Matsushita Electric Industrial Co., Ltd.

Koetsu Saitoh

Masami Kawabuchi

Fumio Muramatsu

Satoko Kikuchi

Junichi Satoh

Masakuni Watanabe

An ultrasonic transducer which can produce an ultrasonic image having a high resolution and a high detection depth, including a piezoelectric element having a concave surface on a side where ultrasonic waves are transmitted or received, and first and second acoustic matching layers formed on the concave surface of the piezoelectric element, the first acoustic matching layer being laid on a side near to the piezoelectric element and having a non-uniform thickness with a maximum thickness of about quarter wavelength, and the second acoustic matching layer being laid on the side near to an object to be detected and having a uniform thickness of about quarter wavelength. Thereby, the ultrasonic transducer including the acoustic matching layers having the maximum thickness set to about quarter wave length and the piezoelectric element exhibit a normal distribution type frequency characteristic over a wide range, and can allow the piezoelectric element to have an arbitrary curvature so that an ultrasonic wave can be converged at a position having an arbitrary distance.

Ultrasonic transducer

Disclosed is an ultrasonic probe for use in medical diagnostic systems for examination within a human body. The ultrasonic probe comprises an array of transducer elements for transmission of ultrasonic wave into an examined body and for reception of echo waves returning from the examined body. Further included in the ultrasonic probe is an ultrasonic propagation medium which is provided between the transducer element array and the examined body. The ultrasonic propagation medium is made of a synthetic rubber having an acoustic impedance close to that of the examined body and having a low acoustic attenuation coefficient. Preferably, the synthetic rubber is one of butadiene rubber, butadiene-styrene rubber, ethylene-propylene rubber, and acrylic rubber.

Ultrasonic probe having an ultrasonic propagation medium

An ultrasonic probe having an ultrasonic propagation medium (8) is used in medical ultrasonic diagnostic systems for examination and inspection of inside of an examining body (9) by transmitting and receiving ultrasonic signals. The ultrasonic probe comprises a body (1), and the ultrasonic propagation medium (8) made of rubber cross-linked by cross linking agent. The ultrasonic propagation medium (8) is interposed between the examining body (9) and a portion for transmitting and receiving ultrasonic waves of the body (1) of the ultrasonic probe when the ultrasonic propagation medium (8) is used.

Ultrasonic probe having ultrasonic propagation medium

A plurality of transducers is arranged successively on a common impedance matching layer of a resilient material. Each transducer comprises an elongated piezoelectric element having a width expansion vibrational mode, a pair of first and second electrodes attached to opposite surfaces of the element across its thickness and an elongated block of an impedance matching material disposed between the second electrode and the common impedance matching layer. The common impedance matching layer is bent to take the shape of an arch to conform to the surface of a frame structure which is convexed in the direction of propagation of ultrasonic energy. The piezoelectric elements are secured to the frame so that they bridge the parallel side members of the frame. The piezoelectric members are divided into a plurality of subgroups, each composed of successively arranged elements. The piezoelectric elements of a given subgroup are selected and energized during each clock interval for transmission of focused ultrasonic energy. The subgroup to be selected is shifted linearly to the next by at least one element in response to successive clock pulses. Becuase of the convex shape of the array, the transmitted energy is successively angulated to provide arc scan.

Growing community of inventors

Tokyo, Japan

Koetsu Saitoh