How to strengthen the protection level of LED indoor display?

At present, SMD display screen used in the market has become a mainstream mature product, among which the indoor LED small space display screen is widely used in conference room, court, Public Security Bureau, procuratorate, command center, TV station, etc. at the same time, channel sales mode has been widely used in shopping malls, restaurants, schools, public construction and other places. So how to strengthen the protection level of LED indoor display?

For the general LED indoor display screen, when the product is delivered, it is in the state of zero fault, but after a period of use, the light will be broken and the column will be on, and the light will be dropped due to the accidental collision; In the installation site environment, sometimes there are unforeseen or unsatisfactory scenarios. For example, the temperature difference of air conditioner tuyere short-distance direct blowing causes large area of bad points, or the site environment is too humid, resulting in the bad point rate of the screen rising day by day.

For the indoor small space industry which has passed the inspection for half a year, how to solve the display screen problems caused by water vapor, dust, bump, and broken lamp rate, and improve the product quality and reduce the burden and cost of after-sales service are the problems that the manufacturers of LED indoor display screen want to solve.

 

Figure 1. Bad short circuit and column lighting of LED display

Therefore, in order to effectively solve the mentioned problems, the so-called surface coating solution is produced.

This solution is based on the current indoor surface mounted LED display, and the equipment can be directly combined with the existing SMT surface mount production line, as shown in Figure 2.

 

Figure 2. Schematic diagram of surface coating equipment (lamp surface)

The process is to cover the surface of the lamp board made by SMT surface mounting process after 72 hours of aging process to form a so-called protective layer, which can wrap the conductive pins and isolate the influence of moisture and moisture, as shown in Figure 3.

For the LED display products with general protection level of IP40 (ipxx, front x dust-proof and rear x waterproof), it has the advantages of effectively improving the protection level of LED light surface, providing anti-collision effect, avoiding the occurrence of lamp dropping and reducing the whole screen bad point rate (PPM). At present, this kind of solution has met the market demand, and the production is mature, and it will not excessively increase the overall cost burden.

In addition, the protection process on the back of the printed circuit board (PCB) maintains the three proofing paint protection process used in the past (as shown in Figure 4). Generally, the protection grade of the back of the circuit board can be improved by coating the surface of the integrated circuit (IC) to form a protective layer, so as to avoid the failure of the integrated circuit components of the driving circuit.

For the indoor use of LED display module, such a solution can effectively prevent the occurrence of failure points caused by moisture and dust by wrapping the exposed electrical conductive pins. At the same time, it can provide protection against collision. At present, the surface coating solutions on the market include gob display screen, AOB display screen, etc.