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全彩LED顯示屏的最關(guān)鍵部件是LED燈珠。原因有三： 第一，LED是全彩屏整機(jī)中使用數(shù)量最多的關(guān)鍵器件，每平方米會(huì)使用幾千至幾萬(wàn)只LED; 第二，LED是決定整屏光學(xué)顯示性能的主體，直接影響觀眾對(duì)顯示屏的評(píng)價(jià); 第三，LED在顯示屏整體成本中所占比例最大，從30%至70%不等。 如何鑒別LED顯示屏燈珠優(yōu)劣 一、看焊點(diǎn)。正規(guī)的LED燈帶廠家生產(chǎn)的LED燈帶是采用SMT貼片工藝，用錫膏和回流焊工藝生產(chǎn)的 二、看FPC質(zhì)量。FPC分敷銅...

封裝工藝說(shuō)明 1.芯片檢驗(yàn) 鏡檢：材料表面是否有機(jī)械損傷及麻點(diǎn)麻坑（lockhill） 芯片尺寸及電極大小是否符合工藝要求，電極圖案是否完整。 2.擴(kuò)片 由于LED芯片在劃片后依然排列緊密間距很?。s0.1mm），不利于后工序的操作。我們采用擴(kuò)片機(jī)對(duì)黏結(jié)芯片的膜進(jìn)行擴(kuò)張，是LED芯片的間距拉伸到約0.6mm。也可以采用手工擴(kuò)張，但很容易造成芯片掉落浪費(fèi)等不良問(wèn)題。 3.點(diǎn)膠 在LED支架的相應(yīng)位置點(diǎn)上銀膠或絕緣膠。（對(duì)于GaAs、SiC導(dǎo)電襯底，具有背面電...

SMD LED 就是表面貼裝發(fā)光二極管的意思，SMD貼片有助于生產(chǎn)效率提高。 以及不同設(shè)施應(yīng)用。是一種固態(tài)的半導(dǎo)體器件，它可以直接把電轉(zhuǎn)化為光。它的電壓為1.9-3.2V，紅光、黃光電壓最低，LED的心臟是一個(gè)半導(dǎo)體的晶片，晶片的一端附在一個(gè)支架上，一端是負(fù)極，另一端連接電源的正極，使整個(gè)晶片被環(huán)氧樹(shù)脂封裝起來(lái)。半導(dǎo)體晶片由兩部分組成，一部分是P型半導(dǎo)體，在它里面空穴占主導(dǎo)地位，另一端是N型半導(dǎo)體，在這邊主要是電子。但這兩種半導(dǎo)體連接起來(lái)的時(shí)候，...

PN結(jié)的端電壓構(gòu)成一定勢(shì)壘，當(dāng)加正向偏置電壓時(shí)勢(shì)壘下降，P區(qū)和N區(qū)的多數(shù)載流子向?qū)Ψ綌U(kuò)散。由于電子遷移率比空穴遷移率大得多，所以會(huì)出現(xiàn)大量電子向P區(qū)擴(kuò)散，構(gòu)成對(duì)P區(qū)少數(shù)載流子的注入。這些電子與價(jià)帶上的空穴復(fù)合，復(fù)合時(shí)得到的能量以光能的形式釋放出去。這就是PN結(jié)發(fā)光的原理。 特點(diǎn) 1. 電壓：LED燈珠使用低壓電源，供電電壓在 2-4V之間，根據(jù)產(chǎn)品不同而異，所以驅(qū)動(dòng)它的是一個(gè)比高壓電源；更安全的電源，特別適用于公共場(chǎng)所； 2.電流：工作電流在0—15m...

LED beauty instrument, LED beauty mask principle In recent years, some merchants have claimed that LED red and blue light has improved the skin, and developed an LED beauty instrument. Users can calm their emotions and focus wh...

Light has a particularly important position on the growth and development of plants, which affects almost all stages of growth of plants. The effect of light on plants is mainly manifested in two aspects: One is to provide radia...

1. Perspective The angle of view of the LED display is determined by the angle of view of the LED bead. At present, most of the outdoor display screens use a horizontal viewing angle of 100°; a vertical viewing angle of 50°; an e...

Violet, also called UV (Ultra Violet), is the shortest wavelength of light in visible light. Some bands of violet light are often called "black light" because the light in these bands is invisible to the human eye. UV vi...

Nowadays, the SMD LED market is highly sought after. In addition to the state's promotion of energy conservation, it is possible to draw conclusions and conclude that the top ten advantages make the LED market hot: First, the...

First, the common precautions in the use of SMD LED : 1, welding conditions Reflow soldering: Preheat at 150 ° C for 2 minutes, and heat once at 240 ° C for 5 seconds. Soldering iron soldering: Use a temperature-controlled s...