| 摘要 |
PROBLEM TO BE SOLVED: To detect differences of distributions of acoustic waves within a prescribed area. SOLUTION: When a slider position of a changeover switch 12 is set to position "1", laser light is outputted from light sources 30-1 to 30-9. Therefore, acoustic waves passing areas 1 to 5 on the inside of an annular member 20-1 and areas 6 to 9 on the inside of annular members 20-2 to 20-5 can be detected by laser light reception parts 40-1 to 40-9. When a user puts a microphone 1 in the front of him or her and brings his or her mouth close to the area 5 formed by beams 70-1 to 70-4 and uses the microphone 1 with the periphery of his or her mouth covered with annular members 20-2 to 20-5, the user can detect differences of acoustic waves in areas 1 to 5 in the front of him or her. Acoustic waves detected in areas 6 to 9 are compared to able to detect differences of acoustic waves spreading around his or her mouth, namely, spreading to side faces of his or her face and peripheries of his or her jaws and nose. COPYRIGHT: (C)2006,JPO&NCIPI |
