unit of light flux. One lumen per square meter is one lux. One lumen per square foot is one foot-candle. Lux is the illuminance equal to one lumen per square meter.
Amount of light emitted by a 1-candela source passing through a specified area in space.
The amount of light cast upon 1 square foot of the inner surface of a hollow sphere of 1-foot radius with an international candle in its center.
A measurement of light brightness or intensity.
As used in reference to flashlights, it refers to the total amount of light radiated by the bare lamp, the LED, or the flashlight. Because this measurement does not consider the focusing efficiency of the reflector, it does not indicate how "bright" the focused beam will appear. A flood lamp with a very wide dim appearing pattern can have the same lumen rating as a very tightly focused intensely bright spot lamp assembly. Lumen ratings cannot be converted to beam candlepower.
SI unit for luminous flux.
A lumen (abbreviated as lm) is a unit that measures the visible power output of a light. While watts measure the power the bulb needs, lumens measure the visible light that the bulb generates.
Total light output of source.
Unit of measure for the flow of light; expresses the total quantity of light given off by a source regardless of direction. Defined as the amount of light falling on a surface of one square foot, every point of which is one foot away from a one-candlepower source.
Quantity of light that shines on one square foot of area from a distance of one inch.
A measure of light output from a source.
The hollow center of a cylindrical organ or tissue, such as that of a fallopian tube or a blood vessel. Adjective: luminal.
The quantitative measure of a lampsâ€(tm)s brightness. A 75 Watt incandescent bulb has 1,200 lumens, whereas a 18 Watt compact fluorescent bulb has 1,100 lumens.
Measurement of "candle power" or light output, a unit of light falling on a surface.
A measurement of light indicated by the amount of light radiated by one candela light source
a unit of light flux visible to the human eye
a measurement unit of illumination
a measure of how much light energy a bulb emits
a measure of light emitted from a fixture
a measure of the projector brightness
a unit of light output from a lamp, measured in foot-candles
The flux on one square foot of a sphere, one foot in radius, with a light source of one candle at the center that radiates uniformly in all directions.
The amount of light that is spread over a square foot of surface by one candle when all parts of the surface are exactly one foot from the one candle light source.
Unit of measure representing the total amount of light flux (energy) in any particular situation, e.g., from a lamp, through an aperture, etc.
a unit of measurement of the rate at which a lamp produces light. A lamp's light output rating expresses the total amount of light emitted in all directions per unit time. Ratings of initial light output provided by manufacturers express the total light output after 100 hours of operation.
Lumen is a measure of brightness often associated with the amount of light a projector is capable of.
lm]. A light intensity produced by the luminosity of 1 candela in one radian of a solid angle.
A unit of light power from a light source: the rate at which light falls on one square foot of surface area one foot away from a light source on one candlepower or on candela.
A unit of luminous flux equal to the light emitted in a unit solid angle by a uniform point source of one candle intensity.
The unit of measurement defining the output of a lamp. Could be said to measure a volume of light.
the hollow area within a tube.
The unit of measure for light output of a projector.
unit of luminous flux. One lumen equals 1.471m of radiant power at 555nm
A unit of measurement of light. 1 foot-candle falling on 1 square foot of area.
A lumen is a measurement of light. The higher the lumen count, the brighter the projection.
The unit of illumination on a surface. One lumen is the light of one candle power on each square foot of a surface of a sphere at a radius of one foot from the light source. See also ANSI Lumens.
Measure of amount of light emitted (one lumen is the amount of light from one candle one foot away)
The unit of illumination on a screen or other surface.
The space in the interior of a hollow organ.
a unit of measurement quantifying the amount of light emitted from a light source.
The measure of luminous flux (the rate at which light pulses are emitted or received). For instance, one candela of light covering a square foot of surface. See FOOTLAMBERT.
A measure of the luminous flux or quantity of light emitted by a source. For example, a dinner candle provides about 12 lumens. A 60-watt Soft White incandescent lamp provides about 840 lumens.
Lumen: A measurement of light. The most reliable ratings are expressed in ANSI Lumens. The higher the lumen count the brighter the projection.
A measurement of light output; refers to the amount of light emitted by one candle that falls on one square foot of surface located at a distance of one foot from the candle.
the measurement of a light's output.
is a measurement of light which indicates the amount of light radiated by a one candela light source.
A unit of light measurement, the amount of visible light that comes to the eye from a surface. In the special case of Dark Adaptation of the Eye, luminances of less than about 0.034 cd/m squared are the lowest measured light level detectable to the human eye. (cd/m squared means: Candela per square meter.)
A measurement of the amount of visible light energy that comes from a light source.
The unit of light quantity or output. One lumen is the amount of light striking a surface 1 sq ft (9.3 dm) in area, with a light density of 1 footcandle. Thus, 1 lumen equals 1 footcandle per square foot (9.3 dm).
Unit of luminous flux used to describe a quantity of light emitted by a source or received by a surface.
a unit of light given off by a light source. Lumen is the measurement used to compare the levels of illumination provided by different light sources. Energy Services Energy Systems/Technologies
A measure of a lamps light output.
Measurement of the Output of light from a Lamp.
A unit of luminous flux. The lumen is equal to the luminous flux radiated into a unit solid angle (steradian) from a small source having a luminous intensity of one candle. An ideal source possessing an intensity of one candle in every direction would radiate a total of 4 pi lumens. "Lumen" is a Latin word for light.
A unit of light flow, or luminous flux. The lumen rating of a lamp is a measure of the total light output of the lamp.
A unit used to measure the brightness of a light source. The more lumens produced per watt of power supplied, the more efficient a light source is. See Also: Wattage
A measure of the amount of light available from a light source equivalent to the light emitted by one candle.
Unit of luminous flux; the flux emitted within a unit solid angle by a point source with a uniform luminous intensity of one candela. One footcandle is one lumen per square foot. One lux is one lumen per square meter.
A unit of luminous flux; overall light output; quantity of light, expressed in lumens. For example, a dinner candle provides about 12 lumens and a 60 watt soft white incandescent lamp provides about 840 lumens.
The basic unit of measurement for light. One lumen per square foot equals one foot candle.
A measurement of light output from a lamp, tube, or bulb.
The International Standard for measuring light intensity. MB or Megabyte - A unit of measure for data. One Megabyte equals 1024 Kilobytes.
A measurement of quantity of light taken at the source of the light. Lumens per square foot are foot-candles.
The unit of measure for the light energy which flows in air. The total light output from electric sources is expressed in lumens. A uniform source of one candlepower placed in a sphere emits 12.57 lumens or mean spherical candela equals to 12.57 lumens.
Measurement of light. It is the amount of light that falls on a unit area at unit distance from a source of one footcandle (fc). One footcandle is one lumen per square foot.
The unit of measurement for the amount of light emitted by a lamp. One lumen per square foot is one footcandle.
The basic unit of measurement for light. A dinner candle shines at about 12 lumens. A 60-watt Soft White bulb is much more powerful: 855 lumens. If a uniform point source of 1 candela is at the center of a sphere of 1-foot radius which has an opening of 1 square foot area at its surface, the quantity of light that passes through is called a lumen. The sphere has a total surface area of 12.57 square feet. Since, by definition, a lumen flows to each square foot of surface area, a uniform point of 1 candela produces 12.57 lumens. The general term applied to families of smaller diameter fluorescent lamps, some of which have built in ballasts and medium screw bases for easy replacement of incandescent lamps.
The unit of luminous flux.
A Lumen is a quantity of light, the same kind of unit as a watt, but measured in such a way that takes into account the sensitivity of the eye. If you are looking at the specification of a light source Lumens are the measured as the entire output, no matter which direction the light is going in.
A standard international unit of luminous flux or quantity of light. The unit of the time rate of flow of light (luminous energy) equal to the energy emitted though a unit solid angle (one steradian) from a uniform point source of one candela (ASAE EP344.2 Dec99). Some examples: a dinner candle provides about 12 lumens while a 60-watt soft white incandescent bulb provides 840 lumens.
A unit of illumination; a measurement of light output. One lumen is equal to the light emitted by one candle that falls on one square foot of surface located one foot away from the candle.
The unit that expresses the total quantity of light given off by a source, regardless of direction. A lumen is defined as the amount of light falling on a surface of one square foot, every point of which is one foot away from a source of one candlepower. A uniform source of one candlepower placed in a sphere emits 12.57 lumens, or mean spherical candela equals 12.57 lumens.
A unit of luminous flux, equal to the flux through a unit solid angle (steradian) from a uniform point source of 1 cd or 1 FC (foot candle) per sq. foot.
A unit of measure for the amount of light emitted by a source. 0.98 Ft-c (foot-candles) of light covering a surface of 1 square foot.
The quantity of luminous flux emitted within a unit solid angle (one steradian) by a point source with one candella intensity in all directions.
Luminous flux unit defined as total flux in a space angle of one steradin, emitted by a one candela source (one candela emits 4 or 12.57 lumens.)
The SI of luminous flux, used in describing a quantity of light emitted by a source or received by a surface. A small source which has a uniform luminous intensity of one candela emits a total of 4 lumens in all directions and emits one lumen within one solid angle.
An SI unit for measuring radiant flux. One lumen is produced per solid angle by a point source with one candela intensity.
The unit of measure for the amount of visible light emitted by a light source.
A unit of photometric power. The lumen is equal to the amount of photometric power radiated into a unit solid angle ( steradian) from a small source having a luminous intensity of one candela. Tungsten-filament light bulbs produces approximately 15 lumens per watt.
An empirical measure of the quantity of light. It is based upon the spectral sensitivity of the photosensors in the human eye under high (daytime) light levels. Photometrically it is the luminous flux emitted with a solid angle (1 steradian) by a point source having a uniform luminous intensity of 1 candela.
A measurement of light emitted by a light source at the point of emission.