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What is the conversion factor from lux to watts per square meter (W/m2)?

The conversion factor from lux to watts per square meter (W/m2) is 1 lux 1 watt per square meter.


What does LUX stand for?

The lux is the SI unit of illuminance, and is equal to 1 lumen per square meter.


How many lux are in a lumen?

Lux and lumen are both units related to light, but they measure different aspects. Lumen measures the total quantity of visible light emitted by a source, while lux measures illuminance, or how much light falls on a surface area. Specifically, 1 lux is equal to 1 lumen per square meter. Therefore, the number of lux in a lumen depends on the area over which the light is distributed.


How do you calculate a lux level in a room?

Light Level or Illuminance, is the total luminous flux incident on a surface, per unit area. The work plane is where the most important tasks in the room or space are performed.Measuring Units Light Level - IlluminanceIllumenance is measured in foot candles (ftcd, fc, fcd) (or lux in the metric SI system). A foot candle is actually one lumen of light density per square foot, one lux is one lumen per square meter. 1 lux = 0.0929 foot candle = 1 lumen /sq meter = 0.0001 phot1 ftcd = 1 lux / 10.7521 lumen/sq ft = 1 foot candle = 1x104 lux = 1 phot


How many joules in one lux?

Lux is a unit of illuminance that measures luminous flux per unit area, equivalent to one lumen per square meter. Joules, on the other hand, are a unit of energy. Since lux measures light intensity rather than energy, there is no direct conversion between lux and joules. The relationship between them depends on factors like the light source's efficiency and the duration of exposure.


How much does one lumen of light per square meter Define?

One lumen per square meter, also known as a lux, is a measure of illuminance that quantifies how much light is received on a surface. It represents the intensity of light that is distributed over a given area. Specifically, one lux is equivalent to one lumen of light spread evenly over one square meter of that surface. This measurement is commonly used to assess lighting levels in various environments.


What are the features of lux?

Lux is a unit of measurement for illuminance, representing the amount of light that falls on a surface per unit area. It is defined as one lumen per square meter. Key features of lux include its direct correlation with human visual perception, as higher lux levels indicate brighter light conditions. Additionally, lux is often used in various applications such as photography, interior design, and horticulture to ensure optimal lighting conditions.


How can you calculate the lux level from light fixture?

To calculate the lux level from a light fixture, you first need to determine the total luminous flux (measured in lumens) emitted by the fixture. Then, measure the area (in square meters) over which the light is distributed. The lux level can be calculated using the formula: Lux = Lumens / Area (m²). This gives you the illuminance in lux at the specified area illuminated by the fixture.


How many candelas equals 1 lux?

They really aren't equal because they measure two different things. However, they are related to each other.The Candela is the measure of the luminous intensity of a light source. A higher Candela number means a brighter light. Lux is a measurement of light density and means lumens per square meter. Again, a greater number of lux means that the surface being illuminated by the light is is receiving more light per square meter.The formula for calculating the conversion of candelas to lux is E = I/(D*D) where E is the Illuminance of the the surface in lumens per square meter (lux), I is the Intensity of the the light source in Candelas and of course (D*D) is the square of the distance from the light source in meters.Therefore 1 Candela will illuminate a surface with 1 Lux only at one meter from a light source. At different distances it will illuminate to different densities of light.For example: Solving for E, that same one candela light source would only read 1/4 lux at two meters [ 1/(2*2)] and 1/16 lux at four meters [1/(4*4)].If you know the lux at a given distance in meters from the light source you can solve for I and it will give you the intensity of the light in Candelas. From that you can calculate the intensity of the light.For example: Solving for I, multiply the lux times the square of the distance in meters and you will have the intensity of the light source in Candelas.So a reading of 8 lux at a distance of 3 meters would mean that the light source has an intensity of 8*3*3 or 72 candelas.


How many 40-watt fluorescent lights can produce 1000 lux?

To achieve 1000 lux, you would need approximately 6-7 40-watt fluorescent lights per square meter. Lux is a measure of illuminance, so the number of lights required can vary depending on factors such as the height of the lights and the reflectivity of the surfaces in the room.


How do you measure light intensity and what tools or methods are commonly used for this purpose?

Light intensity is measured using a device called a light meter, which detects the amount of light in a given area. Common methods include using a digital light meter, a lux meter, or a spectrophotometer to measure light intensity in units such as lux or lumens.


How do you find out lumen from lux?

There's not a direct conversion, but both are based on the candela, a unit of luminous intensity. There is a nice explanation of the difference between lumens and lux at http://en.wikipedia.org/wiki/Lumen_(unit).Lumens is the total amount of light a light source (a light bulb, for instance) throws in all directions. Lux (lumens per square meter) can measure how intense light from that light source is when looking toward it from a certain distance. Lux depends greatly on how far away you are from a light source. At any given instant, light is thrown from the source in a perfect sphere.If you are trying to calculate how many lumens your light bulb shines and you have a light meter that gives you lux, point your meter at the light, then take your lux multiply by 12.57 (pi times 4). Then, multiply this by the distance of your light meter from the light bulb (in meters) squared. That will give you the lumens of the light bulb. In equation form, where lm is lumens, r is your distance from the light source, and pi is (come on) about 3.14, lux=lm/(pi*4*(r^2)), or lm=lux*pi*4*(r^2). The (pi*4*(r^2)) part is used to calculate the surface area of a sphere around the light source.Note: this calculation does not account for reflected light, and will only work on an exposed light bulb. Lights housed in a reflective cone (like in a flashlight) are designed to project light in one direction and (within the spot where light is projected) will have a lux much higher at any given distance than if the light bulb wasn't housed in a cone.AnswerA lux is a special name given to a lumen per square metre. To convert lux to lumens, you need to multiply the illuminance (light arriving) on a surface, in lux, by the area of that surface, in square metres.