Frequently Used Words
FREQUENTLY USED WORDS
Some of the words you find on our site are obvious, and some, not so much. That's why we've created a handy glossary to clarify the more challenging terminology. Mesopic lumens anyone?
A diode of a semiconductor material, emitting light when a forward bias is applied.
First generation of energy-saving light bulbs, which last longer and use less energy than traditional light bulbs for the same level of intensity- they contain mercury -- which is a big problem. LED's save more energy, are less wasteful, and are not toxic to dispose of -- not to mention last up to 10 times longer.
Electric lamp that produces light by an electric arc through a gaseous mixture of vaporized mercury and metal halides (compounds of metals with bromine and iodine).
How much light a light source will generate. Light output is measured in lumens at the light source.
A quantitative measure of the ability of a light source to reveal the colors of various objects faithfully in comparison with an ideal or natural light source.
The temperature at which a black body would emit radiation of the same color as a given object.
The combination of photopic and scotopic vision in low but not dark lighting situations. What's photopic and scotopic? Look below!
Relating to or denoting vision in dim light, believed to involve chiefly the rods of the retina.
The vision of the eye under well-lit conditions. In humans and many other animals, photopic vision allows color perception, mediated by cone cells, and a significantly higher visual acuity and temporal resolution than available with scotopic vision.
A type of light measured in lumens generally detected by common light meters and accounts for part of the human eye’s perception of brightness or light levels.
Substance that exhibits the phenomenon of luminescence.
The ratio of scotopic to photopic lumens produced by a light source. An appropriate S/P ratio will offer a more comfortable atmosphere and better perceived brightness.
Complete lighting unit.
A tool that helps companies to understand the environmental impacts associated with their products, processes, and activities.
Corporate initiative to assess and take responsibility for the company’s effects on the environment and impact on social welfare.