luminous efficacy

Luminous efficacy of a light source may be defined in two ways.

See luminous efficacy for an efficiency chart comparing various technologies.

See the table in the luminous efficacy article.

Luminous efficacy is a measure of how well a light source produces visible light.

A similar chart in the article on luminous efficacy compares a broader array of light sources to one another.

Luminous efficacy of a source is a property of the source as a whole.

In comparison with incandescent light bulbs, neon lamps have much higher luminous efficacy.

The luminous efficacy of radiation is then dimensionless.

For a fixed power and life, the luminous efficacy of all incandescent lamps is greatest at a particular design voltage.

Several key factors that play among these different methods, include color stability, color rendering capability, and luminous efficacy.

Lamps designed for different voltages have different luminous efficacy.

Luminous efficacy of radiation measures the fraction of electromagnetic power which is useful for lighting.

The primary objectives of CFL design are high luminous efficacy and durability.

The units of luminous efficacy are "lumens per watt" (lpw).

Later models were able to eliminate the cooling fan and improve luminous efficacy to 100 lumens per watt.

The luminous efficacy of a source is a measure of the efficiency with which the source provides visible light from electricity.

The luminous efficacy of lamps is the number of lumens produced for each watt of electrical power used.

Direct sunlight has a luminous efficacy of about 93 lumens per watt of radiant flux.

The ratio of the total luminous flux to the radiant flux is called the luminous efficacy.

It is also sometimes referred to as the wall-plug luminous efficacy or simply wall-plug efficacy.

However the light output is reported as proportional to , and the luminous efficacy proportional to .

Luminous efficacy is the measure of how much light is produced versus how much energy is consumed.

Mercury vapor lamps are more energy efficient than incandescent and most fluorescent lights, with luminous efficacies of 35 to 65 lumens/watt.

Since the decrease in light output will exceed the decrease in power drawn, the energy efficiency - luminous efficacy - of the lighting will drop.

Most LEDs have a higher luminous efficacy than halogen lights, but poorly designed driving electronics can negate the advantage.