Distance Filtering System for Retinal Implants

DESCRIPTION provided by applicant We propose to develop and evaluate the utility of a novel input camera system for retinal prosthetics that allows users to filter optical imagery based on distance from the observer We call this andquot depth filteringandquot which can be accomplished with a depth sensing stereoscopic camera system Retinal prostheses can restore partial vision to people blinded by outer retinal degenerative diseases such as Retinitis Pigmentosa RP or Macular Degeneration The Argus II Retinal Prosthesis System is intended to provide electrical stimulation of the retina to elicit visual perception in blind individuals with near total visionloss due to retinitis pigmentosa The implanted epiretinal array provides a x grid of electrodes Electrical pulses at these pixel sites stimulate the retinaandapos s remaining cells and result in the perception of patterns of light The current spatial resolution is only total pixels but the camera systems that provide image information to the prosthesis user transmit full resolution video information Information in the imagery consists of all visible items within the field of vie ranging for example from nearby obstacles to far away mountain scenery The lack of perceived spatial resolution makes it extremely difficult for prosthesis users to differentiate between important nearby elements within the scene and relatively unimportant distant elements of the scenery or vice versa An image capture and processing system is proposed that selectively removes elements in a viewed scene that are outside a user set depth range We hypothesize that system utility in important tasks such as people or object finding and mobility will be less burden some and performance improved by providing only relevant visual information to the wearer The proposed project seeks to develop and experiment with distance filtered optical imagery as an input modality to retinal implants Two prototype systems will be specified designed built and evaluated in Argus II patients In phase of the proposed project the image processing will be performed by a computer external to the Argus II system In phase a more powerful version of the next generation Argus II video processing unit capable of performing the image processing will be utilized This will be coupled with a new dual camera eyeglass assembly making the phase prototype fully integrated and ready for commercialization in the next generation Argus II system and possibly in other visual prosthesis systems and head mounted electronic low vision aids PUBLIC HEALTH RELEVANCE Retinal prostheses aim to help people who have lost their vision due to degenerative eye conditions such as retinitis pigmentosa to perceive shapes and movement to become more mobile or to perform other day to day activities The proposed project relates to the utilization of distance specific optical imaging as an input modality to a retinal prosthesis thus improving the prosthesis wearerandapos s understanding of the scene by removing unwanted irrelevant information