Were the first sunglasses made to hide your eyes, not to block the sun?

What were the first sunglasses?

Inuit in the Arctic carved eye shields from walrus ivory, bone, antler or wood, with two narrow slits to look through. The Science Museum in London says they were developed some 2,000 years ago. Guinness World Records dates the oldest examples to the first century CE, with finds from archaeological sites in Alaska and Siberia.

The purpose was the sun. The Canadian Museum of History describes how snow goggles work like sunglasses and protect the eyes from sunlight reflecting off ice and snow. Without them, a hunter risked snow blindness, a painful condition the museum likens to sunburn on the eyes. The museum's own pair, found in an early Inuit house on Baffin Island, is dated to between 1000 and 1600 CE.

Snow goggles had no lens. They worked because the slit let in less light. The principle is the same in every pair of sunglasses since: decide which light reaches the eye.

Is the story about the Chinese judges true?

The story goes like this. In China about 900 years ago, people held flat panes of smoky quartz in front of their eyes. Judges are said to have worn them during trials, so that no one could read their faces. The Science Museum repeats it, as does Torquay Museum in England, which places the practice in the 12th century and says it may be older.

The problem is the source. The Science Museum writes that some historical accounts describe the judges, without saying which. Torquay Museum gives no source at all. We have not found any surviving document from the period that describes the practice, only the same sentence passed from page to page.

Research on eyeglasses in China also points to a later date. A 2016 study in the Bulletin of the School of Oriental and African Studies follows the development of eyeglasses in China from the 15th to the 19th century and notes that claims of eyeglasses arriving as early as the Yuan dynasty lack solid evidence. The study is about glasses for vision, not quartz panes, but it shows how hard early claims are to pin down.

What you can actually hold is younger. Torquay Museum has a pair of Chinese sunglasses about 200 years old, with wooden frames and lenses of fine gauze, from a mandarin's residence in Zhenjiang before 1842.

Did Nero watch gladiators through an emerald?

The other classic example is the emperor Nero. Pliny the Elder writes in his Natural History, book 37, that Nero used to watch gladiator fights in a reflecting smaragdus. The word was used for several green stones, and the sentence comes right after a passage on how such stones reflect images.

The historian David Woods argued in 2006 in the journal Arctos that the anecdote probably rests on a misreading of an earlier source, in which Nero watched the games like a spy rather than through a mirror. Whichever reading is right, it is a stone, not a pair of glasses.

What does the video get right, and what does it get wrong?

Viktor says the first sunglasses were not for the sun. That line does not hold. The oldest documented sun protection for the eyes, snow goggles, was made for exactly that, and it is about a thousand years older than the story of the judges.

What is right is that tinted glass took on jobs other than stopping sun early on. The judges' smoky quartz is one such story, even if it is weakly documented. Another is better recorded: the English instrument maker James Ayscough experimented in the mid-1700s with blue- and green-tinted glass in spectacles, because he believed the colour could correct certain vision problems, according to London Museum. A fairer version of the line would be that some of the first tinted glasses were not for the sun.

When did everyone start wearing sunglasses?

Not until the 20th century. The Science Museum describes how Foster Grant sold sunglasses to beachgoers in Atlantic City in 1929, and how polarising lenses were invented in Massachusetts in the 1930s. From then on, dark glasses became both protection and style.

What does a tinted lens do today, if it is not for the sun?

It chooses which light gets through. A lens for the evening does not need to make the room dark. It needs to take out blue light, which the eye's clock cells are most sensitive to and which screens and LED lamps give off plenty of. Why blue in particular counts is covered in Your eye's third cell type.

In the video, Viktor wears LOWLIGHT 03 in a black frame with the orange lens, the evening lens. It is orange for the same reason fire is, which we wrote about in Firelight is orange. The figures below are each lens's filtration according to the supplier's spectral measurement per lens tint.

It will not give you a poker face. But it does what snow goggles once did, only for the evening: it decides which light reaches the eye.