Abstract: The focusing characteristics and imaging processing of the ultrasonic focused field excited by a concave linear phased array are studied. At first, the phased focused field radiated by the concave linear phased array is investigated. The influence of apodization, interelement spacing, f number and other parameters on the transient field excited by the concave linear phased array is analyzed in detail. Then, the scattering field of the phased focusing field on an inhomogeneous object is also studied. The B-scan imaging of the linear scan is obtained by the concave linear phased array. Next, the imaging processing is carried out by the scattering field on the inhomogeneous object. The inspection imaging is also investigated and obtained for the tube inspection by the compressional wave scanning.