The incorrect parameter settings of transducer and instrument will result in poor imaging quality and defect recognition difficulty in ultrasonic phased array inspection. To improve the imaging quality of ultrasonic phased array testing, the factors of ultrasonic phased array imaging were analyzed. Then the effects of aperture, focal length and pulse width on ultrasonic phased array imaging were studied and verified by experiments using the control variable method. The influence law of parameters of ultrasonic array transducer and instrument on imaging quality was obtained. And the method to o...