Acoustic Bubble Detection: Acoustic Optical Imaging Techniques for Decompression Studies

摘要

The acoustic-optical imaging process utilizes Bragg diffraction of lightly by a beam of sound to produce an optical image of an acoustically irradiated object. Inasmuch as many materials which are quite opaque to light are, to varying degrees, transparent to certain acoustic frequencies, the technique offers the possibility of visually examining the internal structure of optically opaque bodies. The imaging of internal features is made possible by the fact that different materials and structures often have different acoustic characteristics, thus causing the sound to be reflected, scattered, absorbed and diffracted. These factors cause perturbation in the acoustic wavefronts which are transformed in the light-sound interaction into a visual image, in real time, which may be observed by eye photographed by a camera, or processed by other conventional optical methods. This program was directed toward an evaluation of the acoustic-optical imaging technique as a means of detecting bubbles formed in the circulatory system during decompression. (Author)