Hi,
Free Space Optics (FSO) communications, also called Free Space Photonics (FSP) or Optical Wireless, refers to the transmission of modulated visible or infrared (IR) beams through the atmosphere to obtain optical communications. Like fiber, Free Space Optics (FSO) uses lasers to transmit data, but instead of enclosing the data stream in a glass fiber, it is transmitted through the air. Free Space Optics (FSO) transmits invisible, eye-safe light beams from one “telescope” to another using low power infrared lasers in the teraHertz spectrum. The beams of light in Free Space Optics (FSO) systems are transmitted by laser light focused on highly sensitive photon detector receivers. These receivers are telescopic lenses able to collect the photon stream and transmit digital data containing a mix of Internet messages, video images, radio signals or computer files.
Optical wireless communication -in the infrared and visible range – is an attractive solution, especially in environment settings where radio communication encounters difficulties. The Fraunhofer Heinrich Hertz Institute HHI applies modern transmission techniques that enable data-rates up to 1,25 Gbit/s. LED-lamps, normally used for lighting purposes, simultaneously transmit data, even when mobile terminals are not aligned with the access point.

Thanks,