You have been misled about lightbulbs

关于灯泡，你一直被误导了

2026-07-30

There’s a story that goes something like this: In 1925, lightbulb manufacturers secretly colluded to standardize lifespans at 1,000 hours. They would test each other’s products to ensure compliance. This is true. At the time, many bulbs lasted longer than one thousand hours. This is true. Therefore, this was done so that people would always need to buy more light bulbs and increase their profits. This is wrong, but it’s the type of wrong that cites its sources and hides in the part you’d never think to fact-check: The assumption that a longer-lasting lightbulb is a good product. In truth, increasing the lifespan of a bulb makes it worse in every other way… but people think they want a long-lasting lightbulb: the purpose of standardizing was to avoid a race to the bottom.

流传着这样一个故事：1925年，灯泡制造商秘密串通，将灯泡寿命标准化为1000小时。他们会测试彼此的产品以确保合规。这是真的。当时，许多灯泡的寿命确实超过了1000小时。这也是真的。因此，人们认为这样做是为了让消费者不断购买新灯泡以增加利润。这种说法是错误的，但它错得很有“水平”——它引用了来源，并隐藏在你从未想过要去核实的部分：即“寿命更长的灯泡就是好产品”这一假设。事实上，延长灯泡寿命会使其在其他各方面表现更差……但人们总以为自己想要长寿命的灯泡：标准化的真正目的是为了避免恶性竞争。

An old-school lightbulb is a rather simple device: A thin tungsten wire (~20 μm) sealed inside a glass envelope to protect it from air. When current is applied, the wire gets white hot and starts glowing. The most important parameter of a lightbulb is how hot that wire gets: this controls the peak emission wavelength (color) and brightness of the lamp. Room temperature objects do emit light (this is how thermal cameras work), but it’s at the ~10 μm range instead of the 400 nm - 700 nm light that we can see. In order to put the emission peak in the visible spectrum, the filament would need to run at ~5700 °C … that is, the temperature of the sun. No metal can survive these conditions: Tungsten melts at “only” 3422 °C.

传统的白炽灯是一种相当简单的装置：一根细钨丝（约20微米）密封在玻璃罩内，以隔绝空气。当电流通过时，钨丝被加热到白炽状态并开始发光。灯泡最重要的参数是钨丝的温度：这决定了灯泡的峰值发射波长（颜色）和亮度。室温物体确实会发光（热成像仪就是利用这一点），但其波长在10微米左右，而非我们可见的400纳米至700纳米范围。为了使发射峰值处于可见光谱内，灯丝需要达到约5700°C的高温……也就是太阳表面的温度。没有任何金属能承受这种条件：钨的熔点“仅”为3422°C。

Filament materials: Since it has the highest melting point of any metal, tungsten is the obvious choice for filaments. However, the metal is quite brittle and drawing it into a wire isn’t easy. The first commercialized lamps used carbon filaments that were made by charring plant fibers. However, the carbon would evaporate at fairly modest temperatures ~2000 °C. Tantalum filaments were briefly produced during the 1900s, because the metal was easier to draw into a wire than tungsten. This resulted in the first lightbulbs that could actually be left on at night, although these were quickly replaced when tungsten manufacturing improved. There were also some experiments using zirconium dioxide ceramics, which become conductive when heated. These allowed lamps to operate in air (obviating the need for a vacuum pump or glass seals), but were limited by its melting point of 2,700 °C.

灯丝材料：由于钨拥有所有金属中最高的熔点，它是灯丝的不二之选。然而，这种金属非常脆，将其拉成细丝并不容易。最早商业化的灯泡使用的是通过碳化植物纤维制成的碳灯丝。但碳在约2000°C的较低温度下就会蒸发。20世纪初曾短暂生产过钽灯丝，因为钽比钨更容易拉成丝。这造就了第一批可以整夜开启的灯泡，尽管随着钨丝制造工艺的改进，它们很快就被淘汰了。此外，还有一些使用二氧化锆陶瓷的实验，这种材料在加热时会导电。它们允许灯泡在空气中工作（无需真空泵或玻璃密封），但受限于其2700°C的熔点。

Since any filament must run below its melting point, the peak emission is always deep in the infrared. This means that only the extreme high-energy edge of the spectrum is useful for illumination; a small increase in temperature will make a lamp orders of magnitude more efficient. Also, pushing the peak energy upwards allows the filament to produce shorter wavelengths: resulting in something that resembles white light instead of a reddish-orange. The snag is that when a metal is close to its melting point, the atoms are barely holding together: A hot tungsten filament slowly falls apart as the metal crystals slide past each other. Additionally, atoms can evaporate from the surface until there’s no wire left. The rate of both of these processes increases with temperature, so there’s a fundamental trade-off between color/efficiency and lifespan.

由于任何灯丝都必须在熔点以下运行，其峰值发射始终处于深红外区。这意味着只有光谱中极高能量的边缘部分对照明有用；温度的微小提升就能使灯泡的效率提高几个数量级。此外，将峰值能量向高频推移能让灯丝产生更短的波长：从而产生接近白色的光，而不是红橙色的光。问题在于，当金属接近熔点时，原子几乎无法结合在一起：炽热的钨丝会随着金属晶体的相互滑动而缓慢解体。此外，原子会从表面蒸发，直到灯丝耗尽。这两个过程的速率都会随温度升高而增加，因此在颜色/效率与寿命之间存在着根本的权衡。

The lightbulb everyone always cites in the story is hanging in a California fire department. It’s been running nearly continuously for over 120 years and racked up over a million hours of operation. Impressive right? What almost no one talks about is that it’s hardly even glowing! Photo taken by Wikipedia user Rjaerial. Despite nominally being a 60 W lamp, it draws only 4 watts… and is a lot dimmer than you’d expect from a 4 W lamp due to its poor efficiency. There isn’t any documentation, but in all likelihood, the bulb was made wrong and ended up with a very high filament resistance. That’s why it was sold as a night light, because it wasn’t usable for anything else.

故事中每个人都会提到的那个灯泡，正挂在加利福尼亚州的一个消防局里。它已经连续运行了120多年，累计工作时间超过一百万小时。很惊人对吧？但几乎没人提到的是，它几乎都不怎么发光了！照片由维基百科用户Rjaerial拍摄。尽管名义上是一个60瓦的灯泡，但它实际功率仅为4瓦……而且由于效率极低，它比你预期的4瓦灯泡要暗得多。虽然没有相关文档，但极有可能是这个灯泡制造时出了差错，导致灯丝电阻过高。这就是为什么它被当作小夜灯出售，因为它根本无法用于其他用途。

Early bulbs (like that one) were handmade, and quite expensive. Because of this, they were universally optimized for long lives. This resulted in light that isn’t anywhere near white, and an efficiency that was a tiny fraction of a modern incandescent lamp (which are also terrible by any objective standards). Once the production process was automated, new bulbs cost pennies, so it made sense to optimize them to actually work… because long-lasting bulbs cost more money to operate: Going off modern-day prices, electricity costs around 0.10 [$/kW*h], so a 60 W lamp will consume 6$ of electricity over a 1,000 hour lifespan. Considering that such a lamp only costs around 3$, installing one that lasts longer but uses more power would be silly.

早期的灯泡（如那个灯泡）是手工制作的，非常昂贵。因此，它们普遍被优化为长寿命。这导致发出的光远非白色，且效率仅为现代白炽灯的一小部分（而现代白炽灯按任何客观标准来看也都很糟糕）。一旦生产过程实现自动化，新灯泡的成本就降到了几美分，因此将它们优化为“真正好用”才合乎逻辑……因为长寿命灯泡的运行成本更高：按现代价格计算，电费约为0.10美元/千瓦时，因此一个60瓦的灯泡在1000小时的寿命内将消耗6美元的电费。考虑到这样一个灯泡本身仅需约3美元，安装一个寿命更长但更耗电的灯泡显然是愚蠢的。

Case in point, despite the cartel only lasting for 14 years, non-halogen, incandescent light bulbs still last around 1,000 hours (usually ranging between 500 to 2,500 hours). Instead of “making bulbs last longer,” manufacturers spent huge amounts of time and money developing entirely new technology: fluorescent and LED lamps. These don’t use a wire on the very edge of melting, so they can be made to both work well and last a long time (… although bulb-style LEDs tend to overheat). Lamps intended for other applications often strike a different balance: In photography, a truly white light is desirable, which results in specialized “photoflood” bulbs that only last for a few hours. In the other direction, many indicator lamps are designed for 100,000 hours because they are difficult to replace.

事实证明，尽管那个卡特尔（垄断组织）只存在了14年，但非卤素白炽灯的寿命依然维持在1000小时左右（通常在500到2500小时之间）。制造商并没有把精力花在“延长灯泡寿命”上，而是投入了大量时间和金钱开发全新的技术：荧光灯和LED灯。这些灯不需要使用处于熔点边缘的金属丝，因此它们既能高效工作又能长久使用（……尽管灯泡形状的LED往往容易过热）。用于其他用途的灯泡通常会采取不同的平衡点：在摄影中，需要真正的白光，因此产生了寿命仅几小时的专用“摄影泛光灯”；而在另一个极端，许多指示灯被设计为10万小时寿命，因为它们很难更换。

Ok, but what’s with the testing? If long-lived light bulbs are worse products, why would they need a cartel to enforce a thousand-hour limit? Well, it’s because people think long-lasting bulbs are a good product: Lifespan is something everyone can understand, and has a direct effect on when you will have to go back to the store: if you saw two 60 W bulbs in a store, one claiming to last 400 hours and the other 2,000 hours, you’d probably get the…

好吧，那测试是怎么回事？如果长寿命灯泡是更差的产品，为什么他们需要一个卡特尔来强制执行1000小时的限制？嗯，这是因为人们认为长寿命灯泡是好产品：寿命是每个人都能理解的概念，并且直接影响你何时需要再次去商店：如果你在商店里看到两个60瓦的灯泡，一个声称寿命为400小时，另一个为2000小时，你很可能会买那个……