Acceptance method of full color LED display screen

The acceptance of full-color LED display screen is probably from two aspects: screen appearance (visual inspection, hand feeling) and box (with the help of tools).

1、 Screen appearance inspection and detection method: visual inspection and hand feeling can preliminarily see whether there is a problem with the LED screen
1. Coating adhesion: there shall be no falling off (including intersection)
2. Whether the color is consistent or biased, or even not bright. No chromatic aberration (including no chromatic aberration with natural light) under the observation of gloss and sample; The coating surface shall be smooth, flat and uniform, and the surface shall not have the following defects: no dry back adhesion, particles, bottom leakage, pitting, blooming, wrinkling and mechanical damage;
3. Screen printing appearance: the screen printing content shall be clear, complete, uniform in color, and free of burrs, defects, tailing and pollution; The specific content, location, pattern and font size of all silk screen printing shall be described in detail by the corresponding drawings. The manufacturer shall silk screen printing in strict accordance with the drawing design requirements. 2、 LED display box inspection
Test method: actual test tools: vernier caliper, tape measure and level ruler.
Requirements: the inspector must inspect the incoming materials of the display box one by one in strict accordance with the designer’s drawings to check whether there are few or missing parts. The box inspection shall pay attention to the following problems:
1. The overall dimension deviation of LED box shall not be greater than 0.5mm, and the difference between the two diagonals shall not be greater than 1mm.
2. Check whether the burr is removed and whether the acute angle is blunt. Scraping and stabbing are not allowed.
3. All nuts and nut posts must be subject to thread back treatment to ensure that the screws can be locked smoothly.
4. Check whether the overall assembly requirements of the box are processed according to the drawings. All accessories (such as locks and hinges) must adopt existing standard parts, and their mechanical strength and sealing performance must be guaranteed during assembly.
5. All welding parts of the box must be welded firmly without false welding, missing welding and other phenomena. The welding points must be ground flat. The welds need to be scraped, and the treatment process must be strictly standard. Welds must be polished, sealed and waterproof, smooth and flat without acute angles.
6. After punching and welding of LED module holes, the flatness of the front side shall be ensured, the surrounding panels shall be free of warpage and deformation, and the flatness error shall be less than 1mm; The size of the positioning hole of the front panel of the box shall be strictly controlled, and the error of the hole size and hole distance shall be less than 0.1mm; The X and Y directions of the hole assembly axis shall be on the same straight line respectively, and the straight line shall be perpendicular to the edge of the box, and the perpendicularity shall be less than 1mm.
Attention shall be paid to the appearance of LED display screen without surface defects such as close-up adhesion, particles, bottom leakage and pockmarks. There shall be no details such as rough edges, defects, tailing and the position of silk screen. For the box, you need to watch the size of the box, the welding process, the compactness of each nut, etc. Only when every small detail is done carefully, can it be regarded as a truly qualified product.