The definition of lumen is visible light value of the light output, that is, the luminous flux, which reflects the luminous intensity of the unit solid angle. The luminous intensity is related to the sensitivity of the human eye, unit is candela. Luminous flux has different corresponding relationships with power at different wavelengths. 1W optical power of 650nm red light is approximately equal to 73 lumens, the most sensitive 550nm filter of the human eye, 1W optical power is approximately 683 lumens. By default, conversion ratio of white light power to luminous flux is 683, the candela unit defination is also 1/683 watts / sphericity, luminous flux refers to how bright the emitted light looks to you. If it is invisible light, the luminous flux is small even if the power is used, but it does not mean that it is inefficient. Some units use mw / W and some use lm / W.
What is the lumen effect?
The greater number of lumens of a luminaire, the brighter it is. Lumen value of a luminaire divided by the wattage is the efficiency of luminaire: The larger the lumens value/ watt (LM / W), the higher brightness of different luminaires at the same electrical power, that is, At the same brightness, the lower the input power of the high-efficiency lamps, the more power-saving. And we have been moving in this direction.
Therefore, it is more important to buy LED lamps to check out their lumens than wattage.
How to choose the right lumens?
Indoors, the normal artificial light has an intensity of 400 to 600 lumens. If it is sunny outdoors, the brightness will fluctuate within a large range. Brightness in the shade is 1,000 lumens, while in places with large areas such as highways, the brightness is 6000 lumens. Below 3500 lumens, our eyes feel comfortable. When the brightness of direct or reflected light reaches 4000 lumens, the human eye starts to struggle to receive light. When we try to look at these very bright areas, we only see white flashes, which is glare.
To determine the required lumens, we need to refer to the actual indoor lighting area, such as a 100 square foot living room that requires 10-20 feet of candles and will need 1000-2000 lumens. A 100-square-foot restaurant requires 30-40 feet of candles and 3000-4000 lumens.
Is there anything else you want to know about lumens? Maybe we can explore it.
