摘要 |
Described are apparatus for transmitting light wave signals, the apparatus being capable of adjusting their signal strength to automatically adapt to changes in the ambient light conditions of their surrounding environment. In one embodiment, the apparatus for transmitting lightwave signals comprises (a) an emitter for sending a frequency modulated lightwave signal of variable intensity, (b) a light energy receiver for detecting a change in the level of surrounding ambient light energy and for producing a response to such change in proportion to the change detected, and (c) a controller for adjusting, directly or indirectly, the frequency modulated lightwave signal in response to the light energy receiver response to the change detected. Audio transmission systems employing apparatus of this invention are also described. |