Why Does Everything Look Green Through Night Vision Goggles?

istock.com/nightman1965
istock.com/nightman1965

The characteristic green tint is by design, for a few reasons. First, device makers have experimented with a few different colors and found that the different shades that make up the monochrome night vision image are most accurately perceived and distinguished when they’re green. In other words, while the night vision images you’ve seen in Silence of the Lambs and Call of Duty might seem a little clunky, green presents a night vision device wearer with the most accurate and user-friendly picture possible. What’s more, because the eye is most sensitive to light wavelengths near 555 nanometers - that is, green - the display can be a little dimmer, which conserves battery power.

Who Invented Night Vision?

The first practical night vision devices were developed in Germany in the mid-1930s and were used by both German tanks and infantry during World War II. U.S. Military scientists had simultaneously developed their own night vision devices that first saw use during WWII and the Korean War.

These “Generation 0” devices used active infrared to brighten up a scene. Soldiers carried an IR illuminator to shoot a beam of near-infrared light that then reflected off objects and bounced back to the lens of their scope and created a visible image of what they were looking at. The illuminators used by the German Nachtjägers, or "night hunters", were about the size of dinner plates and required a large power supply carried on the soldier’s back.

The technology made huge leaps in the following decades, and by the time the U.S. entered the Vietnam War, many troops were outfitted with passive "starlight scopes" that used image-intensifying tubes to amplify available ambient light (usually from the moon and stars, hence the name) and produce an electronic image of a dark area.

This “Generation 1” technology is still around today in the more budget-friendly consumer-grade night vision devices. Military and police forces have upgraded to successive generations of tech with new improvements over the years, but image intensifying night vision - there’s also another flavor, thermal imaging, but image intensification is almost always the kind you see in movies and games - still works on the same basic principles as these early models.

I Can See Clearly Now

The lens or lenses at the end of a night vision scope or pair of goggles gather available light, including some from the lower spectrum of invisible infrared, and focus it on a photocathode on the device’s image intensifier tube, which transforms the photons, or light particles, into electrons.

As the electrons move through the tube, they flow through a microchannel plate, which is a disc with millions of tiny holes, or microchannels, in it. As the electrons strike electrodes on the microchannels, bursts of voltage cause the motion of electrons to increase rapidly, forming a dense clouds of electrons that intensifies the original image.

At the far end of the tube, the electrons hit a screen coated with a phosphor, which is a substance that radiates visible light after being energized. (We talked about phosphors in relation to glow-in-the-dark toys a while ago.) The energy from the electrons excites the phosphor which converts the electrons back into photons. These are in the same alignment as the photons that originally entered the tube, and form the greenish image on the screen inside the viewing lens of the device.

Looking to Downsize? You Can Buy a 5-Room DIY Cabin on Amazon for Less Than $33,000

Five rooms of one's own.
Five rooms of one's own.
Allwood/Amazon

If you’ve already mastered DIY houses for birds and dogs, maybe it’s time you built one for yourself.

As Simplemost reports, there are a number of house kits that you can order on Amazon, and the Allwood Avalon Cabin Kit is one of the quaintest—and, at $32,990, most affordable—options. The 540-square-foot structure has enough space for a kitchen, a bathroom, a bedroom, and a sitting room—and there’s an additional 218-square-foot loft with the potential to be the coziest reading nook of all time.

You can opt for three larger rooms if you're willing to skip the kitchen and bathroom.Allwood/Amazon

The construction process might not be a great idea for someone who’s never picked up a hammer, but you don’t need an architectural degree to tackle it. Step-by-step instructions and all materials are included, so it’s a little like a high-level IKEA project. According to the Amazon listing, it takes two adults about a week to complete. Since the Nordic wood walls are reinforced with steel rods, the house can withstand winds up to 120 mph, and you can pay an extra $1000 to upgrade from double-glass windows and doors to triple-glass for added fortification.

Sadly, the cool ceiling lamp is not included.Allwood/Amazon

Though everything you need for the shell of the house comes in the kit, you will need to purchase whatever goes inside it: toilet, shower, sink, stove, insulation, and all other furnishings. You can also customize the blueprint to fit your own plans for the space; maybe, for example, you’re going to use the house as a small event venue, and you’d rather have two or three large, airy rooms and no kitchen or bedroom.

Intrigued? Find out more here.

[h/t Simplemost]

This article contains affiliate links to products selected by our editors. Mental Floss may receive a commission for purchases made through these links.

Who Were the Actual Brooks Brothers?

Phillip Pessar, Flickr // CC BY 2.0
Phillip Pessar, Flickr // CC BY 2.0

Brooks Brothers has been a mainstay of American formal wear for more than 200 years. The company’s suits have been worn by 40 U.S. presidents. They have supplied uniforms to the American armed forces and suits to regular people for their most important life events: going to the prom, attending their first job interview, getting married.

But in July 2020, the firm filed for bankruptcy, likely a victim of the working-from-home trend and the move towards more casual clothing. The Brooks Brothers’s name has been woven into the fabric of American fashion, yet a certain mystery surrounds the people behind the business. Who were the original Brooks Brothers, anyway?

The firm that would go on to be known as Brooks Brothers was established on April 7, 1818, by 45-year-old Henry Sands Brooks and his younger brother, David, as H & D. H. Brooks and Co. Before setting up the store, Henry Sands Brooks had been a provisioner for traders and seafarers, and likely did brisk business in New York City’s seaport. Their shop was situated on the corner of Catherine and Cherry streets in Lower Manhattan, a major shopping district that supported a number of clothing stores. It was said Brooks was something of a dandy with an eye for fashion.

Brooks Brothers ran a full-page ad celebrating its centenary in 1918.New York Evening Post // Public Domain

Henry Sands Brooks died in 1833, and the store passed to his eldest son, Henry Jr. When he died in 1850, Brooks Sr.’s four younger sons Daniel, John, Elisha, and Edward inherited the firm and renamed it Brooks Brothers. At this point, the store began to stand out from the crowd. The brothers adopted their familiar logo of a sheep suspended by a ribbon representing the Golden Fleece. This ancient symbol hearkened back to the Greek legend of Jason and the Argonauts, and was used by tailors and wool merchants across Europe as a sign of quality. By embracing this symbol, the brothers were announcing the caliber of their goods and aligning themselves with the prestige of European fashion.

While building a brand on traditional quality, the brothers also saw an opportunity to modernize. Brooks Brothers began specializing in ready-to-wear suits—an innovation that made “gentlemen’s clothing” accessible and affordable to ordinary Americans. An advertisement in New York’s Evening Post in June 1850 stated that Brooks Brothers ‘have on hand a large stock of ready-made clothing, suited to the tastes and wants of purchasers.’ Brooks Brothers also capitalized on the California Gold Rush by selling their ready-made suits to gold-seekers who didn’t have time to wait for a tailor to construct bespoke suits.

Business boomed in the years leading up to the Civil War, a time when the company benefited from slavery. Much of the cotton used by Brooks Brothers was picked by enslaved laborers in the South. The company also manufactured the types of uniforms worn by enslaved people forced to work as house servants.

Perhaps as a result of their experience making such clothing, Brooks Brothers was given a large contract by the Union government at the start of the Civil War to provide tens of thousands of uniforms for enlisted soldiers. A scandal blew up when the garments were delivered: it was obvious that the uniforms were of low quality, missing buttons or buttonholes, and made from cheap scraps of cloth glued instead of sewn together. When the outfits were exposed to wind and rain, they fell apart. In the rush to manufacture them for the war effort, Brooks Brothers had, in fact, substituted cheap and flimsy material instead of the usual grade of cloth—they were allowed to, according to the provisions written into their contract.

The New York state legislature launched an investigation, accusing the company of profiteering. When asked how much money the company had made by downgrading the cloth, Elisha Brooks prevaricated. “I think that I cannot ascertain the difference without spending more time than I can now devote to that purpose,” Brooks told lawmakers. Ultimately, Brooks Brothers agreed to replace 2350 of the substandard uniforms at a cost of $45,000.

An illustration of looters throwing trousers and other garments out of the Brooks Brothers store during New York City's draft riots appeared on the front page of Frank Leslie's Illustrated Newspaper on August 1, 1863.Frank Leslie's Illustrated Newspaper, 19th Century American Newspapers, Gale Primary Sources // Public Domain

The company’s association with outfitting the Union Army got them into trouble again in July 1863. The casualties among members of New York regiments were increasing as the war showed no signs of resolution. In New York City, working class people protested against the draft, and the protests quickly turned into a riot of racist violence and looting. Brooks Brothers’s Cherry Street store was one of the establishments it targeted. Harper’s Weekly reported that “a large number of marauders paid a visit to the extensive clothing-store of Messrs. Brooks Brothers … there they helped themselves to such articles as they wanted, after which they might be seen dispersing in all directions, laden with their ill-gotten booty.”

Brooks Brothers’s reputation didn’t suffer for long, however. At his second presidential inauguration in March 1865, Abraham Lincoln wore a greatcoat made by the company. It featured an eagle embroidered into its lining with the motto “One Country, One Destiny.” Lincoln was wearing the same coat when, just two weeks later, he was assassinated at Ford’s Theatre in Washington, D.C. After his death, Mary Todd Lincoln gave the coat to Alphonse Donn, a doorman at the White House, who kept it for the rest of his life. Donn’s family eventually sold the coat to the United States Capitol Historical Society, and it is now in the Ford’s Theatre museum's collection.

Brooks Brothers continued to grow and expand. The company introduced enduring fashions such as the button-down polo shirt in 1896, the sack suit in 1901, and their own version of a British regimental tie, the striped rep tie, in 1902.

For more than 200 years, the company has outfitted presidents, Wall Street traders, and businesspeople, becoming an iconic American brand with worldwide appeal. But today, their future may be less certain.