Home / LED Blog / LED Lights / As a cold light source, why does LED make lots of heat?

As a cold light source, why does LED make lots of heat?

Views:0     Author:Site Editor     Publish Time: 2021-05-24      Origin:Site

1.What is cold light source?

Cold light source is almost no infrared spectrum of light source, such as the more popular LED light source is a typical cold light source. The traditional incandescent lamp and halogen lamp are typical thermal light sources. The characteristic of cold light source is that it converts almost all other energy into visible light, and there is little light of other wavelengths, while thermal light source is different. Besides visible light, there is a large amount of infrared light, and a considerable part of the energy is converted into infrared light which has no contribution to lighting. The light from the hot light source plus the infrared filter should be almost the same as that from the cold light source, because the infrared light has been filtered out.


2. Why does LED light cause heat?

Energy is conserved, it will not be generated without reason, and it will not disappear without reason. LED lights start to work after the power is connected, because only about 30% of the electric energy is converted into light energy, so other energy can only be converted into heat energy. Because the chip size of LED lamp beads is very small, the heat is concentrated in a relatively small place. If the heat is not dissipated in time, the temperature will be particularly high, and the life of lamp beads will be affected. High quality LED lamp will install the lamp beads on the aluminum substrate, and large radiators will be installed behind the aluminum base plate, so that the heat emitted by the beads can be quickly and evenly dispersed. And then when human hands touch it, we can only feel warm but not been burned.


So now we know that the so-called cold light source actually is not cold. But why do we say that led cold light source is more energy-saving than incandescent lamp? In fact, it is more efficient to convert electric energy into light energy.


3. Heat dissipation of led

The heat dissipation of LED starts from the two aspects of LED chip heat dissipation and LED lamp heat dissipation before and after package. The heat dissipation of LED chip is mainly related to the substrate and circuit selection process. Because any LED can make light, the heat generated by LED chip is finally distributed into the air through the lamp shell. If the heat dissipation is not good, the thermal capacity of LED chip will be very small. If some heat is accumulated, the connection temperature of the chip will be increased rapidly. If the high temperature is long, the life will be shortened rapidly. But these heat must go through several ways to guide the chip to actually get out of the air. In particular, LED chips will generate heat from metal hot blocks, from solder to PCB on aluminum substrate, and then to aluminum radiator through thermal adhesive. Therefore, LED lighting includes both thermal diffusion and thermal diffusion. The cooling mode of LED enclosure depends on the power supply size and the use position. The main cooling methods are as follows:


·Aluminum hot pin: the most commonly used heat method, using aluminum hot pins as part of the shell to increase the cooling area.

·Heat conduction plastic shell: when the plastic shell is injected into molding, it is filled with heat conducting materials to improve the thermal conductivity and heat dissipation capacity of the plastic shell.

·Aerodynamics: making convection air with the shape of rattan is the cheapest way to heat.

·Fan: the lamp shell is a long-life high-efficiency fan, which can strengthen cooling, low cost and good effect. But it's very difficult to change the fan and it's not suitable for outdoor use. This design is rare.

·Heat exchanger: heat exchanger technology is used to induce heat in LED chip to the heat pin of the shell. Street lights and other large lighting is a typical design.

·Surface radiation heat treatment: the surface of the lamp shell is radiation heat dissipation treatment. The radiation heat dissipation coating of sishengweihua is applied to emit heat from the surface of the lamp shell.