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The main aim of Artificial Vision is to restore some degree of sight to the profoundly blind (see "Who Benefits"). Since blindness can result from defects at many different points along the visual pathway, there are accordingly a wide variety of proposed models for an "Artificial Eye".

The earliest stage of visual processing is the transduction of light into electrical signals by the photoreceptors. If this is the only process that is interrupted in a blind individual, he or she may benefit from a Sub-Retinal Prosthesis, a device that is designed to replace only the photoreceptors in the retina.

If the transmission of a visual signal is interrupted before it gets to the ganglion cell layer, an Epi-Retinal Prosthesis can replace the lost functionality in the retina and communicate directly with the ganglion cells. These cells can then relay the signal to the rest of the central nervous system.

Another location in the visual pathway that is vulnerable to damage is the Optic Nerve. This bundle of cells serves as a transmission line from the eyes to the brain. If an individual has no functional ganglion cells, but has an intact Optic Nerve, it is possible to evoke the perception of light by stimulating these cells. However, if the Optic Nerve itself is damaged, the only possibility for restoring sight is to directly stimulate the visual cortex. Cortical Prostheses are designed specifically for this task.

Although the categories presented above account for most of the research in Artificial Vision, there are a few more exotic techniques being developed. One of these is the Biohybrid Implant, a device that incorporates living cells with man-made elements.

Regardless of the specific design, all of these devices are working towards the same goal: a permanent replacement for part of the human visual system. The ultimate form of any artificial visual aid employs a video camera that records the visual world and transmits this information in real-time to the upper-level visual processes. Although this is unlikely to mimic the detailed percepts obtained by the innate visual system, it should provide enough useful vision to perform every-day tasks such as navigation, recognition, and reading.