百科知识视频之煎蛋小学堂53 现代灯泡原理

Light bulbs used to be simple,just run a bunch of electrical current through a thin wire.until it heats up enough to start glowing,Bare filament electric lamps were first demonstrated around 1800 by Humphry Davy,and the glass bulb was added later,to keep oxygen away from the wire,so it could glow for a long time without actually burning up.

早期灯泡的原理十分简单 把电流通过一段细金属丝里 直到它热到开始发光就行 1800年前后，汉弗里 戴维发明了一种灯丝裸露的灯泡 随后玻璃灯管被整合进了设计 为灯丝隔绝氧气 让灯丝更耐用而不会很快烧化

So the incandescent light bulb is 19th century technology ,and by now there is a blinding array of electric lamps,halogen light bulbs,fluorescents,mercury and sodium vapor lamps,LEDs and so on.Each one makes its own clever use of physics to achieve the life goal of a light bulb:converting electrical current into visible light.

这么说来白炽灯泡其实是19世纪的技术 而现在，市场上可供选择的灯泡琳琅满目 卤素灯。荧光灯，水银或钠蒸汽灯，发光二极管等等 每一种都巧妙应用了物理原理 来完成电灯的任务：把电流转化为可见光 .

Here's how they work:halogen bulbs have the same tungsten metal filament,as typical incandescent light bulbs,but they contain a little bit of halogen based gas in the bulb as well,The chemistry of the halogen gas,allows it to capture stray tungsten atoms that evaporate off the filament and shepherd them back to where they belong,which both prolongs the life of the filament,as well as keeps the insides of the bulbs clean and clear.

我们接下来说说它们的原理 卤素灯和白炽灯一样 有一根钨制的金属灯丝 但是它们的灯泡中还有一些卤元素的气体化合物 这些化合物的化学性质 使得他们可以捕捉从灯丝蒸发的钨原子 再把它们重新附着在灯丝上 这样既延长了灯丝的寿命 还能让灯泡干净透亮.

Fluorescent bulbs are basically gas-filled tubes,with electrodes as both ends,Electrical current flows one electrode to another,and when the electrons that make up the current bump into mercury atoms in the gas,the energy of the collision makes the atoms get"excited"that's the technical term,and the atoms then emit visible and ultraviolet light.

荧光灯本质上就是填充了气体的管子 两端接上电极 电流在两个电极之间流动 当电流中的电子与气体中的汞原子碰撞时 碰撞的能量让原子“兴奋”起来(激发)术语就是这个?之后原子会发出可见光和紫外线.

The white coating on the inside of the glass,absorbs the ultraviolet light and re-emits it as more visible light,The process is called "fluorescence"and is the namesake of the bulb.Because the coating stops the UV light,it also keeps the bulb from giving you cancer,Unless that's what you want in which case you use a tanning bulb with a different kind of coating.

灯管内部的白色涂层 会吸收紫外线在放出更多的可见光 这个过程叫做“荧光” 荧光灯就是因此命名 因为灯管里的涂层吸收了紫外线 使用这种灯泡没有致癌风险 如果你想做死的话 那你需要去照有另一种涂层的美黑灯

Vapor Lamps:Sodium, mercury and metal-halide vapor lamps,which are commonly used for lighting streets warehouse, gymnasiums and another large areas,are also tubes that run electrical current through a gas.The gas itself emits mainly visible light.so these bulbs don't need a fluorescent coating.

蒸气灯：钠，水银或金属卤化物蒸汽灯 经常被用于马路，仓库，体育场和其他大型场地的照明 原理也是将电流通入充满气体的灯管中 填充的气体主要发出可见光 所以这些灯泡不需要荧光涂层

Light Emitting Diodes(LEDs):Finally,LEDSs are also like fluorescent light bulbs,except replace the gas with a tiny crystal of semi-conducting gallium,and throw away the bulb,So not like fluorescent bulbs.

发光二极管:发光二极管跟荧光灯其实很像 只不过把气体换成一小块半导体晶体镓 再把玻璃灯管扔掉 其实跟荧光灯不同的?

But seriously,the semiconductor has two layers,one of which provides excited electrons with lots of energy,while the other provides a place for the electrons to go and "relax",That IS the technical term,all you need is an electrical current to transport the electrons from the party side,to the SPA side,where they release the energy of their excitement as light,Viola! A light emitting diode!Perfect for human parties!

实际上，半导体由两层组成 一层富含充满能量的激发态(兴奋)电子 另一层电子“放松”下来 这个也是术语来的(回到基态) 电流把激发态电子送到二极管的另一端 在这里电子由激发态跃迁回基态，能量以光子散发出来 铛铛!发光二极管!拿来给人类开派对再合适不过呢!