Acoustic Microscope Lens Optimization for Subsurface Imaging

Abstract

The acoustic microscope image of internal structure of solid sample is complicated by high spherical aberrations, that can limit a penetration depth of a microscope1, and by formation of acoustic waves of different polarizations in the sample body and on the sample surface2,3. A short ultrasonic pulse passed through acoustic lens and reflected by uniform isotropic solid layer split in five pulses due to an ultrasonic wave reflection at surface, Raleigh wave formation on the sample surface4, longitudinal and transverse wave reflection from back surface, and longitudinal to transverse wave conversation on back surface of the sample. In simple case of uniform solid layer the pulses is time resolved, but if investigated body contain discontinuities at different depth the image would complicate by interference of it. It is especially true for high frequency ultrasonic microscope that use a long lasting ultrasonic pulses5.KeywordsLongitudinal WaveReflection CoefficientBack SurfaceConverted WaveAcoustic MicroscopeThese keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.