Use this URL to cite or link to this record in EThOS: http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.458399
Title: Solid state ultrasonic imaging
Author: Harrold, Stephen Oliver
Awarding Body: University of Warwick
Current Institution: University of Warwick
Date of Award: 1974
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Abstract:
The development and performance of a transistor scanned solid state ultrasonic image converter are described and the results of investigations into various applicable signal processing techniques to produce visible pictures are presented, The general requirements of an ultrasonic imaging system are considered and this is followed by a critical survey of the more sensitive ultrasonic image conversion methods. The operation and basic performance of the transistor scanned converter are discussed and its resolution and sensitivity investigated , resulting in an apparent practical limit to the resolution in. the image plane of ⅓ mm, and an estimated limiting sensitivity of approximately 10-13 W cm-2. Possible methods for the fabrication of a multielement converter are suggested and discussed. Three signal processing techniques are investigated and compared; ;that using an acoustic lens in a conventional camera arrangement, an on-line computer which effectively performs electrically the function of a lens, and a scanned array Doppler system on which only a feasibility study was carried out. It is argued that if flexibility is important then the computer "lens" is the most fitting method, and results for both near field focusing and far field beam deflection are presented) although at the moment.in 1-dimension only , A relatively simple extension to the program will make 2-dimensional image reconstruction possible.. The Doppler system described provides a simple electrical method of determining the range and bearing of far field targets and results adequately confirm the developed theory.
Supervisor: Not available Sponsor: Science Research Council
Qualification Name: Thesis (Ph.D.) Qualification Level: Doctoral
EThOS ID: uk.bl.ethos.458399  DOI: Not available
Keywords: TK Electrical engineering. Electronics Nuclear engineering
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