Simultaneous high-speed digital recording of vocal fold vibration and speech signal

A new method for the high-speed digital recording of the vocal fold vibration is presented. The method employs a solid endoscope, a solid-state image sensor and a digital image memory. About 100 frames of continuous image data with 50 × 50 picture elements can be stored in the image memory at one time. Image recording at a rate of 2000 frames per second was achieved using a small light source of a 250 W halogen lamp. The method enables to record the speech signal without special consideration on the camera noises, and also to observe the recorded image on the spot through CRT display. An example of the image data with simultaneously recorded speech and EEG signals are presented comparing the male and female voices, and the chest voice, falsetto and breathy voice.