GB636250A - Improvements in or relating to television and like pick-up tubes - Google Patents
Improvements in or relating to television and like pick-up tubesInfo
- Publication number
- GB636250A GB636250A GB23359/46A GB2335946A GB636250A GB 636250 A GB636250 A GB 636250A GB 23359/46 A GB23359/46 A GB 23359/46A GB 2335946 A GB2335946 A GB 2335946A GB 636250 A GB636250 A GB 636250A
- Authority
- GB
- United Kingdom
- Prior art keywords
- target
- electrons
- screen
- photo
- gun
- 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
Links
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
- H01J31/00—Cathode ray tubes; Electron beam tubes
- H01J31/08—Cathode ray tubes; Electron beam tubes having a screen on or from which an image or pattern is formed, picked up, converted, or stored
- H01J31/26—Image pick-up tubes having an input of visible light and electric output
- H01J31/28—Image pick-up tubes having an input of visible light and electric output with electron ray scanning the image screen
- H01J31/34—Image pick-up tubes having an input of visible light and electric output with electron ray scanning the image screen having regulation of screen potential at cathode potential, e.g. orthicon
- H01J31/36—Tubes with image amplification section, e.g. image-orthicon
Landscapes
- Image-Pickup Tubes, Image-Amplification Tubes, And Storage Tubes (AREA)
Abstract
636,250. Cathode-ray tubes. RADIO CORPORATION OF AMERICA. Aug. 6, 1946, No. 23359. Convention date, Aug. 3, 1945. [Class 39 (i)] An electric discharge pick-up tube of the orthicon type in which the beam velocity is reduced to substantially zero in the vicinity of the target has means on the gun-side of the target producing a potential pattern corresponding to the charge image formed on the remote side of the target which pattern controls the returning beam, and grid means preventing collection of electrons, by the actual target. The tube comprises an electron gun 2, a target 3 and a photo cathode 4. The end 8 of an anode 7 forms the first dynode of the electron multiplier, and there are the electrode 10, wall coating 11, deflecting unit 12 adjustable by a rod 13, compensating coil 14 and a focusing coil 15. The multiplier consists of additional fan-like dynodes 16, 17, 18, 19 and a collecting screen electrode 20 connected to the grid of an amplifier tube 20<1>. The photocathode 4 is a semi-transparent coating of lightsensitive emissive material. A frame 23 supports the thin glass target 3 and a collecting screen 24. Between a decelerating ring 25 and the target 3 is the discharge screen 27 which is at zero or gun potential. The electrons in the beam 9 do not therefore land on the target 3 in substantial quantities but on the screen 27 which is under the potential pattern of the charge image on the target 3. The scene focused on the photo-cathode 4 produces electrons which are projected at high velocities through screen 24 on to the unscanned side of target 3 liberating secondary electrons and leaving a charge image on the target. The secondary electrons proceed to collecting- screen 24 but enough rain down on the elemental areas of the charge pattern between frames of moving pictures to discharge these areas. With stationary pictures, the charges build up to saturation. The electrons of the modulated beam, which do not fall on the targets 27 or 3 return towards the gun and fall on the first dynode of the multiplier and are finally utilized in the circuit exemplified by the amplifier 20<1>. The multiplier unit may be omitted. By controlling the potential pattern, the charge image for the light regions of the picture can be made to attract the electrons towards the mesh openings of the screen 27, giving maximum multiplier current for the white regions, stated to improve the signal/ noise relationship. If the screen 27 is biassed 2-5 volts positive relative to the gun cathode, secondary electrons are emitted under impact of the beam electrons and accelerate to the multipliers in greater numbers for the bright areas than for the dark areas and substantially no beam electrons land on the relatively negative glass target. Image amplification may be obtained by the arrangement shown in Fig. 4, in which the focussing coil 15 is subdivided to allow light to fall on the sensitized screens 27, 27<1>, 27<11>. Photo-electrons liberated from the screens are proportional to the charge image pattern induced on the targets 3, 3<1>, 3<11> by liberation of secondary electrons arising from the impacting photo-electrons. The amplified photo-electrons from screen 27<1> fall on target 3<1> to produce further amplification of photo-electrons from screen 27<1> and so on. The screens 27<1> and 27<11> may be made thermally emissive, in the form of stranded screens and so avoid further flooding by light and the consequential division of the focusing coil. The .Specification as open to inspection under Sect. 91 also describes the omission of the screen 27 (Fig. 4) and the coating of target 3<11> with a fluorescent material. This subjectmatter does not appear in the Specification as accepted.
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US608663A US2537250A (en) | 1945-08-03 | 1945-08-03 | Electronic tube |
Publications (1)
Publication Number | Publication Date |
---|---|
GB636250A true GB636250A (en) | 1950-04-26 |
Family
ID=24437481
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
GB23359/46A Expired GB636250A (en) | 1945-08-03 | 1946-08-06 | Improvements in or relating to television and like pick-up tubes |
Country Status (2)
Country | Link |
---|---|
US (1) | US2537250A (en) |
GB (1) | GB636250A (en) |
Families Citing this family (10)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2747133A (en) * | 1950-07-05 | 1956-05-22 | Rca Corp | Television pickup tube |
US2777970A (en) * | 1950-10-03 | 1957-01-15 | Paul K Weimer | Television camera storage tube |
US2792514A (en) * | 1950-12-07 | 1957-05-14 | Rca Corp | Orthicon electrode structure |
US2802962A (en) * | 1951-06-01 | 1957-08-13 | Sheldon Edward Emanuel | Neutron storage tube |
US2840755A (en) * | 1952-03-21 | 1958-06-24 | Westinghouse Electric Corp | Large storage low noise image tube |
US2912614A (en) * | 1953-11-06 | 1959-11-10 | Emi Ltd | Circuit arrangements embodying electron discharge devices |
GB807992A (en) * | 1954-07-03 | 1959-01-28 | Emi Ltd | Improvements in or relating to cathode ray image pick-up devices |
US3005046A (en) * | 1958-05-19 | 1961-10-17 | Diamond Power Speciality | Television camera |
US3566019A (en) * | 1966-09-19 | 1971-02-23 | Richard F Koch | Combined electron image tube and vidicon |
US3525010A (en) * | 1968-04-01 | 1970-08-18 | Teltron Inc | Image orthicon beam control circuit |
Family Cites Families (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
GB485646A (en) * | 1935-08-14 | 1938-05-20 | Farnsworth Television Inc | Charge storage dissector tube |
GB504927A (en) * | 1937-10-28 | 1939-04-28 | James Dwyer Mcgee | Improvements in or relating to electron permeable electrodes |
US2407906A (en) * | 1942-08-27 | 1946-09-17 | Rca Corp | Low velocity television transmitting apparatus |
NL83415C (en) * | 1944-09-16 |
-
1945
- 1945-08-03 US US608663A patent/US2537250A/en not_active Expired - Lifetime
-
1946
- 1946-08-06 GB GB23359/46A patent/GB636250A/en not_active Expired
Also Published As
Publication number | Publication date |
---|---|
US2537250A (en) | 1951-01-09 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US2652515A (en) | Negative charge image television transmission tube | |
GB636250A (en) | Improvements in or relating to television and like pick-up tubes | |
US2462569A (en) | Television receiving tube with storage properties | |
US2458205A (en) | Televison pickup tube | |
US2618761A (en) | Negative stored charge pickup tube | |
US5101100A (en) | Streak camera operable with low deflection voltage | |
GB740442A (en) | Improvements in or relating to television apparatus | |
US2733292A (en) | System fqb correcting-the-equilibrium | |
US2777970A (en) | Television camera storage tube | |
US2373396A (en) | Electron discharge device | |
US2723360A (en) | Image orthicon | |
US2377972A (en) | Television transmitting system | |
US2465667A (en) | Method of and means for controlling the beam current in television camera tubes | |
GB743431A (en) | Improvements in or relating to picture and/or picture signal producing electron discharge tubes | |
US2324504A (en) | Television transmitting system | |
US2619531A (en) | Pickup tube for television and the like | |
US2617954A (en) | Pickup tube | |
US2237679A (en) | Electron discharge device | |
US2520240A (en) | Cathode-ray tube | |
US2563490A (en) | Cathode arrangement fob television | |
US2792514A (en) | Orthicon electrode structure | |
US2870370A (en) | Photothermionic spectrum converter | |
US2227092A (en) | Cathode ray tube | |
US3047757A (en) | Image intensifier devices | |
US3106605A (en) | Apparatus for generating picture signals |