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EP0017259A1 - Process for making luminescent screens for colour display tubes and device for carrying out this process - Google Patents

Process for making luminescent screens for colour display tubes and device for carrying out this process Download PDF

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Publication number
EP0017259A1
EP0017259A1 EP80200002A EP80200002A EP0017259A1 EP 0017259 A1 EP0017259 A1 EP 0017259A1 EP 80200002 A EP80200002 A EP 80200002A EP 80200002 A EP80200002 A EP 80200002A EP 0017259 A1 EP0017259 A1 EP 0017259A1
Authority
EP
European Patent Office
Prior art keywords
light
exposure
place
aperture
front glass
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.)
Withdrawn
Application number
EP80200002A
Other languages
German (de)
French (fr)
Inventor
Bruno Fischer
Rainer Vollath
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.)
International Standard Electric Corp
Original Assignee
International Standard Electric Corp
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 International Standard Electric Corp filed Critical International Standard Electric Corp
Publication of EP0017259A1 publication Critical patent/EP0017259A1/en
Withdrawn legal-status Critical Current

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Classifications

    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01JELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J9/00Apparatus or processes specially adapted for the manufacture, installation, removal, maintenance of electric discharge tubes, discharge lamps, or parts thereof; Recovery of material from discharge tubes or lamps
    • H01J9/20Manufacture of screens on or from which an image or pattern is formed, picked up, converted or stored; Applying coatings to the vessel
    • H01J9/22Applying luminescent coatings
    • H01J9/227Applying luminescent coatings with luminescent material discontinuously arranged, e.g. in dots or lines
    • H01J9/2271Applying luminescent coatings with luminescent material discontinuously arranged, e.g. in dots or lines by photographic processes
    • H01J9/2272Devices for carrying out the processes, e.g. light houses

Definitions

  • the invention relates to a method for producing fluorescent screens for color picture tubes, in which a light-sensitive layer is exposed through the shadow mask of the tube.
  • FIG. 1 A device for carrying out such a method is shown in FIG. 1 in its essential components.
  • a light-sensitive phosphor layer 2 On the front glass 1 there is a light-sensitive phosphor layer 2, which is illuminated by the light mask 4 through the shadow mask 3.
  • the light rays are designated 5.
  • the beam path of the light is simulated by a lens 6 so that it corresponds to the path of the electron beams in the finished tube.
  • Fluorescent strips of essentially constant width are to be achieved on the screen. However, the transparency of the mask changes significantly e.g. from their center to the edge.
  • the thickness and temperature of the light-sensitive phosphor layer cast in the shielding process depend on the location of the shield. All of this means that a filter 7 is also used, which is arranged on the lens 6 or directly below it, or, as shown in FIG. 1, directly above it fluctuating width can be achieved. As a rule, the transparency of the filter is considerably higher at the edge than in the middle.
  • the filter usually consists of a gelatin-soot layer on glass.
  • the production of such a layer is described in detail in DE-OS 20 36 684.
  • fluorescent strips When exposed through such a filter, fluorescent strips are included, the width compliance of which is completely satisfactory, but are the edges of the strips are fairly torn, which in unfavorable cases gives rise to considerable fluctuations in color when the tube is in operation, for example in a uniform white image.
  • the solution to the problem can be found in the first claim.
  • the exposure intensity is changed in that the exposure time varies from place to place and the light intensity is no longer influenced by a filter with a constant exposure time from place to place as was previously the case.
  • the method is implemented in that a rotating diaphragm with a diaphragm opening that increases radially outwards is attached in the beam path.
  • a significant advantage of the method is that the mechanical aperture maintains its transmission characteristics indefinitely, while soot-gelatin filters age quickly.
  • the exposure time is shortened considerably by the method according to the invention, typically to less than half compared to a method with a gelatin-soot filter.
  • the aperture B rotates around the point labeled M, which lies on the axis of the central exposure beam.
  • the light can shine through unhindered.
  • the area cut out of the hatched aperture material preferably a steel sheet, increases with increasing angle of rotation. This is when rotating the aperture in the middle greatly weakens the light on average, while the light rays are increasingly only interrupted to the outside for a shorter time and thus a larger amount of light passes through during the exposure time.
  • the aperture is designed in such a way that the amount of light passing through, which is dependent on the location, coincides on average over time with that of the conventional gelatin-soot filter.
  • a weak gelatin-soot correction filter or any other filter or an aperture arrangement can of course be used in addition to the rotating aperture according to the invention.
  • the diaphragms are introduced with different times in different places in the beam path.
  • the aperture is attached in the exposure device at the point at which the gelatin-soot filter was previously arranged.
  • the aperture according to the invention would therefore be in place of the filter 7.
  • the rotating aperture is inserted, for example, on its outermost circumference in a rotatable and drivable holder.
  • a gelatin-soot filter When the light-sensitive layer of the green phosphor is exposed, a gelatin-soot filter must be used for about 20 seconds in order to obtain phosphor strips of the desired width and adhesive strength.
  • the exposure time is only 10 seconds.
  • the speed of the diaphragm is typically 100-200 rpm, i.e. during the 10 sec the aperture turns 17 - 33 times.

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  • Engineering & Computer Science (AREA)
  • Manufacturing & Machinery (AREA)
  • Formation Of Various Coating Films On Cathode Ray Tubes And Lamps (AREA)

Abstract

Eine durch Licht aushärtbare, auf das Frontglas (1) einer Farbbildröhre aufgebrachte, Leuchtstoff enthaltende Schicht (2) wird mit ortsabhängiger Belichtungsmenge belichtet, um scharf berandete Leuchtstoffstreifen mit nur geringen Breiteschwankungen zu erzielen. Die unterschiedliche Belichtung erfolgt durch Blenden (7), welche mit unterschiedlichen Verweilzeiten in das Belichtungstrahlenbündel (5) eingebracht werden. Bevorzugte Ausführungsform ist eine rotierende Blende mit ortsabhängiger Blendenöffnung.A light-curable layer (2) containing fluorescent material applied to the front glass (1) of a color picture tube is exposed with a location-dependent amount of exposure in order to achieve sharply edged fluorescent strips with only slight fluctuations in width. The different exposure takes place through diaphragms (7) which are introduced into the exposure beam (5) with different dwell times. A preferred embodiment is a rotating diaphragm with a location-dependent diaphragm opening.

Description

Die Erfindung betrifft ein Verfahren zur Herstellung von Leuchtschirmen für Farbbildröhren, bei dem eine lichtempfindliche Schicht durch die Schattenmaske der Röhre hindurch belichtet wird.The invention relates to a method for producing fluorescent screens for color picture tubes, in which a light-sensitive layer is exposed through the shadow mask of the tube.

Bei einem solchen Verfahren, wie es z.B. in der DE-OS 24 40 575 beschrieben ist, sollen Leuchtstoffstreifen mit nur innerhalb geringer Grenzen schwankender Streifenbreite erzielt werden. Eine Vorrichtung zur Durchführung eines solchen Verfahrens ist in Figur 1 in ihren wesentlichen Bauteilen dargestellt. Auf dem Frontglas 1 befindet sich eine lichtempfindliche Leuchtstoffschicht 2, welche durch die Schattenmaske 3 von der Lichtquelle 4 beleuchtet wird. Die Lichtstrahlen sind mit 5 bezeichnet. Durch eine Linse 6 wird der Strahlengang des Lichts so nachgebildet, daß der dem Weg der Elektronenstrahlen in der fertigen Röhre entspricht. Auf dem Schirm sollen Leuchtstoff streifen im wesentlichen konstanter Breite erzielt werden. Die Transparenz der Maske ändert sich jedoch erheblich z.B. von ihrer Mitte zum Rand hin. Außerdem sind die Dicke und Temperatur der im Beschirmverfaairen aufgegossenen lichtempfindlichen Leuchtstoffschicht abhängig vom Schirmort. Dies alles führt dazu, daß noch ein Filter 7 verwendet wird, welches auf der Linse 6 oder direkt unter ihr, oder wie in Figur 1 gezeichnet direkt über ihr angeordnet ist.Dieses Filter beeinflußt die Intensität der Lichtstrahlen so, daß im Endeffekt Leuchtstoffstreifen nur wenig schwankender Breite erzielt werden. In der Regel ist die Transparenz des Filters am Rande erheblich höher als in der Mitte.In such a process as e.g. In DE-OS 24 40 575 is described, fluorescent strips are to be achieved with a fluctuating strip width only within small limits. A device for carrying out such a method is shown in FIG. 1 in its essential components. On the front glass 1 there is a light-sensitive phosphor layer 2, which is illuminated by the light mask 4 through the shadow mask 3. The light rays are designated 5. The beam path of the light is simulated by a lens 6 so that it corresponds to the path of the electron beams in the finished tube. Fluorescent strips of essentially constant width are to be achieved on the screen. However, the transparency of the mask changes significantly e.g. from their center to the edge. In addition, the thickness and temperature of the light-sensitive phosphor layer cast in the shielding process depend on the location of the shield. All of this means that a filter 7 is also used, which is arranged on the lens 6 or directly below it, or, as shown in FIG. 1, directly above it fluctuating width can be achieved. As a rule, the transparency of the filter is considerably higher at the edge than in the middle.

Das Filter besteht üblicherweise aus einer Gelatine-Ruß-Schicht auf Glas. Die Herstellung einer solchen Schicht ist ausführlich in der DE-OS 20 36 684 beschrieben.The filter usually consists of a gelatin-soot layer on glass. The production of such a layer is described in detail in DE-OS 20 36 684.

Bei Belichtung durch ein derartiges Filter werden Leuchtstoffstreifen enthalten, deren Breiteneinhaltung völlig zufriedenstellend ist, jedoch sind die Ränder der Streifen ziemlich zerrissen, was in ungünstigen Fällen im Betrieb der Röhre zu erheblichen Farbortschwankungen z.B. in einem einheitlich weißen Bild Anlaß gibt.When exposed through such a filter, fluorescent strips are included, the width compliance of which is completely satisfactory, but are the edges of the strips are fairly torn, which in unfavorable cases gives rise to considerable fluctuations in color when the tube is in operation, for example in a uniform white image.

Es bestand daher die Aufgabe, ein Belichtungsverfahren anzugeben, mit dem scharf berandete Leuchtstoffstreifen mit nur geringen Breiteschwankungen erzielbar sind.It was therefore the task of specifying an exposure method with which sharply edged fluorescent strips can be achieved with only slight fluctuations in width.

Die Lösung der Aufgabe ist dem ersten Anspruch entnehmbar, Die Belichtungsintensität wird dadurch verändert, daß die Belichtungsdauer von Ort zu Ort schwankt und nicht mehr wie bisher Üblich die Lichtstärke bei konstanter Belichtungsdauer von Ort zu Ort durch ein Filter beeinflusst wird. Das Verfahren wird gemäß einem Ausführungsbeispiel dadurch realisiert, daß eine rotierende Blende mit radial nach außen zunehmender Blendenöffnung im Strahlengang angebracht wird. Ein erheblicher Vorteil des Verfahrens besteht darin, daß die mechanische Blende ihre Durchlaßcharakteristik zeitlich unbegrenzt beibehält, während Ruß-Gelatine-Filter schnell altern. Die Belichtungszeit wird durch das erfindungsgemäße Verfahren erheblich verkürzt, typischerweise auf weniger als die Hälfte im Vergleich zu einem Verfahren mit Gelatine-Ruß-Filter.The solution to the problem can be found in the first claim. The exposure intensity is changed in that the exposure time varies from place to place and the light intensity is no longer influenced by a filter with a constant exposure time from place to place as was previously the case. According to one embodiment, the method is implemented in that a rotating diaphragm with a diaphragm opening that increases radially outwards is attached in the beam path. A significant advantage of the method is that the mechanical aperture maintains its transmission characteristics indefinitely, while soot-gelatin filters age quickly. The exposure time is shortened considerably by the method according to the invention, typically to less than half compared to a method with a gelatin-soot filter.

Die Verwendung einer rotierenden Blende zur Herstellung der ortsabhängigen Transmission von Gelatine-Ruß-Filtern ist bekannt (DE-OS 20 59 135). Die vorliegende Erfindung zeigt, daß die unmittelbare Anwendung einer solchen Blende für die Belichtung der lichtempfindlichen Leuchtstoffschicht möglich ist und zu erheblicher Verbesserung der Streifenqualität führt.The use of a rotating diaphragm for producing the location-dependent transmission of gelatin-soot filters is known (DE-OS 20 59 135). The present invention shows that the direct use of such an aperture for the exposure of the photosensitive phosphor layer is possible and leads to a considerable improvement in the stripe quality.

Die Erfindung wird im folgenden anhand eines Ausführungsbeispiels unter Verwendung einer rotierenden Blende, wie sie in Figur 2 dargestellt ist, näher beschrieben.The invention is described in more detail below on the basis of an exemplary embodiment using a rotating diaphragm as shown in FIG. 2.

Die Blende B rotiert um den mit M bezeichneten Punkt, welcher auf der Achse des mittigen Belichtungsstrahles liegt. In dem nichtschraffierten Gebiet kann das Licht unbehindert durchstrahlen. Das aus dem schraffiert gezeichneten Blendenmatenal, vorzugsweise einem Stahlblech, ausgeschnittene Gebiet nimmt mit zunehmendem Drehwinkel zu. Dadurch wird beim Rotieren der Blende in der Mitte das Licht im zeitlichen Mittel stark geschwächt, während zunehmend nach außen hin die Lichtstrahlen nur kürzer unterbrochen werden und somit eine größere Lichtmenge während der Belichtungszeit durchtritt. Die Blendenöffnung ist derart gestaltet, daß die, vom Ort abhängige, durchtretende Lichtmenge im zeitlichen Mittel mit derjenigen des üblichen Gelatine-Ruß-Filters übereinstimmt.The aperture B rotates around the point labeled M, which lies on the axis of the central exposure beam. In the unhatched area, the light can shine through unhindered. The area cut out of the hatched aperture material, preferably a steel sheet, increases with increasing angle of rotation. This is when rotating the aperture in the middle greatly weakens the light on average, while the light rays are increasingly only interrupted to the outside for a shorter time and thus a larger amount of light passes through during the exposure time. The aperture is designed in such a way that the amount of light passing through, which is dependent on the location, coincides on average over time with that of the conventional gelatin-soot filter.

Wenn nicht nur eine radialsymmetrische Beeinflussung der Lichtmenge erforderlich ist, so kann natürlich zusätzlich zu der erfindungsgemäßen rotierenden Blende ein schwaches Gelatine-Ruß-Korrekturfilter oder irgend ein anderes Filter bzw. eine Blendenanordnung, verwendet werden. Die Blenden werden mit unterschiedlicher Zeitdauer in verschiedenen Stellen des Strahlengangs eingebracht.If not only a radially symmetrical influence on the amount of light is required, a weak gelatin-soot correction filter or any other filter or an aperture arrangement can of course be used in addition to the rotating aperture according to the invention. The diaphragms are introduced with different times in different places in the beam path.

Die Blende wird in der Belichtungsvorrichtung an der Stelle angebracht, an der bisher das Gelatine-Ruß-Filter angeordnet ist. In Figur 1 säße die erfindungsgemäße Flende also anstelle des Filters 7. Die rotierende Blende ist beispielsweise an ihrem äußersten Umfang in eine drehbare und antreibbare Halterung eingesetzt.The aperture is attached in the exposure device at the point at which the gelatin-soot filter was previously arranged. In Figure 1, the aperture according to the invention would therefore be in place of the filter 7. The rotating aperture is inserted, for example, on its outermost circumference in a rotatable and drivable holder.

Beim Belichten der lichtempfindlichen Schicht des grünen Leuchtstoffs muß bei Verwendung eines Gelatine-Ruß-Filter etwas 20 sec. lang belichtet werden, um Leuchtstoffstreifen gewünschter Breite und Haftfestigkeit zu erzielen. Beim erfindungsgemäßen Verfahren in der Ausführungsform mit rotierender Blende beträgt die Belichtungszeit nur noch 10 sec. Die Drehzahl der Blende ist typischerweise 100 - 200 U/min., d.h. während der 10 sec dreht sich die Blende 17 - 33mal.When the light-sensitive layer of the green phosphor is exposed, a gelatin-soot filter must be used for about 20 seconds in order to obtain phosphor strips of the desired width and adhesive strength. In the method according to the invention in the embodiment with a rotating diaphragm, the exposure time is only 10 seconds. The speed of the diaphragm is typically 100-200 rpm, i.e. during the 10 sec the aperture turns 17 - 33 times.

Claims (3)

1) Verfahren zur Herstellung von Leuchtschirmen für Farbbildröhren mit einem Frontglas und einer Schattenmaske, bei dem eine auf das Frontglas aufgebrachte lichtempfindliche Schicht mittels eines Belichtungsstrahlenbündels durch die Schattenmaske hindurch mit einer von Ort zu Ort auf dem Frontglas variierenden Lichtmenge beleuchtet wird, dadurch gekennzeichnet, daß
die örtliche Änderung der Lichtmenge durch von Ort zu Ort unterschiedliche Belichtungszeiten erzielt wird.
1) Method for producing fluorescent screens for color picture tubes with a front glass and a shadow mask, in which a light-sensitive layer applied to the front glass is illuminated by means of an exposure beam through the shadow mask with a light quantity which varies from place to place on the front glass, characterized in that
the local change in the amount of light is achieved by different exposure times from place to place.
2) Verfahren nach Anspruch 1, dadurch gekennzeichnet, daß die unterschiedlichen Belichtungszeiten mittels Blenden mit unterschiedlichen Verweilzeiten im Belichtungsstrahlenbündel (5) erzeugt werden.2) Method according to claim 1, characterized in that the different exposure times are generated by means of diaphragms with different dwell times in the exposure beam (5). 3) Vorrichtung zur Durchführung des Verfahrens nach Anspruch 2.gekennzeichnet durch eine rotierende Blende (B) mit vom Drehwinkel abhängiger Größe der Blendenöffnung.3) Device for performing the method according to claim 2, characterized by a rotating diaphragm (B) with a size dependent on the angle of rotation of the aperture.
EP80200002A 1979-01-20 1980-01-02 Process for making luminescent screens for colour display tubes and device for carrying out this process Withdrawn EP0017259A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE2902233 1979-01-20
DE19792902233 DE2902233A1 (en) 1979-01-20 1979-01-20 METHOD FOR PRODUCING LUMINAIRE SCREENS FOR COLORED TUBES AND DEVICE FOR IMPLEMENTING THE METHOD

Publications (1)

Publication Number Publication Date
EP0017259A1 true EP0017259A1 (en) 1980-10-15

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Application Number Title Priority Date Filing Date
EP80200002A Withdrawn EP0017259A1 (en) 1979-01-20 1980-01-02 Process for making luminescent screens for colour display tubes and device for carrying out this process

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US (1) US4288512A (en)
EP (1) EP0017259A1 (en)
JP (1) JPS55102154A (en)
DE (1) DE2902233A1 (en)
FI (1) FI800133A7 (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2227361A (en) * 1988-12-23 1990-07-25 Samsung Electronic Devices "Manufacture of colour cathode ray tube screens"
US5010464A (en) * 1988-12-23 1991-04-23 Samsung Electron Devices Co., Ltd. ARC length changing apparatus is exposing device and method thereof

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US10798969B2 (en) 2018-03-16 2020-10-13 R. J. Reynolds Tobacco Company Smoking article with heat transfer component

Citations (4)

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Publication number Priority date Publication date Assignee Title
DE1437152A1 (en) * 1963-12-27 1968-10-31 Sylvania Electric Prod Light damper
DE2221692A1 (en) * 1971-05-05 1972-11-09 Rca Corp Photographic screen printing process for a cathode ray tube
US3841875A (en) * 1972-04-28 1974-10-15 Zenith Radio Corp Method for grading the screen of a color tube
DE2424694A1 (en) * 1973-05-23 1974-12-12 Rca Corp METHOD OF MANUFACTURING A GRADUATED EXPOSURE STENCIL

Family Cites Families (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2717545A (en) * 1951-08-27 1955-09-13 Engeler Walter Illuminating device
US3676129A (en) * 1969-12-01 1972-07-11 Rca Corp Method for making a light intensity correction filter
US4013467A (en) * 1971-06-18 1977-03-22 Matsushita Electronics Corporation Method of manufacturing color picture tubes using rotating light attenuator
US4001018A (en) * 1973-06-13 1977-01-04 Tokyo Shibaura Electric Co., Ltd. Method for making a stripe screen on a face plate of a cathode ray tube by rotating correction lens
JPS5256853A (en) * 1975-11-05 1977-05-10 Hitachi Ltd Manufacture of exposure correction filter
JPS5338967A (en) * 1976-09-21 1978-04-10 Mitsubishi Electric Corp Dimmer filter and its manufacture

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE1437152A1 (en) * 1963-12-27 1968-10-31 Sylvania Electric Prod Light damper
DE2221692A1 (en) * 1971-05-05 1972-11-09 Rca Corp Photographic screen printing process for a cathode ray tube
US3841875A (en) * 1972-04-28 1974-10-15 Zenith Radio Corp Method for grading the screen of a color tube
DE2424694A1 (en) * 1973-05-23 1974-12-12 Rca Corp METHOD OF MANUFACTURING A GRADUATED EXPOSURE STENCIL

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2227361A (en) * 1988-12-23 1990-07-25 Samsung Electronic Devices "Manufacture of colour cathode ray tube screens"
US5010464A (en) * 1988-12-23 1991-04-23 Samsung Electron Devices Co., Ltd. ARC length changing apparatus is exposing device and method thereof
GB2227361B (en) * 1988-12-23 1993-11-17 Samsung Electronic Devices Arc length changing apparatus in exposing device and method thereof

Also Published As

Publication number Publication date
FI800133A7 (en) 1981-01-01
JPS55102154A (en) 1980-08-05
US4288512A (en) 1981-09-08
DE2902233A1 (en) 1980-07-24

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