US2299260A - Energy translation utilizing pyroelectricity - Google Patents
Energy translation utilizing pyroelectricity Download PDFInfo
- Publication number
- US2299260A US2299260A US292902A US29290239A US2299260A US 2299260 A US2299260 A US 2299260A US 292902 A US292902 A US 292902A US 29290239 A US29290239 A US 29290239A US 2299260 A US2299260 A US 2299260A
- Authority
- US
- United States
- Prior art keywords
- pyroelectric
- heat
- energy
- tourmaline
- electrodes
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
- 238000013519 translation Methods 0.000 title description 6
- 230000005616 pyroelectricity Effects 0.000 title description 5
- 229940070527 tourmaline Drugs 0.000 description 17
- 229910052613 tourmaline Inorganic materials 0.000 description 17
- 239000011032 tourmaline Substances 0.000 description 17
- 238000000576 coating method Methods 0.000 description 11
- 239000013078 crystal Substances 0.000 description 10
- 239000000463 material Substances 0.000 description 8
- 238000010438 heat treatment Methods 0.000 description 7
- 239000011248 coating agent Substances 0.000 description 6
- 230000010287 polarization Effects 0.000 description 6
- 239000000126 substance Substances 0.000 description 6
- 230000008859 change Effects 0.000 description 4
- 239000004020 conductor Substances 0.000 description 4
- 239000002178 crystalline material Substances 0.000 description 4
- 230000005855 radiation Effects 0.000 description 4
- 238000012546 transfer Methods 0.000 description 4
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 description 3
- 229910052734 helium Inorganic materials 0.000 description 3
- 239000001307 helium Substances 0.000 description 3
- SWQJXJOGLNCZEY-UHFFFAOYSA-N helium atom Chemical compound [He] SWQJXJOGLNCZEY-UHFFFAOYSA-N 0.000 description 3
- 239000001257 hydrogen Substances 0.000 description 3
- 229910052739 hydrogen Inorganic materials 0.000 description 3
- 238000000034 method Methods 0.000 description 3
- 230000004048 modification Effects 0.000 description 3
- 238000012986 modification Methods 0.000 description 3
- 230000003287 optical effect Effects 0.000 description 3
- 230000000737 periodic effect Effects 0.000 description 3
- 239000011358 absorbing material Substances 0.000 description 2
- 229910052729 chemical element Inorganic materials 0.000 description 2
- 230000006835 compression Effects 0.000 description 2
- 238000007906 compression Methods 0.000 description 2
- 238000001816 cooling Methods 0.000 description 2
- 239000007789 gas Substances 0.000 description 2
- INHCSSUBVCNVSK-UHFFFAOYSA-L lithium sulfate Chemical compound [Li+].[Li+].[O-]S([O-])(=O)=O INHCSSUBVCNVSK-UHFFFAOYSA-L 0.000 description 2
- BASFCYQUMIYNBI-UHFFFAOYSA-N platinum Chemical compound [Pt] BASFCYQUMIYNBI-UHFFFAOYSA-N 0.000 description 2
- LJCNRYVRMXRIQR-OLXYHTOASA-L potassium sodium L-tartrate Chemical compound [Na+].[K+].[O-]C(=O)[C@H](O)[C@@H](O)C([O-])=O LJCNRYVRMXRIQR-OLXYHTOASA-L 0.000 description 2
- 230000004044 response Effects 0.000 description 2
- 230000035945 sensitivity Effects 0.000 description 2
- 235000011006 sodium potassium tartrate Nutrition 0.000 description 2
- DYKCZVHJLMDZEP-UHFFFAOYSA-N 2,3-dihydroxybutanedioic acid tetrahydrate Chemical compound O.O.O.O.OC(=O)C(O)C(O)C(O)=O DYKCZVHJLMDZEP-UHFFFAOYSA-N 0.000 description 1
- 238000010521 absorption reaction Methods 0.000 description 1
- 238000009825 accumulation Methods 0.000 description 1
- 230000009471 action Effects 0.000 description 1
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 1
- 229910052782 aluminium Inorganic materials 0.000 description 1
- 230000008901 benefit Effects 0.000 description 1
- 230000001419 dependent effect Effects 0.000 description 1
- 230000030808 detection of mechanical stimulus involved in sensory perception of sound Effects 0.000 description 1
- JXTNYTBZEWFKNR-UHFFFAOYSA-L dilithium;selenate Chemical compound [Li+].[Li+].[O-][Se]([O-])(=O)=O JXTNYTBZEWFKNR-UHFFFAOYSA-L 0.000 description 1
- 239000000428 dust Substances 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 239000002245 particle Substances 0.000 description 1
- 230000002093 peripheral effect Effects 0.000 description 1
- 229910052697 platinum Inorganic materials 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- 238000000926 separation method Methods 0.000 description 1
- 238000004804 winding Methods 0.000 description 1
Images
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01G—CAPACITORS; CAPACITORS, RECTIFIERS, DETECTORS, SWITCHING DEVICES, LIGHT-SENSITIVE OR TEMPERATURE-SENSITIVE DEVICES OF THE ELECTROLYTIC TYPE
- H01G7/00—Capacitors in which the capacitance is varied by non-mechanical means; Processes of their manufacture
- H01G7/02—Electrets, i.e. having a permanently-polarised dielectric
- H01G7/028—Electrets, i.e. having a permanently-polarised dielectric having a heterogeneous dielectric
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
- H04R23/00—Transducers other than those covered by groups H04R9/00 - H04R21/00
-
- H—ELECTRICITY
- H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
- H10N—ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
- H10N15/00—Thermoelectric devices without a junction of dissimilar materials; Thermomagnetic devices, e.g. using the Nernst-Ettingshausen effect
- H10N15/10—Thermoelectric devices using thermal change of the dielectric constant, e.g. working above and below the Curie point
Definitions
- This invention relates to methods of and apparatus for utilizing pyroelectricity in energy translation systems.
- pyroelectricity may be readily demonstarted by subjecting a crystal of tourmaline suspended by an electrically insulating thread to a heating atmosphere. One end of the crystal will be found to be positively electrified and the other negatively electrified. When .such a pyroelectric crystal is cooled its electrical polarity becomes reversed from that produced by heating; become negative and that which was negative has become positive. If the crystal be subjected to alternate heating and cooling an alternating electrical polarization will ensue.
- An object of this invention is to take advantage positive and negative charges.
- This 'phe-' 'nomenon known as pyroelectricity has been obthe end which was positive now has trically insulated from each other.
- a circuit leading from the electrodes of the pyroelectric plate may be connected to an amphfier with the output circuit of which an indicator is electrically assoclated. Consequently, incidence of the wave energy beam upon the pyroelectric plate may be made evident by the indicator.
- Sound waves in air may be allowed to fall directly upon the pyroelectric plate or may pass through a diaphragm to a confined atmosphere in which the pyroelectric plate is positioned.
- adiabatic compression and rarefaction of the atmosphere immediately surrounding the plate give rise to a fluctuation in its temperature which is partially communicated to the pyroelectric plate thus causing a corresponding fluctuationof its temperature and a consequent alternating elecof the pyroelectric phenomenon in order to translate into electrical energy, impulses or trains of heat waves or of any wave energy which are capable of producing temperature variations in pyroelectric material.
- Another object of the invention is to translate radiant energy into electrical energy by means. of pyroelectric apparatus which may at the same time be very rugged and extremely sensitive.
- An additional object of the invention is to improve the eifectiveness of a pyroelectric translatlng device for converting hert bearing waves into corresponding electrical waves.
- a further object of the invention is to provide a sensitive detector for radiation energy of electromagnetic character in the frequency ranges commonly designated as heat and, light.
- a plate of a pyroelectric material is suspended in a medium traversed by beams of wave energy which'on incidence upon the material cause its temperature to change.
- the resulting electrification of the plate gives rise to charges upon conducting electrodes or coatings nection with the accompanying drawings in I placed in close association with the plate but electrical polarization at the electrodes associated with the plate.
- the principle of the invention is applicable to any sort of systemijin which a disturbing or impelling force can set up an alternating temperature in a pyroelectric ele ment thus giving rise to a corresponding alternating pyroelectric charge between the associated electrodes.
- the pyroelectrid operation may be utilized to enable the system to serve as a photoelectric cell or radiation detector.
- Fig. 1 shows a circular disc of pyroelectric material
- Fig. 2 is another view of the disc of Fig. 1,
- Fig. 3 illustrates schematically a system for responding to sound waves and converting their energy by pyroelectric action to corresponding electrical waves
- Fig. 4 shows a modification in which the microphone element of Fig. 3 is positioned in an enclosed atmosphere of helium or hydrogen;
- Fig. 5 shows a pyroelectric element having coatings similar to the element of Figs. 1 and 2 and with an additional black absorbing coating on one of its faces for converting radiant energy into heat;
- Fig. 6 discloses a system responsive to radiant light or heat employing the detecting element of Fig. 5;
- Figs. 7 and 8 disclose systems employing a pyroelectric element in conjunction with a Helmholtz resonator to respond to incoming sound waves.
- a disc I of tourmaline is cut from the virgin crystalline material in such a manner as to have its major or parallel plane faces extending perpendicular to the optical or Z axis of the crystalline material.
- the disc is preferably made very thin as, for example, of the order of .0015 to .005 of an inch in thiclmess.
- its major faces are provided with coatings 2 and 3 of conducting material such as aluminum or platinum which may be applied according to the methods now well known in the piezoelectric technique.
- the system of Fig. 3 makes'use of the pyroelectric disc of Figs. 1 and 2 in a system for detection of sound waves.
- the element I is preferably supported by lead wires 4 and 5 soldered to its opposite electrodes within an electrically shielded or screened casing 6, the apertures of which are sufficiently large to enable sound waves to freely pass through the casing.
- the adiabatic compression and rarefaction of the' atmosphere within the casing 6 in consequence of translation of sound waves produces a'variation in its temperature and, also, therefore, in the temperature.
- the corresponding fluctuating electrical polarization developed upon the conducting electrodes 2 and 3 of the element l enables the device to act as a microphone or a detector of sound waves.
- the leads 4 and. 5 areconnected respectively to the inner and outer conductors of a coaxial conductor system 1 leading to the input terminals of an electron discharge device 8 within a shielded container 9.
- Various mechanical and electrical details of the apparatus are omitted to simplify the drawings. It will be readily understood, however, that the fluctuating potentials developed between the opposite electrodes oi the element I will be amplified by the device 0 and indicated by the responsive'device l0 in its output circuit.
- the electroresponsive device l0 may be a sensitive meter of any type or it may be -an electroacoustic device such as a telephone receiver or loud-speaker.
- Fig. 4 illustrates a system for translation of sound waves into electrical wave energy in which the pyroelectric element l is mounted in a hermetically sealed container I! provided with a flexible diaphragm member l3 capable of transferring sound wave pressures from the outer atmosphere to the atmosphere within the chamber.
- the pyroelectric element l. is electrically associated with a coaxial system I in the same manner as in thedisclosure of Fig. 3.
- the hermetically sealed chamber 12 not only protects the pyroelectric element from moisture and the accumulation oi dust particles but, also, enables the atmosphere immediately surrounding the element l to be made such that its density, speciilc heat and heat conductivity result in a greater temperature variation in the pyroelectric crystal for a given pressure amplitude in the atmosphere.
- the chamber preferably contains an atmosphere of hydrogen or helium to improve the heat transfer to the pyroelectric element.
- Fig. 5 discloses a modification of the pyroelectric device shown in Figs. 1 and 2 to adapt the device for reception of heat-bearing electromagnetic beams.
- a device similar to that of Fig. 2 is coated with a black absorbing coating ll of a type effective to convert incident beams of short electromagnetic waves into heat.
- any radiation which can be converted into heat by absorption such as electromagnetic waves of radiant heat or infra-red rays may be employed.
- Fig. 6 illustrates a system utilizing the device of Fig. 5 in which the pyroelectric element is enclosed in a sealed chamber I5 which may be exhausted to a very low pressure.
- the chamber ll is provided with a window l6 of a material transparent to the light or heat wave or other radiant energy beams. Accordingly, beams of radiant energy passing through the window and falling upon the coating ll of the pyroelectric element are converted into heat energy to vary the temperature of the pyroelectric element.
- the exhaustion of the chamber is carried to a highdegree for'the reason that the presence of air or other gas would, to an extent.
- a rotary interrupting device I1 is provided with vanes which traverse the path of the light beam thus momentarily intercepting the beam.
- the interrupter I1 is preferably driven by an electric motor i8 supplied with energy from alternating current mains IS.
- a variable controlling element 20 connected in the current supply circuit enables the speed of the motor II to be varied as desired or even to be changed in accordance with code impulses.
- FIGs. 7 and 8 Another instance of a purely pyroelectric apparatus is disclosed in Figs. 7 and 8 in which a Helmholtz resonator at, the natural rmonance frequency of which corresponds to the frequency of an incoming sound wave to be indicated or detected, is provided at its throat portion it with an element 24 of pyroelectric substance having electrodes 25 and 2% which are connected by the coaxial line 21 to the input of an amplifying or detecting device 28, the output circuit of which includes a current indicator 2! and the primary winding of a transformer 30 connected to a loudspeaker or other sound reproducer 35.
- a heating coil 32 in circuit with an external source 33 of heat electromotive force and a rheostat 36.
- Fig. 8 discloses a modification of the apparatus of Fig. 7 in which the pyroelectric crystal is surrounded by a heating coil 36. The transfer of heat from the coil 36 to the pyroelectric element M will accordingly be modulated by the alternating current air flow in the throat portion of the resonator.
- An apparatus for responding to electromagnetic wave energy of such wave-length as to convey heating energy comprising an evacuated container having a window pervious to radiant heat bearing waves, a thin element of pyroelectric material having electrodes upon which pyroelectric charges developed in the element may be impressed, means for supporting the element in front of the window and with its thinnest dimension extending in the direction of travel of the radiant waves, means for setting up intermittent variations in incoming radiant wave energy whereby the pyroelectric device is caused to yield a periodic electric response and means for varying the temperature of the pyroelectric element in consequence of the incidence of electromagnetic waves.
- a hermetically sealed chamber of electrically conducting material having a window transparent to heat-bearing rays, a pyroelectric element within the chamber having electrically separated conducting electrodes, means for supporting the pyroelectric element comprising two conducting leads integrally connected electrically to the respective electrodes, one lead being elsetrically connected to the chamber and the other insulated therefrom to enable pyroelectric E. M. F.s.
- the element to be applied to an external circuit connected between the insulated lead and the chamber, the supporting leads being so positioned as to cause the element to present a major surface to a beam of rays entering the window and incident upon the surface and a coating of heat-absorbing material on a portion of the surface of the element exposed to the rays whereby upon incidence of the rays a pyroelectric charge is impressed upon the elec-, trodes.
- a pyroelectric element comprising a flat plate of tourmaline having its'parallel flat faces perpendicular to the optical axis of the crystallinematerial, said plate having a thickness of the order of .0015 to .005 inch in order to increase its sensitivity to rapid variations of incident radiant energy, a source of radiant heat waves and means for supporting the tourmaline plate in a position to cause the incident radiant heat waves to fall upon one iv the parallel flat faces at substantially QO-degree angle of incidence.
- a system for receiving, detecting and indicating a beam of heat bearing rays comprising an extremely thin plate of tourmaline the thickness of which is parallel to the optical axis of the tourmaline material, means for supporting the tourmaline plate in a space substantially devoid of atmosphere whereby pyroelectric charges may develop upon. incidence of heat rays upon the tourmaline free from piezoelectric E. M. F35 occasioned by change in pneumatic pressure.
- the supporting means comprising a chamber impervious'to heat bearing rays except for a window whereby a beam may be intercepted and the tourmaline screened from random radiant energy from other directions, and means external to the window and in position in line with the window and the tourmaline plate to interrupt a beam of heat energy in a periodic manner to cause periodic pyroelectric charges to be produced at the faces of the tourmaline plate and means for indicating the condition of electrical charge stance having the property of delevoping electrical charges in response to changes in temperature and pneumatic pressure of the ambient at-- mosphere, conducting electrodes physically connected to the element and means adjacent the surface of the element and exposed to incoming radiant energy for causing at least a portion of the energy of a beam of heat-producing waves incident upon the element to be converted into to receive radiant energy and conducting electrode physically connected thereto to receive charges induced by change in the thermal condition of the material whereby the possible changes in pneumatic pressure to which the tourmaline is subject having been reduced to negligible degree the charges generated and impressed upon the electrodes are occasion
- An evacuated housing having a window transparent to heat-bearing rays
- pyroelectric element within the housing, said pyroelectric element comprising a plate of crystalline material .0015 to .005 inch thick, two electrodes respec-' tively adjacent to portions of the element between which pyroelectric charges are developed and a coating of energy absorbing material overlying the outer surface of one of the electrodes and means for supporting the element to present the face of the coated electrode to the transparent -window whereby heat-bearing rays are enabled to rapidly heat the element and the element may rapidly radiate heat energy to-malntain its sensitivity as a pyroelectric element.
Landscapes
- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Physics & Mathematics (AREA)
- Acoustics & Sound (AREA)
- Signal Processing (AREA)
- Microelectronics & Electronic Packaging (AREA)
- Radiation Pyrometers (AREA)
- Photometry And Measurement Of Optical Pulse Characteristics (AREA)
Priority Applications (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US292902A US2299260A (en) | 1939-08-31 | 1939-08-31 | Energy translation utilizing pyroelectricity |
FR867448D FR867448A (fr) | 1939-08-31 | 1940-10-10 | Dispositifs pyroélectriques |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US292902A US2299260A (en) | 1939-08-31 | 1939-08-31 | Energy translation utilizing pyroelectricity |
Publications (1)
Publication Number | Publication Date |
---|---|
US2299260A true US2299260A (en) | 1942-10-20 |
Family
ID=23126726
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US292902A Expired - Lifetime US2299260A (en) | 1939-08-31 | 1939-08-31 | Energy translation utilizing pyroelectricity |
Country Status (2)
Country | Link |
---|---|
US (1) | US2299260A (fr) |
FR (1) | FR867448A (fr) |
Cited By (13)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2509913A (en) * | 1944-12-14 | 1950-05-30 | Bell Telephone Labor Inc | Electric power source |
US2520602A (en) * | 1947-04-30 | 1950-08-29 | Rca Corp | Microwave mode changer and integrator |
US2520938A (en) * | 1944-10-07 | 1950-09-05 | Klein Elias | Tourmaline crystal transducer |
US2528726A (en) * | 1945-06-02 | 1950-11-07 | Rines Robert Harvey | Electric system |
US2643280A (en) * | 1942-10-26 | 1953-06-23 | Csf | Method and apparatus for power measurement and detection at ultrahigh frequencies |
US2711094A (en) * | 1949-06-25 | 1955-06-21 | Celanese Corp | Stop motion |
US2744197A (en) * | 1951-05-09 | 1956-05-01 | Globe Union Inc | Frequency stabilization |
US3149246A (en) * | 1958-10-10 | 1964-09-15 | Bell Telephone Labor Inc | Thermoelectric generators |
US3278769A (en) * | 1961-07-17 | 1966-10-11 | Howard M Graham | Method of temperature cycling ferroelectric ceramics through a temperature range below the curie point thereof |
US3459945A (en) * | 1966-11-07 | 1969-08-05 | Barnes Eng Co | Laser calorimeter with cavitated pyroelectric detector and heat sink |
US3508089A (en) * | 1967-03-31 | 1970-04-21 | Clifton C Cheshire | Apparatus for converting heat directly into electric energy |
US4317063A (en) * | 1978-10-28 | 1982-02-23 | Plessey Handel Und Investments Ag | Pyroelectric detectors |
US9180424B2 (en) * | 2010-09-11 | 2015-11-10 | Albert Chin-Tang Wey | Infrared assisted hydrogen generation |
Families Citing this family (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE1294704B (de) * | 1961-01-20 | 1969-05-08 | Electronique Appliquee | Anordnung zur temperaturabhaengigen Ausloesung von elektrischen Vorgaengen |
-
1939
- 1939-08-31 US US292902A patent/US2299260A/en not_active Expired - Lifetime
-
1940
- 1940-10-10 FR FR867448D patent/FR867448A/fr not_active Expired
Cited By (13)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2643280A (en) * | 1942-10-26 | 1953-06-23 | Csf | Method and apparatus for power measurement and detection at ultrahigh frequencies |
US2520938A (en) * | 1944-10-07 | 1950-09-05 | Klein Elias | Tourmaline crystal transducer |
US2509913A (en) * | 1944-12-14 | 1950-05-30 | Bell Telephone Labor Inc | Electric power source |
US2528726A (en) * | 1945-06-02 | 1950-11-07 | Rines Robert Harvey | Electric system |
US2520602A (en) * | 1947-04-30 | 1950-08-29 | Rca Corp | Microwave mode changer and integrator |
US2711094A (en) * | 1949-06-25 | 1955-06-21 | Celanese Corp | Stop motion |
US2744197A (en) * | 1951-05-09 | 1956-05-01 | Globe Union Inc | Frequency stabilization |
US3149246A (en) * | 1958-10-10 | 1964-09-15 | Bell Telephone Labor Inc | Thermoelectric generators |
US3278769A (en) * | 1961-07-17 | 1966-10-11 | Howard M Graham | Method of temperature cycling ferroelectric ceramics through a temperature range below the curie point thereof |
US3459945A (en) * | 1966-11-07 | 1969-08-05 | Barnes Eng Co | Laser calorimeter with cavitated pyroelectric detector and heat sink |
US3508089A (en) * | 1967-03-31 | 1970-04-21 | Clifton C Cheshire | Apparatus for converting heat directly into electric energy |
US4317063A (en) * | 1978-10-28 | 1982-02-23 | Plessey Handel Und Investments Ag | Pyroelectric detectors |
US9180424B2 (en) * | 2010-09-11 | 2015-11-10 | Albert Chin-Tang Wey | Infrared assisted hydrogen generation |
Also Published As
Publication number | Publication date |
---|---|
FR867448A (fr) | 1941-10-27 |
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