Communicating With Light: From Telephony to Cell Phones
A CIPT Lab Exercise in Modern Physics
This series of six activities introduces the physics of transmitting "voice" information using electromagnetic signals or light. Students explore how light can be modulated to encode voice information using a simple version of Bell's original photophone. They observe the decrease of the intensity of open- air signals by increasing the distance between source and receiver, and learn the advantage of using materials with different indices of refraction to manipulate and guide light signals. Students are introduced to the concept of bandwidth by using two different wavelengths of light to send two signals at the same time. Finally, students explore how optical signals are manipulated in a photonic chip.
Physics, Grades 9-12
Two 80-minutes periods allows time for each of the module's 6 distinct activities to be perormed.
Price: No Charge
Jim Overhiser, Cornell University, Ithaca, NY
Luat Vuong, SUNY, Queens College, Flushing, NY