US2419177A - Cathode-ray tube coating - Google Patents
Cathode-ray tube coating Download PDFInfo
- Publication number
- US2419177A US2419177A US567343A US56734344A US2419177A US 2419177 A US2419177 A US 2419177A US 567343 A US567343 A US 567343A US 56734344 A US56734344 A US 56734344A US 2419177 A US2419177 A US 2419177A
- Authority
- US
- United States
- Prior art keywords
- cathode
- light
- ray tube
- tube
- coating
- 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
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
- H01J29/02—Electrodes; Screens; Mounting, supporting, spacing or insulating thereof
- H01J29/10—Screens on or from which an image or pattern is formed, picked up, converted or stored
- H01J29/18—Luminescent screens
- H01J29/24—Supports for luminescent material
Definitions
- This invention relates to external coatings for cathode-ray tubes which improve the contrast of the trace of the beam on the face of the tube so that the apparent brightness is increased even in the presence of strong ambient or surrounding light.
- a coating I of light-transmitting material is applied to the outside surface of the large end of a, cathode-ray tube 2.
- the color of this coating I corresponds to the color emitted by the fluorescent or phos phorescent coating 3 on the inside of the tube 2.
- This coating I adheres tenaciously to the outer face of glass tube 2 and will not be damaged by moisture, oil or grease.
- such outside coating is made strong and tough enough to withstand abrasion effects which might be encountered during handling or use of the tubes upon the faces of which these coatings are applied.
- Inert material in finely powdered form such as a divalent or trivalent metallic soap of the known sorts, is embodied in the coating I in amount sufficient to permit the desired degree of light transmission, while at the same time a suitable amount of specular diffusion of the transmitted light is caused to take place due to the presence of such 2 Claims.
- a luminescent screen 3 of zinc orthosilicate is applied to the inner face of the large end of the cathode-ray tube 2 and the outer face of this tube is coated with inert material I described above. This material is tinted to a shade of green so that it passes light between 4750 angstroms and 5600 angstroms.
- Such a film or layer transmits about lutions of natural or synthetic resin or combinaresponding as closely as possible to those of the fluorescent or phosphorescent luminosity of the screen material that is used.
- Such coatings I are particularly useful when applied to fluorescent screened tubes that are used in television as receiving tubes.
- the coating is tinted in accordance with the fluorescent luminosity of the screen material 3 that is used in such tubes.
- a zinc sulphide-zine cadmium sulphide screen material 3 is used a preponderately white luminescence is produced so that a neutral gray tint is uite suitable for the coatin I that is used on the face of the tube 2 and has been found to be very effective since it has a practically uniform transmission characteristic over the entire range of the visible spectrum.
- the light transmission through the coating material I has been found to be over of the fluorescent luminosity that is produced by bombarding the fluorescent screens of such tubes with cathode-rays or beams.
- Th loss of light is not noticeable in the darkness, while the increase in contrast produces a considerable increase of apparent brightness when the pattern or trace on the fluorescent screen 3 is observed even in the presence of strong ambient light. Glare is also eliminated to a large extent or practically entirely and no apparent increase in the size of the light spot caused by the beam is noticeable.
- the pattern or picture on the face of the tube can be observed in the usual way.
- cathode-ray tubes can be used without employing shields to exclude ambient light from the faces of the tubes even in surroundings where there is high ambient light.
- a cathode-ray tube having a screen and 3 having a layer or light-transmitting material on its face colored to correspond to the light produced by the cathode-ray beam of said tube on the screen thereof, said light-transmitting material having particles of inert material capable 5 of specular difl'ractlon distributed therein.
- a cathode-ray tube having a screen and having a layer of light-transmitting material on its face colored to correspond to the light produced by the cathode-ray beam of said tube on the screen thereof, said light-transmitting material having particles of inert material distributed therein that produces specular diflusion 01' light.
Description
April 15, 1947. STEADMAN 2,419,177
CATHODE-RAY TUBE COATING Filed Dec. 9, 1944 HTTORNEY Patented Apr. 15, 1947 CATHODE-RAY TUBE COATING Albert Steadman, Upper Montclair, N. J., assignor to Allen B. Du Mont Laboratories, Inc., Passaic,-N. J., a corporation-of Delaware Application December 9,1944, Serial No. 567,343
This invention relates to external coatings for cathode-ray tubes which improve the contrast of the trace of the beam on the face of the tube so that the apparent brightness is increased even in the presence of strong ambient or surrounding light.
The invention may be understood from the following description in which a specific embodiment of the invention is described in connection with a somewhat diagrammatic drawing.
In carrying out the invention a coating I of light-transmitting material is applied to the outside surface of the large end of a, cathode-ray tube 2. The color of this coating I corresponds to the color emitted by the fluorescent or phos phorescent coating 3 on the inside of the tube 2. This coating I adheres tenaciously to the outer face of glass tube 2 and will not be damaged by moisture, oil or grease. At the same time such outside coating is made strong and tough enough to withstand abrasion effects which might be encountered during handling or use of the tubes upon the faces of which these coatings are applied. Inert material in finely powdered form, such as a divalent or trivalent metallic soap of the known sorts, is embodied in the coating I in amount sufficient to permit the desired degree of light transmission, while at the same time a suitable amount of specular diffusion of the transmitted light is caused to take place due to the presence of such 2 Claims. '(Cl. 250-164) A luminescent screen 3 of zinc orthosilicate is applied to the inner face of the large end of the cathode-ray tube 2 and the outer face of this tube is coated with inert material I described above. This material is tinted to a shade of green so that it passes light between 4750 angstroms and 5600 angstroms. Such a film or layer transmits about lutions of natural or synthetic resin or combinaresponding as closely as possible to those of the fluorescent or phosphorescent luminosity of the screen material that is used.
The following is given as a specific example of carrying out the invention, but the invention is not limited to this example.
82% of the fluorescent light that is produced by bombarding or scanning the screen 3 of the tube with a cathode-ray or beam. This loss of lighf is hardly noticeable in darkness, but the increase in contrast produces an increase of apparent brightness in the presence of strong ambient light. Glare is substantially or practically entirely eliminated and no change is noticed in the size of the spot that is caused by the cathoderay or beam. The coated face I of the tube 2 can be easily observed from any angle of observation within practical limits with respect to the plane of its surface.
Such coatings I are particularly useful when applied to fluorescent screened tubes that are used in television as receiving tubes. In all cases the coating is tinted in accordance with the fluorescent luminosity of the screen material 3 that is used in such tubes. For example, when a zinc sulphide-zine cadmium sulphide screen material 3 is used a preponderately white luminescence is produced so that a neutral gray tint is uite suitable for the coatin I that is used on the face of the tube 2 and has been found to be very effective since it has a practically uniform transmission characteristic over the entire range of the visible spectrum. The light transmission through the coating material I has been found to be over of the fluorescent luminosity that is produced by bombarding the fluorescent screens of such tubes with cathode-rays or beams. Th loss of light is not noticeable in the darkness, while the increase in contrast produces a considerable increase of apparent brightness when the pattern or trace on the fluorescent screen 3 is observed even in the presence of strong ambient light. Glare is also eliminated to a large extent or practically entirely and no apparent increase in the size of the light spot caused by the beam is noticeable. The pattern or picture on the face of the tube can be observed in the usual way.
With this invention cathode-ray tubes can be used without employing shields to exclude ambient light from the faces of the tubes even in surroundings where there is high ambient light.
What is claimed is: I l. A cathode-ray tube having a screen and 3 having a layer or light-transmitting material on its face colored to correspond to the light produced by the cathode-ray beam of said tube on the screen thereof, said light-transmitting material having particles of inert material capable 5 of specular difl'ractlon distributed therein.
2. A cathode-ray tube having a screen and having a layer of light-transmitting material on its face colored to correspond to the light produced by the cathode-ray beam of said tube on the screen thereof, said light-transmitting material having particles of inert material distributed therein that produces specular diflusion 01' light.
ALBERT STEADMAN.
REFERENCES crrnn The following references are of record in the file of this patent:
UNITED STATES PATENTS Date Number Name 2,124,225 Batchelor July 19, 1938 2,090,922 Von Ardenne Aug. 24, 1937 FOREIGN PATENTS Number Country Date 507,037 British Oct. 11, 1938 426,797 British Oct. 10, 1933 426,789 British Oct. 5, 1933
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US567343A US2419177A (en) | 1944-12-09 | 1944-12-09 | Cathode-ray tube coating |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US567343A US2419177A (en) | 1944-12-09 | 1944-12-09 | Cathode-ray tube coating |
Publications (1)
Publication Number | Publication Date |
---|---|
US2419177A true US2419177A (en) | 1947-04-15 |
Family
ID=24266766
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US567343A Expired - Lifetime US2419177A (en) | 1944-12-09 | 1944-12-09 | Cathode-ray tube coating |
Country Status (1)
Country | Link |
---|---|
US (1) | US2419177A (en) |
Cited By (15)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2599739A (en) * | 1950-04-12 | 1952-06-10 | American Optical Corp | Cathode-ray tube |
US2612611A (en) * | 1950-06-23 | 1952-09-30 | Rauland Corp | Cathode-ray tube |
US2612612A (en) * | 1950-06-23 | 1952-09-30 | Rauland Corp | Cathode-ray tube |
US2680205A (en) * | 1950-11-17 | 1954-06-01 | American Optical Corp | Cathode-ray tube and method of making same |
US2690554A (en) * | 1950-03-09 | 1954-09-28 | American Optical Corp | Ultraviolet filter for cathode-ray tubes |
US2706262A (en) * | 1950-07-15 | 1955-04-12 | American Optical Corp | Diffusion coated articles |
US2734142A (en) * | 1956-02-07 | Cathode ray tubes | ||
US2755413A (en) * | 1951-02-23 | 1956-07-17 | Edgar R Wagner | Gas filled projector tubes for television |
DE1005117B (en) * | 1952-05-29 | 1957-03-28 | Detag | Attachment screen for television picture tubes |
DE1008351B (en) * | 1952-12-22 | 1957-05-16 | Detag | Attachment screen for television picture tubes |
DE968937C (en) * | 1951-06-06 | 1958-04-10 | Siemens Elektrogeraete Gmbh | According to the black-and-white method, television receiver with electron beam tube for image reproduction with a screen and with an optical filter arranged in front of it |
DE1041526B (en) * | 1952-05-27 | 1958-10-23 | Siemens Elektrogeraete Gmbh | TV receiver with electron beam tube for image reproduction |
US3429997A (en) * | 1965-06-09 | 1969-02-25 | Rodenstock Optik G | Image flattening optical system for electronic image converting tube |
US3482088A (en) * | 1967-01-30 | 1969-12-02 | Hewlett Packard Co | Solid state light source |
US3814973A (en) * | 1972-09-05 | 1974-06-04 | Duro Test Corp | Electric lamps of the vibrating filament type having a conductive coating |
Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
GB507037A (en) * | ||||
GB426789A (en) * | 1933-07-06 | 1935-04-05 | Siemens Reiniger Werke Ag | Improvements in and relating to fluorescent screens |
GB426797A (en) * | 1933-09-05 | 1935-04-10 | Siemens Reiniger Werke Ag | Improvements in and relating to fluorescent screens |
US2090922A (en) * | 1932-11-21 | 1937-08-24 | Ardenne Manfred Von | Braun tube for producing television images rich in contrast |
US2124225A (en) * | 1935-02-14 | 1938-07-19 | John C Batchelor | Luminescent screen |
-
1944
- 1944-12-09 US US567343A patent/US2419177A/en not_active Expired - Lifetime
Patent Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
GB507037A (en) * | ||||
US2090922A (en) * | 1932-11-21 | 1937-08-24 | Ardenne Manfred Von | Braun tube for producing television images rich in contrast |
GB426789A (en) * | 1933-07-06 | 1935-04-05 | Siemens Reiniger Werke Ag | Improvements in and relating to fluorescent screens |
GB426797A (en) * | 1933-09-05 | 1935-04-10 | Siemens Reiniger Werke Ag | Improvements in and relating to fluorescent screens |
US2124225A (en) * | 1935-02-14 | 1938-07-19 | John C Batchelor | Luminescent screen |
Cited By (15)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2734142A (en) * | 1956-02-07 | Cathode ray tubes | ||
US2690554A (en) * | 1950-03-09 | 1954-09-28 | American Optical Corp | Ultraviolet filter for cathode-ray tubes |
US2599739A (en) * | 1950-04-12 | 1952-06-10 | American Optical Corp | Cathode-ray tube |
US2612611A (en) * | 1950-06-23 | 1952-09-30 | Rauland Corp | Cathode-ray tube |
US2612612A (en) * | 1950-06-23 | 1952-09-30 | Rauland Corp | Cathode-ray tube |
US2706262A (en) * | 1950-07-15 | 1955-04-12 | American Optical Corp | Diffusion coated articles |
US2680205A (en) * | 1950-11-17 | 1954-06-01 | American Optical Corp | Cathode-ray tube and method of making same |
US2755413A (en) * | 1951-02-23 | 1956-07-17 | Edgar R Wagner | Gas filled projector tubes for television |
DE968937C (en) * | 1951-06-06 | 1958-04-10 | Siemens Elektrogeraete Gmbh | According to the black-and-white method, television receiver with electron beam tube for image reproduction with a screen and with an optical filter arranged in front of it |
DE1041526B (en) * | 1952-05-27 | 1958-10-23 | Siemens Elektrogeraete Gmbh | TV receiver with electron beam tube for image reproduction |
DE1005117B (en) * | 1952-05-29 | 1957-03-28 | Detag | Attachment screen for television picture tubes |
DE1008351B (en) * | 1952-12-22 | 1957-05-16 | Detag | Attachment screen for television picture tubes |
US3429997A (en) * | 1965-06-09 | 1969-02-25 | Rodenstock Optik G | Image flattening optical system for electronic image converting tube |
US3482088A (en) * | 1967-01-30 | 1969-12-02 | Hewlett Packard Co | Solid state light source |
US3814973A (en) * | 1972-09-05 | 1974-06-04 | Duro Test Corp | Electric lamps of the vibrating filament type having a conductive coating |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US2419177A (en) | Cathode-ray tube coating | |
SU1409140A3 (en) | Image display apparatus | |
US3114065A (en) | Color image reproducer | |
US2435436A (en) | Cathode-ray tube screen | |
US2177360A (en) | Optical image intensifier | |
US2243828A (en) | Luminescent screen | |
US2423830A (en) | Cathode-ray screen having contrasting colors and unlike rates of decay of luminescence | |
US2090922A (en) | Braun tube for producing television images rich in contrast | |
US3873868A (en) | Display tube with color selective filtration | |
US2485561A (en) | Cathode-ray tube | |
US2567714A (en) | Cathode-ray tube | |
US2616057A (en) | Black screen television cathode-ray tube | |
US2137118A (en) | Fluorescent screen | |
US2418779A (en) | Alkali metal halide and luminescent screens of substantially coincident spectral absorption | |
EP0836215B1 (en) | Color image receiving tube | |
US3946267A (en) | Plural filter system cooperating with cathode ray display with lanthanum host phosphor emissive in two colors | |
US2521571A (en) | Projection screen | |
US2991383A (en) | Tri-color phosphor screens of the mosaic variety | |
US2227070A (en) | Projection system | |
US5942848A (en) | Color display device with phosphor regions for emitting red, blue and green light through red-blue color-filler layers and apertures in a black-matrix layer | |
US5065071A (en) | Monochrome CRT with interference filter having filter layer with reduced transmission and projection color TV incorporating same | |
US2915661A (en) | Color television screen | |
DE1512397B2 (en) | LIGHT SCREEN FOR COLOR IMAGE PLAYBACK TUBES | |
US5196763A (en) | Mixed green light-emitting phosphor, and a cathode ray tube using this phosphor | |
US2051632A (en) | Television receiving system |