Abstract
This paper describes newly developed ultrasound ring array probes. In one probe, eight transducers were aligned circularly and turned toward the central axis of the probe. The other one has an ultrasound transducer with convex surface at the center of the probe and eight transducers was set to surround the transmitter and used as receivers. Using these probes, we performed experiments to reconstruct a 3D image of a measurement object. The experimental results indicated these probes has the availability for high resolution imaging.