| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a high quality microphone unit capable of obtaining excellent distant noise suppression performance in a wide frequency band and downsizing its size. <P>SOLUTION: A microphone unit 1 comprises: an electro-acoustic conversion element 13 for converting a sound signal into an electric signal based on vibration of a diaphragm 134; and a case body 10 for housing the electro-acoustic conversion element 13. The case body 10 is provided with a first leading sound space SP1 housing the electro-acoustic conversion element 13, and a second leading sound space SP2 having a different shape from the first leading sound space SP1 and separated from the first leading sound space SP1 by arrangement of the electro-acoustic conversion element 13. A cross-sectional area reducing section AR is provided at an inner side of the second leading sound space SP2 apart from the second opening 19 for, compared to its front and behind, locally reducing a cross-sectional area of a sound path cross section crossing almost orthogonally against a traveling direction of a sound wave. <P>COPYRIGHT: (C)2012,JPO&INPIT |
