Graduate Thesis Or Dissertation
 

An underwater acoustic imaging system

Public Deposited

Downloadable Content

Download PDF
https://ir.library.oregonstate.edu/concern/graduate_thesis_or_dissertations/jw827f281

Descriptions

Attribute NameValues
Creator
Abstract
  • An experimental underwater acoustic imaging system has been designed and built. Operating at 650 KHz, real time acoustic images are obtainable. Using both geometrical optics and Fourier optics, the theory of image formation and resolution is presented. Other factors affecting image quality and system acuity are also discussed. System components include a 650 KHz lead-zirconate-titanate (PZT) illuminating transducer, and 01.4 Plexiglas acoustic converging lens, an 81 element mosaic PZT receiving transducer which is resonant at about 650 KHz, 81 amplifiers, a scanning and synchronizing system, and a display oscilloscope. Acoustic energy reflected by the target object is collected by the lens and focused onto the image receiving transducer, which is located in the image plane. The image, appearing as a spatial acoustic pressure distribution in the image plane, is sampled by the 81 element receiver, The 81 image element voltages are amplified and sequentially transmitted to the Z-axis input of an oscilloscope. Each channel amplifier is switched, in sequence, by solid state logic switches located in the scanning circuit. The scanning circuit drives the oscilloscope in a nine line TV type raster scan. If an image element is insonified, a bright spot corresponding to the image element is lighted on the oscilloscope display. The receiving system has a measured sensitivity threshold of 3 x 10⁻¹⁰ watts/cm² and a measured system resolution of approximately 2. 1°. Real time images of simple styrofoam targets are displayed.
Resource Type
Date Available
Date Issued
Degree Level
Degree Name
Degree Field
Degree Grantor
Commencement Year
Advisor
Academic Affiliation
Non-Academic Affiliation
Subject
Rights Statement
Publisher
Peer Reviewed
Language
Digitization Specifications
  • File scanned at 300 ppi (Monochrome, 8-bit Grayscale) using ScandAll PRO 1.8.1 on a Fi-6670 in PDF format. CVista PdfCompressor 4.0 was used for pdf compression and textual OCR.
Replaces

Relationships

Parents:

This work has no parents.

In Collection:

Items

Thumbnail Title Date Uploaded Visibility Actions
file details KolarMichaelJ1971.pdf 2017-08-07 Public Download