13-03-2017, 03:26 PM
An artificial retina that uses thin-film transistors powered by a wireless power source. It has been found that the illumination profile can be correctly detected as the output voltage profile even if operated using an unstable power source generated by inductive coupling, diode bridge and Zener diodes. This means the feasibility of implanting the artificial retina into the human eyeballs. Artificial retinas have been ardently desired to regain the sense of sight for the visually impaired.
Artificial retinas with external chambers, stimulus electrodes and three-dimensional LSIs have been actively developed for patients suffering from retinitis pigmentosa and age-related macular degeneration. In these cases, photodiodes and electronic circuits replace the deteriorated photo receptor cells. Implant methods can be classified into four types: epiretinal implant, subretinal implant, suprachoroidal stimulation, and transretinal stimulation. Among these implant methods, the epiretinal implant has characteristics that the resolution of the image may be high because the stimulus signal can be led directly to neuronal cells and that the living retinas are not seriously damaged. In our research, we have proposed an artificial retina using thin-film transistors (TFT) that can be fabricated on transparent and flexible substrates.