Ultrasound Scanning Systemand Its Layered Imaging Method

Ultrasonic microscopy provides a new tool to show the characteristics andinternal information of the specimen. Acoustic microscopy has obtained a strongability to detect internal defects and achieved higher accuracy in positioning andmorphology. So the theory value and practical significance is obvious.Through study the composition and imaging methods of ultrasound scan imagingsystem, the development of ultrasonic microscopy system is completed. The maincontents are as follows:(1) set up ultrasound scan imaging system using virtual instrumentationtechnology for hardware control, and realize automatic scanning motion and dataacquisition;(2) In order to improve the resolution of the imaging results, a high-performancefocused P (VDF-TrFE) transducer with center frequency up to50MHz, with a smallfocal spot, with high horizontal and vertical resolution is developed, and acoustic lensare not required. The structure and processing technology for the transducer isanalyzed, production of different parameters of the transducer. The frequencycharacteristics transducer is tested by experiment, and the horizontal and verticalresolution of transducer is calculated and tested. On contrast with commercialtransducer, the acoustic parameters and resolution of transducer developed are betterand meet the request of applications.(3) After the comparison of various imaging methods, the layered imagingmethod is proposed based on radio frequency sampling method (RFS), and relatedsoftware has been developed.(4) Based on the transducers and the system developed, the experimental researchof hierarchical structure different types is made, the morphology and internal defectsof block, PCB board, and electronic encapsulation specimen are detected. Theexperimental results of hierarchical structure scanning imaging show thatmicro-defect information can be detected by this method. Therefore the research above has high practical effect.