COB encapsulation LED display quality and developing difficulty

Board encapsulation ( 板上芯片) Is a more than LED chip installed directly on the heat dissipation PCB substrate structure of direct heat conduction. COB packaging set the upstream chip technology, display technology, in the middle encapsulation technology and from so strong color in COB packaging need to understand, and downstream enterprises in close cooperation to push COBLED display large-scale application. COB packaging display module diagram as shown in the above, as a kind of COB integration encapsulation of LED display modules, positive for the LED module pixels, for at the bottom of the driver IC, finally pushes COB joining together to design the size of the LED display module display. COB theoretical advantages: 1, design, research and development: not a single lamp body diameter, could theoretically be more small; 2, technology process, reduce support cost and simplify the manufacturing process, thermal resistance, reduce the chip to realize high density packaging; 3, engineering installation: look from the application side, COB LED display module can be applied to display party manufacturers to provide more convenient and fast installation efficiency. 4, product characteristics: ( 1) Ultra-thin: according to the actual needs of customers, the thickness from 0. 4 - 1. At least 2 mm thickness of the PCB, make weight reduced to 1/3 of the original traditional products, can significantly reduce the structure for the customer, transportation, and engineering cost. ( 2) Anti-collision compressive: COB products are directly to the LED chips encapsulation inside the concave lamp of PCB, and then encapsulated with epoxy resin adhesive curing, lamp bump into spherical surface, smooth and solid, resistance to wear. ( 3) Big: perspective is greater than 175 degrees, close to 180 degrees, and has more excellent optical diffuse color into light effect. ( 4) Heat dissipation ability: COB products is to encapsulate the lamp on the PCB board, copper foil fast will wick on the PCB quantity of heat, and the copper foil thickness of the PCB board has strict technical requirements, combined with heavy gold craft, almost will not result in a serious light attenuation. So few dead lamp, greatly extend the life span of the LED display. ( 5) Wear-resisting, easy to clean, smooth surface and hard, bump wear resistance; No mask, dust or cloth to clean with water. ( 6) All-weather fine features: using triple inoculation, waterproof, moisture, corrosion, dust, static, oxidation, uv effect is outstanding; Meet the all-weather conditions, when it's minus thirty degrees to 80 degrees centigrade temperature environment can be normal use. It is these reasons, COB packaging technology in the field of display be pushed to the front desk. Current COB technical problem: the COB accumulation and workmanship details need to be updated in the industry, is also facing some technical problems. 1, the encapsulation of a passing rate is not high, low contrast and high maintenance cost; 2, the color uniformity than using spectral color separation of SMD components after patch display. 3, existing COB encapsulation, still use the formal chip, need solid crystal, wire craft, so many problems of welding line segment and the process difficulty is inversely proportional to the bonding pad area. 4, manufacturing costs, caused by defective rate is high, the manufacturing cost far more than SMD small spacing. Based on the above reasons, although the current COB technology has obtained certain breakthrough in the field of display, but doesn't mean the SMD technology from declining, in 1 point spacing. 0 mm above areas, SMD packaging technology, with its mature and stable product performance, a wide range of market practice and perfect the security system installation and maintenance of dominant role, user and market direction in the selection of the most suitable. Gradually as COB product technology and market demand of further evolution, 0 point spacing. 5毫米~ 1。 0 mm on the interval, the large-scale application of COB encapsulation technology will reflect its technical advantage and value, to borrow the industry a word to say: 'COB packaging is 1. 0 mm and below point spacing tailor-made '. Source: leds