US2528725A

US2528725A - Sound ranging system

Info

Publication number: US2528725A
Application number: US597281A
Authority: US
Inventors: Rines Robert Harvey
Original assignee: Individual
Current assignee: Individual
Priority date: 1945-06-02
Filing date: 1945-06-02
Publication date: 1950-11-07
Anticipated expiration: 1967-11-07

Description

Nov. 7, 1950 R. H. RlNES SOUND RANGING SYSTEM Filed June 2, 1945 AMPLIFIER GENERATOR 056 I LLATOR HORIZONTAL sweep GGNERATOR IN VEA! TOR. Robert H. Ku'les Patented Nov. 7, 1956 U NITED STATES PATENT Gi EFlCE SOUND itANGING SYSTEM Robert Harvey Rin'es, Broolsline', Mass Application J ul'ie 2, 1945, Serial N o.'597',28'1

(o1. list-6.8)

43 Claims; 1

The present invention relates toelectric sys-- tems, and more particularly to receiving systems using, soundwaves .as the agenoyof communication. Theterm sound willbeemployedhereinafter, in the specification and the .claims, to include not only the audible Part of the sound spectrum, but also, andlmore particularly, the.

ultrasonic spectrum, and to include also all kinds of elastic vibrations.

An object of the invention is. to providea new and, improved sound-receiving system.

Another object is to provide a noveljcombined sound-and-television system.

Another object ofv the present invention is to provide a new sound-locator system for both de-, tecti-ng-the presence of a body and producing a visible likeness thereof.

A further, object is to provide a. new rangefinder.

Other and further objects. will be explained hereinafter and will be more particularly pointed out in the appended claims.

The invention will now be. more fully explained in connection with the accompanying drawing, the single. figure of which is a diagrammatic view ofcircuits and apparatus arranged and constructed in accordance with a preferred embodi mentthereof.

A directive ultrasonic transmitter is shown comprising ultrasonic oscillator I05 fo exciting a piezo-electric crystal II]! and an auxiliary reflector' l03 for reflecting the energy emitted by" the piezo-electric crystal Nil upon a parabolic sound reflector l. propagated toward an object 3, illustrated as an underwater submarine. The sound waves are reanyrother type of well-known. lens, mirror or. other directive system for focusing the-sounds waves scatteredandsreflected from the object 3 on the bank or array ZGbf pick-up elements.

The sound lens may, for. example, be constituted.

of-r-alcollodion balloon filledwith carbondioxide orasulphur dioxide; or. anyothersubstanceforrefractingthe sound waves Ultrasonic waves are thusmember 9.

V The crystal :piok-up; -units are; shown all electrically -poled inthesame; mannerv and arranged in-the form of rows and columns,.in -the roximity, of the focalplaneof-the lens. 5. The first. or. uppermost row of-thebank is illustrated as comeprising-thegroup-of:crystalsa; 23, 21, 21, |9, l1,- l5, l3 and H, shown'as equally'spaced horizonv tally.- ThBSGCOIldI'IOW from the top is shown constituted of a group of similarly disposed crys-- tals, respectively: disposed directlybelow the cor responding ycrystalsof the fixatrow; severalofi these areillustratedat 29; 3I- and 33. ThB thiIdiS or next-lower row is similarly constituted, several ofthecrystals beingillustrated at 35-and 31. Though .onlyaismall. number of pick-up units is shown in each row,z-and: though only three .rows are shown, thisiismerelyrfor illustrative purposes; in order-no.t:toaconfuse,thedisclosure: It will be understood that, in practice; a. large. number Y of pick-up. units will be employed in each row.

The 1 crystal elements 2 5 2 9,: 35, etc are shown equally-spaced. vertically in the firstor right-hand: column; The.crystahelements;1123,1 3t, 31, etc.-,- 7 are disposed imthe. secondcolumn from the right. The crystal elements 21;: 33,.ietc.,. are; disposed inii the .third .columnufromzithej: right. and. so 011.11.. There may, or maynotgbe as manycolumns-as= there are pick-upunitspinleach row. Though;- each column is shown as compri g y. a few? pick-upunits, this. 'is=.,againin ordermot to com-n plicate thedrawing. V

The; pickeupi units will; ofjcoursagallreceiverthe-reflected or scattered s-oundwaves through thewlense 5 simultaneously. There will be fo-. cused on the front surface of each pick-up unit. a sound-wave intensitycorresponding to'the intensity of the sound energyreflected or scattered from a. corresponding component part, portion 2 or area oftheobject 3. Each pick-up unit willvibrate individually and separately in response tothesound waves impinged upon it. Electricwave energy, alternatingecurrent voltages will thus be translated, produced or generated across the pick-up elements corresponding to the different field strengths of sound-wave energy thus received by them. Since the piezo-electric effect is linear, these voltages will be proportional to the intensity of the sound-wave .energy reflected or scattered or otherwise emanating from the various component portions of the object 3 and converged upon the array 26 of pick-up elements by the lens 5. The sound lens 5 or its equivalent will thus focus upon the array 26 the sound Waves reflected or scattered from the various component portions of the object 3 in various energy strengths dependent on the reflecting properties of the component parts of the object -3, thus to produce a faithful sound image of this distribution of the sound waves in approximately the focal plane of the lens 5. The same result may be attained, as first pointed out by Lord Rayleigh, with the aid of a circular disc (not shown) the sound waves from the object will become diffracted about the periphery of the disc to produce a similar sound image of the object 3.- It has heretofore been [proposed to convert a soundenergy picture of this character into a visiblepicture likeness I23 of the object 3 upon the fluorescent viewing screen 30 of a display cathode-ray oscilloscope tube 90. The tube 90, as well as the cathode-ray-oscilloscope-like member =9, is shown operating on the electrostatic principle, but, of course, a magnetic deflector, or a combination of magnetic and electrostatic forces, may equally well be employed in both the tube 90 and the tube 9. Improved results may be obtained, however, in accordance with a feature of the present invention, with the aid of a load circuit in which may appear the totality or resultant of the voltages produced by all the soundwave receiving elements in response to the impingement of sound waves thereupon. This resultant voltage may then be diminished by successive quantities dependent upon the soundwave energy impinged upon the successively disposed sound-wave receiving elements, thereby to effect a scan of the distribution of sound waves impinged upon the elements.

The crystals l3, I5, etc. may be held in metallic crystal holders. The crystal II, for example, is illustrated as disposed between a pair of metal electrodes 4| and 5|, and the crystal I3,

between a pair of metal electrodes 45 and 53. Adjacently disposed electrodes of adjacently disposed crystals are shown electrically connected together. The electrode 5| of the crystal II, for example, is shown electrically connected to the adjacently disposed electrode 45 of the adjacently disposed crystal I3. the end crystal of each row, moreover, is shown electrically connected, as at 28 and 32, to the terminal electrode of the corresponding crystal of the next row. The crystals are thus all connected together in series relation with a source of energy, shown as a battery 2, one of the func-' tions of which is to sensitize the vibratory response of the crystals, and a load impedance 4.

There will thus be produced across the load impedance 3 a voltage dependent upon the sum of the alternating-current voltages produced across the individual crystals by the incident sound waves and the direct-current-biasing voltage of the battery 2. Provision is made, however, for short-circuiting successively disposed crystals, thus to develop or produce successively across the impedance 4 fluctuating current or voltage signals or indications corresponding to the voltage drops across the successively disposed crystals and, therefore, to the corresponding strengths of sound-wave energy received by the crystals.

According to a further feature of the present invention, this short-circuiting or scanning process is effected with the aid of a scanning electron stream in the cathode-ray-oscilloscope-like member 9, which is shown provided with a vacuum-tube, electron gun comprising a, cathode 6, a control-grid electrode 8 and an anode ID. This obviates the necessity for mechanically moving parts or other complex scanning mechanisms and permits the use of common scanningvoltage ecircuits for effecting both the scan of the sound-wave receiving elements and the scan of the electron stream of the display cathode-ray tube, as hereinafter explained. Electrons emitted from the cathode 5 will become accelerated, in response to proper stimulation of the grid 8, so as to pass by the grid 8 to the anode II) of the member 9. The electrons will continue to travel in a stream fromthe-anode I0, between a pair of vertically disposed deflector plates I6 and I8, of which the plate I8 is shown grounded, and between a pair of horizontally disposed deflector plates I2 and I l, of which the plate I4 is shown grounded, to impinge finally on the disc I of the member 9. A horizontal-sweep-time base, applied to the vertically disposed deflector plates I6 and I8, will cause the electron stream from the cathode 6 to become deflected horizontally as many times as there are rows of pick-up elements.

-- After each horizontal sweep or scan of the cathode-ray or oscilloscope-like member 9 has been .,,sweep-time base causing the electron stream to become deflected vertically, and causing each of the horizontal sweeps to appear at successively v lower levels on the face I corresponding to successively lower vertically disposed levels of the rows of elements. The rows of crystals may be The terminal electrode of positioned along the successive paths of the electron stream, as the electron stream successively sweeps or scans the successive rows of the array on thedisc I. After the last such horizontal sweep, the horizontally disposed plates of the member 9 will become restored to their starting voltage. The next horizontal sweep, therefore, will start again at the first or top row. Sweep or scan-

voltage generators

20 and 22 may be employed to produce the horizontal-time-base sweep and the vertical sweep, according to conventional and well-known television techniques.

The distance or spacing between the electrodes of'each crystal, such as the electrodes 4! and 5| 0f the crystal I, may be made of value necessary to give a desired capacitance to provide a circuit resonant to the frequency of the received sound waves, thereby further to enhance the mechanical vibrations of the crystals, and the anode I0 may be adjusted so that the distance between the pair of electrodes of each crystal shall be equal to the width of the electron stream. The electron stream will thus become enabled to fill the gap between the electrodes of each crystal, thereby discharging the capacity between these electrodes.

As the electron stream produced from the oath 1 ode 6, in response to appropriate horizontal sWeep-time-base voltages applied to the vertically disposed deflector plates I6 and I8 of the cathode ray-like member 9, travel across between the ass-ares crystai electrodes, th'e voltages-built upfacross. the

pli'fier 24. This amplifier 24 is operated at a high point on its characteristic curve by virtue of the bias battery 2 in series with the small alternating voltages from the crystals across the'input of the amplifier. The positive swings of the alternatingv voltages from-the crystals drive thetub'e '25 into thesaturation region, Whilethe negative swings" are' amplified on the linear characteristic, thus producingpositive pulses at the-plate or anode of the-amplifier-2d Operating, in this manner,

as an overdrivenamplifier; it serves, therefore, as

a rectifier.

Upon" the successive short-circuiting of each crystal-condenser element by the electron stream, as discussedabove, the alternating voltage across the impedance 4 is diminished by the small voltage from the particular crystal element representative of-the intensity of the sound wave impinged on that element. The amplified positive pulses-occurring in the output of the amplifier 24, during the scanning of a crystal, therefore, will have a peak amplitude that is less than before by an amount equal to the amplification of the tube multiplied by'the voltage appearing across the particular crystal element. The output of the amplifier 2% will thus obviously vary, at successive instants, in accordance with the discharge or short-circuiting of the successive crystals, which discharge, as before stated, is a measure of the, strength of the sound energy received by the corresponding pick-upelements.

Means is provided, controlled by the discharge or short-circuiting of the crystal electrodes, for producing, upon the screen .30 of the display oscilloscope 90, image I23 corresponding to the sound energy received by the corresponding pickup elements. successively disposed parts, portions, regions or areas of the screen at, that correspond .to thesimilarly disposed pick-up .elements, are energized by an electron stream in the oscilloscope 98 to illuminate them. This electron stream is synchronized to travel with the electron stream of the cathode-ray-like member 9. The horizontal sweep circuit 26 is shown connected tothe horizontal-deflector plate I I6 of the oscilloscope 9B, and to the horizontal deflector plate l6 of the oscilloscope-like member 9. The verticalsweep circuit 22 is shown connected to the vertical-deflector plate! iz of the oscilloscope 9t and to the vertical-deflector plate I2 of the oscilloscope-like member 9, The other horizontal-deflector plate ;I I8 and the othervertical-defiector plate; lI4-- of the oscilloscope 90 are shown grounded.

Thevamplifier 2% is shown connected by a conductor 36 to the control-grid electrode 8! and by a conductor 3e to=the cathode d8 of the oathode-ray oscilloscope 9t]; Electrons emitted from loscopeldeflector plates..-ll5 and I I8, and betweenthelpair. of horizontalyis disposed oscilloscope dee flectorplates H2 and I It, to impinge finally on? the iiuorescent viewing screen 30 of the oscillo-' scope 90. As previously described in connection with the oscilloscope-like member 9, the horizontal-sweep-time base, applied to the vertically disposed defiector plates H6 and H8, will cause the electron stream from the cathode to become deflected horizontally, and the vertical-sweeptime base, applied to the horizontally disposed deflector plates H2 and Ht, will cause the electron stream to become deflected vertically.

Since the cathode-ray tubes 9 and 9B are subjected to the-same scanning voltages, the electron stream in the tube Elev/ill impinge on the fluorescent screen as in synchronism with the electronstreamimpinging on the crystals on the face i of the oscilloscope-like member 9 during the voltage-discharging or scanning process. The signals amplified by the amplifier 2 3, and fed between the cathode 69 and the control electrode 80, will produce intensity modulation of the beam impinging on the screen 39. Prior to the discharging process, positive swings or pulse outputs of the amplifier 2 would make the cathode 6i! periodically positive with respect to the grid at. In conjunction with the bias of a battery 38 disposed between the cathode 6G and the grid this would permit the passage of but few of the electrons of the electron stream beyond the grid 83. Since, during the discharge of a crystal element, however, the positive swings or pulses in the output of the amplifier 24 are of a peak amplitude less than the original pulses by an amount pportional to the voltage produced by the sound waves across the particular crystal element, the cathode is periodically driven less positive with respect to the grid 83. A larger quantity of electrons are thus permitted to travel periodically past the anode H33, during the train of pulses produced by a crystal-condenser discharge, to impinge finally on the fluorescent screen 539. The quantity of electrons that reach the screen 39 to produce intensity modulation during the scanning of a particular crystal, therefore, depends on the decrease in the output of the amplifier E i, and this, in turn, depends upon the voltage produced across the crystal by the sound-wave intensity impinged thereon. The electromagnetic illumination resulting from the intensity of modulation on the screen 3! will be such that the intensity of illumination of parts of the screen 39 corresponding to parts of the crystal hank 25 will correspond to the soundwave image on the rows and columns of the bank 25; this sound-wave image, in turn, corresponding to correspondingly disposed parts of the object 3.

To each row of crystals, therefore, there correspends, on the face '5 of the oscilloscope-like member .S, a horizontal electron stream that discharges the crystals of that row. To the sound distribution on each row of crystals, moreover, there corresponds, on the oscilloscope screen 3!], a horizontal electron stream that is graded in intensity. This intensity is, as before stated, distributed in synchronisni with the corresponding state of voltage across the corresponding crystals. of the array 25 of the oscilloscope-like memberfl.

The sound waves received successively by the crystal units along the successive r Ws and columns, as the units are rendered successively effective in the dispiay circuit, Will thus become converted into successive elemental portions of the visual likeness, along correspondingly disposed rows and columns thereof, alongthe suc-.

cssi've' time bases. The elemental portions of the visual-picture likeness I23 of the object 3 thus produced on the oscilloscope screen 30 will accordingly correspond to the elemental portions of the sound energy picture on the array 26 of pick-up elements which, in turn, corresponds to the elemental portions of the actual object 3. A visual image 123 of the object 3 is thus produced on the screen 30.

The crystals of the bank 26 may be wafer thin in order to make possible the use of a sufficiently large number of them in the array 26 to provide for good definition. The frequency of the sound Waves, for example, may be 100 megacycles, corresponding to a wave-length of approximately 5 10 feet, in water, and produced, for example, by an oscillating quartz crystal, as described, for example, in an article by W. P. Mason and I. E. Fair, entitled A New Direct Crystal- Controlled Oscillator for Ultra-Short-Wave Frelquencies, Proceedings of the Institute of Radio Engineers, October, 1942, vol. 30, No. 11, pages 464 to 472; Lower irequencied crystal oscillators may also be used, as described, for example, in an :article by G. W. Pierce, entitled Piezoelectric Crystal Oscillators Applied to the Precision Measurement of the Velocity of Sound in Air and CO2 at High Frequencies, Proceedings of the American Academy of Arts and Sciences, October, 1925, vol. 60, No. 5, pages 275 to 295. Reference may be made also to W. G. Cady, Piezoelectricity, McGraw-Hill, 1946, pp. 501 to 506 and 682, and Kamay-achi and Watanabe, Electrotechnical Journal of Japan, vol. 5, No. 1, 1941 pp. 19 and 20.

According to a further feature of the invention, it is possible to find the range of the object 3, assuming that its size is known. All that is necessary is to adjust the position of the lens 5 so as to produce a sharp sound image on the array 26 of pick-up elements; the range may then be obtained by simple geometrical optics. If, for example, the object 3 is a submarine of known size, the size of the visible likeness H23, divided by the known size of the submarine, will have the same ratio as the ratio between the distance of the lens 5 from the bank 26 of pickup elements, adjusted to obtain clear vision, di vided by the distance of the object '3.

Although the invention has been described in connection with pick-up elements arranged in rows and columns, it will be understood that this is not essential, for other arrangements are also possible. Pick-up elements arranged along concentric circles covering the field, or along a continuous spiral, will also serve, though the oscilloscope arrangement would, of course, be correspondingly modified.

Further modifications will occur to persons skilled in the art, and all such are considered to :fall within the spirit and scope of the invention, as defined in the appended claims.

What is claimed is:

1. An electric system having, in combination, a bank of piezo-electric sound-receiving elements, means for focusing sound waves from an object upon the sound-receiving elements, a load circuit, means for permanently connecting the bank of receiving elements to the load circuit, means for scanning the receiving elements to develop signals in the load circuit representative of the sound-wave energy focused upon the receiving elements, and means operating in synchronism with the scanning means and responsive to the signals developed in the load circuit for producing a likeness of the object.

2. An electric system having, in combination,- a bank of sound-receiving elements, means for focusing sound waves from an object upon the sound-receiving elements, electron-beam scanning means associated with the receiving elements for successively scanning the elements to develop successive signals, and cathode-ray-oscilloscope means acting in synchronism with said scanning means and controlled in accordance with the signals for producing a likeness of the object.

3. An electric system having, in combination, a plurality of sound-receiving elements each capable of developing a voltage in response to received sound-wave energy, means for impressing sound waves upon the elements to develop a voltage upon each element, means for successively discharging the voltages, and means controlled by and synchronously with the discharge of the voltages for producing a likeness corresponding to the energy received by the corresponding element.

4. An electric system having, in combination, a plurality of sound-receiving elements each capable of developing a voltage in response to received sound-wave ener y, means for impressing sound waves upon the elements to develop a voltage upon each element, means for successively discharging the voltages, a screen successively disposed areas of which correspond to the successively disposed elements, and means controlled by and synchronously with the discharge of each voltage for energizing the area corresponding to the corresponding element.

5. An electric system having, in combination,

a plurality of sound-receiving elements each capable of developing a voltage in response to received sound-wave energy, means for impressing sound waves upon the elements to develop a voltage upon each element, means for successively discharging the voltages, an oscilloscope having a screen successively disposed areas of which correspond to the successively disposed elements, and means for sending an electron stream through the oscilloscope in synchronism with the discharge of the voltages to illuminate the areas in synchronism with the reception of the sound energy received by the corresponding elements.

6. An electric system having, in combination, a plurality of sound-receiving elements each capable of developing a voltage in response to received sound-Wave energy, means for impressing sound waves upon the elements to develop a voltage upon each element, means for sending an electron stream to the elements successively to discharge them, an oscilloscope having a screen successively disposed areas of which correspond to the successively disposed elements, and means for sending an electron stream through the oscilloscope in synchronism with the first-named stream and for controlling the electron stream in accordance with the discharge of the elements to illuminate the areas in synchronism with the reception of the sound energy by the corresponding elements.

7. An electric system having, in combination, a plurality of sound-receiving elements capable of responding electrically when mechanically vibrated by sound waves from an object, each sound-receiving element corresponding to a predetermined elemental portion of the object from which it receives sound waves, means for producing scanning voltages, means responsive to the scanning voltages for scanning the successive sound-receiving elements thereby to scan the sound Waves received from the object, and means responsive to the Scanning voltages and controlled "by the electrical response of the successive sound- :receiving elements produced when mechanically vibrated by the sound Waves received from the correspondin predetermined elemental portions of the object to produce a likeness of the corresponding successiveelemental portions of the object.

8. An electric systemfhaving, in combination, a cathode-ray apparatus comprising means for producing an electron stream, a mosaic provided with .a plurality of groups of piezo-electric elements substantially equally spaced alongar predetermined dimension, with the piezo-electric elements of each group substantially equally spaced along a second predetermined dimension, the piezo-electric elements being mounted to vibrate individually and separately in "response to sound waves impinging upon the respective piezo-electric elements, means for causing the'electron'stream .to impinge upon the piezo-electric elements, and means controlled. synchronously with and responsive to the impingement of the electron -stream upon the piezoelectric elements for pro ducing a likeness corresponding to the received sound waves.

' 9. An electric system having, in'combination,

" a cathode-ray apparatus comprising means for producing an electron stream, a mosaic provided with'a'plurality of groupsof piezo-electric elements substantially-equally spaced along-a predetermined dimension, with the piezo-electric elements of each group substantially equally spaced along a second predetermined-dimension, the

piezo-electric elements being mounted to vibrate individually and separately in response to sound waves impinging upon the respective piezo-electric elements, means for causin the electron stream to'scan successively the successive piezoelectric elements of eachsuccessive-group of piezoelectric elements, an image-reproducing means, and means operating synchronously with the scanning means and responsive to the scanning of the successive piezo-elect'ric elementsrafor' producing upon the image-reproducingmeans a likeness corresponding to the received sound waves.

10. An electric system having, in combination, 'a cathode-ray apparatus comprising means for producing an electron stream, a mosaic provided with a plurality of multi-surfaced piezo-electric elements forreceiving sound waves from an object, each element being providedwitha pair of electrodes adjacent to two surfaces'of the element, means for causing the electron stream to travel towards the element surfaces unprovided with electrodesin order to scan the piezo-electric elements, and means responsive' to the scanning of the piezo-electric elements and 'controlled synchronously therewith for producing a likeness of the object, t

11. An electric system having, in combination, "a cathode-ray apparatus comprisin meanslfor producing an electron'stream;ai-fmosaic upon which the electron 'stream mayl-impingeprcvided "with a plurality of 'groupsof "piez'o-electri'c elewaves from an obiect'and the rear surfaces of the elements beingexposejd 'to the electron stream Within the cathodeeraywapparatus, 1 means tor causing the-electron stream to scan the rear sur- .-facesof the piezo-electric elements, and means controlled synchronously with the scanning means -a cathode-ray apparatus comprising means for producing an electron stream, a mosaic of piezoelectric elements for receiving sound waves from an object, each element of the mosaic having two electrodes spaceda distance corresponding substantially to'the width of the electron stream,

means for'causi-ng the electron stream to scan the piezo-electric'elements; and means controlled synchronously with the scanning a means and -responsiveto the scanning of the piezo-electric ele- "ments for producing a likeness of the object.

13. An electric system having, in combination, a cathode-ray-apparatus comprising means for producing-an-electron stream, a mosaic upon which the electronstream may impinge provided with-a plurality of groups of piezo-electricele- -ments substantially equally spaced along a predetermineddimensionwith the piezo-electric elements of each group substantially equallyspaced along a second predetermined dimension, the

' piezo-electric elements being mounted to vibrate individually and separately in response to sound waves from an object impinging upon the respective piezo-electric elements, each pieZo-electric element having two electrodes connected in a common electric circuit, means for causing the electron stream to scan the piezo-electric elements in order to produce electrical'signals in the electric circuit and means responsive to the electrical signals and controlled synchronously with the scannin means for producing a likeness of the object.

14. An electric system having, in combination,

a' mosaic comprising a two-dimensional array of sound-receiving elements for receiving sound waves froman object; means for producing an electron stream impinging on the elements, an

' electric circuit in which the elements are con- "cuitjan'd means controlled in synchronismwith the scanning'mea-ns and responsive to the signals in the electric circuit to produce successive portions ofa likeness of the object in two-dimensional order synchronously with the reception of the sound energy from the object by the receiving elements.

15. An electric system having, in combination, a first electron tube having a screen and means for producing'a first electron stream impinging on the screen, a second electron tube having a plurality of "sound-receiving elements for receiving sound energy and'means for producing a second 'electron' stream impinging on the elements, means 'for-synchronizingtheoperation of the electron streams, and means" operable in response to the sound energy received by the sound-receiving elements and cooperative with the second electron stream for causing the first electron stream to produce upon the screen a likeness corresponding totheenergy received by the sound-receiving --elernents.

'16: An electricsystem having, in combination,

sound receivingwmeans the dimensions of which ivary. .in .='resp onse-to the received" sound 'waves,

" means for producing an electron stream impinging'on the sound-receivin means, means for causing the electron stream to scan the soundreceiving means, an electric circuit in which the sound-receiving means is connected, and means for directing sound energy on the sound-receiving means to produce changes in the dimensions of the sound-receiving means, thereby to vary the current in the circuit as the electron stream scans the sound-receiving means,

17. In combination, means for imaging sound waves from a scene to be reproduced, a soundwave pick-up device comprising piezo-electric means, means for producing scanning voltages, means responsive to the seaming voltages for scanning an area successive portions of which correspond to successive portions of the soundwave image, means controlled in accordance with the scannin for converting the energy picked up during the scanning by the pick-up device from the different portions of the image into corresponding electrical signals, a display cathode-ray tube, means responsive to the scanning voltages for operating the tube in synchronism with the scanning, and means for supplying the signals to the tube, whereby a picture of the scene is obtained.

18. In combination, means for imaging sound Waves from a scene to be reproduced, a soundwave pick-up device comprising mechanically vibratory means, means for producing scanning voltages, means responsive to the scanning voltages for scanning an area successive portions of which correspond to successive portions of the sound-wave image, means controlled in accordance with the scanning for converting the energy picked up during the scanning by the pick-up device from the different portions of the image into corresponding electrical signals, an imagereproducing means, means responsive to the scanning voltages for operating the image-reproducing means in synchronism with the scanning, and means for supplying the signals to the imagereproducing means, whereby a picture of the scene is obtained.

19. A system for transforming an image formed by sound Waves into an image formed by electromagnetic waves, said system comprising a plurality of spaced sound-receiving elements each having two conductive surfaces separated by a lar one of said receiving elements in proportion to the sound intensity at the given point, means periodically discharging said receiving elements in succession, thereby producing a fluctuating current varying in accordance with the magnitude of the alternating currents from element to element, and means producing an electromagnetic image from the information carried by the fluctuations in said current.

20. An electric system having, in combination,

"means comprising a plurality of vibratile elements for receiving sound waves from an object, each element bein capable of translating sound waves received by it into electrical waves of intensity corresponding to the intensity of the received sound waves, means for focusing a soundments, a load circuit, means for permanently connecting the plurality of receiving elements to the load circuit to develop electric-wave signals representative of the sound-wave energy focused upon the receiving elements, means for scanning the elements thereby to scan the sound-wave image, and means connected to the load circuit operating in synchronism with the scanning and responsive to the electric-wave signals translated from the received sound waves by the receiving elements and developed in the load circuit for producing a likeness of the object.

21. An electric system having, in combination, a plurality of sound-receiving elements for receiving sound waves from an object, each element being capable of translating sound waves received by it into corresponding electric energy, a load circuit, means for connecting the plurality of receiving elements to the load circuit simultaneously to produce electric energy in the load circuit representing the resultant of the electric energy produced by all of the plurality of receiving elements, means for instantaneously diminishing said resultant of the electric energy by quantities corresponding to the electric energy translated by the successive sound-receiving elements from the sound waves received thereby, and means operating synchronously with the diminishing means connected to the load circuit and responsive to the electric waves for producing a likeness of the object.

22. An electric system having, in combination, a plurality of vibratile means for receiving sound waves and translating the received sound waves into corresponding electric energy, means for focusing sound waves from an object upon the sound-wave receiving means, a load circuit comprising an amplifier, means for producing a biasing voltage, means for permanently connecting the biasing-voltage-producing means and the sound-Wave receiving means to the load circuit, and means connected to the amplifier and responsive to the electric energy translated from the received sound Waves by the receiving means for producing a likeness of the object.

23. An electric system having, in combination, sound-energy receiving means capable of respondin electrically in response to sound energy received thereby, means for producing electrons for varying the electrical response of the soundenergy receiving means thereby to develop a signal, and means controlled by the signal for producing an indication corresponding to the sound energy received by the sound-energy receiving means.

24. An electric system having, in combination, mechanically vibratory means adapted to be set into mechanical vibration in response to sound energy impinging thereon and capable of responding electrically when vibrated mechanically, means for producing electrons for varying the electrical response of the mechanically vibratory means when vibrated mechanically thereby to develop a signal, and means controlled by the signal for producing an indication corresponding to the sound energy impinged upon the mechanically vibratory means.

25. An electric system having, in combination, mechanically vibratory means adapted to be set into mechanical vibration in response to sound energy impingin thereon and capable of responding electrically when vibrated mechanically, means for impinging electrons upon the mechanically vibratory means to vary the elec- 13 tricalresponse of the mechanically vibratory means when vibrated mechanically thereby to -develop-a signal, and means controlled by the signal for producing an indication corresponding actoithe sound energy impinged upon the mechanically vibratory means.

26. An electric system having, in combination, 'a plurality of mechanically vibratory means adapted: to be set into mechanical vibration in response to sound energy impingin thereon and capable of responding electrically when vibrated mechanically, means comprising an electron stream for scanning the mechanically vibratory means to vary the electrical response of the mechanically vibratory means when vibrated mechanically thereby to develop successive signals, and means controlled in accordance with the signals and synchronously with the scanning efiected by the scanning means for producing an indication corresponding to the sound energy gimpinged upon the mechanically vibratory ,means.

:2'7. Anelectric system having, in combination, .a plurality of mechanically vibratory means "adapted to be set into mechanical vibration in IIBSPOIISB to sound waves impinging thereon and capable of responding electrically when vibrated imechanically, means for converging sound energy emanating from an object upon the 'mechanically vibratory means to set the me-hchanically vibratory means into mechanical vibration, means comprising an electron stream .;-for scanning the mechanically vibratory means to vary the electrical response of the mechanically vibratory means when vibrated meehani i cally thereby to develop successive signals, and means controlled in accordance with the signals and-synchronously with the scanning effected :by the scanning means for producing a likeness of the object.

'23. An electric system having, in combination, "a plurality of piezoelectric means, means for converging sound energy emanating from an object upon the piezoelectric means to set the piezoelectric means into mechanical vibration; means comprising an electron stream for scanning the :piezoelectric means to vary the electrical re- ;sponse of the piezoelectric means when vibrated -mechanically thereby to develop successive sighala -and means controlled in accordance with the signals and synchronously with the scanning produced by the scanning means for producing a likeness of the object.

29. An electric system having, in combination, J: a plurality of mechanically vibratory. sound-retceiving elements each adapted to be set into mechanical vibration in'response tosound energy impinging thereon and each capable of respondingelectrically when vibrated mechanically, --'..means for converging sound energy emanating ":from an object upon the mechanically vibratory elementsto set the mechanically vibratory elements into mechanical vibration, means com- :prising an electron stream for successively scanningithe mechanically vibratory elements successively to vary the electrical response of the mechanically vibratory elements when vibrated mechanically thereby to develop successive signals, and means controlled in accordance with thesigna1s and synchronously with the scanning effected by the scanning means forproducing a .;likeness of the object.

' 30. An electric system having, in combination, -.:ia;plur.ality of piezoelectric sound-receiving elen; ments';::means for converging sound energygemanating from an :objectupon the piezoelectric elements toset the piezoelectric elements into mechanical vibration, means comprising an .electron stream for successively scanning the..piezo- 5 :electric elements thereby to developssuccessive signals, and means controlled inac'cordance with the signals .and synchronouslyiwith the scanning eifected by the-scanning means for producing a i likeness of the object.

31. An electric system having,:in combination, a plurality of mechanically vibratory imeans adapted to be set into mechanical vibration .in response tosound waves impinging thereonrand capable of responding electrically whenvibrated mechanically, means for converging SOlll'l'dfBIlBI- gy emanating from an object upon the mechani- -ca1ly vibratory means to set the mechanically vibratory means into mechanical vibration, means comprising an electron stream for scannin the mechanically vibratory means to vary the electrical response of the mechanically vibratory means when vibrated mechanicallythereby -to develop successive signals, a cathode-ray oscilloscope having a screen and means. for producing an electron stream for scanning I the screen, and means controlled in accordance with the signals and synchronously with the scanning e-fiected by the scanning means for con- 'trolling the scanning operation of the electron stream of the oscilloscope to produce aslikeness of the object upon the screen. 532. An electric system having, in combination, a plurality of piezo-electric means, means for converging sound energy emanating from an ob- 'ject upon the piezoelectric means to :set the piezoelectric means into mechanical vibration, means comprising an electron stream'for effectin 'the scanning of the piezoelectric'means'to 'vary the electrical response of the piezoelectric means when-vibrated mechanically thereby to develop successive signals, a cathode-ray oscil- "loscope having a screen and means ior'produc- "ing an electron stream for scanning the-screen, and means controlled in accordance with the signals and synchronously with the scanning effected by the'first-named scanning means for controlling the scanning operation of the electron stream of the oscilloscope to produce alikeness of theobject upon the screen.

33. An electric system having, in combination, a, plurality of mechanically vibratory elements each adaptedto be set into mechanical vibration in response to sound energy impinging thereon and each capableof responding-elecstrically when vibratedmechanically, means for converging sound energy emanating from an object upon the mechanically vibratory elements to set the mechanically vibratory elements intomechanical vibration, means comprisinglan electron stream for successivel scanningv the soundreceiving elements successively to vary the electrical response of the mechanically vibratory elements when vibrated mechanically thereby to develop successive signals, a cathode-ray oscilloscope having a, screen and means for produc ing an electron stream for scanning the screen, and means controlledin accordance'with the signals and synchronously with the scanning effected by the scanning means for controlling the scanning operation of the electron stream of :the oscilloscope to produce a likeness of the object upon the screen.

.34.,An electric system having, in combination, lsnazeplura'lityuof piezoelectric soundereceiving ele- 15 ments, means for converging sound energy emanating from an object upon the piezoelectric elements to set the piezoelectric elements into a mechanical vibration, means comprising an electron stream for successively scanning the piezoelectric elements thereby to develop successive .signals, a cathode-ray oscilloscope having a screen and means for producing an electron stream for scanning the screen, and means controlled in accordance with the signals and synchronously with the scanning efiected by the scanning means for controlling the scannin operation of the electron stream of the oscilloscope to produce a likeness of the object upon the screen.

35. An electric system having, in combination, a plurality of mechanically vibratory means adapted to be set into mechanical vibration in response to sound energy impinging thereon and capable of responding electrically when vibrated mechanically, means for converging sound energy emanating from an object upon the mechanically vibratory means to set the mechanically vibratory means into mechanical vibration, a load circuit, means for permanently connecting the mechanically vibratory means to the load circuit, means for scanning the mechanically vibratory means to develop in the load circuit signals representative of the sound energy converged upon the mechanically vibratory means, and means connected to the load circuit and responsive to the signals developed therein for producing a likeness of the object.

36. An electric system having, in combination, a plurality of piezoelectric sound-receiving elements, means for converging sound energy emanating from an object upon the piezo-electric elements to set the piezo-electric elements into mechanical vibration, a load circuit, means for connecting all the plurality of piezo-electric ,"elements to the load circuit simultaneously to produce electric energy in the load circuit representing the resultant of the electric energy produced by all the piezo-electric elements, means comprising an electron stream for successively scanning piezo-electric elements in order to diminish the said resultant of the electric energy during the scanning of the respective piezo-electric elements by quantities corresponding to the sound energy converged upon them by the converging means from the object, and means operable synchronously with the diminishing means connected to the load circuit for producing a elements to set the piezoelectric elements into mechanical vibration each with an intensity corresponding to the intensity of the sound energy emanating from the component part of the object from which the sound energy impinging thereon emanates, means for enhancing the mechanical vibration set up in the piezoelectric elements, means for scanning the successive piezoelectric elements thereby to develop corresponding signals, and means operable as each piezoelectric element is scanned for producing, in a region corresponding to the component part of the object from which the sound-energy impinging on such piezoelectric element emanates, in response to the corresponding signal an illumination of intensity corresponding to the intensity of the sound energy emanating from such'com- 16 ponent part of the object, thereby to produce a likeness of the object.

38. An electric system having, in combination, a plurality of piezoelectric sound-energy receiving elements for receiving sound waves from an object, a plurality of spaced electrodes respectively associated with each of the plurality of receiving elements, the electrode spacing providing sufiicient capacitance to produce resonance to the frequency of the received sound waves, means for scanning the receiving elements to develop signals, and means responsive to the signals and controlled synchronously with the scanning for producing a likeness of the object.

39. An electric system having, in combination, piezoelectric means of the type that produces electric energy when vibrated mechanicaly, means for converging sound energy emanating from an object upon the piezoelectric means to set the piezoelectric means into mechanical vibration thereby to produce electric energy, means for producing a biasing voltage to sensitize the piezoelectric means, and means controlled in accordance with the electric energy produced by the mechanical vibrations of the piezoelectric means for producing a likeness of the object.

40. An electric system having, in combination, mechanically vibratory sound-energy receiving means, means for converging sound energy emanating from an object upon the sound-energy receiving means to set the sound-energy receiving means into mechanical vibration thereby to produce electric energy, means for producing a biasing voltage to sensitize the sound-Wave receiving means, and means controlled in accordance with the electric energy produced by the mechanical vibrations of the sound-energy receiving means for producing a likeness of the object.

41. An electric system having, in combination, a bank of Rochelle-salt piezo-electric sound-receiving elements, means for focusing sound waves from an object upon the sound-receiving elements, a load circuit, means for permanently connecting the bank of receiving elements to the load circuit, means for scanning the receiving elements to develop signals in the load circuit representative of the sound-wave energy focused upon the receiving elements, and means operating in synchronism with the scanning means and responsive to the signals developed in the load circuit for producing a likeness of the object.

42. An electric system having, in combination, a bank of quartz piezo-electric sound-receiving elements, means for focusing sound waves from an object upon the sound-receiving elements, a load circuit, means for permanently connecting the bank of receiving elements to the load circuit, means for scanning the receiving elements to develop signals in the load circuit representative of the sound-wave energy focused upon the receiving elements, and means operating in synchronism with the scanning means and responsive to the signals developed in the load circuit for producing a likeness of the object;

43. An electric system having, in combination, a bank of di-hydrogen potassium phosphate piezo-electric sound-receiving elements, means for focusing sound waves from an object upon the sound-receiving elements, a load circuit, means for permanently connecting the bank of receiving elements to the load circuit, means for scanning the receiving elements to develop signals-in 17 the load circuit representative of the sound-wave energy focused upon the receiving elements, and means operating in synchronism with the scanning means and responsive to the signals developed in the load circuit for producing a likeness of the object.

ROBERT HARVEY RINES.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,895,442 Bowser -1 Jan. 31, 1933 1,972,491 Nicolson Sept. 4, 1934 Number Number Name Date Gray Feb. 25, 1936 Sokoloff June 27, 1939 Kellog Oct. 8, 1940 Mason Feb. 4, 1941 Polke Mar. 11, 1941 Woifi July 7, 1942 Hefele Apr. 10, 1945 Mecham Apr. 15, 1947 Dimmick Nov. 9, 1948 FOREIGN PATENTS Country Date Great Britain Feb. 12, 1931 Great Britain Dec. 19, 1941 France Apr. 9, 1941 Certificate of Correction Patent N 0. 2,528,725 November 7, 1950 ROBERT HARVEY RINES It is hereby certified that error appears in the printed specification of the above numbered patent requiring correction as follows:

Column 16, lines 16 and 17, strike out of the type that produces electric energy when vibrated mechanicaly; line 30, after the Word means first occurrence, and before the comma, insert of the type that produces electric energy when vibrated mechanically;

and that the said Letters Patent should be read as corrected above, so that the same may conform to the record of the case in the Patent Oflice Signed and Sealed this 23rd day of January, A. D. 1951.

THOMAS F. MURPHY,

Assistant Gammz'sse'oner of Patents.

Certificate of Correction Patent N 0. 2,528,725 November 7, 1950 ROBERT HARVEY RINES It is hereby certified that error appears in the printed specification of the above numbered patent requiring correction as follows:

Column 16, lines 16 and 17 strike out of the type that produces electric energy when vibrated mechanicaly; line 80, after the Word means first occurrence, and before the comma, insert of the type that produces electric energy when vibrated mechanically;

and that the said Letters Patent should be read as corrected above, so that the same may conform to the record of the case in the Patent Oflice. Signed and sealed this 23rd day of January, A. D. 1951.

THOMAS F. MURPHY,

Assistant Commissioner of Patents.