Youtube user, 落合陽一
Youtube user, 落合陽一

Scientists Create 3D Laser Holograms That Are Safe To Touch

Youtube user, 落合陽一
Youtube user, 落合陽一

3D laser holograms sound cool, but they're generally hot. As in, hot enough to burn your skin. But now researchers at the Digital Nature Group, a Japanese lab, say they've figured out a way to create a 3D laser hologram that is not only safe to the touch but interactive.  

These "fairy lights" holograms are composed of light pixels called voxels fired at superfast speeds. (How fast? The laser bursts last 30 to 270 femtoseconds. A femtosecond is a quadrillionth of a second.) Voxels are emitted by plasma that's created when the laser's focused energy ionizes the air. 

Popular Science breaks down how DNG did it:

To create their hologram, researchers fired their femtosecond laser through a spatial light modulator, which continues the beam through a series of lenses, a mirror and a Galvano scanner, which positions a mirror to precisely direct the laser beams. A camera underneath the hologram captures user interaction, allowing the dots to respond to being “touched.”

Each tiny 3D image, many times smaller than the tip of a person's finger, is made up of about 200,000 voxels per second and is interactive based on touch. Some researchers reported that the holograms feel like sandpaper, and others like receiving a static shock. 

The interactive aspect is still simple—you can check a box or "break" a heart, for instance—but being able to touch the holograms at all represents progress.

This isn't the first time scientists have used femtosecond lasers to create images suspended in the air. But previous attempts to do so had less sharp resolution—and burned human skin. The trick to fixing that was making the lasers fire in especially short blasts. Lab studies found that anything longer than two seconds will burn human skin (or at least the leather researchers used to represent human skin). But firing the lasers at bursts from 50 milliseconds to 1 second left the "skin" un-singed.

For a more technical description and a chance to see the holograms in action, check out the video below. The technology is complicated, and likely prohibitively so. That is: don't expect holograms in your house anytime soon. 

[h/t Popular Science]

A Florida Brewery Created Edible Six-Pack Rings to Protect Marine Animals

For tiny scraps of plastic, six-pack rings can pose a huge threat to marine life. Small enough and ubiquitous enough that they’re easy to discard and forget about, the little plastic webs all too often make their way to the ocean, where animals can ingest or become trapped in them. In order to combat that problem, Florida-based Saltwater Brewery has created what they say is the world’s first fully biodegradable, compostable, edible six-pack rings.

The edible rings are made of barley and wheat and are, if not necessarily tasty, at least safe for animals and humans to ingest. Saltwater Brewery started packaging their beers with the edible six-pack rings in 2016. They charge slightly more for their brews to offset the cost of the rings' production. They hope that customers will be willing to pay a bit more for the environmentally friendly beers and are encouraging other companies to adopt the edible six-pack rings in order to lower manufacturing prices and save more animals.

As Saltwater Brewery president Chris Gove says in the video above: “We want to influence the big guys and kind of inspire them to also get on board.”

When Chuck Yeager Tweeted Details About His Historic, Sound Barrier-Breaking Flight

Seventy years ago today—on October 14, 1947—Charles Elwood Yeager became the first person to travel faster than the speed of sound. The Air Force pilot broke the sound barrier in an experimental X-1 rocket plane (nicknamed “Glamorous Glennis”) over a California dry lake at an altitude of 25,000 feet.

In 2015, the nonagenarian posted a few details on Twitter surrounding the anniversary of the achievement, giving amazing insight into the history-making flight.

For even more on the historic ride, check out the video below.


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