In traps made of sound, whose shape is encoded in the metamaterial. (D) A sound projector. Two metamaterial lenses (white), like the one in (B), are attached to motors that change their mutual distance. Using a movement sensor, like the one used by the XBOX console, allows acoustic signals to be delivered to a moving person. (E) In this experiment, the metamaterial placed in front of the speaker acts like a prism, splitting melodies (that contain multiple notes) into an “acoustic rainbow,” where each note goes in a different direction, like the colors in a rainbow (photograph credits: Sussex University). “And,” adds the team captain, “only a limited number of unit cells is needed.
Just like any word can be made from various combinations of just 26 letters in the Latin alphabet, we can make acoustic metamaterials from a collection Spain phone number list of just 16 different bricks. Bricks can be used like building with LEGO®–we can assemble them into useful structures such as lenses, that can fit into the palm of the hand (Figure 3B). When unit cells work together, they can achieve incredible feats” (to read more about the acoustic superpowers of moths, see this Frontiers for Young Minds article). He continues, “Acoustic lenses are based on diffraction but can be used to magnify and direct sound, just like lenses for light.
We can use these lenses to set the direction of sound from loudspeakers and, like a lens for light creates the beam of a lighthouse, we can shape a beam of sound that travels great distances. Imagine how this might help us deliver sound effects in a cinema or theater [2]!” The second member of Team Sound adds, “We can also combine two acoustic lenses, similar to the way optical lenses are used in cameras and telescopes. By adjusting the distance between the lenses, we can deliver sound to a specific location. We can use a programmable circuit board and a motor, in a set-up that looks like a camera, to create the acoustic equivalent of “autofocus” (Figure 3C), which we can deliver sound to a moving person, tracked by an Xbox Kinect.