US2269115A - Cathode-ray tube - Google Patents

Cathode-ray tube Download PDF

Info

Publication number
US2269115A
US2269115A US365216A US36521640A US2269115A US 2269115 A US2269115 A US 2269115A US 365216 A US365216 A US 365216A US 36521640 A US36521640 A US 36521640A US 2269115 A US2269115 A US 2269115A
Authority
US
United States
Prior art keywords
tube
electrode
cathode
screen
ray
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
Application number
US365216A
Other languages
English (en)
Inventor
Stanley J Koch
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Allen B du Mont Laboratories Inc
Original Assignee
Allen B du Mont Laboratories Inc
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Priority to BE473665D priority Critical patent/BE473665A/xx
Application filed by Allen B du Mont Laboratories Inc filed Critical Allen B du Mont Laboratories Inc
Priority to US365216A priority patent/US2269115A/en
Application granted granted Critical
Publication of US2269115A publication Critical patent/US2269115A/en
Priority to GB975/42A priority patent/GB552622A/en
Priority to FR942455D priority patent/FR942455A/fr
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • 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
    • H01J29/82—Mounting, supporting, spacing, or insulating electron-optical or ion-optical arrangements

Definitions

  • My invention relates to improvements in cathode-ray tubes of the general type more particularly adapted for television reception, and such as is disclosed in Patent No. 2,186,635 issued Janu- Heretofore, the importance of electrode position, and size, shape and spacing of the same,
  • a objects of my invention to provide an improved point or potential range is finally reached, howconstruction of cathode-ray tube of the charever, whereat the sensitivity of deflection is reacter referred to in which the operating potenduced a prohibitive amount, so thatit is not tials, and dimensions in the tube structure itself, practical to further increase the brightness of the are such that a picture of the desired brightness picture by this method alone.
  • Another diificulty on the fluorescent screen can be obtained without has been found to reside in the matter of mainnecessarily or unduly interfering with the focus taining the scanning electron ray at a good focus or the sensitivity of deflection. on the fluorescent screen.
  • Another object of my invention resides in the certain changes or variations in some of the opprovision of an improved construction of cathodeerating potentials or in the structure of the tube ray tube of the character referred to, which has itself to correct for or improve upon certain opadvantages over those proposed heretofore in the crating conditions, the result has been to impair, 'way of a brighter or more intense picture on the at the same time, the operating action in other fluorescent screen for similar operating condiways, such as by causing some form of distortion tions, higher picture detail, greater uniformity of of the pattern or by causing some degree of dethe pattern, greater simplicity of construction focusing of the electron ray on the fluorescent and of assembly in manufacturing, and more screen.
  • Figure 1 is an enlarged, fragmentary view taken from Fig. 10, and being partly broken away, partly in elevation, and partly in section, the section being taken on the line ll in Fig. 2;
  • Fig. la is a detail, fragmentary view, partly in section and illustrative of a novel step in the assembly of my improved cathode-ray tube, in some cases;
  • Fig. 2 is a view looking toward the right in Fig. 1, the electron gun being shown in elevation and '66, 8-3 and -3 in Flam-1 and 2; and
  • Fig. 4a is an enlarged, fragmentary, sectional:
  • FIG. 10 is a longitudinal, sectional viewer a complete cathode-ray tube constructed and operating in accordance with my invention, the electron gun'and associated parts being shown 8 18-11" vation;
  • Fig. 11 is an enlarged view taken from and showing more clearly the electrodes comprisfing the electron gun.
  • my improved cathode-ray tube comprises a tube l0 having a bulbous portion II on the end wall of which is a fluorescent screen 9.
  • a fluorescent screen 9 In the neck portion l2 of the tube is the gun for developing the ray of electrons directed at and focused on the screen.
  • the gun is supported from the stem I5 which is sealed to the open end of the neck i2, and comprises a cathode IS, a modulating electrode 20 in which the cathode I6 is disposed, a first acceleratingelectrode 22, and a mica disc 24.
  • the gun comprises further a focusing electrade 29, 29a and a second accelerating electrode 30 provided with the apertured discs 30a and 30b.
  • Deflecting plates 33 are supported by the wires 3311/3312. 33c and 33d, and a second set of deflecting plates 36 is supported by the wires 36a,
  • the first or preaccelerating electrode 22 above the modulating electrode 20 is operated at the same voltage asthe second accelerating electrode 30.
  • a connection 42 is made from the electrode 30 to the electrode 20.
  • the outside diameter of the neck portion I 2 was made 2% inches
  • the distance between the edges 58a and 59b of the ring electrode" was made two inches
  • the distance between the edges 59a and "(1 was made 1 /2 inches
  • the distance between the edges 58d and 580 was made one inch.
  • a potential of say 10,000 volts can be applied to the top electrode 58, 5,000 volts to the electrode 30, and a picture intensity corresponding to 10,000 volts will be obtained accordingly, but instead of cutting down the deflection sensitivity byabout 50% as heretofore, it is only reduced by approximately 18% in my tube.
  • Y may be made equal to Z.
  • Z may be made from inch to 1 inches.
  • Electrode 58 +l0,000 volts
  • Electrode 59 +5000 volts
  • the ed e 58a of the electrode 58 may be disposed a distance of about an inch from the edge 9a of the screen 9.
  • the electrode 58 may be a coating of colloidal graphite known as Aquadag" and a terminal coating 58b of silver which contacts or overlaps the Aquadag coating at 580.
  • the electrode 59 is a silver coating.
  • a metal disc 3! provided with the circular openings shown in Figs. 3 and 4, and with a mica-disc insert 32.
  • acts as a conducting shield for 001- lecting stray electrons which otherwise would form or set up a halo on the screen 9 in the absence or presence of signal voltage. Such a halo, when signal is present, would reduce contrast.
  • the diameter of the shield 6! is relatively large, so that its edge is in close proximity to the wall of the neck of the tube.
  • a whisker 6 la spot-Welded to the shield and spring-biased outwardly to cause engagement of its free end with the electrode 59 provides connection between the latter and the shield.
  • the part 29a of the focusing electrode is secured to the ceramic rods by the straps 29b and 29c (Fig. 6).
  • the part 29 of the focusing electrode is secured to the ceramic rods by the straps 29d and 29e.
  • the electrode 22 is secured to theceramic rods by the straps 22a.
  • the electrode 20 is secured to the ceramic rods by the straps 20a, 20b and the complementary pieces 200.
  • the cathode I 6 is supported by a short piece of wire Ilia spot-welded to one of the straps l6b secured to the ceramic rods.
  • the cathode-heater is supported by having its terminals I6e spot-welded to the short pieces [5 of wire which are spot-welded to the respective terminal wires l6 and I6" extending through the press.
  • the wires 36b and 36d terminate at the mica disc 32, but the wire 36a continues to and terminates at the mica disc 24, and the wire 360 extends through disc 24 and is spot-welded to the terminal wire 36c extending through the press.
  • An important feature of my improved tube resides in the means for making connection to the intensifier electrode 58.
  • This comprises a coaxial cable made up of a wire 58f extending through a glass tube 589 which is bent as shown, and is provided with an outercoating 58h. of silver. As shown in Fig. 10, one end of the wire 58f makes contact with the silver coating 58!). The other end of the wire 58) is spot-welded to a short piece of wire 58k Fig. 8 which is spotwelded to one end of an L-shape piece 581'. The other end of the piece 587' is spot-welded to the terminal wire 58 which extends through the press.
  • the tube 589 extends loosely through the shield GI and the mica discs 32 and 24, and the silver coating 58h makes electrical contact with the shield 6
  • the bent glass tube 58g is placed in the position shown in Figs. .1 and 2, so that it clears.
  • the tube 589 is then rotated through degrees and moved axially so that its bifurcated end portion 581' straddles and interlocks with one leg of the L-shape piece 587, as shown in Fig. 1a and as indicated by dash-line in Fig. 8.
  • the tube 589 is in the position shown in Fig. 10 and the free end of the wire 58 engages the silver coating 58b.
  • connection 42 is spot-welded to the shield 6
  • One end of the wire 22b is spot-welded to the straps 22a, and the other end is spot-welded to the terminal wire 22' extending through the press.
  • Connection with the electrode 20 is made by a piece of. wire 20d spot-welded to the straps 20a and to the terminal wire 20 extending through the press.
  • Connection with the cathode I6 is made through a piece of wire l6c spot-welded to the straps I61) and to the terminal wire I6.
  • a connecting wire 29d is spot-Welded to the straps 29c and 29d.
  • the wire 29d passes through the disc 24 and is spot-welded to the terminal wire 29'.
  • connection to the intensifier electrode 58 is made by the terminal 58'.
  • Connection to electrode 59, shield BI, and electrodes 30 and 22 is made by the terminal wire 22'.
  • Connection to electrode 20 is made by the terminal wire 20'.
  • Connection to the cathode l6 and one side of the cathodeheater is made by the terminal wire i6, and connection to the other side of the cathode-heater is made by the terminal wire it".
  • Connection to electrode 29, 29a is made by the terminal wire 29'.
  • the ends of the supporting wires are sandwiched between the deflection plate and the strap 36c, and by reason of the stamped-out portions of the latter, the strap functions as a gauge for quickly and conveniently spacing and positioning the ends of the supporting wires properly and ensuring correct alignment of the parts and uniformity of construction.
  • the other deflection plates and the respective supporting wires therefor are secured together by similar straps, in the same way. Reenforcing pieces, such as 33', join the pairs of adjacent supporting wires for the deflecting plates.
  • the wire 36c passes through a grommet 32a having the portions 32c riveted over onto the mica disc 32, and the portions 32c spot-welded to the wire 360.
  • the distance from the grommet to the edge 32b provides suflicient insulation between the shield .6i and wire 360.
  • Similar grommets are used for the other wires which pass through or terminate at the mica discs 32 and 24.
  • a cathode-ray tube a tube having a screen at the end wall thereof, said tube at the end thereof opposite said screen being provided with a press, a gun supported by said press and disposed in said tube for developing a ray of electrons directed at and focused on said screen, deflecting means for said ray of electrons in said tube, an electrode extending along said tube and beyond said deflecting means in the direction toward said screen, a second electrode disposed between said first-named electrode and said screen for minimizing defocusing of the ray-spot on said screen and for minimizing reduction of deflection sensitivity, said second-named elect r ode being adapted to operate at a potential higher than the potential of operation of said first-named electrode, and connection means comprising a conductor extending through an elongated insulator having conducting material on the outside thereof, said conductor engaging said second-named electrode and extending along said tube within the same and through said press to provide exteriorly of said tube at said press a terminal for application of potential to said second
  • a cathode-ray tube a tube having a screen at the end wall thereof, a gun disposed in said tube for developing a ray of electrons directed at and focused on said screen, a press supporting said gun, means for deflecting said ray to cause the same to scan said screen.
  • an electrode extending along said tube and beyond said deflecting means in the direction toward said screen, a second electrode disposed between said screen and said first-named electrode, said second electrode being adapted to operate at a potential positive with respect to the potential of operation of said first-named electrode, the diameter of said tube at a plane in proximity to said screen being substantially greater than the maximum effective diameter of said screen, and connecting means comprising a conductor extending through an elongated insulator having conducting material on the outside thereof, said conductor extending from said second electrode and along said tube within the same and through said press to provide exteriorly of said tube at said press a terminal for application of potential to said second-named electrode.
  • a cathode-ray tube a tube provided with screen structure and with a gun for developing a ray of electrons directed at said screen structure, a pair of plates for deflecting said ray, at least one of said plates being supported by wires whose ends are disposed against one side of said plate at an edge thereof and are perpendicular to said edge, and a strap disposed against said ends and flush against said plate at said edge thereof and secured to said plat and said ends,
  • said strap being pressed out to receive and accommodate said ends whereby said strap initially can function as a gauge to space and position said ends with respect to said plate prior to the securing of said parts together.
  • a layer of conducting material on the inside of said tube between the gun and screen of said tube, means for supporting an electron gun in said tube, and an elongated insulator carrying an electrical conductor to contact with said layer of conducting material, said insulator and conductor being bent and revoluble with respect to said tube to provide contact of said conductor with said layer of insulating material.
  • a layer of conducting material on the inside of said tube between the gun and screen of said tube, means for supporting an electron gun in said tube. an electrical conductor to contact with said layer, an insulating supporting member for said conductor, and a conducting electrical shield on a portion of said member to prevent the electric field 0! said conductor from distorting the electron beam between the gun and the screen.
  • a layer of conducting material on the inside of said tube between the gun and screen of said tube means for sup- 10 porting an electron gun in said tube.
  • an electrical conductor to contact with said layer an insu-' lating supporting member for said conductor, and a conducting electrical shield on a portion of said member to prevent the electric field of said conductor from distorting theelectron beam between the gun and the screen, said member being bent and revoluble and means to locate and secure said member in its operating position.

Landscapes

  • Vessels, Lead-In Wires, Accessory Apparatuses For Cathode-Ray Tubes (AREA)
  • Cathode-Ray Tubes And Fluorescent Screens For Display (AREA)
US365216A 1940-11-12 1940-11-12 Cathode-ray tube Expired - Lifetime US2269115A (en)

Priority Applications (4)

Application Number Priority Date Filing Date Title
BE473665D BE473665A (fr) 1940-11-12
US365216A US2269115A (en) 1940-11-12 1940-11-12 Cathode-ray tube
GB975/42A GB552622A (en) 1940-11-12 1942-01-23 Improvements in cathode ray tubes
FR942455D FR942455A (fr) 1940-11-12 1946-04-03 Perfectionnements aux tubes à rayons cathodiques

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US365216A US2269115A (en) 1940-11-12 1940-11-12 Cathode-ray tube

Publications (1)

Publication Number Publication Date
US2269115A true US2269115A (en) 1942-01-06

Family

ID=23437953

Family Applications (1)

Application Number Title Priority Date Filing Date
US365216A Expired - Lifetime US2269115A (en) 1940-11-12 1940-11-12 Cathode-ray tube

Country Status (4)

Country Link
US (1) US2269115A (fr)
BE (1) BE473665A (fr)
FR (1) FR942455A (fr)
GB (1) GB552622A (fr)

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2432037A (en) * 1943-08-20 1947-12-02 Kreisler Mfg Corp Jacques Electron gun positioning means
US2483457A (en) * 1945-04-05 1949-10-04 Du Mont Allen B Lab Inc Cathode-ray tube
US2529134A (en) * 1947-10-02 1950-11-07 Rauland Corp Support for electron guns
US2545120A (en) * 1948-02-27 1951-03-13 Rca Corp Cathode-ray tube arc-over preventive
US2877370A (en) * 1955-08-25 1959-03-10 Rca Corp Electrode assembly
US3546525A (en) * 1969-01-21 1970-12-08 Sony Corp Electron gun electrical connection apparatus

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2432037A (en) * 1943-08-20 1947-12-02 Kreisler Mfg Corp Jacques Electron gun positioning means
US2483457A (en) * 1945-04-05 1949-10-04 Du Mont Allen B Lab Inc Cathode-ray tube
US2529134A (en) * 1947-10-02 1950-11-07 Rauland Corp Support for electron guns
US2545120A (en) * 1948-02-27 1951-03-13 Rca Corp Cathode-ray tube arc-over preventive
US2877370A (en) * 1955-08-25 1959-03-10 Rca Corp Electrode assembly
US3546525A (en) * 1969-01-21 1970-12-08 Sony Corp Electron gun electrical connection apparatus

Also Published As

Publication number Publication date
FR942455A (fr) 1949-02-09
GB552622A (en) 1943-04-16
BE473665A (fr)

Similar Documents

Publication Publication Date Title
GB1460120A (en) Electric circuit arrangements incorporating cathode ray tubes
US2170663A (en) Electron discharge device
US3008064A (en) Cathode-ray tube
US2269115A (en) Cathode-ray tube
US2139678A (en) Electron discharge device
US2852716A (en) Cathode ray tube and electron gun therefor
US3049641A (en) High transconductance cathode ray tube
US2185590A (en) Cathode ray tube
US3213311A (en) Electron discharge device
GB735632A (en) Improvements relating to cathode ray tubes and arrangements therefor
US3887837A (en) Cathode ray tube
GB1502876A (en) Cathode ray tube
US2176199A (en) Electron-discharge tube
US3027479A (en) Electron guns
US2228958A (en) Cathode ray tube
US4338543A (en) CRT With arc suppression means therein
US2596508A (en) Electron gun for cathode-ray tubes
US2592242A (en) Electron gun and mounting therefor
EP0018402A1 (fr) Canon electronique avec grille de commande portee au potentiel cathodique.
US5202606A (en) Cathode-ray tube with focussing structure and getter means
US2971108A (en) Electron discharge device
US3962599A (en) Shielding means for cathode ray tube
US4095138A (en) Electron gun having an arc-inhibiting electrode
JP2737616B2 (ja) 陰極線管及び陰極線管用の電界放出型陰極
US2137202A (en) Electron tube