How many lumens is sunlight?

Lumen is a unit of luminous flux, and the relationship with light intensity (Candela) is more complex.

The general parameter for evaluating this type is illuminance.

Illuminance can be measured directly with an illuminometer. Its unit is Lux lx.

In general, when the luminous flux of an object uniformly irradiated by light is 1 lumen on an area of 1 square meter, its illuminance is 1 lux.
In summer, the sun's illumination during the day is 10 to the power of 9.

And by the way, say something. You can't use leds to simulate sunlight on solar cells.

Solar radiation is a form of thermal radiation, and light is complex. For solar cells, from the infrared region to the ultraviolet region play a more or less positive or negative role. LED currently generally uses phosphor excited to produce mixed white light. It's basically a cold light source. Therefore, it cannot be used as a simulation of the sun.

Xenon lamps are generally used.

 

Extended information:

 

Luminous flux and lumens:

 

The light energy emitted by the light source radiates in all directions, and for the light energy passing through a certain area in a unit time, it is called the radiant energy flux through this area. Each color of light has a different frequency.

 

The sensitivity of the eye to each color of light is also different, even if the radiant energy flux of each color of light is equal, in the vision can not produce the same degree of brightness, in each color of light, yellow, green light can arouse the largest bright feeling.

 

If the green light is used as the level, so that its luminous flux is equal to the radiant energy flux, then for other colors of light, the ability to arouse bright sensation is smaller than that of green light, and the luminous flux is smaller than that of radiant energy flux.

The unit of luminous flux is lumen, which is the transliteration of English lumen, abbreviated as lm.

 

At the freezing temperature of platinum, the absolute blackbody radiates 1lm from an area of 5.305*10³cm². In order to show the relationship between luminous intensity and luminous flux, the luminous flux emitted by a point source with luminous intensity of 1 candela in unit solid Angle (1 sphericity) is 1 lumen. The luminous flux of a 40W fluorescent lamp is about 2100 lumens.

 

Illumination and Lux:

 

Illuminance can be measured directly with an illuminometer. The unit of illumination is lux, which is a transliteration of English lux, and can also be written as lx.

 

When the luminous flux of an object uniformly irradiated by light is 1 lumen on an area of 1 square meter, its illuminance is 1 lux.

 

Sometimes in order to make full use of the light source, a reflecting device is often attached to the light source, so that more luminous flux can be obtained in some directions to increase the illuminance on the illuminated surface. For example, car headlights, flashlights, photography lights, etc.