Although I’ve mentioned my own skepticism about the utility of a flexible smartphone (see “Why Do We Want a Flexible Phone?”), the quest for that grail continues apace. Screens are just the beginning of that quest (see “Flexible Smartphone Batteries”), and researchers are now broaching the interesting question of how to achieve flexible speakers.
Flexible things are soft. But the vibrating plate of speakers can’t be soft, or they’d absorb their own sound. A seemingly insolvable conundrum.
Yet solve it Fujifilm has. The trick is to make speakers out of a material that’s hard when it needs to be hard, and soft when it needs to be soft. As ExtremeTech and others explain, the key was to develop a so-called “viscoelastic polymer.” For something to be viscoelastic, it needs to be viscous at some times, elastic at others. (Think of your Tempur-Pedic mattress, for instance, which obeys the same property.)
As a Fujifilm rep put it to Diginfo: “This film is normally soft, but it becomes hard in the audio frequency range. That’s because it’s designed so that, when the ceramic vibrates in the audio range, from 20 Hz to 20 kHz, the vibrational energy is transmitted to the entire film.” When it needs to be malleable, the film will oblige. When it needs to be rigid in order to push out those beats, the film rises to that task, too.
To prove their point in a particularly spectacular fashion, Fujifilm bent a speaker into an origami swan, and it still worked. Check out this video.
ExtremeTech has some more details on the composition of the speaker: the viscoelastic polymer is mixed with “piezoelectric” ceramic (see “A Heartbeat-Powered Pacemaker” for more on piezoelectricity), which is in turn “housed within electrodes and a protective shell.” Voltage from those electrodes causes the polymer to vibrate, producing sound. Nikkei has a few more details on how the tech works, including a strategy to release strain energy as heat, thereby preventing cracks.
It’s cool technology, for sure. Unfortunately, Fujifilm hasn’t been forthcoming about when, if ever, it stands to be commercialized. (It was touted at nano tech 2013, a conference in Tokyo that wound up last Friday.) Keep clamoring for those flexible smartphones, though, and it might just be around the corner.
How AI is reinventing what computers are
Three key ways artificial intelligence is changing what it means to compute.
These weird virtual creatures evolve their bodies to solve problems
They show how intelligence and body plans are closely linked—and could unlock AI for robots.
Our brains exist in a state of “controlled hallucination”
Three new books lay bare the weirdness of how our brains process the world around us.
We reviewed three at-home covid tests. The results were mixed.
Over-the-counter coronavirus tests are finally available in the US. Some are more accurate and easier to use than others.
Get the latest updates from
MIT Technology Review
Discover special offers, top stories, upcoming events, and more.