Preliminary results of the ultrasonic characterization of cutaneous wound tissue and surrounding margin, obtained with the scanning laser acoustic microscope, show an increase in the speed of sound and in the acoustic heterogeneity as function of wound age. As the wound age increased, the following results were noted: (1) The wound area, initially quite homogeneous in acoustic appearance, becam...

Subwavelength resolution in a transmission acoustic microscope configuration is demonstrated using optical fiber-tip sensors as small-sized acoustic probes. A slit with a width of 1/20 of the acoustic wavelength L representing the object was detected with a lateral resolution of the outer fiber diameter which was '1/10 L, and with a proper signal-to-noise ratio. Fiber preparation techniques may...

A phase sensitive laser probe in which the focussed spot is small, as compared with the acoustic wavelength, is capable of measuring the complex distributions of a SAW field along prescribed scan lines. Using the probe, it is possible, on a defect free sample, to measure the SAW velocity surface with an accuracy of a few parts in 10s. Such accuracy suggests that the technique is sufficiently se...

Acoustics provides a powerful modality with which to ‘see’ the mechanical properties of a wide range of elastic materials. It is particularly adept at probing soft materials where excellent contrast and propagation distance can be achieved. We have constructed a scanning acoustic microscope capable of mapping the physical microstructure of such materials. We review the general principles of sca...

A dual mode scanning acoustic microscope is investigated, yielding simultaneously images with optical and acoustical contrast. Short laser pulses are used to excite acoustic waves in a sample for the photoacoustic imaging mode. At the same time the pulses irradiate a conical target generating limited diffraction acoustic waves (X-waves) for large depth of field ultrasound imaging. For photoacou...