Infrared Communicator

 

Transmit sound by modulating infrared light.  The transmission can be interrupted by placing your hand in the slot provided.  The infrared light is visible by using a camera on a cell phone.

Fiber Optic Data Transmission

 

By the press of a button data is transferred from one point to another via fiber optic cable.  The  modulated laser is visible in a spot where the sheath has been removed.  The laser modulation can clearly be seen in the lower enlarged simulation of the fiber optic principle.