US3398319A - Energizing system for color purity apparatus - Google Patents

Energizing system for color purity apparatus Download PDF

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US3398319A
US3398319A US513693A US51369365A US3398319A US 3398319 A US3398319 A US 3398319A US 513693 A US513693 A US 513693A US 51369365 A US51369365 A US 51369365A US 3398319 A US3398319 A US 3398319A
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deflection
winding
yoke
vertical
horizontal
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US513693A
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Lemke Eugene
Neal W Hursh
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RCA Corp
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RCA Corp
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Priority to US513693A priority Critical patent/US3398319A/en
Priority to BE691056D priority patent/BE691056A/xx
Priority to GB5587066A priority patent/GB1174589A/en
Priority to NL6617501A priority patent/NL6617501A/xx
Priority to SE1709366A priority patent/SE337436B/xx
Priority to FR87392A priority patent/FR1505048A/en
Priority to ES0334512A priority patent/ES334512A1/en
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    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N9/00—Details of colour television systems
    • H04N9/12—Picture reproducers
    • H04N9/16—Picture reproducers using cathode ray tubes
    • H04N9/18—Picture reproducers using cathode ray tubes using separate electron beams for the primary colour signals
    • H04N9/20—Picture reproducers using cathode ray tubes using separate electron beams for the primary colour signals with more than one beam in a tube
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J29/00—Details of cathode-ray tubes or of electron-beam tubes of the types covered by group H01J31/00
    • H01J29/46—Arrangements of electrodes and associated parts for generating or controlling the ray or beam, e.g. electron-optical arrangement
    • H01J29/70—Arrangements for deflecting ray or beam
    • H01J29/701—Systems for correcting deviation or convergence of a plurality of beams by means of magnetic fields at least
    • H01J29/706—Deviation correction devices, i.e. having the same action on each beam
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J29/00—Details of cathode-ray tubes or of electron-beam tubes of the types covered by group H01J31/00
    • H01J29/46—Arrangements of electrodes and associated parts for generating or controlling the ray or beam, e.g. electron-optical arrangement
    • H01J29/70—Arrangements for deflecting ray or beam
    • H01J29/72—Arrangements for deflecting ray or beam along one straight line or along two perpendicular straight lines
    • H01J29/76—Deflecting by magnetic fields only
    • H01J29/764—Deflecting by magnetic fields only using toroidal windings

Definitions

  • An auxiliary yoke having horizontal and vertical coils is controlled by apparatus including a saturable reactor having an A.C. winding and a -D.C. winding.
  • the horizontal coils of the auxiliary yoke are coupled to the horizontal deflection Wave source through the A.C. reactor winding.
  • the current in the DC. winding is changed, causing the inductive reactance of the A.C.
  • the energization of the vertical coils of the auxiliary deflection yoke, and thereby the vertical deflection center is changed as a function of the vertical deflection angle and by the operation of magnetic contacts responsive to the current in the reactor D.C. winding.
  • This invention relates to cathode ray tube deflection systems and particularly to apparatus by which to control wide angle beam deflection in television picture tubes such as, for example, shadow mask type color picture tubes.
  • the beam deflection apparatus in such a cathode ray tube must effect not only the wide angle deflection of the beams to scan a raster at the luminescent screen, but also must function with a minimum of coma, astigmatism, degrouping and other undesired electron-optical effects.
  • Another problem encountered with wide angle beam deflection systems is that resulting from structural deformations occurring within the picture tube itself under varying temperature conditions.
  • the shadow mask in a color television picture tube may become distorted relative to the phosphor screen at elevated temperatures.
  • Such deflection center modification is particularly desirable in rectangular tubes because of the tendency of a rectangularly shaped shadow mask to become unsymmetrically distorted at elevated temperatures. Distortions of the character described, detract from color purity in such picture tubes.
  • a deflection system tor a cathode ray picture tube which includes a main deflection yoke which is energizable from suitable deflection wave sources to deflect one or more electron beams suitably to scan a substantially rectangular raster at a target electrode.
  • the system also includes an auxiliary deflection yoke which is operable suitably to modify the effective deflection center of the main yoke.
  • the control apparatus for operating the auxiliary yoke includes a variable reactor which has a main winding and a control winding.
  • the impedance of the main winding and thereby the energization of the auxiliary yoke at the horizontal beam deflection rate are changed by a change in the energization of the control winding.
  • the energizing circuit for the control winding includes an element (e.g., a thermistor) whose impedance changes in response to its environmental temperature.
  • the auxiliary yoke control apparatus also includes a temperature responsive switch (e.g.
  • the single figure of the drawing is a schematic circuit diagram of a portion of a television receiver embodying the color purity apparatus of the invention.
  • a shadow mask type of color television picture tube 1 is provided with a main deflection yoke 2 and an auxiliary deflection yoke 3.
  • the picture tube may be a 25 inch RCA type 25AP22 which has a substantially rectangular screen and is one in which the three electron beams are deflected by means including the yoke 2 through angles up to approximately It will be understood, however, that the invention may also be used with other types of picture tubes such as, for example, a 21 inch RCA type 21FBP22A which has a round screen and is one in which the electron beams are deflected through angles up to approximately 70.
  • the main deflection yoke 2 may be of the 90 variety such as disclosed in Patent 3,169,207 granted Feb. 9, 1965, to M.
  • the yoke 2 alternatively may be of the type disclosed in Patent 2,824,267 granted Feb. 18, 1958, to W. H. Barkow, when a picture tube of the 70 round variety is used. It is to be understood that the present invention is not limited to use with such tubes as those referred to, but also may be used with substantially equal facility with other types of tubes such as a 19 inch rectangular tube identified by RCA type 19EYP22.
  • the main deflection yoke 2 has a pair of horizontal deflection coils 4 and a pair of vertical deflection coils 5.
  • the auxiliary deflection yoke 3 also has a pair of horizontal deflection coils 6 and a pair of vertical deflection coils 7.
  • the auxiliary yoke may take any of the forms shown in the concurrently filed application of R. L. Barbin, Ser. No. 513,774 and titled Auxiliary Beam Deflection Yoke.
  • the auxiliary yoke may be mounted in front of the main deflection yoke 2 as shown in the drawing or alternatively behind the main yoke as desired.
  • the beam deflection circuit includes horizontal and vertical output tubes 8 and 9 which, it will be understood, are suitably driven in a conventional manner by substantially sawtooth voltage waves respectively at the line and field repetition rates.
  • the output circuit of the horizontal output tube is connected to a winding 11 of a horizontal output transformer 12.
  • the horizontal deflection coils 4 of the main deflection yoke 2 are connected to the transformer winding 11 in a conventional manner.
  • the vertical output tube 9 is connected to the primary winding 13 of a vertical output transformer 14, the secondary winding 15 of which is connected to the vertical deflection coils of the main deflection yoke 2 in series with the vertical deflection coils 7 of the auxiliary yoke 33.
  • the horizontal deflection coils 6 of the auxiliary yoke 3 are connected through a two-part or alternating current winding 16 of a saturable reactor 17 to an auxiliary winding 18 of the transformer 12.
  • the pulsating voltage produced in the winding 18 effects a substantially sawtooth current flow at the line repetition rate through the horizontal deflection coils 6 of the auxiliary yoke 3.
  • the amplitude of this sawtooth current depends on the inductive impedance of the alternating current winding 16 of the reactor 17.
  • the impedance of the winding 16 is variable as a function of the energization of a control or direct current winding 19 of the reactor 17.
  • the winding 19 is energized from a source of direct current such as represented by a battery 21 by means of a circuit which includes a thermistor 22.
  • the thermistor is mounted in a part of the chassis which experiences temperature variations comparable to and/or representative of the temperature changes to which the shadow mask and associated parts of the picture tube 1 are expo ed.
  • the thermistor may be mounted on the core of the horizontal output transformer 12.
  • the thermistor 22 has a negative temperature coefiicient whereby its resistance decreases with heat.
  • a reed switch 23 is mounted inside of the control winding 19 of the reactor 17.
  • the switch may be of the type described in an article titled Magnetic Reed Switches and Relays by Gary A. Lehmann, published in Electronics World of September 1965 at pages 23 to 26 and 64.
  • the switch 23 has two normally closed magnetic contacts 24 which are connected respectively to opposite ends of the vertical deflection coils 7 of the auxiliary yoke 3.
  • a switch with normally open contacts may also be used with a slightly modified auxiliary yoke of the type disclosed in the concurrently filed Barbin application.
  • the thermistor 22 is relatively cool and its resistance is sufficiently high that only a small current flows through the direct current winding 19 of the reactor 17.
  • the inductive impedance of the alternating winding 16 of the reactor 17 is relatively high so that the horizontal deflection coils 6 of the axuiliary yoke 3 are energized from the output transformer winding 18 only to a small degree.
  • the magnetic field produced by the described small current flow in the reactor winding 19 is insufficient to open the reed switch contacts 24.
  • the vertical deflection coils 7 of the auxiliary yoke 3 are energized by induction from the vertical deflection coils 5 of the main yoke 2.
  • the described operating control of the coils 6 and 7 of the auxiliary yoke 3, together with the usual energization of the coils 4 and 5 of the main yoke 2 produce a given effective deflection center for the electron beams.
  • the resistance of the thermistor 22 decreases permitting more current to flow through the direct current winding 19 of the reactor 17.
  • the inductive impedance of the alternating current winding 16 decreases and the energization of the horizontal deflection coils 6 of the auxiliary yoke 3 increases.
  • the effective electron beam deflection center is, thus, suitably modified to maintain the desired relationship between the electron beams and the shadow mask.
  • the described inductive energization of the vertical deflection coils 7 of the auxiliary yoke is not changed until a particular elevated temperature is reached. At such time the direct current energization of the reactor winding 19 is enough to produce a magnetic field of suflicient strength to open the reed switch contacts 24. This action effectively enables energization of the vertical deflection coils 7 of the auxiliary yoke 3 from the vertical deflection output transformer winding 15. Thus, there is produced a suitable modification of the effective vertical beam deflection center.
  • the apparatus shown and described constitutes a practical beam deflection system which operates to modify the effective deflection center of a cathode ray picture tube as functions of the angle of beam deflection and of the environmental temperature.
  • a deflection system for a cathode ray picture tube including a main deflection yoke having horizontal and vertical coils energiz-able respectively from horizontal and vertical deflection wave sources to deflect an electron beam horizontally and vertically to scan a substantially rectangular raster at a luminescent screen and also including an auxiliary deflection yoke having horizontal and vertical coils energiz-able to modify the effective deflection center of said main yoke, apparatus for energizing said auxiliary yoke comprising:
  • a saturable reactor having an alternating current winding and a direct current Winding
  • said alternating winding connecting the horizontal coils of said auxiliary yoke to said horizontal deflection wave source in a manner to control the energization of said horizontal auxiliary yoke coils and hence the modification of the effective horizontal deflection center as a function of the inductive impedance of said alternating current winding and as a function of the horizontal deflection angle of said beam;
  • means including a set of magnetic contacts at other temperatures operative in response to current in said direct current winding-to vary the energization of said vertical auxiliary yoke coils in a manner to modify the effective vertical deflection center in an opposite sense to said one sense as a function of the vertical deflection angle of said beam.
  • a deflection system for a cathode ray picture tube including a main deflection yoke having horizontal and vertical coils energizable respectively from horizontal and vertical deflection wave sources to deflect an electron beam horizontally and vertically .to scan a substantially rectangular raster at a luminescent screen and also including an auxiliary deflection yoke having horizontal and vertical coils energizable to modify the effective deflection center of said main yoke, apparatus for energizing said auxiliary yoke comprising:
  • a saturable reactor having an alternating current Winding and a direct current winding
  • means including a pair of magnetic contacts located adjacent to said direct current reactor Winding and operative at other temperatures in response to current in said direct current winding to vary the energization of said vertical auxiliary yoke coils in a manner to modify the effective vertical deflection center in an opposite sense to said one sense as a function of the vertical deflection angle of said beam.
  • a deflection system for a cathode ray picture tube including a main deflection yoke having horizontal and vertical coils energizable respectively from horizontal and vertical deflection wave sources to deflect an electron beam horizontally and vertically to scan a substantially rectang-ular raster at a luminescent screen and also including an auxiliary deflection yoke having horizontal and vertical coils energizable to modify the effective deflection center of said main yoke, apparatus for energizing said auxiliary yoke comprising:
  • a saturable reactor having an alternating current winding and a direct current winding
  • a deflection system for a cathode ray picture tube including a main deflection yoke having horizontal and vertical coils energizable respectively from horizontal and vertical deflection wave sources to deflect an electron beam horizontally and vertically to scan a substantially rectangular raster at a luminescent screen and also including an auxiliary deflection yoke having horizontal and vertical coils energiza-ble to modify the effective deflection center of said main yoke, apparatus for energizing said auxiliary yoke comprising:
  • variable reactor having a main winding and a control winding
  • the inductive impedance of said main winding being inversely proportional to the energization of said control winding
  • means including a resistor having a negative temperature coefficient connecting said reactor control winding to a source of direct current energy to vary the direct current in said control winding in direct proportion to temperature changes;
  • means including said relay contacts to effectively connect the respective vertical coils of said main and auxiliary yokes in series to said vertical deflection wave source, whereby to modify the effective vertical deflection center of said main yoke under elevated temperature conditions in a second sense opposite to said first sense as a function of the vertical deflection angle of said beam.

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Description

Aug. 20, 1968 LEMKE ET AL 3,398,319
ENERGIZING SYSTEM FOR COLOR PURITY APPARATUS Filed Dec. 14, 1965 INVENTOR. A E/65v! ZFMKE M! M war/I 3 United States Patent 3,398,319 ENERGIZING SYSTEM FOR COLOR PURITY APPARATUS Eugene Lemke and Neal W. Hursh, Indianapolis, Ind.,
assignors to Radio Corporation of America, a corporation of Delaware Filed Dec. 14, 1965, Ser. No. 513,693 4 Claims. (Cl. 315-27) ABSTRACT OF THE DISCLOSURE An auxiliary yoke having horizontal and vertical coils is controlled by apparatus including a saturable reactor having an A.C. winding and a -D.C. winding. The horizontal coils of the auxiliary yoke are coupled to the horizontal deflection Wave source through the A.C. reactor winding. As the temperature changes, the current in the DC. winding is changed, causing the inductive reactance of the A.C. winding to change, thereby affecting the energization of the horizontal auxiliary deflection coils and the effective horizontal deflection center as a function of the temperature change and the horizontal deflection angle. The energization of the vertical coils of the auxiliary deflection yoke, and thereby the vertical deflection center, is changed as a function of the vertical deflection angle and by the operation of magnetic contacts responsive to the current in the reactor D.C. winding.
This invention relates to cathode ray tube deflection systems and particularly to apparatus by which to control wide angle beam deflection in television picture tubes such as, for example, shadow mask type color picture tubes.
In order to achieve wide angle beam deflection with good color purity in shadow mask color television picture tubes, it is necessary not only to maintain accurate coincidence of the eflective horizontal and vertical deflection centers but also to insure that the effective deflection centers are proper under all conditions to direct the electron beams through the appropriate apertures in the shadow mask to strike the desired phosphor elements. The beam deflection apparatus in such a cathode ray tube must effect not only the wide angle deflection of the beams to scan a raster at the luminescent screen, but also must function with a minimum of coma, astigmatism, degrouping and other undesired electron-optical effects. When the deflection angle becomes relatively great, such as 90 or more, it is difficult to design a single yoke by which to achieve all of the desired results. These problems become more severe when the neck of the cathode ray tube is decreased in. diameter, which is in conformity with present trends, because one or more of the beams tends to strike the neck of the tube and, consequently, will not reach the luminescent screen.
Another problem encountered with wide angle beam deflection systems is that resulting from structural deformations occurring within the picture tube itself under varying temperature conditions. For example, the shadow mask in a color television picture tube may become distorted relative to the phosphor screen at elevated temperatures. It is desirable that some modification of one or both of the eflFective beam deflection centers be made as some function of the temperatures within the tube. Such deflection center modification is particularly desirable in rectangular tubes because of the tendency of a rectangularly shaped shadow mask to become unsymmetrically distorted at elevated temperatures. Distortions of the character described, detract from color purity in such picture tubes.
It, therefore, is an object of the present invention to provide a beam deflection system by which to modify the ice eflective horizontal and/or vertical deflection centers of a cathode ray picture tube as functions of both the angle of beam deflection and of the environmental temperature.
In accordance with this invention, there is provided a deflection system tor a cathode ray picture tube which includes a main deflection yoke which is energizable from suitable deflection wave sources to deflect one or more electron beams suitably to scan a substantially rectangular raster at a target electrode. The system also includes an auxiliary deflection yoke which is operable suitably to modify the effective deflection center of the main yoke. The control apparatus for operating the auxiliary yoke includes a variable reactor which has a main winding and a control winding. The impedance of the main winding and thereby the energization of the auxiliary yoke at the horizontal beam deflection rate are changed by a change in the energization of the control winding. The energizing circuit for the control winding includes an element (e.g., a thermistor) whose impedance changes in response to its environmental temperature. The auxiliary yoke control apparatus also includes a temperature responsive switch (e.g. of the magnetic tape) having contacts which, under certain temperature conditions, enables energization of the auxiliary yoke at the vertical beam deflection rate by current derived directly from the vertical deflection wave source and, under other temperature conditions, elfectively energizes the auxiliary yoke at the vertical deflection rate by current induced from the main deflection yoke.
For a better understanding of the invention, reference now is made to the following description which is taken in conjunction with the accompanying drawing.
The single figure of the drawing is a schematic circuit diagram of a portion of a television receiver embodying the color purity apparatus of the invention.
In the drawing, a shadow mask type of color television picture tube 1 is provided with a main deflection yoke 2 and an auxiliary deflection yoke 3. The picture tube may be a 25 inch RCA type 25AP22 which has a substantially rectangular screen and is one in which the three electron beams are deflected by means including the yoke 2 through angles up to approximately It will be understood, however, that the invention may also be used with other types of picture tubes such as, for example, a 21 inch RCA type 21FBP22A which has a round screen and is one in which the electron beams are deflected through angles up to approximately 70. The main deflection yoke 2 may be of the 90 variety such as disclosed in Patent 3,169,207 granted Feb. 9, 1965, to M. J. Obert and R. L. Barbin, when a picture tube of the 25 inch rectangular variety is used. The yoke 2 alternatively may be of the type disclosed in Patent 2,824,267 granted Feb. 18, 1958, to W. H. Barkow, when a picture tube of the 70 round variety is used. It is to be understood that the present invention is not limited to use with such tubes as those referred to, but also may be used with substantially equal facility with other types of tubes such as a 19 inch rectangular tube identified by RCA type 19EYP22. The main deflection yoke 2 has a pair of horizontal deflection coils 4 and a pair of vertical deflection coils 5.
The auxiliary deflection yoke 3 also has a pair of horizontal deflection coils 6 and a pair of vertical deflection coils 7. The auxiliary yoke may take any of the forms shown in the concurrently filed application of R. L. Barbin, Ser. No. 513,774 and titled Auxiliary Beam Deflection Yoke. The auxiliary yoke may be mounted in front of the main deflection yoke 2 as shown in the drawing or alternatively behind the main yoke as desired.
The beam deflection circuit includes horizontal and vertical output tubes 8 and 9 which, it will be understood, are suitably driven in a conventional manner by substantially sawtooth voltage waves respectively at the line and field repetition rates. The output circuit of the horizontal output tube is connected to a winding 11 of a horizontal output transformer 12. The horizontal deflection coils 4 of the main deflection yoke 2 are connected to the transformer winding 11 in a conventional manner.
The vertical output tube 9 is connected to the primary winding 13 of a vertical output transformer 14, the secondary winding 15 of which is connected to the vertical deflection coils of the main deflection yoke 2 in series with the vertical deflection coils 7 of the auxiliary yoke 33.
The horizontal deflection coils 6 of the auxiliary yoke 3 are connected through a two-part or alternating current winding 16 of a saturable reactor 17 to an auxiliary winding 18 of the transformer 12. The pulsating voltage produced in the winding 18 effects a substantially sawtooth current flow at the line repetition rate through the horizontal deflection coils 6 of the auxiliary yoke 3. The amplitude of this sawtooth current depends on the inductive impedance of the alternating current winding 16 of the reactor 17. The impedance of the winding 16 is variable as a function of the energization of a control or direct current winding 19 of the reactor 17. The winding 19 is energized from a source of direct current such as represented by a battery 21 by means of a circuit which includes a thermistor 22. The thermistor is mounted in a part of the chassis which experiences temperature variations comparable to and/or representative of the temperature changes to which the shadow mask and associated parts of the picture tube 1 are expo ed. As an example, the thermistor may be mounted on the core of the horizontal output transformer 12. Although not necessarily limited thereto, the thermistor 22 has a negative temperature coefiicient whereby its resistance decreases with heat.
A reed switch 23 is mounted inside of the control winding 19 of the reactor 17. The switch may be of the type described in an article titled Magnetic Reed Switches and Relays by Gary A. Lehmann, published in Electronics World of September 1965 at pages 23 to 26 and 64. The switch 23 has two normally closed magnetic contacts 24 which are connected respectively to opposite ends of the vertical deflection coils 7 of the auxiliary yoke 3. A switch with normally open contacts may also be used with a slightly modified auxiliary yoke of the type disclosed in the concurrently filed Barbin application.
In the operation of the apparatus embodying the invention, when the television receiver is first turned on, the thermistor 22 is relatively cool and its resistance is sufficiently high that only a small current flows through the direct current winding 19 of the reactor 17. As a result, the inductive impedance of the alternating winding 16 of the reactor 17 is relatively high so that the horizontal deflection coils 6 of the axuiliary yoke 3 are energized from the output transformer winding 18 only to a small degree. The magnetic field produced by the described small current flow in the reactor winding 19 is insufficient to open the reed switch contacts 24. Hence, the vertical deflection coils 7 of the auxiliary yoke 3 are energized by induction from the vertical deflection coils 5 of the main yoke 2. Thus, at normal temperatures the described operating control of the coils 6 and 7 of the auxiliary yoke 3, together with the usual energization of the coils 4 and 5 of the main yoke 2, produce a given effective deflection center for the electron beams.
As the temperature increases, the resistance of the thermistor 22 decreases permitting more current to flow through the direct current winding 19 of the reactor 17. As a result, the inductive impedance of the alternating current winding 16 decreases and the energization of the horizontal deflection coils 6 of the auxiliary yoke 3 increases. The effective electron beam deflection center is, thus, suitably modified to maintain the desired relationship between the electron beams and the shadow mask.
The described inductive energization of the vertical deflection coils 7 of the auxiliary yoke is not changed until a particular elevated temperature is reached. At such time the direct current energization of the reactor winding 19 is enough to produce a magnetic field of suflicient strength to open the reed switch contacts 24. This action effectively enables energization of the vertical deflection coils 7 of the auxiliary yoke 3 from the vertical deflection output transformer winding 15. Thus, there is produced a suitable modification of the effective vertical beam deflection center.
It will be noted that the modification of the effective beam deflection centers is gradual and continuous horizontally and sharp and abrupt vertically. This has been found to be quite satisfactory because the modification of the effective vertical deflection center is less critical than that of the horizontal deflection center owing to the smaller vertical deflection angle.
The apparatus shown and described constitutes a practical beam deflection system which operates to modify the effective deflection center of a cathode ray picture tube as functions of the angle of beam deflection and of the environmental temperature.
What is claimed is:
1. In a deflection system for a cathode ray picture tube and including a main deflection yoke having horizontal and vertical coils energiz-able respectively from horizontal and vertical deflection wave sources to deflect an electron beam horizontally and vertically to scan a substantially rectangular raster at a luminescent screen and also including an auxiliary deflection yoke having horizontal and vertical coils energiz-able to modify the effective deflection center of said main yoke, apparatus for energizing said auxiliary yoke comprising:
a saturable reactor having an alternating current winding and a direct current Winding;
means including said alternating winding connecting the horizontal coils of said auxiliary yoke to said horizontal deflection wave source in a manner to control the energization of said horizontal auxiliary yoke coils and hence the modification of the effective horizontal deflection center as a function of the inductive impedance of said alternating current winding and as a function of the horizontal deflection angle of said beam;
means to vary the energization of said direct current reactor winding and hence the inductive impedance of said alternating curent reactor winding as a function of temperature;
means operative at certain temperatures to vary the energization of said vertical auxiliary yoke coil in a manner to modify the effective vertical deflection center in one sense as a function of the vertical deflection angle of said beam; and
means including a set of magnetic contacts at other temperatures operative in response to current in said direct current winding-to vary the energization of said vertical auxiliary yoke coils in a manner to modify the effective vertical deflection center in an opposite sense to said one sense as a function of the vertical deflection angle of said beam.
2. In a deflection system for a cathode ray picture tube and including a main deflection yoke having horizontal and vertical coils energizable respectively from horizontal and vertical deflection wave sources to deflect an electron beam horizontally and vertically .to scan a substantially rectangular raster at a luminescent screen and also including an auxiliary deflection yoke having horizontal and vertical coils energizable to modify the effective deflection center of said main yoke, apparatus for energizing said auxiliary yoke comprising:
a saturable reactor having an alternating current Winding and a direct current winding;
means connecting said alternating current winding in circuit with the horizontal coils of said auxiliary yoke and said horizontal deflection wave source in a manner to control the energization of said horizontal auxiliary yoke coils and hence the modification of the effective horizontal deflection center as a function of the inductive impedance of said alternating current winding and as a function of the horizontal deflection angle of said beam;
means responsive to temperature changes and connected in circuit with said direct current reactor winding and a source of direct current in a manner to vary the energization of said direct current winding and hence the inductive impedance of said alternating current reactor winding as a function of temperature;
means operative at first temperatures connecting the vertical coils of said auxiliary yoke to said vertical deflection :wave source, whereby to vary the energization of said vertical auxiliary yoke coils in a manner to modify the effective vertical deflection center in one sense as a function of the vertical deflection angle of said beam; and
means including a pair of magnetic contacts located adjacent to said direct current reactor Winding and operative at other temperatures in response to current in said direct current winding to vary the energization of said vertical auxiliary yoke coils in a manner to modify the effective vertical deflection center in an opposite sense to said one sense as a function of the vertical deflection angle of said beam.
3. In a deflection system for a cathode ray picture tube and including a main deflection yoke having horizontal and vertical coils energizable respectively from horizontal and vertical deflection wave sources to deflect an electron beam horizontally and vertically to scan a substantially rectang-ular raster at a luminescent screen and also including an auxiliary deflection yoke having horizontal and vertical coils energizable to modify the effective deflection center of said main yoke, apparatus for energizing said auxiliary yoke comprising:
a saturable reactor having an alternating current winding and a direct current winding;
means connecting said alternating current winding in series between the horizontal coils of said auxiliary yoke and said horizontal deflection wave source, whereby to control the energization of said horizontal auxiliary yoke coils and hence the modification of the effective horizontal deflection center as a function of the inductive impedance of said alternating current winding and as a function of the horizontal deflection angle of said beam;
means responsible to temperature changes and connected in series between said direct current reactor winding and a source of direct current to vary the energization of said direct current reactor winding and hence the inductive impedance of said alternating current reactor winding as a function of temperature;
means operative at elevated temperatures connecting the vertical coils of said auxiliary yoke in series between the vertical coils of said main yoke and said vertical deflection wave source, whereby to vary the energization of said vertical auxiliary yoke coils in a manner to modify the effective vertical deflection center in a first sense as a function of the vertical deflection angle of said beam; and
means including a pair of magnetic contacts located within said direct current reactor winding and operative in response to current in said direct current winding to effectively short circuit said vertical auxiliary yoke coi-ls at normal temperatures, whereby to vary the energization of said vertical auxiliary yoke coils in a manner to modify the effective vertical deflection center in a second sense opposite to said first sense as a function of the vertical deflection angle of said beam.
4. In a deflection system for a cathode ray picture tube and including a main deflection yoke having horizontal and vertical coils energizable respectively from horizontal and vertical deflection wave sources to deflect an electron beam horizontally and vertically to scan a substantially rectangular raster at a luminescent screen and also including an auxiliary deflection yoke having horizontal and vertical coils energiza-ble to modify the effective deflection center of said main yoke, apparatus for energizing said auxiliary yoke comprising:
a variable reactor having a main winding and a control winding;
the inductive impedance of said main winding being inversely proportional to the energization of said control winding;
means including a resistor having a negative temperature coefficient connecting said reactor control winding to a source of direct current energy to vary the direct current in said control winding in direct proportion to temperature changes;
means connecting said reactor main winding between the horizontal coils of said auxiliary yoke and said horizontal deflection wave source, whereby to modify the effective horizontal deflection center of said main yoke as functions of temperature and of the horizontal deflection angle of said beam;
means including contacts of a magnetic reed relay mounted within said reactor control winding to short circuit the vertical coils of said auxiliary yoke thus enabling inductive energization of said vertical auxiliary yoke coils from said main yoke under normal temperature conditions, whereby to modify the effective vertical deflection center in a first sense as a function of the vertical beam deflection angle; and
means including said relay contacts to effectively connect the respective vertical coils of said main and auxiliary yokes in series to said vertical deflection wave source, whereby to modify the effective vertical deflection center of said main yoke under elevated temperature conditions in a second sense opposite to said first sense as a function of the vertical deflection angle of said beam.
References Cited UNITED STATES PATENTS 2,834,901 5/1958 Barkow et a1 3l5--27 X 2,900,564 8/ 1959 Barkow. 3,329,859 7/ 1967 Lem'ke 315-27 X RODNEY D. BENNETT, Primary Examiner.
J. G. BAXT ER, Assistant Examiner.
US513693A 1965-12-14 1965-12-14 Energizing system for color purity apparatus Expired - Lifetime US3398319A (en)

Priority Applications (7)

Application Number Priority Date Filing Date Title
US513693A US3398319A (en) 1965-12-14 1965-12-14 Energizing system for color purity apparatus
BE691056D BE691056A (en) 1965-12-14 1966-12-12
GB5587066A GB1174589A (en) 1965-12-14 1966-12-13 Cathode Ray Tube apparatus including ab Auxiliary Beam Deflection YOke
NL6617501A NL6617501A (en) 1965-12-14 1966-12-13
SE1709366A SE337436B (en) 1965-12-14 1966-12-13
FR87392A FR1505048A (en) 1965-12-14 1966-12-14 Deflection system for cathode ray tubes
ES0334512A ES334512A1 (en) 1965-12-14 1966-12-14 An auxiliary yoke deviation device for makes in television image pipes. (Machine-translation by Google Translate, not legally binding)

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US513693A US3398319A (en) 1965-12-14 1965-12-14 Energizing system for color purity apparatus

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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3950671A (en) * 1973-03-19 1976-04-13 Sony Corporation Beam mislanding correcting system for color cathode ray tube
US5138238A (en) * 1991-05-17 1992-08-11 Thomson Consumer Electronics, Inc. Arrangement for correcting beam landing location error in a video display

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2834901A (en) * 1954-05-06 1958-05-13 Rca Corp Cathode ray tube adjunct
US2900564A (en) * 1956-08-31 1959-08-18 Rca Corp Temperature compensated electromagnetic deflection yoke
US3329859A (en) * 1964-08-31 1967-07-04 Rca Corp Pincushion correction circuit having saturable reactor and means for adjusting the phase and magnitude of the horizontal component

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2834901A (en) * 1954-05-06 1958-05-13 Rca Corp Cathode ray tube adjunct
US2900564A (en) * 1956-08-31 1959-08-18 Rca Corp Temperature compensated electromagnetic deflection yoke
US3329859A (en) * 1964-08-31 1967-07-04 Rca Corp Pincushion correction circuit having saturable reactor and means for adjusting the phase and magnitude of the horizontal component

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3950671A (en) * 1973-03-19 1976-04-13 Sony Corporation Beam mislanding correcting system for color cathode ray tube
US5138238A (en) * 1991-05-17 1992-08-11 Thomson Consumer Electronics, Inc. Arrangement for correcting beam landing location error in a video display

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