Luminous efficacy
Luminous efficacy is a measure of how well a light source produces visible light. It is the ratio of luminous flux to power. Depending on context, the power can be either the radiant flux of the sourc...
Luminous efficacy - Wikipedia
A Nanophotonic Comeback For Incandescent Bulbs?
Researchers combine the warm look of traditional light bulbs with 21st-century energy efficiency. Incandescent lighting and its warm, familiar glow is well over a century old yet survives virtually un...