where it was converted into electrical impulses to stimulate the remaining healthy neurons in the retina. this information was then passed on to the optic nerve and the vision processing centres of the brain. on 2 january 2019, bvt released positive results from a set of trials on four australians using a new version of the device. older versions of the device were only designed to be used temporarily, but the new design allowed the technology to be used constantly, and for the first time outside the lab, even to be taken home. more implants are to be administered throughout 2019. according to fact sheets dated march, 2019, on bvt's website, they expect the device to obtain market approval in 3 to 5 years. dobelle eye similar in function to the harvard/mit device, except the stimulator chip sits in the primary visual cortex, rather than on the retina. many subjects have been implanted with a high success rate and limited negative effects. the project first began in 2002 and was still in the developmental phase, upon the death of dobelle, selling the eye for profit was ruled against in favor of donating it to a publicly funded research team. intracortical visual prosthesis the laboratory of neural prosthetics at illinois institute of technology (iit), chicago, started developing a visual prosthetic using intracortical electrode arrays in 2009. while similar in principle to the dobelle system, the use of intracortical electrodes allow for greatly increased spatial resolution in the stimulation signals (more electrodes per unit area). in addition, a wireless telemetry system is being developed to eliminate the need for transcranial wires. arrays of activated iridium oxide film (airof)-coated electrodes will be implanted in the visual cortex, located on the occipital lobe of the brain. external hardware will capture images, process them, and generate instructions which will then be transmitted to implanted circuitry via a telemetry link. the circuitry will decode the instructions and stimulate the electrodes, in turn stimulating the visual cortex. the group is developing a wearable external image capture and processing system to accompany the implanted circuitry. studies on animals and psychophysical studies on humans are being conducted to test the feasibility of a human volunteer implant. stephen macknik and susana martinez-conde at suny downstate medical center are also developing an intracortical visual prosthetic, called observe. the planned system will use an led array, a video camera, optogenetics, adeno-associated virus transfection, and eye tracking. components are currently being developed and tested in animals.