Bremen 2001 – scientific programme

Parts | Days | Selection | Search | Downloads | Help

DD: Didaktik der Physik

DD 7: Posterausstellung

DD 7.16: Poster

Thursday, March 22, 2001, 11:15–12:30, Hinteres Foyer

An Examination of Optical Response of LED in Applied Electrical Signals — •Spyros Louvros¹, Stauros Kotsopoulos², George Economou¹, and Dimitrios Zevgolis¹ — ¹Physics Dept. University of Patras, Greece — ²Wireless Telecommunications Lab. Dept. of Electrical and Computer Eng. University of Patras, Greece

Semiconductor devices have been used extensively in optoelectronics and communications. Lately semiconductor lasers have been proved to be the most promising devices for conversion of electrical-to-optical signals in optical communication networks. However light emitting diodes (LED) are the counterparts of electrical-to-optical conversion with moderate efficiency in bandwidth and bit rates compared to semiconductor lasers. Considering though the cost efficiency in an integrated network, LED is still superior. Hence it is worthwhile to examine the behavior of LED in order to use it as a cheap solution for electrical-to-optical conversion in moderate and short distances optical communication networks. This paper presents an examination of the optical response of LED in several applied electrical signals. The optical-to-electrical current ratio is used as the parameter of evaluation. This ratio represents the possible maximum bit rate for data transmission using LED and is proved to depend on the frequency of the applied signal. Most of the electrical signals are digital modulated carriers and they contain infinite harmonics according to Fourier analysis. This ratio is used as the criterion for the applied electrical signal with the higher bit rate for transmission in a communication network.