| 摘要 |
PROBLEM TO BE SOLVED: To prevent a resonance phenomenon from being generated by communicating spaces having different thicknesses.SOLUTION: A filling part 51, a filling part 52 and a filling part 53 are provided, such that spaces having equal thickness are communicated from a space OC to a space CS3. Further, the thickness of the space between a diaphragm 87 and the filling part 53 is equal with the thickness of the space between an edge 89 and the filling part 53, and spaces having equal thickness are also communicated within a back cavity BC. Thus, the resonance phenomenon can be prevented from being generated by communicating spaces having different thickness.SELECTED DRAWING: Figure 6 |
