New Methods of Ultrasonoscopy and Ultrasonography

Abstract

Four groups of new methods of indirect ultrasonoscopy and ultrasonography are developed: those using temperature-sensitive chromotropic compounds, those using leucobases of dyes, those using thermo-stimulable phosphors, and those using special temperature-sensitive phosphors. Various techniques are described and some results shown in the illustrations. Finally, a new method of direct ultrasonography is proposed. This method makes use of the possibility to detonate certain labile chemical compounds by ultrasonics.N the ultrasonographic investigations, on which the first named author • reported in a previous issue of the Journal, serious difficulties arose from the heat developed in the ultrasonic field unless careful precautions were taken. Therefore, it was very natural to try whether methods of indirect ultrasonoscopy and/or ultrasonography could be developed with the heat effect as the primary effect. In what follows a concise account is given of a series of successful experiments conducted chiefly although not exclusively along this line and some illustrative results are shown.In Table I the various methods of ultrasonoscopy and ultrasonography discussed in this paper are classified and tentatively named with reference to the recording material. A. CHROMOTROPIC METHODS a. Thermo-Chromotropic MethodIn thermo-chromotropic methods substances are applied which change their colors upon heating. They are designated as temperature-sensitive chromotropic compounds and especially as reversibly-chromotropic, if they possess the property of regaining their original colors on cooling down to their initial temperatures.Among the reversibly-chromotropic compounds used in the experiments under discussion here mercury silver iodide had the greatest temperature-sensitivity. This substance was made according to Rosenberg's 2 direc-* Presented at the 42nd meeting of the Acoustical Society of America, Chicago, October 23, 1951. • This paper represents an essential part of a thesis submitted by the second named author to . The recipe reads translated from German:Dissolve 17 g of silver nitrate in about 150 cm s of distilled water and also 16.6 g of potassium iodide in 150 cm a of distilled water. Mix both solutions well in a flask. Filter off the yellow precipitate of silver iodide, wash it thoroughly on the filter paper with distilled water, and allow both the filter and the residue on it to dry in a dark place. Dissolve 13.6 g of mercuric chloride in about 400 cm 3 of distilled water and add a solution of 16.6 g of potassium iodide in 100 cm s of distilled water. Filter off the deep-red precipitate of mercuric iodide, wash it thoroughly on the filter paper with tions. The preparation was impasted, with nitrocellulose lacquer as a binder, on a sheet of stiff, thin, and glossy drawing paper and allowed to dry. Later a plastic film screen was made which gave better results than the paper screen.The chromotropic screen was irradiated ultrasonically and the hotter parts of the ultrasonic field, such as the focus of a concentration de...

Acoustical Holography

“…Another thermal detection method for ultrasound involves compounds which change color as a function of temperature e, 36,41). Several iodine, chloride, and organic thermal color change materials have been studied (41).…”

“…*Methods for preparing screens are given in (36). tThe very small temperature range possible was brought up during the discussion of (44) at the Fifth International Conference on Nondestructive Testing, Montreal, Canada, May 1967.…”

“…The coefficients an and bn occurring in (36) are obtained from the Fourier expansion for the pressure at y = O. The pressure at the origin is given by p(z,O) = Lan cos(nnz/l) + bn sin(nnz/I) n But it was shown that this distribution is…”

“…The specimen was inserted in the path of one of the beams, to create an ultrasonic hologram at the liquid/air interface. The hologram was illuminated by a monochromatic, quasi-coherent light source, which was reflected from the liquid surface, and diffracted by the interference at the liquid/air interface, Buss, L.,44,277 Carlin,B.,141,142 33,34 Oshchepkov,P.K.,42,46 Palermo, C. T.,101,112 Peterman,L.,36,46,47 Phan,N. V.,42,44,46 Phariseau,P.,154,158 Phase,distortions,[187][188][189][190][191][192][193][194][195][196][197][198][199][200][201] 79,206,207,210,211,245,246 Thuras,A.…”