The Study of Bi-Phasic Current Stimulus Circuit for Retinal Prosthesis

• Main Authors: Zhi-Ren wang, 王志仁
• Other Authors: Jih-Fu Tu
• Format: Others
• Language: zh-TW
• Published: 2008
• Online Access: http://ndltd.ncl.edu.tw/handle/46520162679876580712

碩士 === 聖約翰科技大學 === 自動化及機電整合研究所 === 96 === Eyes are the most important for the human’s sense organ, and it is important way to obtain the external information source and view, too. If we lose vision will bring more inconvenience for living. Many research groups hope to resume vision for the lost visual person. Especially, degeneration of photoreceptor cells is to cause blind. The mainly reason is Age-related (Macular Degeneration) and pigment retinitis (Retinitis Pigmetosa). Now, the medical science and technology are improved, there are appearances of retina prosthesis. The technology is to implant electrode eye-chip into the retina, effectively stimulus bipolar cell or Ganglion cells, and continually transmission the visual signal to the eye, then to achieve and recover the vision. There are two kinds of mainly electricity implanting techniques: Sub-retina electrode stimulus, and Epi-retina electrode stimulus.. In this thesis, we focus on the solution of structure and the circuits of the direction epi-retina, in which is combination of four parts: camera, wireless transmitting, retinal chip, microstimulating electrodes. The active of this artificial eye as a camera, a light beams into regulator and modulating, then transmitting by wireless, and the signal transmit into eyeball via demodulator, stimulus circuit produce appropriate current stimulus remain retinal cells. The most construction of this thesis is to add one inverter, which can enable positive and negative waveform more symmetry. The allover of circuit includes: digital and analog converter, Active Feedback Current Mirror, demultiplexer, two-way control circuit, etc.. The simulation result sufficient the maximum current value of 600μA at 10kΩ.