4k light

the color temperature of the led lamp is 4K, which is cold white.

according to China's "national standard for lighting lamps":

27-4K is warm white.

4-57k is a confession.

6-7k is white.

8k is cold white.

the color temperature of the lights in shopping malls and hotels is basically about 4K .. 4 is officially called cold white, and 4-5 (neutral white) is good for home use.

Supplement:

Color temperature is a unit of measurement indicating the color components contained in light. Theoretically speaking, color temperature refers to the color of an absolute blackbody after it is heated from absolute zero (273℃). After being heated, the black body gradually turns from black to red, yellow and white, and finally emits blue light. When heated to a certain temperature.

the spectral components contained in the light emitted by a black body are called the color temperature at this temperature, and the unit of measurement is "k" (Kelvin). If the light emitted by a light source is the same as the spectral components contained in the light emitted by a black body at a certain temperature, it is called a certain K color temperature, for example, the color of the light emitted by a 1W bulb is the same as that of an absolute black body at 2527K, then the color temperature of the light emitted by this bulb is:

color temperature and brightness: under the irradiation of high color temperature light source, if the brightness is not high, it will give people a cold atmosphere; Under the irradiation of low color temperature light source, too high brightness will give people a sultry feeling. Comparison of light and color: When two kinds of light sources with large light color difference are used in the same space, the contrast will have a hierarchical effect. When the light and color contrast is large, the brightness level can be obtained at the same time.

For the problem of color temperature of extended materials

, you can have a detailed look at the Baidu Encyclopedia entry, color temperature:

<; 33K warm (reddish white) steady and warm

3-5K middle (white) refreshing

> 5K cool (blue white) cold

all belong to white, 27-4K belongs to warm white, 4-57k belongs to natural white, 6-7k belongs to positive white, and above 8k belongs to cold white.

LED is a light emitting diode, which is a solid semiconductor device that can convert electric energy into visible light, and it can directly convert electricity into light. The heart of LED is a semiconductor chip, one end of which is attached to a bracket, one end is a negative electrode, and the other end is connected to the positive electrode of power supply, so that the whole chip is encapsulated by epoxy resin.

a semiconductor wafer consists of two parts, one is a p-type semiconductor, in which holes are dominant, and the other is an n-type semiconductor, mainly electrons here. But when these two semiconductors are connected, a P-N junction is formed between them. When the current acts on the chip through the wire, the electrons will be pushed to the P region, where the electrons will recombine with holes, and then the energy will be emitted in the form of photons, which is the principle of LED light emission. The wavelength of light, that is, the color of light, is determined by the material forming the P-N junction.