Second Sight — the developer of the first bionic eye to receive FDA approval in the US — is currently working on a firmware upgrade that gives users of the Argus II bionic eye better resolution, focus, and image zooming. The software update even provides users with color recognition, even though the original version of the device only provides black and white vision.
The Argus II, to give its proper classification, is a retinal prosthesis. Basically, patients undergo a four-hour operation to implant 60 electrodes into the macula — the central region of the retina that provides central and high-resolution vision. These electrodes are connected to an antenna, which connects via a wireless network to a special pair of spectacles that are equipped with a digital camera and a digital signal processor (DSP). The camera captures what the user is looking at, converts the image into signals that the brain will understand, and transmits them to the retinal implant. These signals stimulate the 60 electrodes in such a way as to produce electrical signals that can be understood by the brain.
As you can imagine, an array of 60 electrodes doesn’t provide a very high resolution (10×6!), but it’s a huge step up from complete blindness. as you can imagine, upgrading the retinal implant is rather hard — presumably, you’d have to spend a few hours digging it out (if that’s even possible), and then a few more hours replacing it. Furthermore, if Second Sight changes the hardware, it would need to be re-certified by the FDA, which could take years. A software update, however, doesn’t require FDA approval(though in the future, as implants become more invasive, that will probably change).