Fabrics that lets light through but stops sound
The weave of the new translucent fabric traps sound, while letting light in. Noisy rooms are no fun, but neither are those smothered in heavy sound-canceling drapes. The solution? A translucent curtain that quenches sound by behaving like foam, developed by Swiss materials scientists and a textile designer. To get a grip on what kind of curtain would block sound but not light, the research team at the Swiss Federal Laboratories for Materials Science and Research built a computer model of the acoustic qualities of fabric. This model helped pinpoint the exact proper- ties—for example, the fabric’s density and the shape of the microscopic holes that pepper it—that the new textile would require. They then passed their findings off to the designer, Annette Douglas, to turn into reality. The curtains were tested in a seminar room built specifically for measuring acoustics. Douglas—who has been working to make see-through, sound-stopping curtains for a while, having won a prize in 2005 for her plan for acoustic barriers in open-plan offices—worked with a variety of yarns and developed a new weave pattern for the fabric. The new curtain absorbs five times as much sound as regular translucent fabrics. “Acousticians are pretty astonished when they see the readings we are achieving with the new curtains in the reverberation room,” the lead researcher said in a press release. Regular see-through draperies cut down on the time a sound bounces around a room by only 2–3%. These babies cut it by 20%. The basic principle of how sound energy is absorbed by the new textile is the same as in foam; both are porous sound absorbers. The air moving inside the textile is slowed down by friction, which causes a conversion of sound energy into thermal energy. This combination of qualities in a curtain is a first, and the lead researcher reports that there’s already a lot of interest from potential buyers.
Original sources: http://blogs.discovermagazine.com/80beats/?p=28822#.UkB22CjtVDg