Title
An ambient light adaptive subretinal stimulator
Abstract
This paper presents a subretinal stimulator which is able to automatically adapt to varying ambient light levels. Stimulation timing and intensity are controlled using an input amplifier with an offset current cancellation circuitry to eliminate offset current imposed on the pixel amplifier for accurate stimulation control and optimized power consumption. In order to enable the chip to operate over a wide range of luminance conditions without manual tuning, automatic ambient light adaptation is required. Comparing the local photosensor output with a global luminance reference signal forms the basis of the adaptation mechanism. Global brightness information is obtained by logarithmic conversion of the summed photocurrents to generate a global luminance reference voltage. The chip has been realized in Austria Micro Systems 0.35 mum CMOS Opto technology.
Year
DOI
Venue
2009
10.1109/ESSCIRC.2009.5325980
Athens
Keywords
DocType
ISSN
cmos image sensors,biomedical electronics,brightness,eye,photodetectors,prosthetics,vision,austria micro systems cmos opto technology,ambient light adaptive subretinal stimulator,ambient light level,global brightness information,input amplifier,local photosensor output,luminance,offset current cancellation circuitry,optimized power consumption,photocurrents,pixel amplifier,stimulation intensity,stimulation timing,adders,chip,photoconductivity,light adaptation,pixel
Conference
1930-8833
ISBN
Citations 
PageRank 
978-1-4244-4354-3
1
0.49
References 
Authors
2
7
Name
Order
Citations
PageRank
Liu Liu1324.16
jurgen wunschmann210.49
Nasim Pour Aryan3477.67
amr zohny410.49
michael m j fischer510.49
steffen kibbel610.49
Albrecht Rothermel78117.91