How much influence of heat dissipation on LED lights

Due to the global energy shortage and environmental pollution, LED display has a broad application space with its energy-saving and environmental protection characteristics. The application of LED luminous products in the lighting field is attracting the attention of the world. Generally speaking, the stability and quality of LED lamps are crucial to the heat dissipation of the lamp body. At present, the heat dissipation of high brightness LED lamps in the market is often natural, and the effect is not ideal. The LED lamp made by LED light source is composed of LED, heat dissipation structure, driver and lens. Therefore, heat dissipation is also an important part. If the LED cannot dissipate heat well, its life will be affected.

Influence of heat on high brightness LED

The heat is concentrated in a very small chip, and the temperature of the chip increases, which causes the non-uniform distribution of thermal stress, the luminous efficiency of the chip and the phosphor lasing efficiency to decrease; When the temperature exceeds a certain value, the device failure rate increases exponentially. Statistics show that the reliability decreases by 10% when the temperature of the element increases by 2 ℃. When multiple LEDs are densely arranged to form a white light lighting system, the problem of heat dissipation is more serious. Solving the problem of heat management has become a prerequisite for the application of high brightness LED.

Relationship between chip size and heat dissipation

The most direct way to improve the brightness of the power LED display screen is to increase the input power. In order to prevent the saturation of the active layer, the size of the p-n junction must be increased accordingly; Increasing the input power will inevitably increase the junction temperature, thereby reducing the quantum efficiency. The improvement of single tube power depends on the device's ability to derive heat from the p-n junction. Under the same chip material, structure, packaging process, current density on the chip and the same heat dissipation conditions, the junction temperature will rise continuously if the chip size is increased separately.