Electrical potential difference, which is commonly expressed as (VA − VB). Voltage is conceptualized as the electrical driving force that drives a conventional electric current in the direction A to B [..]

Light emitted from the luminaire directly into the sky which causes artificial sky glow and generally represents wasted energy.  Uplight is a component of the new TM-15-07based BUG rating system, whic [..]

The length of time an asset or device can be used without major refurbishing. In lighting, the useful life of lamps is typically stated at 70% of initial lumens since it is difficult to perceive this [..]

A measure of luminaire efficiency that focuses on the ability of the luminaire system to transfer heat from sensitive components, such asLEDs, to the outside environment. High levels of thermal effici [..]

Monochromatic vision in low light levels, which is produced by rod cells.

Electronic components and systems based on the use of semiconductors rather than vacuum tubes. Common types of solid state components include integrated circuits, liquid-crystal displays, and LEDs.

Photoreceptor cells in the retina of the eye that can function in low light levels, and which are primarily responsible for night vision.

A material used to mechanically support and electrically connect electronic components using conductive pathways, or traces, etched from copper sheets laminated onto a non-conductive substrate. Common [..]

Power over Ethernet or PoE technology describes a system to pass electrical power safely, along with data, on Ethernet cabling.

Vision under well-lit conditions, mediated primarily by cone cells, which allows color perception. Photopic vision is the basis for most commonly-accepted lighting metrics, including those published b [..]