LED Street Light Color Temperature Adjustment Method
Different color temperature of LED street light will give people different feelings in different light conditions. In the environment with low light condition, light of low color temperature will make people feel pleased and comfortable. However, light of high color temperature can make people feel gloomy, dim and cold. In the environment with strong light condition, light of low color temperature makes people feel stuffy; while light of high color temperature makes people feel comfortable and happy.
PWM dimming drive power solution is put into use in the new method of LED color temperature adjustment. The color temperature circuit is added to the back-end circuit. The color temperature adjustment circuit adopts PWM switch dimming method to adjust the ratio of the conduction time of the cool white LED array and the warm white LED array to realize the color temperature adjustment.
When the color temperature value is around 5000K, LED street light emits white light. When the color temperature is around 3000K, LED street light emits yellow light or warm white light, which is more suitable for roadway lighting than the white light with 5000K color temperature. That’s because the light of 5000K color temperature will make people feel very cold and dazzling visually, which will lead to excessive visual fatigue. Under this color temperature condition, people’s observation ability will also decline.
The color temperature is unit of measurement of the light color of the light source. When the radiation of absolute black body is exactly the same as the radiation of the light source in the visible region, the temperature of the black body at this time is the color temperature of the light source. The color temperature of light emitted by different light sources is different.
In the energy distribution of low color temperature light source, there is much red radiation. The emitted light is called “warm light”. In the energy distribution of high color temperature, there is much blue radiation. And the emitted light is called “cold light”. The color temperature value of medium color temperature is between 3000K to 6000K. People have no obvious visual psychological effect under the light of medium color temperature, so it is called “neutral” color temperature. The high color temperature value is more than 6000K. The light color is bluish, giving people a cool feeling. When the object is illuminated by a high color temperature light source, it will make people feel cold.
PWM dimming drive power solution is put into use in the new method of LED color temperature adjustment. The color temperature circuit is added to the back-end circuit. The color temperature adjustment circuit adopts PWM switch dimming method to adjust the ratio of the conduction time of the cool white LED array and the warm white LED array to realize the color temperature adjustment.
When the color temperature value is around 5000K, LED street light emits white light. When the color temperature is around 3000K, LED street light emits yellow light or warm white light, which is more suitable for roadway lighting than the white light with 5000K color temperature. That’s because the light of 5000K color temperature will make people feel very cold and dazzling visually, which will lead to excessive visual fatigue. Under this color temperature condition, people’s observation ability will also decline.
The color temperature is unit of measurement of the light color of the light source. When the radiation of absolute black body is exactly the same as the radiation of the light source in the visible region, the temperature of the black body at this time is the color temperature of the light source. The color temperature of light emitted by different light sources is different.
In the energy distribution of low color temperature light source, there is much red radiation. The emitted light is called “warm light”. In the energy distribution of high color temperature, there is much blue radiation. And the emitted light is called “cold light”. The color temperature value of medium color temperature is between 3000K to 6000K. People have no obvious visual psychological effect under the light of medium color temperature, so it is called “neutral” color temperature. The high color temperature value is more than 6000K. The light color is bluish, giving people a cool feeling. When the object is illuminated by a high color temperature light source, it will make people feel cold.