The Advantages and Disadvantages of Both Edge-lit and Back-lit LED Panels

LED panels are commonly available on the market. These lights can be divided into two types based on their structural principle: edge-lit and back-lit. Although both work on the same principle: to produce luminous lighting by driving the power supply through voltage and current to the LED chips, they differ in their product structure, light form, and luminous principle. 

The edge-lit LED panels have a luminous structure, as shown in Figure 1. The LED chip emits light that enters the LGP from the side and is then released onto the surface of the lamp through the LGP.

Figure 1

There are several advantages from this for the edge-lit LED panels:               

1. The panel's height can be made smaller for a thinner look and lower packaging and transportation costs.

2. The LED chip is located close to the aluminium frame of the LED panel. The heat generated by the chips can easily reach the front of the lamp through the outer frame. The heat dissipation rate will be faster in areas with better air circulation.

3. The lamp will have a strong build due to the presence of LGP. The LGP supports the outer frame of the panel light, making the entire panel light more structurally stable.                                    

However, relatively speaking, there are some disadvantages: 

1. The energy efficiency is relatively low. It is not difficult to imagine that by placing the LED around the LGP and guiding the light downward, the export efficiency is lower than the straight-down type, resulting in the overall energy efficiency not being very high.

2. The price of an important part of the LGP is high, resulting in an increase in costs. According to the different lumen requirements of the lamp, different LGPs need to be configured, and the quality requirements are very high.

3. The reliability performance is relatively poor. Because the LGP, reflective ink and reflective film in the side luminous flat lamp are always at a relatively high temperature, it is easy to age and turn yellow, reducing the light rate and greatly reducing the LED panel's life.

For back-lit LED panels, the luminous structure is like the one below (Figure 2). The light emitted by the LED chip is emitted directly down through the astigmatism of a diffuser plate. 

Figure 2

Back-lit LED panel lights have greater advantages. 

1. High energy efficiency. The light emitted by the LED chips is directly irradiated through the diffusion plate, improving the luminaire system's energy efficiency.

2. The cost is lower. The cost of the LGP is eliminated, and the panel's cost is reduced.

3. The internal space is large, and the design is more flexible.

4. The weight of the back-lit LED panel is lighter, and fewer materials can improve the production capacity.

There are several problems with back-lit panels: 

1. The diffusion plate should not be too close to the LED chips to ensure uniformity and avoid glare. If it is too close, it may result in a luminous point being visible on the surface. Consequently, the height of the entire panel lamp should be high, increasing the thickness of the LED panel.                                                                                                     

2. The back-lit LED panel has a relatively large gap between the diffusion plate and the back cover. The lamp body is mainly supported by the corners of the lamp frame, making it less stable than the side-lit panel light. The diffusion plate and the back cover are not strong enough to withstand any extrusion, and the panel may get damaged easily during transportation if compressed.