EP0162972B1 - Tube cathodique de projection - Google Patents

Tube cathodique de projection Download PDF

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Publication number
EP0162972B1
EP0162972B1 EP84200785A EP84200785A EP0162972B1 EP 0162972 B1 EP0162972 B1 EP 0162972B1 EP 84200785 A EP84200785 A EP 84200785A EP 84200785 A EP84200785 A EP 84200785A EP 0162972 B1 EP0162972 B1 EP 0162972B1
Authority
EP
European Patent Office
Prior art keywords
window
cooling
space
tube
picture
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
Application number
EP84200785A
Other languages
German (de)
English (en)
Other versions
EP0162972A1 (fr
Inventor
Albert Dr. Comberg
Alwin Knops
Heinrich Oepen
Dieter Wädow
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.)
Koninklijke Philips NV
Original Assignee
Philips Patentverwaltung GmbH
Philips Gloeilampenfabrieken NV
Koninklijke Philips Electronics NV
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
Application filed by Philips Patentverwaltung GmbH, Philips Gloeilampenfabrieken NV, Koninklijke Philips Electronics NV filed Critical Philips Patentverwaltung GmbH
Priority to EP84200785A priority Critical patent/EP0162972B1/fr
Priority to DE8484200785T priority patent/DE3474484D1/de
Priority to US06/738,107 priority patent/US4651047A/en
Priority to ES543605A priority patent/ES8608732A1/es
Priority to DD85276814A priority patent/DD237948A5/de
Priority to JP60115507A priority patent/JPH067460B2/ja
Priority to KR1019850003812A priority patent/KR920010664B1/ko
Publication of EP0162972A1 publication Critical patent/EP0162972A1/fr
Application granted granted Critical
Publication of EP0162972B1 publication Critical patent/EP0162972B1/fr
Expired legal-status Critical Current

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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
    • H01J31/10—Image or pattern display tubes, i.e. having electrical input and optical output; Flying-spot tubes for scanning purposes
    • 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
    • H01J29/86—Vessels; Containers; Vacuum locks
    • H01J29/861—Vessels or containers characterised by the form or the structure thereof
    • 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
    • H01J29/006—Arrangements for eliminating unwanted temperature effects

Definitions

  • the invention relates to a projection television picture tube with an evacuated casing with a picture window, which is provided with a screen on the inside and in front of which a translucent second window is arranged on the outside, the space between the picture window and the second window of at least one inflow opening flows to at least one outflow opening, a cooling liquid.
  • Such a picture tube is known from the published Dutch patent application 8 003 360.
  • a raster is described on the screen, which usually has a phosphor layer or a pattern of different phosphors.
  • Electron bombardment increases the temperature of the phosphor, which reduces the light output of the screen ("thermal quenching").
  • This phenomenon occurs in particular in picture tubes for projection television, with electron beams being scanned with large beam currents in order to obtain the required high luminance levels of the screens.
  • the temperature of the image window increases and a temperature gradient arises at the image window. This gradient causes a mechanical stress in which e.g. Picture window made of glass.
  • thermal stress With a high electron beam current and consequently high thermal stress, this can lead to a break in the image window.
  • thermal stress thermo stress
  • the space between the image window and the second window filled with coolant is surrounded at the top, bottom and side by a metal heat sink serving as a spacer and acting as a heat radiator. Due to the temperature rise of the picture window, the cooling liquid warmed by the picture window moves upwards along the picture window and downwards along the second window, whereby the heat is also dissipated from the center of the picture window via the heat sink.
  • the heat is dissipated mainly by conduction to the second window.
  • the liquid flow described above occurs, with an associated but ineffective additional cooling by the heat sink.
  • the cooling liquid is exposed to cooling outside the room.
  • the cooling liquid is supplied from the top of the room through pipes or hoses and through a cooling chamber to the underside of the room, namely through flow due to temperature differences in the cooling liquid.
  • a disadvantage of such a tube is that when the tube is replaced in a projector, the cooling liquid has to be removed and the hoses or tubes have to be detached from the picture tube.
  • the object of the invention is to create a picture tube with a more effective cooling system based on the prior art described above, so that effective cooling results in a power of up to 40 W.
  • the invention also has the task of creating a picture tube with an essentially homogeneous temperature distribution over the screen.
  • the invention also has the task of creating a picture tube with cooling without additional tubes and individual heat exchangers.
  • a picture tube of the type described at the outset according to the invention is characterized in that a cooling jacket is arranged at the height of the windows and around the space mentioned, which is provided with at least one channel and a pump with pump connecting pieces which hold the cooling liquid lead from the outflow to the inflow opening or openings of said space.
  • the supply of coolant is to be dimensioned such that its heat capacity is sufficient to dampen short-term temperature fluctuations due to the changing load on the screen.
  • the coolant With this cooling, the coolant generally flows laminarly along the warm picture window and absorbs heat there.
  • the coolant is then pumped from the outflow opening (s) through the channel in the cooling jacket where the cooling liquid releases its heat to the cooling jacket. Due to the circulation of the liquid, better and more homogeneous temperature regulation is achieved than with the known cooling systems with a simple cooling chamber. This further reduces the tension in the glass of the picture tube.
  • Another advantage of the picture tube according to the invention is that no external tubes and hoses are necessary for connection to a heat exchanger and the pump, which makes it much easier to mount the tube in a (projection) arrangement for displaying images.
  • the cooling in a picture tube according to the invention is considerably more effective than the cooling described in the first exemplary embodiment of the already mentioned Dutch patent application 8003360, because the cooling liquid between the picture window and the second window is pumped mainly in only one direction and is cooled in the cooling jacket.
  • the pump can be located anywhere in the channel between the outflow opening and the inflow opening.
  • One of the pump connections is preferably connected to an inflow or outflow opening or openings, the other pump connection opening into the channel.
  • the inflow or outflow opening or openings pass into a substantially smooth transition into an initially widening chamber, the chamber being connected to one of the pump connections.
  • At least the outer wall of the cooling jacket is preferably made of metal and is optionally provided with cooling fins. It is possible to force the ribs to cool with air.
  • a preferred embodiment of a picture tube according to the invention is characterized in that the space mentioned, through which the cooling liquid flows, through two seals extending parallel to the direction of flow in the space, e.g. Glass or metal strips, between the picture window and the second window is limited. If two stripes are used on the two sides of the image window, they can also act as spacers between the image window and the second window.
  • the second window prefferably be the first element of the optical lens system of the image display device.
  • the picture window is attached to the cone of the tube with a glass enamel, it is advantageous to arrange the adhesive seam formed in this way in the wall of the channel. As a result, the coolant also flows around this heat-sensitive point, thereby avoiding the occurrence of thermal stresses.
  • FIG. 1 a partially cut side view of a picture tube according to the invention is shown.
  • This picture tube contains a shell 1, which consists of a neck 2 and a cone 3 and is closed with a picture window 4.
  • a screen 5 is arranged on the inside of this picture window.
  • a translucent second window 6 is provided essentially parallel to the outside of the image window 4.
  • a cooling jacket 8 is provided around the tube end at the level of the windows 4 and 6 and the space 7 lying between them.
  • This cooling jacket contains a channel 9 through an outer wall 10 of the cooling jacket, the side edge 11 of the second window 6, a glass strip 12 (see FIG. 2), the edge of the picture window 4, the edge of the cone 14 and the rear wall 15 of the cooling jacket is limited.
  • any expansion differences between the outer wall 10 and the tube end can be compensated for by the flexible rear wall 15 of the cooling jacket.
  • a pump 16 with a motor M and a pump part P with two connections 17 and 18 is arranged in the cooling jacket 8.
  • the pump connector 18 is connected via a pipe 19 to an expanding chamber 20 which adjoins the inlet opening 21 of the room 7. This transition should be as smooth or smooth as possible in order to avoid turbulence and the associated refractive index fluctuations in the cooling liquid in space 7.
  • the outer wall 10 of the cooling jacket 8 is zigzag-shaped, whereby cooling fins are formed.
  • the outer wall 10 suitably consists of aluminum or a material with a similarly high thermal conductivity. Silicone rubber is preferably used as the sealing compound 22 since it has great plasticity over a wide temperature range.
  • the space 7, the channel 9 and the pump 16 are filled with cooling liquid (for example water or an ethylene glycol / water mixture with a lower melting point and a higher boiling point than water).
  • cooling liquid for example water or an ethylene glycol / water mixture with a lower melting point and a higher boiling point than water.
  • the heat generated in the screen is absorbed by the coolant through the image window.
  • the warm coolant is conveyed from the room 7 into the channel 9 by the pump.
  • the cooling liquid partially emits the heat absorbed therein by the wall 10 and the rear wall 15 of the cooling jacket and is pumped back into the room 7 by the pump.
  • the direction of flow of the coolant is indicated by arrows; the pump direction can of course also be reversed.
  • the tube also has a tube base 23 with connecting pins 24.
  • FIG. 2 shows a partially cut side view perpendicular to the view according to FIG. 1.
  • the reference numerals correspond to those in FIG. 1.
  • FIG. 1 shows a front view (front view) of the tube according to FIGS. 1 and 2.
  • the reference numerals again correspond to those in FIG. 1.
  • the position of the seals and the flow directions indicated by arrows can be seen particularly clearly in FIG.
  • the cooling jacket 8 is shown here in a circle, but, like the picture window, it can also be essentially rectangular.
  • the channel 9 can also consist of two sub-channels.
  • the picture tubes in a picture display device need not be arranged horizontally (picture window vertical), they can also be arranged and operated more or less vertically (picture window horizontal).

Landscapes

  • Cathode-Ray Tubes And Fluorescent Screens For Display (AREA)
  • Projection Apparatus (AREA)
  • Vessels, Lead-In Wires, Accessory Apparatuses For Cathode-Ray Tubes (AREA)
  • Common Detailed Techniques For Electron Tubes Or Discharge Tubes (AREA)

Claims (6)

1. Tube image à projection comportant une enveloppe (1) vidée d'air et munie d'une fenêtre image (4), dont la face intérieure est munie d'un écran image (5) et devant laquelle est disposée, du côté extérieur, une deuxième fenêtre transparente (6), un liquide de refroidissement circulant à travers l'espace (7) compris entre la fenêtre image et la deuxième fenêtre à partir d'au moins un orifice d'admission (21) vers au moins un orifice d'évacuation, caractérisé en ce qu'à la hauteur de la fenêtre et autour dudit espace est disposée une chemise réfrigérante (8), qui est munie d'au moins un canal (9) et d'au moins une pompe (16) comportant des raccords (17, 18) assurant l'amenée du liquide de refroidissement à partir de l'orifice ou des orifices d'évacuation vers l'orifice ou les orifices d'évacuation dudit espace.
2. Tube image selon la revendication 1, caractérisé en ce que l'un des raccords de la pompe est raccordé à un (des) orifice(s) d'admission ou d'évacuation et que l'autre raccord débouche dans le canal.
3. Tube image selon la revendication 2, caractérisé en ce que l'orifice ou les orifices d'admission ou d'évacuation se raccorde(nt) d'une façon essentiellement coulante à une chambre qui s'évase initialement, et qui est raccordée à l'un des raccords de la pompe.
4. Tube image selon la revendication 1, 2 ou 3, caractérisé en ce que la chemise réfrigérante est essentiellement constituée par du métal et, le cas échéant, munie d'ailettes de refroidissement.
5. Tube image selon l'une des revendications précédentes, caractérisé en ce que ledit espace est limité des deux côtés par deux joints (12) parallèles à la direction de circulation du liquide contenu dans l'espace disposé entre les deux fenêtres .
6. Tube image selon l'une des revendications précédentes, caractérisé en ce que la fenêtre image est fixée à l'aide d'un émail vitrifié au cône du tube, la couture collée ainsi formée étant disposée dans la paroi du canal.
EP84200785A 1984-06-01 1984-06-01 Tube cathodique de projection Expired EP0162972B1 (fr)

Priority Applications (7)

Application Number Priority Date Filing Date Title
EP84200785A EP0162972B1 (fr) 1984-06-01 1984-06-01 Tube cathodique de projection
DE8484200785T DE3474484D1 (en) 1984-06-01 1984-06-01 Projection cathode ray tube
US06/738,107 US4651047A (en) 1984-06-01 1985-05-24 Projection television display tube
ES543605A ES8608732A1 (es) 1984-06-01 1985-05-29 Un tubo de imagen de proyeccion de television
DD85276814A DD237948A5 (de) 1984-06-01 1985-05-30 Projektionsfernsehbildroehre
JP60115507A JPH067460B2 (ja) 1984-06-01 1985-05-30 投写型テレビジヨン受像管
KR1019850003812A KR920010664B1 (ko) 1984-06-01 1985-05-31 냉각 시스템을 갖는 프로젝션 텔레비젼 표시관

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
EP84200785A EP0162972B1 (fr) 1984-06-01 1984-06-01 Tube cathodique de projection

Publications (2)

Publication Number Publication Date
EP0162972A1 EP0162972A1 (fr) 1985-12-04
EP0162972B1 true EP0162972B1 (fr) 1988-10-05

Family

ID=8192448

Family Applications (1)

Application Number Title Priority Date Filing Date
EP84200785A Expired EP0162972B1 (fr) 1984-06-01 1984-06-01 Tube cathodique de projection

Country Status (7)

Country Link
US (1) US4651047A (fr)
EP (1) EP0162972B1 (fr)
JP (1) JPH067460B2 (fr)
KR (1) KR920010664B1 (fr)
DD (1) DD237948A5 (fr)
DE (1) DE3474484D1 (fr)
ES (1) ES8608732A1 (fr)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE10335320A1 (de) * 2003-08-01 2005-03-03 Siemens Ag Röntgenstrahler und Röntgengerät

Families Citing this family (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3475140D1 (en) * 1984-06-01 1988-12-15 Philips Nv Projection cathode ray tube and image display device provided with such a tube
DE3510021A1 (de) * 1985-03-20 1986-09-25 Philips Patentverwaltung Gmbh, 2000 Hamburg Projektionsfernsehbildroehre
JPH081779B2 (ja) * 1985-07-05 1996-01-10 株式会社日立製作所 投射形ブラウン管
NL8602007A (nl) * 1986-08-06 1988-03-01 Philips Nv Beeldbuis en kleurentelevisie-projectie inrichting voorzien van zulk een beeldbuis.
CA2168954A1 (fr) * 1994-06-07 1995-12-14 Patrick Verschueren Lampe a decharge a haute pression et bouclier thermique pour une telle lampe
US6550521B1 (en) 2000-05-30 2003-04-22 Visual Structures, Inc. Seamless screen videowall
KR20030080769A (ko) * 2002-04-10 2003-10-17 삼성에스디아이 주식회사 투사형 음극선관의 냉각장치
BRPI0503983A (pt) * 2004-07-29 2006-04-11 Nat Starch Chem Invest uso de um produto de amido inibido ou reticulado
EP2103915B1 (fr) * 2008-03-17 2016-11-16 Siemens Aktiengesellschaft Appareil et procédé pour déterminer la fréquence de résonance d'une tour d'éolienne
US8152341B2 (en) * 2011-02-04 2012-04-10 Switch Bulb Company, Inc. Expandable liquid volume in an LED bulb
US8686623B2 (en) 2012-02-01 2014-04-01 Switch Bulb Company, Inc. Omni-directional channeling of liquids for passive convection in LED bulbs
KR101988014B1 (ko) 2012-04-18 2019-06-13 삼성디스플레이 주식회사 어레이 기판의 제조 방법 및 이에 사용되는 제조 장치
US10117364B2 (en) 2016-02-07 2018-10-30 Display Logic USA Inc. Display device with optically clear fluid disposed between display panel and display cover
EP3503700A1 (fr) * 2017-12-19 2019-06-26 Skidata Ag Dispositif d'affichage pour dispositifs de contrôle d'accès, machines de vente et machines de paiement et dispositifs de signalisation numérique

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US2124224A (en) * 1935-02-01 1938-07-19 John C Batchelor Electronic tube
GB527843A (en) * 1938-04-22 1940-10-17 Loewe Opta Gmbh Cathode ray tube
US3531674A (en) * 1968-07-05 1970-09-29 Raytheon Co Cathode ray tube with cooling means for the fluorescent screen
US3914010A (en) * 1974-11-25 1975-10-21 Us Army Liquid long-wave pass filter for high intensity light source
JPS597731Y2 (ja) * 1979-06-07 1984-03-09 ソニー株式会社 陰極線管装置
JPS56119251U (fr) * 1980-02-12 1981-09-11
JPS58154146A (ja) * 1982-03-10 1983-09-13 Sony Corp 液冷式陰極線管
NL8201136A (nl) * 1982-03-19 1983-10-17 Philips Nv Beeldbuis.
JPS58218734A (ja) * 1982-06-14 1983-12-20 Sony Corp 陰極線管装置
CA1225453A (fr) * 1982-12-22 1987-08-11 Harry Howden Dispositif pour refroidir l'ecran du tube cathodique d'un projecteur de television
NL8300114A (nl) * 1983-01-13 1984-08-01 Philips Nv Beeldbuis.
JPS59157938A (ja) * 1983-02-24 1984-09-07 Sony Corp 陰極線管装置

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE10335320A1 (de) * 2003-08-01 2005-03-03 Siemens Ag Röntgenstrahler und Röntgengerät
DE10335320B4 (de) * 2003-08-01 2005-11-03 Siemens Ag Röntgenstrahler und Röntgengerät

Also Published As

Publication number Publication date
JPS60262337A (ja) 1985-12-25
KR920010664B1 (ko) 1992-12-12
EP0162972A1 (fr) 1985-12-04
KR860000778A (ko) 1986-01-30
JPH067460B2 (ja) 1994-01-26
US4651047A (en) 1987-03-17
DE3474484D1 (en) 1988-11-10
ES543605A0 (es) 1986-06-16
DD237948A5 (de) 1986-07-30
ES8608732A1 (es) 1986-06-16

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