Korea Institute of Machinery & Materials

Eun Joong Lee

Shin Hur

Duck Gyu Lee

Kyungjun Song

A directional sound apparatus includes a planar shape plate and a sound wave generator. The planar shape plate has a plurality of grooves formed on a surface of the planar shape plate. The sound wave generator is configured to radiate a sound wave to outside from the surface of the planar shape plate. A width of each of the grooves and a distance between the grooves adjacent to each other are smaller than a wavelength of the sound wave. The planar shape plate has a plurality of cell areas in which at least one groove is included. A structure of the groove included in a first cell area is different from that of the groove included in a second cell area adjacent to the first cell area, so that surface admittance in the first cell area is different from that in the second cell area.

Growing community of inventors

Daejeon, South Korea

Eun Joong Lee