White light in the sun actually includes seven colors of light: red, orange, yellow, green, cyan, blue, and violet. Among them, _ color light has the lowest color temperature.

Red

For blackbody-based light, blue is "hotter" than red, and red is actually a "cooler" color. This is different from our traditional understanding. Everyone associates blue with "cold colors" and red with "warm colors." This traditional concept actually evolved from other aspects. Cooler water and ice look blue, while fire and heated metals have a reddish hue. On the contrary, this just proves that red is the "coldest" color of all visible light - red is the first color emitted as the temperature of metal increases. Observe ordinary incandescent light bulbs. The orange light emitted by incandescent light bulbs lasts throughout their lives. The moment the filament of the incandescent bulb fuses, the light emitted is obviously bluish. At the moment of fusion, the filament is much hotter than before, and the light on the glass of the bulb is The scorch marks are proof.

Informally, "color temperature" can also represent "white balance". Please note that color temperature only involves one variable (units in thermodynamic temperature scale K), while white balance involves two at the same time (red value, blue value).

In the field of photography, another quantity that expresses color temperature is called mired (Mired, inverse color temperature, using the reciprocal of color temperature to mark the unit of temperature). A very simple set of formulas can convert between color temperature and mired. (For the conversion formula and the reason for using mired, please refer to the mired entry)

The application name of light color describes warm light. The color temperature of warm light is below 3300K. Warm light is similar to incandescent lamps and has a red light component. More can give people a feeling of warmth, health and comfort. Suitable for families, residences, dormitories, hotels and other places or places with relatively low temperatures. Cold white light is also called neutral color. Its color temperature is between 3300K and 5300K. Neutral color makes people feel happy, comfortable and peaceful because of the soft light. Suitable for shops, hospitals, offices, hotels, restaurants, waiting rooms and other places. Cold color light is also called daylight color. Its color temperature is above 5300K. The light source is close to natural light. It has a bright feeling and makes people concentrate. It is suitable for offices, conference rooms, classrooms, drawing rooms, design rooms, library reading rooms, exhibition windows and other places.