石墨烯薄膜声源声场特性测试及电路改进

Acoustic field measurement and circuit improvement of graphenefilm sound source

针对石墨烯薄膜优异的导热导电性,基于热致发声原理,构建了石墨烯薄膜声源系统。设计并制作了不同基底的石墨烯薄膜声源,利用最新声压公式分析其声压影响因素,并对声场特性进行了测试,从而验证了石墨烯薄膜作为新型声源的可行性。针对石墨烯薄膜声源存在的"频率失真"问题,提出了同相运算放大电路的改进方法,使原输入交流信号与直流偏置电压在运放电路输出端叠加,从而使输出声信号端产生与输入交流电频率同频率的一倍频声信号。

Aiming at the excellent thermal conductivity of graphene films, a graphene film sound sourcesystem was constructed based on the principle of thermoacoustic effect. The influence of the soundpressure on the sound pressure was analyzed by using the latest sound pressure formula, and the acousticfield characteristics were tested and verified as the feasibility of the new sound source. Aiming at the＂frequency distortion＂ problem of graphene thin film loudspeaker, An improved method of the in-phaseoperational amplifier circuit is proposed to superimpose the original input AC signal and the DC biasvoltage at the output end of the operational amplifier circuit so that the output sound signal terminal withthe input AC frequency with the same frequency of the frequency sound signal.