A low pressure mercury-vapor gas-discharge lamp that uses fluorescence to produce visible light. The glass tube with phosphor deposited on its glass wall is filled with mercury vapor. A high voltage is applied across each end of the lamp, causing an electric current in the gas. The current excites the mercury vapor which produces ultraviolet (UV) light When the UV photons hit the phosphor coating on the glass wall, the phosphor absorbs the UV photons and then emits photons as light in the visible region. Fluorescent lighting requires the use of mercury, a hazardous material, and requires that fluorescent lamps be disposed of separately as hazardous waste.
Internet of Things (IoT)
A network of physical objects that contain embedded technology to sense, interact, and communicate within their physical environment. Although “Internet” is part of the name, the network could also be a private or closed network. An example of how the IoT might work within the lighting world is through smart lights, which have the ability to communicate wirelessly with a wider network, that can sense the presence of humans through sensors such as IR detectors, RFID tags, and cameras, and adjust the lighting accordingly with no human intervention. The resulting cost savings in energy, as well as a performance boost through adjusting light color temperature, will hopefully more than offset the march towards Big Brother-type surveillance.