| 摘要 |
PURPOSE:To increase the number of bits corresponding to PCM digital signals by radially dividing one of plane electrodes at an almost uniform angle and forming plural unit electrodes concentrically divided so that the areas of respective divided units are increased at the rate of 2<n> times in the radial direction. CONSTITUTION:The digital speaker is provided with an electric/acoustic converter for extracting sound pressure by impressing voltage between a pair of plane electrodes 2, 3 and one electrode 3 is radially divided at the almost uniform angle and forms plural unit electrodes 3a to 3c concentrically divided so that the areas of respective units are increased at the rate of 2<n> times in the radial direction. Since the plane electrode 3 is divided in both the circumferential direction and radius direction, many unit electrodes 3a to 3c can be constituted, and since the areas of respective units are increased at the rate of 2<n> times in the case of dividing the electrode 3 in the radial direction, the areas proportional to the weight values of respective bit digits can easily be obtained. Consequently, the number of bits corresponding to PCM digital signals can be increased and the digital speaker having a large dynamic range can be obtained. |
