| 摘要 |
PROBLEM TO BE SOLVED: To provide an electroacoustic transducer using high frequency discharge, capable of stabilizing an oscillation frequency of a self-excited oscillator for generating a high frequency signal, preventing frequency shift in the oscillation frequency caused by a voice signal inputted, and preventing drift in the oscillation frequency in silent period.SOLUTION: The electroacoustic transducer includes a needlelike electrode 3, an electroacoustic conversion unit 10, a high frequency oscillation circuit, and a modulated signal extractor 22. The counter electrode 4 is countered to the needlelike electrode 3. The electroacoustic conversion unit 10 is equipped with a discharge portion formed between the needlelike electrode 3 and the counter electrode 4. The high frequency oscillation circuit contains the discharge portion and generates high frequency discharge in the discharge portion. The modulated signal extractor 22 extracts a signal modulated according to sound waves, oscillated at the high frequency oscillation circuit and introduced into the discharge portion. The high frequency oscillation circuit configures a voltage controlled oscillator, of which the oscillation frequency is controlled by voltage corresponding to the modulated signal extracted by the modulated signal extractor 22. |
