision. Below is an artist's rendition of the phosphene map.
Giles Brindley implanted 80 electrodes under a 52 year-old blind woman's scalp. Under stimulation, the woman ‘saw’ flashes of light. Although these flashes of light were relatively random, this visual impression laid the basis for bionic vision today.
Arman Tanguay and Noelle Stiles conducted the first experiment to implant a digital camera in an eye, replacing a dog's natural lens with a glass lens and a sensor.
The introduction of a 1,000-electrode implant allowed for blind volunteers to recognize faces and read half-inch type for the first time. The image below shows what an individual with a 1,000-electrode implant would see.
The Argus II Retinal Prosthesis System replaces the photoreceptors to aid the eye’s light gathering process. However, this system is bulky and produces low quality images. An image of the Argus II is seen below.