JELE_V1_N1_RP4 S. Sankar Journal on Electronics Engineering 2249 – 0760 1 1 26 30 Light Emitting Diode, Touch Sensor, Single-Touch Screen, Multi-Touch Screen, Light Emitting Diode Communication Light Emitting Diodes (LEDs) are low cost electronic devices widely used for displays. One of LED properties, apart from the ability to emit light, is to operate as a photo sensor. Thus, a LED may be simultaneously used as a display element and as a sensing element. This characteristic may implement electronic displays with touch sensing capability. In this paper, the author describe the development of a display prototype that senses a finger touch and alters its operation. This operation may be extended to multi-touch sensing, boosting displays performance while keeping hardware requirements to the same level. It is worth mentioning that the sensing ability is provided by software, exploiting LED sensing capability, with the same hardware as this used for displaying purposes. The implication of this project is the ability to construct displays that their operation can be dynamically configured without any other hardware overhead or any additional cost. Also, the sensing capability of LEDs may be used to develop optical serial communication between two devices. Thus, LEDs may implement communication functions at a minimal cost and in cases where other technologies are expensive (infrared, bluetooth, etc). For example, the power light of a device may be used for maintenance reports or firmware update with the existing hardware. This experimentation has shown that LEDs are inexpensive elements that may offer interested advantages both for displaying and sensing purposes. September - November 2010 Copyright © 2010 i-manager publications. All rights reserved. i-manager Publications http://www.imanagerpublications.com/Article.aspx?ArticleId=1196