The investigation of an alternate approach to nondestructive, nanoscale mechanical imaging for IC interconnect structures is reported. This approach utilizes a heterodyne interferometer based on a scanning probe microscope, also referred to as heterodyne force microscopy (HFM). This interferometer is sensitive to the relative phase difference of the two ultrasonic excitations due to spatial var...

High-resolution volumetric optical imaging modalities, such as confocal microscopy, two-photon microscopy, and optical coherence tomography, have become increasingly important in the biomedical imaging field. However, due to strong light scattering, the penetration depths of these imaging modalities are limited to the optical transport mean free path in biological tissues, for example, ∼1 mm in...

The conventional ultrasonic imaging techniques including the holographic one give a high resolution in angle, but a relatively poor resolution in range, because the resolution in range is obtained only by use of selective focus or parallax useful only with a small focal ratio. This paper presents the principle and some experimental results of new ultrasonic imaging techniques that use a linear ...

A capacitive micromachined ultrasonic transducer structure for use in underwater imaging is designed, fabricated and tested in this paper. In this structure, a silicon dioxide insulation layer is inserted between the top electrodes and the vibration membrane to prevent ohmic contact. The capacitance-voltage (C-V) characteristic curve shows that the transducer offers suitable levels of hysteresi...

There are several techniques that may be used in the tomographic imaging of structural and geotechnical systems. X-ray tomography and ultrasonic imaging are two of the extreme techniques as functions of resolution and costs. On one hand, X-ray tomography allows the collection of high-resolution images in small specimens that may be removed from the structure. The application of X-rays in the fi...

Intramedullary nail internal fixation is the most prevalent method of treatment of fracture. The study on hole testing and localization of intramedullary nail is one of the most important research topics in present-day orthopedic medicine. This paper gives a new method for hole testing of intramedullary nail based on ultrasonic sensor. Considering the disadvantage, ultrasonic attenuates too fas...