Hashimoto Sota, Takase Yuki, Inoue Tomoyoshi, Nishio Kenzo, Xia Peng, Rajput Sudheesh K, Matoba Osamu, Awatsuji Yasuhiro
Appl Opt. 2022 Feb 10;61(5):B246-B254. doi: 10.1364/AO.444760.
We propose a simultaneous imaging technique of both sound propagations and spatial distribution of acoustic frequencies. We experimentally demonstrated the proposed technique for the acoustic waves of frequencies 39,500 and 40,500 Hz, which have close sound pressure. The sounds were recorded at the framerate of 100,000 fps by parallel phase-shifting digital holography. To obtain the distribution of the acoustic frequencies, the short-time Fourier transform analysis was applied. The simultaneous imaging was carried out by assigning the frequencies and the pixel values of the phase-difference images to the components of HSL color space. The images obtained by the proposed technique represent the frequencies with the hue in addition to the sound propagations with the luminance. We succeeded in imaging the spatiotemporal evolution of the spatial frequencies of the sounds.
我们提出了一种同时对声音传播和声学频率空间分布进行成像的技术。我们通过实验证明了该技术适用于频率为39500赫兹和40500赫兹的声波，这两种声波具有相近的声压。通过并行相移数字全息术以100000帧每秒的帧率记录声音。为了获得声学频率的分布，应用了短时傅里叶变换分析。通过将相差图像的频率和像素值分配给HSL颜色空间的分量来进行同步成像。所提出的技术获得的图像除了用亮度表示声音传播外，还用色调表示频率。我们成功地对声音空间频率的时空演变进行了成像。
