Rca Inc.

Other

Sarnoff Corporation

Rca Licensing Corporation

David Sarnoff Research Center, Inc.

Rca Thomson Licensing Corp.

Roger Casanova Alig

David Arthur New

Dennis John Bechis

Barry Jay Thaler

George Herbert Needham Riddle

Attiganal Narayanaswamy Sreeram

Karl G Hernqvist

Stanley Bloom

Michael James Liberatore

William H Barkow

Aly Eid Fathy

Eric F Hockings

Leon J Vieland

Lubomyr S Onyshkevych

Josef Gross

Arthur J Ingle

An electron gun as for a cathode ray tube includes a plurality of electrodes biased at different potentials to electrostatically shape and focus the one or more electron beams produced thereby. A dynamic focus grid is driven by a substantial ac voltage signal at the horizontal line rate, which signal is undesirably coupled through parasitic capacitance to an intermediate grid located between the dynamic focus grid and the gun anode. A resistive biasing network includes a high value resistance to divide the anode potential to develop bias potential for the intermediate grid and a capacitance to ac couple the intermediate grid to ground potential. The resistance is formed in a single layer ceramic circuit and the capacitance is formed on the single layer ceramic circuit or on the tube neck. The ceramic circuit may be located in the tube neck on or with the electron gun.

Electron gun with resistor and capacitor

A cathode ray tube and a plural beam electron gun therefor include a main lens that comprises a tubular focus grid G and a conductive coating on the inner surface of the tube neck. The neck coating extends from the region of focus grid G towards the faceplate of the cathode ray tube. Preferably, the exit of the focus grid G is non-planar and is curved or undulated and focus grid G includes an aperture plate intermediate its entrance and exit. The aperture plate preferably has an elliptical center beam opening and connected-semi-elliptical outer-beam openings, to better converge and focus the outer and center electron beams. Also preferably, the focus grid G is centrally located in the tube neck and at least partly surrounded by the conductive neck coating.

Color picture tube including an electron gun in a coated tube neck

A projection tube has a phosphor-coated faceplate at one end of a vacuum envelope and a plural-beam providing electron lens structure at the opposite end thereof. The electron lens structure includes four electrodes having axially-aligned apertures defining parallel channels for the plural electron beams to pass through to be focused and converged onto a small spot on the faceplate. The first and second electrodes of the electron lens structure shape the electron beams and the third and fourth electrodes thereof converge and focus the electron beams toward the same location on the faceplate. The potential applied to the fourth electrode is at or close to the potential at the phosphor, and is substantially higher than the potential applied to the third electrode. The lens structures of the third and fourth electrodes may each include an inner electron lens structure and an outer electron lens structure. The lens structure of the invention provides a projection tube having greater brightness and/or smaller spot size than is conventionally available.

Dual beam projection tube and electron lens therefor

An ion source including an electron generating chamber and an ionization chamber adjacent the electron generating chamber and having an opening therebetween. The ionization chamber has a gas inlet opening and the electron generating chamber has a outlet. The gas inlet opening, the outlet and the opening between the two chambers are all on a common axis. The electron generating chamber has therein a cathode filament which extends completely around the axis and generates electrons, electrodes for directing the electrons transversely toward the axis and a deflection electrode for deflecting the electron flow along the axis and into the ionization chamber. An accelerator plate is adjacent the outlet and is adapted to attract ions generated in the ionization chamber along the axis and through the outlet.

Ion source

Apparatus, associated with a cathode ray tube (CRT), containing both a electrostatic focusing lens and a magnetic focusing lens for maintaining the focus of an electron beam within the CRT at any location on a CRT screen. The apparatus applies a dynamic focusing voltage to an electrostatic focus grid of an electron gun and applies a dynamic focusing current to a magnetic focus coil. The focusing voltage and current vary in accordance with the position of the electron beam on the screen. As such, the electron beam remains focused upon the screen for all beam positions.

Dynamic electrostatic and magnetic focusing apparatus for a cathode ray

A color picture tube includes a faceplate and a funnel attached to the faceplate. The faceplate has a horizontal dimension M.sub.h and a vertical dimension M.sub.v, with the dimensions having a ratio M.sub.h /M.sub.v greater than one. A magnetic shield is located within the tube. The magnetic shield has a front aperture in the proximity of the faceplate and a rear aperture remote from the faceplate. The front aperture has a horizontal dimension F.sub.h and a vertical dimension F.sub.v and the rear aperture has a horizontal dimension R.sub.h and a vertical dimension R.sub.v. The top and bottom of the rear aperature are close to the sides of the funnel and the sides of the rear aperture are spaced from the funnel by a spacing consistent with the entrance of the electron beams at maximum deflection into the shield.

Color picture tube having an internal magnetic shield

The present invention provides an improvement in color picture tubes. Such tubes include an electron gun for generating and directing three inline electron beams, a center beam and two side beams, along initially coplanar paths toward a screen of the tube. The gun includes a plurality of spaced electrodes which form a main focus lens for focusing the electron beams. The improvement comprises the plurality of spaced electrodes which form a main focus lens including three electrodes that form an einzel lens in the path of each electron beam. A first einzel lens electrode includes three inline cylinders through which the electron beams pass. A second einzel lens electrode includes a large oval cylinder that overlaps all three cylinders of the first einzel lens electrode. A third einzel lens electrode includes three inline cylinders which are overlapped by the oval cylinder. The oval cylinder includes means for shaping the main focus lens to focus the three electron beams stigmatically near ground potential and to converge the outer beams at the center of the screen.

Color picture tube having an inline electron gun with an einzel lens

The present invention provides an improvement in color picture tubes. Such tubes include an electron gun for generating and directing three inline electron beams, a center beam and two side beams, along initially coplanar paths toward a screen of the tube. The gun includes a plurality of spaced electrodes which form a main focus lens for focusing the electron beams. The improvement comprises the plurality of spaced electrodes which form a main focus lens including four electrodes that form an einzel lens in the path of each electron beam. A first einzel lens electrode includes a first portion having three inline apertures that are set back from a second portion having a single large aperture through which all three electron beams pass. A second einzel lens electrode includes a first portion having three inline apertures that are set back from a second portion having a single large aperture through which all three electron beams pass. The second portion of the first einzel lens electrode faces the second portion of the second einzel lens electrode. A third einzel lens electrode includes a first portion having three inline apertures that are set back from a second portion having a single large aperture through which all three electron beams pass. A fourth einzel lens electrode includes a first portion having three inline apertures set back from a second portion having a single large aperture through which all three electron beams pass. The second portion of the third einzel lens electrode faces the second portion of the fourth einzel lens electrode. The first portion of the second einzel lens electrode and the first portion of the third einzel lens electrode face each other and include means for forming a quadrupole lens in the path of each electron beam therebetween.

The present invention provides an improvement in a color picture tube having an inline electron gun for generating and directing three inline electron beams, comprising a center beam and two outer beams, along initially coplanar paths toward a screen of the tube. The beams pass through a deflection zone adapted to have two orthogonal magnetic deflection fields established therein. A first of the fields causes deflection of the beams in a first direction perpendicular to the inline direction of the beams, and a second of the fields causes deflection in a second direction parallel to the inline direction of the beams. The gun includes two shunts for shunting portions of both deflection fields around the outer beam paths. Each shunt comprises one magnetically permeable member having an aperture therein. Each shunt completely surrounds one of the electron beam paths. The improvement comprises each shunt being longer in the first direction than in the second direction and being symmetric about a central axis of the shunt that parallels the first direction and symmetric about another central axis of the shunt that parallels the second direction.

Color picture tube having inline electron gun with coma correction

A color display system includes a cathode-ray tube and yoke. The yoke is a non-converging type. The cathode-ray tube has en electron gun assembly for generating and directing three electron beams, located at the corners of an equilateral triangle, along paths toward a screen of the tube. The electron gun assembly comprises three electron guns each including electrodes that comprise a beam-forming region and electrodes that form a main focusing lens in the path of each electron beam. The main focusing lens is formed by at least two focusing electrodes. The focusing electrode closest to the beam-forming region includes a separated part adjacent to the paths of each of the electron beams. Each separated part forms a portion of the dipole lens structure in the path of an electron beam. Means are provided for applying dynamic signals to the separated parts which are related to the deflection of the electron beams. The dipole lens structures establish electrostatic dipole fields in the path of the three electron beams that cause the beams to converge at the screen for all angles of deflection.

Color display system with electrostatic convergence means

An improved color picture tube has an inline electron gun for generating and directing three electron beams, comprising a center beam and two outer beams, along coplanar paths toward a screen of the tube. The three beams pass through a deflection zone adapted to have vertical and horizontal magnetic deflection fields established therein. The improvement comprises the inclusion of means for nonlinearly increasing the effect of the vertical magnetic deflection field on the center beam relative to the outer beams with increasing angles of vertical deflection of the beams.

Color picture tube having improved electron gun

The present invention is an improvement in an electron gun for use in a cathode ray tube. Such gun includes at least one cathode and a plurality of electrodes spaced from the cathode. At least two of the electrodes form a main focusing lens and the electrode nearest the cathode which forms the main focusing lens includes extrusions about an aperture therein. The improvement comprises means located at the end of the gun opposite the cathode for blocking the exit from the gun of electrons emitted from the extrusions.

Electron gun with afterglow eliminator

An improved color picture tube has an inline electron gun for generating and directing three electron beams, a center beam and two side beams, along coplanar paths toward a screen of the tube. The gun includes a main focusing lens for focusing the electron beams. The main focusing lens is formed by two spaced electrodes, each having three separate inline apertures therein. Each electrode also includes a peripheral rim. The peripheral rims of the two electrodes face each other. The apertured portion of each electrode is within a recess set back from the rim. The recesses of the electrodes have substantially the same dimension perpendicular to the inline directions of the inline apertures as the dimension parallel to the inline direction of the inline apertures. However, the recesses have lesser dimensions along diagonals angled at approximately 45 degrees with respect to the inline direction of the inline apertures. The electrodes are connected by four support rods that are peripherally attached to the electrodes along the diagonals.

Color picture tube having an improved expanded focus lens type inline

An improved color picture tube has an inline electron gun for generating and directing three electron beams, a center beam and two side beams, along coplanar paths toward a screen of the tube. The gun includes prefocus lens electrodes and main focus lens electrodes for focusing the electron beams. The main focus lens is formed by two spaced electrode members. The improvement includes the combination of features related to these two electrode members. One of the electrodes forming the main focus lens is an internal conductive coating on the neck. The other electrode includes three parts. First, there is a cylindrical portion that is smaller in diameter than the neck and is located in overlapped relation with respect to the conductive internal coating. Second, an apertured portion of the electrode includes three inline apertures which are aligned with the electron beam paths. And third, means are located between the cylindrical and apertured portions for controlling the astigmatism of the focus of the two side beams.

Color picture tube having an improved inline electron gun

An improvement is made in a color picture tube having an inline electron gun for generating and directing a plurality of electron beams along coplanar paths toward a screen of the tube. The gun includes a main focus lens for focusing the electron beams which is formed by two spaced electrodes. Each electrode includes a portion having a plurality of apertures therein equal to the number of electron beams. Each electrode also includes a peripheral rim. The peripheral rims of the two electrodes face each other and the apertured portion of each electrode is within a recess set back from the rim. The improvement comprises the depths of the apertures in the electrodes being equal to the thickness of material of the electrodes. This aperture structure permits greater penetration of the electrostatic lines of the main focus lens into the electrodes behind the apertured portions of the electrodes. This penetration of electrostatic lines provides a converging field for off-axis electron beams.

Growing community of inventors

Princeton Junction, NJ, United States of America

Roger Casanova Alig