What is Lumen?

Writer： admin Time：2021-02-26 21:11 Browse：℃

The so-called lumen simply refers to the brightness of a candle at a distance of one meter (1 meter = 1 meter). An ordinary 40 watt incandescent bulb has a luminous efficiency of about 10 lumens per watt, so it can emit 400 lumens of light. The 40 watt incandescent lamp has 340 lumens at 220 volts. Luminous flux is the ability to describe the visual response of light source radiation in unit time. The unit is lumen, also known as brightness. The unit of luminous flux of projector is ANSI lumen. ANSI lumen is the standard for measuring luminous flux of projector formulated by American National Institute for standardization. It measures the illuminance of each point on nine intersections of screen "field", multiplies the area, and then calculates the average value of nine points, which is the ANSI lumen of the projector. The higher the lumen value is, the brighter it is, and the higher the brightness is, there is no need to turn off the light during projection. ANSI is the abbreviation of American National Standards Institute。