SMD (Surface Mount Device) is a surface-mount packaging technology that is currently quite mature in small-pitch LED displays. It involves packaging chips into individual LED beads, which are then mounted onto a PCB board. The pixel pitch is usually P0.9 and above; below P1.5, it is prone to LED failure. There are black edges between the LED beads, resulting in a noticeable grainy appearance when viewed from a close distance. However, it is easy to maintain, as individual LED beads can be replaced, and the technology is cost-effective due to economies of scale, making it suitable for conventional indoor and outdoor large-screen applications where cost-effectiveness is a priority.
COB (Chip-on-Board) is a chip-level direct packaging technology that bypasses the traditional LED bead structure, directly mounting the chips onto the circuit board, maximizing integration. It can achieve ultra-small pixel pitches below P0.9, resulting in a fine, grain-free image that is very comfortable to view from a close distance. It also offers strong heat dissipation, moisture and dust resistance, and is thin and space-saving. However, its drawbacks include high maintenance costs and a complex manufacturing process, leading to a higher price. It is suitable for high-end indoor applications such as conference rooms and command centers that demand high-precision image quality.
MIP (Micro LED Packaging) is a micro-LED packaging technology adapted for Micro LEDs. It involves packaging tiny LED chips into individual devices, which are then integrated onto a substrate. It can achieve ultra-small pixel pitches with display fineness close to COB, while ensuring image consistency through spectral and color separation. Structurally, it balances protection and maintainability, supporting the replacement of individual devices, and is compatible with existing SMD production lines. Its cost is lower than COB, and it is mainly used in professional applications requiring ultra-small pixel pitch and high-end Micro LED displays.
