Abstract: An ultrasonic probe includes at least one transmission element layer for transmitting ultrasonic waves, at least one reception element layer for receiving ultrasonic waves and which is provided with an electrode on each of both surfaces opposed in a direction of a thickness thereof, and at least one matching layer for matching acoustic impedance. These layers are arranged in this order in a direction of transmitting the ultrasonic waves. The reception element layer is provided with a projecting portion projecting in a direction of elevation from upper and lower layers which sandwich the two electrodes respectively formed on both surfaces of the reception element layer, and at least one of the electrodes is formed by extending to the projecting portion.

Abstract: An ultrasonic probe includes at least one transmission element layer for transmitting ultrasonic waves, at least one reception element layer for receiving ultrasonic waves and which is provided with an electrode on each of both surfaces opposed in a direction of a thickness thereof, and at least one matching layer for matching acoustic impedance. These layers are arranged in this order in a direction of transmitting the ultrasonic waves. The reception element layer is provided with a projecting portion projecting in a direction of elevation from upper and lower layers which sandwich the two electrodes respectively formed on both surfaces of the reception element layer, and at least one of the electrodes is formed by extending to the projecting portion.

Abstract: Provided is a stretching method of an organic piezoelectric material which sequentially performs a primary stretching step for carrying out primary stretching of an organic piezoelectric material which has not been stretched, a heat treatment step for heat treating the organic piezoelectric material subjected to primary stretching, and a cooling step for carrying out secondary stretching of the heat treated organic piezoelectric material while the organic piezoelectric material is cooled down to the room temperature, and is characterized in that tension is applied continuously to the organic piezoelectric material from the primary stretching step to the cooling step without releasing the tension, and heat treatment is carried out while keeping the tension in a range of 0.1-500 kPa.

Abstract: There is provided a surface treated product that moves relatively in a fluid, wherein a surface of the surface treated product has continuous dimples, each dimple having a diameter of 10 to 2500 ?m and a depth of 50 ?m or less. The surface treated product significantly reduces resistance of a fluid to an object in the fluid, and significantly improves a flow state of the fluid.

Abstract: There is provided a surface treated product that moves relatively in a fluid, wherein a surface of the surface treated product has continuous dimples, each dimple having a diameter of 10 to 2500 &mgr;m and a depth of 50 &mgr;m or less. The surface treated product significantly reduces resistance of a fluid to an object in the fluid, and significantly improves a flow state of the fluid.

Abstract: There is provided a hollow casting in which a surface roughness Ra of a casting wall portion surface forming a hollow portion formed by a wall portion is 10 &mgr;m or less. Such a hollow casting can be obtained by a manufacturing method for the hollow casting in which after molten metal is poured into a mold to be molded by casting, processing of removing residual matters on the casting wall portion surface forming the hollow portion and processing of smoothing the casting wall portion surface forming the hollow portion are performed at the same time under predetermined conditions. According to the present invention, a casting which has the hollow portion formed by the wall portion and whose wall portion surface forming the hollow portion is very smooth and which has a low passage resistance can be manufactured at a lower cost without increasing an environmental load in the manufacturing process.