| 摘要 |
Apparatus for generating electromagnetic radiation in which the radiation has both a first and a second utility. The electromagnetic radiation is modulated to produce electronically detectable variations to achieve the second utility, the variations not effecting the first utility. In one embodiment, the second utility is transmission of information. In this embodiment, the electromagnetic radiation is visible light in which the first utility is illumination and the second utility is the sending of information, the variations in the visible light being invisible to the human eye. In another aspect, the invention is a lamp for generating visible light to provide illumination and to transmit information to a receiver in which the variations in the light as a result of the information transmission are undetectable to the human eye. |
