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Photovoltaic retinal prosthesis with high pixel density

A Corrigendum to this article was published on 23 November 2012

This article has been updated


Retinal degenerative diseases lead to blindness due to loss of the ‘image capturing’ photoreceptors, while neurons in the ‘image-processing’ inner retinal layers are relatively well preserved. Electronic retinal prostheses seek to restore sight by electrically stimulating the surviving neurons. Most implants are powered through inductive coils, requiring complex surgical methods to implant the coil-decoder-cable-array systems that deliver energy to stimulating electrodes via intraocular cables. We present a photovoltaic subretinal prosthesis, in which silicon photodiodes in each pixel receive power and data directly through pulsed near-infrared illumination and electrically stimulate neurons. Stimulation is produced in normal and degenerate rat retinas, with pulse durations of 0.5–4 ms, and threshold peak irradiances of 0.2–10 mW mm−2, two orders of magnitude below the ocular safety limit. Neural responses were elicited by illuminating a single 70 µm bipolar pixel, demonstrating the possibility of a fully integrated photovoltaic retinal prosthesis with high pixel density.

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Figure 1: Simplified system diagram.
Figure 2: Subretinal photodiode arrays.
Figure 3: In vitro electrophysiology.
Figure 4: Stimulation of healthy retina.
Figure 5: Stimulation of degenerate retina and strength-duration data.
Figure 6: Pillar arrays for improved proximity.

Change history

  • 16 November 2012

    A relevant publication on the topic of the flexible substrate concept applied to a retinal implant should have been cited in this Article. The publication is by Dinyari, R., Loudin, J. D., Huie, P., Palanker, D. & Peumans, P. and is entitled "A Curvable silicon retinal implant" published in International Electron Devices Meeting (IEDM) (IEEE International, 2009). It is now cited as reference 39 in the Article. Additionally, Fig. S4a in the Supplementary Information of the Article is reproduced from the same new reference, with permission from IEEE. These revisions have been made in HTML and PDF versions of the Article, and PDF version of the Supplementary Information.


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The authors thank Optobionics, especially G. McLean, for providing the ASR samples, and P. Peumans and R. Dinyari from the Electrical Engineering Department at Stanford University for providing a sample of the flexible silicon grid36 for tests of its flexibility in a porcine eye. We also thank A.M. Litke, S. Kachiguine, A. Grillo and W. Dabrowski for the development of the 512-electrode recording system, and M. Krause for his help with retinal preparations. The authors thank M.F. Marmor, M.S. Blumenkranz, R. Gariano and S. Sanislo from the Department of Ophthalmology at Stanford for productive discussions regarding implant design and surgical procedures. Thanks also go to S. Cogan at EIC Labs for fabrication advice and for iridium oxide electrode deposition, M. McCall at the University of Louisville for critical manuscript reading, and M. Pardue at Emory University for advice on subretinal implantations into RCS rats. Funding was provided by the National Institutes of Health (grant no. R01-EY-018608), the Air Force Office of Scientific Research (grant FA9550-04) and a Stanford Bio-X IIP grant. K.M. was supported by an SU2P fellowship as part of an RCUK Science Bridges award. J.L. was supported in part by the National Science Foundation Graduate Research Fellowship programme. A.S. was supported in part by a Burroughs Welcome Fund Career Award at the Scientific Interface.

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Authors and Affiliations



J.L. and D.P. jointly conceived and designed the pulsed-NIR photovoltaic retinal prosthesis system, and the three-diode pixel devices. K.M., T.K. and J.H. led the fabrication team of L.W. and L.G., with L.W. performing most of the fabrication steps that produced the implant device. A.S. and D.P. conceived the electrophysiology experiments, which were carried out by K.M., J.L., G.G. and R.S. under the guidance of A.S. Data analysis was performed by K.M. and G.G. with direction from A.S. The subretinal implantations and histological analysis was performed by P.H. J.L. wrote the first draft of the paper, with K.M., A.S. and D.P. contributing several sections and extensive edits. The project was organized and coordinated by D.P.

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Correspondence to James Loudin.

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Mathieson, K., Loudin, J., Goetz, G. et al. Photovoltaic retinal prosthesis with high pixel density. Nature Photon 6, 391–397 (2012).

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