Abstract
A prototype chip with 2×2 pixels for implanting in blind patients affected by outer retinal degeneration is presented in this paper. This visual prosthesis chip imitates the degenerated photoreceptor cells, senses the incident light and stimulates the remaining healthy layers of retina or optic nerve. Each pixel integrates photodiode and stimulus pulse generator, converting the illumination on the eyes into 3-bit resolution bi-phasic current pulses. On-chip charge cancellation modules are used to discharge each electrode site for tissue safety. The prototype chip is designed and fabricated in 0.18-μm N-well CMOS (complementary metal oxide semiconductor) 1P6M Mix-signal process, with a ±2.5 V dual voltage supply. The functionality of the fabricated chip is demonstrated on anesthetized rabbits. Neural responses in visual cortex are successfully evoked by the neuro-stimulus chip through an on-board trigger interface and flexible electrode.
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References
Hymen L. Epidemiology of eye diseases in the elderly. Eye, 1987, 1: 330–341
Margalit E, Maia M, Humayun M S, et al. Retinal prosthesis for the blind. Survey Ophthal, 2002, 47: 335–356
Humayun M S, Juan E D, Dagnelie G, et al. Visual perception elicited by electrical stimulation of the retina in blind humans. Arch Ophthal, 1996, 114: 40–46
Humayun M S, Juan E D, Weiland J, et al. Pattern electrical stimulation of the human retina. Vision Res, 1999, 2569-2576
Zrenner E. Will retinal implants restore vision? Science, 2002, 295: 1022–1025
Chow A Y, Pardue M T, Chow V Y, et al. Implantation of silicon chip microphotodiode arrays into the cat subretinal space. IEEE Trans Neural Syst Rehab Eng, 2001, 9: 86–95
Sivaprakasam M, Liu W, Humayun M S, et al. A variable range bi-phasic current stimulus driver circuitry for an implant-able retinal prosthetic device. IEEE J Solid-State Circ, 2005, 40: 763–771
Liu W, Vichienchom K, Clements M, et al. A neuro-stimulus chip with telemetry unit for retinal prosthesis device. IEEE J Solid-State Circ, 2000, 35: 1487–1690
DeMarco S C, Liu W, Singh P R, et al. An arbitrary waveform stimulus circuit for visual prostheses using a low-area multibias DAC. IEEE J Solid-State Circ, 2003, 38: 1679–1690
Theogarajan L S. A low-power fully implantable 15-channel retinal stimulator chip. IEEE J Solid-State Circ, 2008, 43: 2322–2337
Ortmanns M, Unger N, Rocke A, et al. A 0.1 mm2, digitally programmable nerve stimulation pad cell with high-voltage capability for a retinal implant. IEEE Int Solid-State Circ Confer, 2006, XLIX: 52–53
Tokuda T, Asano R, Ohta J. Retinal stimulation on rabbit using complementary metal oxide semiconductor based multichip flexible stimulator torward retinal prosthesis. Japan J Appl Phys, 2008, 47: 3220–3225
Kleinfelder S, Lim S, Gamal A E. A 100000 frames/s CMOS digital pixel sensor. IEEE J Solid-State Circ, 2001, 36: 2049–2059
Nakauchi K, Fujikado T, Kanda H. Threshold suprachoroidal-transretinal stimulation current resulting in retinal damage in rabbits. J Neur Eng, 2007, 4: S50–S57
Schlyter P. Radiometry and photometry in astronomy. http://en.wikipedia.org/wiki/Lux
Hirokazu S, Takashi F, Yasuo T, et al. Electrical stimulation with a needle-type electrode inserted into the optic nerve in rabbit Eyes. Japan J Ophthal, 2004, 48: 552–557
Keita M, Taiichiro W, Mitumasa K, et al. Evaluation of electrical simulus current applied to retina cells for retinal prosthesis. Japan J Appl Phys, 2006, 45: 3784–3788
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Zhang, X., Pei, W., Huang, B. et al. Implantable CMOS neuro-stimulus chip for visual prosthesis. Sci. China Inf. Sci. 54, 898–908 (2011). https://doi.org/10.1007/s11432-010-4175-6
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DOI: https://doi.org/10.1007/s11432-010-4175-6