The Architecture Design And Electromagnetic And Thermal Modeling Of A Retinal Prosthesis To Benefit The Visually Impaired
DOWNLOAD
Download The Architecture Design And Electromagnetic And Thermal Modeling Of A Retinal Prosthesis To Benefit The Visually Impaired PDF/ePub or read online books in Mobi eBooks. Click Download or Read Online button to get The Architecture Design And Electromagnetic And Thermal Modeling Of A Retinal Prosthesis To Benefit The Visually Impaired book now. This website allows unlimited access to, at the time of writing, more than 1.5 million titles, including hundreds of thousands of titles in various foreign languages. If the content not found or just blank you must refresh this page
The Architecture Design And Electromagnetic And Thermal Modeling Of A Retinal Prosthesis To Benefit The Visually Impaired
DOWNLOAD
Author : Stephen Christopher DeMarco
language : en
Publisher:
Release Date : 2003
The Architecture Design And Electromagnetic And Thermal Modeling Of A Retinal Prosthesis To Benefit The Visually Impaired written by Stephen Christopher DeMarco and has been published by this book supported file pdf, txt, epub, kindle and other format this book has been release on 2003 with categories.
Keywords: Retinal stimulator microchip, Visual Prosthesis, Retinal prosthesis.
The Architecture Design And Electromagnetic And Thermal Modeling Of A Retinal Prosthesis To Benefit The Visually Impaired
DOWNLOAD
Author :
language : en
Publisher:
Release Date : 2003
The Architecture Design And Electromagnetic And Thermal Modeling Of A Retinal Prosthesis To Benefit The Visually Impaired written by and has been published by this book supported file pdf, txt, epub, kindle and other format this book has been release on 2003 with categories.
This dissertation describes the design and study of a retinal prosthesis for individuals who have suffered loss of vision from degeneration of the outer retina. Retinitis pigmentosa and age-related macular degeneration lead to blindness through progressive loss of retinal photoreceptors. Experiments reveal that direct electrical stimulation of remaining ganglion cells in degenerate retina elicits visual percepts in blind RP/AMD patients. This motivates research toward the development of a retinal prosthesis system involving an implantable stimulator microchip to compensate the defective photoreceptors. Many prostheses do not reside fully inside the body, but consist of an implantable stimulation unit and an external unit. This underscores a need in the retinal prosthesis to deliver power and support high-speed bi-directional communication with the implant wirelessly. The current progress in the types of non-invasive connections to bio-implants is reviewed as it relates to the power and communication needs of prostheses. The extraocular unit is a hardware-reconfigurable system based on FPGA technology which produces real-time instructions for the implantable micro-stimulator IC. The current retinal stimulator IC is designed to provide electrical stimulation to the remaining ganglion cells of post-degenerative retina. Also described is a design technique to significantly reduce the on-chip area of the stimulus circuits. This yields more output channels per chip area, thereby raising the stimulation resolution. Temperature elevation in the eye and head tissues associated with the retinal prosthesis is studied. A high resolution 2D human head and eye model is developed at 0.25mm spatial resolution with associated dielectric and thermal properties suitable for numerical simulations. The Finite Difference Time domain method (FDTD) with material independent absorbing boundary conditions is used to predict the specific absorption rate (SAR) induced from electromagnetic expo.
Implantable Devices For A Retinal Prosthesis Design And Electromagnetic And Thermal Effects
DOWNLOAD
Author :
language : en
Publisher:
Release Date : 2004
Implantable Devices For A Retinal Prosthesis Design And Electromagnetic And Thermal Effects written by and has been published by this book supported file pdf, txt, epub, kindle and other format this book has been release on 2004 with categories.
A retinal prosthesis, wherein electrical stimulation is provided to the retina of a person inflicted with outer retinal degenerative diseases such as Retinitis Pigmentosa and Age-related Macular degeneration, has been clinically tested and has succeeded in providing limited vision; such as shape recognition. It is hoped that an increased electrode count will improve visual acuity. The retinal prosthesis considered in this work is a dual-unit system with an external (outside the human body) unit and an internal (inside the body) unit with a wireless link for power and data transfer between them. Such a system poses possible health risks due to the incident electromagnetic energy of the wireless link and the power dissipated by the internal components, particularly the processing chip which drives the electrodes responsible for eliciting a neural response from the retina. Tissue damage via heating is one the primary concerns for such a system making it necessary to obtain via simulation and in-vivo and in-vitro experiments, accurate estimates of thermal elevation due to the operation of the such devices. In this work, numerical methods have been developed to compute temperature increases and electromagnetic effects due to the prosthesis components in anatomically correct human head models. The explicit and the Alternating-Direction Implicit (ADI) Finite-Difference Time-Domain (FDTD) have been used. Further, a hybrid explicit-ADI method was developed for the heat equation which provided simulation speedup of more than 10x over conventional methods for the models considered. FDTD methods were employed to compute the induced current densities and Specific Absorption Rate (SAR) in the human head due the inductive link comprising the primary coil (external) and a secondary coil (internal). Different orientations of the primary coil were considered in a frequency range of 1 MHz-20 MHz to provide guidelines for choosing eventual frequency and power parameters to conform to i.
Using Simulation To Enhance Design And Application Of Retinal Prostheses
DOWNLOAD
Author : George Nicholas Scarlatis
language : en
Publisher:
Release Date : 2006
Using Simulation To Enhance Design And Application Of Retinal Prostheses written by George Nicholas Scarlatis and has been published by this book supported file pdf, txt, epub, kindle and other format this book has been release on 2006 with categories.
Dissertation Abstracts International
DOWNLOAD
Author :
language : en
Publisher:
Release Date : 2003
Dissertation Abstracts International written by and has been published by this book supported file pdf, txt, epub, kindle and other format this book has been release on 2003 with Dissertations, Academic categories.
American Doctoral Dissertations
DOWNLOAD
Author :
language : en
Publisher:
Release Date : 2002
American Doctoral Dissertations written by and has been published by this book supported file pdf, txt, epub, kindle and other format this book has been release on 2002 with Dissertation abstracts categories.
Assistive Technology For Visually Impaired And Blind People
DOWNLOAD
Author : Marion Hersh
language : en
Publisher: Springer Science & Business Media
Release Date : 2010-05-12
Assistive Technology For Visually Impaired And Blind People written by Marion Hersh and has been published by Springer Science & Business Media this book supported file pdf, txt, epub, kindle and other format this book has been release on 2010-05-12 with Technology & Engineering categories.
Equal accessibility to public places and services is now required by law in many countries. For the vision-impaired, specialised technology often can provide a fuller enjoyment of the facilities of society, from large scale meetings and public entertainments to reading a book or making music. This volume explores the engineering and design principles and techniques used in assistive technology for blind and vision-impaired people. This book maintains the currency of knowledge for engineers and health workers who develop devices and services for people with sight loss, and is an excellent source of reference for students of assistive technology and rehabilitation.
Retinal Implant
DOWNLOAD
Author : Kuanfu Chen
language : en
Publisher:
Release Date : 2011
Retinal Implant written by Kuanfu Chen and has been published by this book supported file pdf, txt, epub, kindle and other format this book has been release on 2011 with categories.
Artificial Sight
DOWNLOAD
Author : Mark S. Humayun
language : en
Publisher: Springer Science & Business Media
Release Date : 2007-09-30
Artificial Sight written by Mark S. Humayun and has been published by Springer Science & Business Media this book supported file pdf, txt, epub, kindle and other format this book has been release on 2007-09-30 with Science categories.
This book describes advances in implantable neural stimulation technology to restore partial sight to people who are blind from retinal degnerative diseases such as age-related macular degeneration and retintis pigmentosa. Many scientific, engineering, and surgical challenges must be surmounted before widespread practical applications can be realized. The book summarizes the state of research and clinical practice in the field and reviews the current ideas and approaches of its leading researchers and practitioners.
Thermal Safety Of A Retinal Prosthesis
DOWNLOAD
Author : Nicholas Lachlan Opie
language : en
Publisher:
Release Date : 2011
Thermal Safety Of A Retinal Prosthesis written by Nicholas Lachlan Opie and has been published by this book supported file pdf, txt, epub, kindle and other format this book has been release on 2011 with Artificial vision categories.