New technique for linearly converging ultrasonic waves radiated by a stripe-mode vibrating plate

Abstract

We developed a new technique for linearly converging ultrasonic waves radiated by a rectangular stripe-mode vibrating plate. In conventional sources of ultrasonic waves, emission direction converters are used to linearly converge ultrasonic waves radiated by vibrating plates. However, the emission direction converters had such complicated constructions that they had problems such as the difficulty of manufacturing and maintaining them. The converging technique proposed by us uses a concept different from the conventional one, and therefore it has the significant features that the reflectors used have a much simpler structure and a better characteristic of converging ultrasonic waves than the conventional ones. We experimentally manufactured an ultrasonic source at 50 kHz, and confirmed that it could realize the formation of a linearly converged high-intensity sound field having the same length as the vibrating plate.

Improved method of imaging defect in noncontact and nondestructive technique by high-intensity aerial burst ultrasonic wave and optical equipment

“…It seems reasonable to assume that this method will be able to avoid the effects of the vibration mode so long as the system measures the vibration almost immediately after irradiation by the sound wave. However, in a previous study, [10][11][12] an aerial ultrasonic sound source of bolt-clamped Langevin type [13][14][15][16][17] could not generate a suitable high-intensity burst wave because the rise time of the transducer was too long (approximately 40-60 ms). Therefore, we imaged defects in solid material by applying a burst wave from a point converged sound source via an ultrasonic transducer that has a short rise time (approximately 1 ms).…”

Aerial intense ultrasonic source integrating the horn and vibrating plate

“…25,26) Furthermore, to form a focused sound field, reflecting plates are used to collect the radiated sound waves at one point. [27][28][29][30][31] Consequently, larger devices have been required to form these sound fields.…”

High-intensity aerial ultrasonic source with sharp directivity containing a compact circular vibrating plate

“…There are also rectangular, [19][20][21][22][23][24] square, 25,26) and circular transverse vibrating plate sources 27,28) that can emit high sound pressure sound waves into the air. These use transverse vibrations to generate large vibration displacements in vibrating plates.…”