Acoustical Imaging

ISBN-13: 9781461397823 / Angielski / Miękka / 2012 / 776 str.

Eric Ash

Opis

The formation of images by ultrasound is a fascinating study, with well-established, yet rapidly growing, applic- ations in medicine and with increasing relevance to a surprisingly disparate set of problems in the non-destructive examination of materials and components. The present volume is a record of the research presented at the Twelfth International Symposium on Acoustic Imaging, held in London during July 1982. Whilst, therefore, it offers primarily a snap-shot in time of a rapidly developing field, it is so organized that it will also serve as a high-speed entry into the literature for someone embarking, for the first time, on- researches in this branch of applied science. As in previous volumes, some of the work reported is concerned with topics which, whilst of critical importance to the performance of any imaging system, - e.g. transducers, signal processing may not address themselves to image formation per se. A new departure is the inclusion of photo-acoustic imaging a subject of rapidly growing importance for many of the same application areas relevant to acoustical imaging.

Spis treści

Acoustical Microscopy — 1.- Considerations of Contrast in the Helium Acoustic Microscope.- Acoustic Microscopy at Temperatures Less Than 0.2°K.- Planar Acoustic Microscope Lens.- Acoustical Microscopy — 2.- Coverslip Induced Artifacts in High Resolution Scanning Laser Acoustic Microscope Images.- Ultrasonic Focussing in Absorptive Fluids.- Scanning Photoacoustic Microscopy and Detection of Subsurface Structure.- Applications of Acoustic Microscopy in the Semiconductor Industry.- Non-Destructive Evaluation — 1.- Application of Scanning Acoustic Microscope to the Study of Fracture and Wear.- Acoustic Microscopy for Materials Studies.- Material Characterization by Acoustic Microscope with Line-Focus Beam.- NDE of Solids with a Mechanically B-Scanned Acoustic Microscope.- Scanning Acoustic Microscopy Inside Ceramic Samples.- Non-Destructive Evaluation — 2.- Ultrasonic-Wave Generation by Surface and Bulk Heating in Multimaterial Structures.- Scanned Photothermal Imaging of Subsurface Structure.- Acoustical Imaging of Near Surface Properties at the Rayleigh Critical Angle.- An Experimental Investigation of the ‘Hosepipe’ Technique of Real-Time C-Scanning.- Signal Processing — 1.- A Stochastical Imaging Procedure.- Lateral Inverse Filtering of Ultrasonic B-Scan Images.- Texture Classification of B-Scan Ultrasound Images: an Assessment using Tissue Models.- Reduction of Speckle in Ultrasound B-Scans by Digital Processing.- Signal Processing — 2.- Optical Processing of Linear Array Ultrasonic Images.- Inverse Filtering to Minimize the Effect of Mechanical Aberration in Focusing Piezoelectric Transducers.- The Application of Maximum Entropy to the Processing of Ultrasonic Images of Nuclear Reactor Components Immersed in Liquid Sodium.- A Self-Focusing Ultrasonic Image Reconstruction Technique.- New Possibilities in Data Measurement, Signal Processing and Information Extraction; Philosophy and Results.- Transducers — 1.- A Method for Improving Acoustic Switching Ratio in Opto-Acoustic Transducers.- The Design of Electric Excitations for the Formation of Desired Temporal Responses of Highly Efficient Transducers.- A Linear Monolithic Receiving Array of PVDF Tranducers for Transmission Cameras.- Physical Limiations of Optically-Scanned Acoustic Imaging Tranducers at Ultrasonic Frequencies Above 10MHz.- Transducers — 2.- Particle Velocity and Displacement Patterns of Disc Transducers with Amplitude Shading.- Recent Developments in Axicon Imaging.- Multi Element Arrays.- Enhanced Trapped Energy Mode Array Transducer Using Thickness Overtones.- A Theoretical Study of Transient Behaviour of Ultrasonic Transducers in Linear Arrays.- An Experimental Method for Characterizing Ultrasonic Transducers.- A Two-Dimensional Phased Array with an Extended Depth of Focus: Some Preliminary Results.- Scattering and Propagation.- Estimation of Echo Scattered from Strongly Scattering Medium.- Directivity Patterns in Inhomogeneous Acoustic Media.- Tissue Ultrasonic Attenuation Well Modelized by a Mellin-Convolution.- Three-Dimensional Imaging of Soft Tissue with Dispersive Attenuation.- Elastic Wave Imaging with the Aid of an Inversion Transformation.- Numerical Techniques for the Inverse Acoustical Scattering Problem in Layered Media.- Tissue Characterisation and Doppler — 1.- Pulse and Impulse Response in Human Tissues.- Two-Dimensional Diffraction Scanning of Both Fresh and Fixed Normal and Cancerous Human Hepatic Tissue.- An Approach to Tissue Characterization Based on Wave Theory Using a New Velocity Analysis Technique.- Short Time Fourier Analysis and Diffraction Effect in Biological Tissue Characterization.- Tissue Characterisation Using Acoustic Microscopy.- Tissue Characterisation and Doppler — 2.- Ultrasonic Doppler Vessel Imaging in the Diagnosis of Arterial Disease.- Real-Time Two-Dimensional Blood Flow Imaging Using a Doppler Ultrasound Array.- Measurement of Blood Flow Using Ultrasound.- Large Area Doppler Array for the Rapid Investigation of the Breast.- Reconstruction Tomography.- Ultrasound Computerized Tomography Using Transmission and Reflection Mode: Application to Medical Diagnosis.- Synthetic Aperture Tomographic Imaging for Ultrasonic Diagnostics.- A Clinical Prototype Ultrasonic Transmission Tomographic Scanner.- Ultrasonic Tomography for Differential Thermography.- Further Results on Diffraction Tomography Using Rytov's Approximation.- A Backward Projection Algorithm Which Corrects for Object Motion in a Scanning Acoustical Imaging System.- Imaging Systems — 1.- 3-D Active Incoherent Ultrasonic Imaging.- Acoustical Imaging Using the Phase of Echo Waveforms.- NDE Imaging with Multielement Arrays.- Imaging Systems — 2.- Acoustical Holographic Scanners.- Second Time Around Echo Immunity from Pseudo Stereoscopic Holographic Imaging.- UHB Imaging.- Expansion of Acoustic Hologram Apertures Using ARMA Modelling Techniques.- Array Systems for Underwater Viewing by Acoustical Holography.- Imaging Systems — 3.- Acoustic Determination of Sub-Bottom Density Profiles Using a Parametric Sound Source.- Abnormal Backscattering off Low Roughness Surface of Metallic Object Immersed in Water.- List of Participants.