First trials and future technologies for artificial retinas

While outer retinal diseases such as age-related macular degeneration and retinitis pigmentosa principally result in degradation of the photoreceptor cell layer in the macula and peripheral retina, respectively, the remaining retinal cell layers are often substantially spared, both anatomically and functionally. This observation led the Company to begin development of novel microphotodiode-based devices that could be implanted within the retina to replace the function of damaged retinal photoreceptor cells. The Company´s Artificial Silicon Retina implants are semiconductor-based microphotodiode array devices small enough to be implanted in the subretinal space within the retina (between the outer and inner layers of the retina). These devices are capable of generating electrical signals similar to those produced by healthy photoreceptor cells. Individual microphotodiode pixels are 20 μm×20 μm with 9 μm×9 μm electrodes separated from adjacent pixels by 10 μm channel stops. Pixel density is on the order of 1100 pixels/mm². The ASR is approximately 2 mm diameter and less than 50 μm thick