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US5209690A Expired / Lapsed US ⏱️ 0.0 years remaining

Method of vapor depositing an interference filter layer on the inside of a display window, a display window, a projection cathode ray tube and a projection television apparatus

Assignee: US Philips Corp
•
Filing: 1992-07-20
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Granted: 1993-05-11
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Expires: 2012-07-20
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Abstract

Abstract Method of vapor-depositing an interference filter layer on the inside of a display window, a display window, a projection cathode ray tube and a projection television apparatus. A method of manufacturing a projection cathode ray tube comprising an interference filter on an inwardly directed surface of a display window, the method comprising as a process step the vapor deposition of at least one layer of the interference filter. It has been found that the edges of a display window during the vapor deposition of an interference filter layer detrimentally influence the thickness of the vapor deposited layer, the thickness increases more towards the edges than follows from geometrical computations. In the method according to the invention vapor deposition is performed on a display window for which the height of the edge is less than 1/5 of the minor axis. The display screen preferably comprises a recessive edge.

Inventors

  • 👤 Leendert Vriens
  • 👤 Andre Van der Voort
  • 👤 Antonius P. van de Langenberg

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-07 09:45
CPC Classifications
H; H01; H01J; H01J29/00; H01J29/86; H01J29/89; H01J29/02; H01J29/10; H01J29/18; H01J29/185; H01J29/24; H01J29/28; H01J9/00; H01J9/20; H01J2229/00; H01J2229/89; H01J2229/8907; H01J2229/8913; H01J2229/8916; H01J2229/8918

Claims Analysis

Total Claims: 16
Claim 1
Independent Claim 68 words
A method of manufacturing a projection cathode ray tube comprising a display window, the method comprising vapour depositing a multilayer interference filter on an inside surface of the display window, characterized by surrounding the display window with an edge having a height above the inside surface which is from about 1/10 to about 1/5 of the minimum distance between the centre and the edge of the display window.
Claim 2
Independent Claim 68 words
A method of manufacturing a projection cathode ray tube comprising a display window, the method comprising vapour depositing a multilayer interference filter on an inside surface of the display window, characterized by surrounding the display window with an edge having a height above the inside surface which is from about 1/10 to about 1/5 of the minimum distance between the centre and the edge of the display window.
Claim 3
Dependent Claim 23 words
A method as claimed in claim 1, characterized in that the side of the display window facing the vapour deposition source is curved.
Claim 4
Dependent Claim 26 words
A method as claimed in claim 1, characterized in that vapour deposition is carried out with a background gas pressure of more than 2*10 -4 mbar.
Claim 5
Dependent Claim 15 words
A method as claimed in claim 1, characterized in that TiO 2 is vapour deposited.
Claim 6
Dependent Claim 19 words
A method as claimed in claim 1, characterized in that a short wave pass interference filter is vapour deposited.
Claim 7
Dependent Claim 88 words
A method as claimed in claim 5, characterized in that a short wave pass filter is vapour-deposited which comprises a stack of at least six layers having alternately a high and a low refractive index, each layer having an optical thickness between 0.2 λ f and 0.3 λ f , an average optical thickness of 0.25 λ f , λ f being equal to pxλ and λ being a central wavelength selected from the emission spectrum of the display screen, p being a number between 1.18 and 1.33.
Claim 8
Dependent Claim 17 words
A method as claimed in claim 1, characterized in that a bandpass interference filter is vapour deposited.
Claim 9
Independent Claim 40 words
A method of manufacturing a projection cathode ray tube comprising a display window, the method comprising vapour depositing a multilayer interference filter on an inside surface of the display window, characterized in that the display window comprises a recessive edge.
Claim 10
Independent Claim 40 words
A method of manufacturing a projection cathode ray tube comprising a display window, the method comprising vapour depositing a multilayer interference filter on an inside surface of the display window, characterized in that the display window comprises a recessive edge.
Claim 11
Dependent Claim 23 words
A method as claimed in claim 8, characterized in that the side of the display window facing the vapour deposition source is curved.
Claim 12
Dependent Claim 26 words
A method as claimed in claim 8, characterized in that vapour deposition is carried out with a background gas pressure of more than 2*10 -4 mbar.
Claim 13
Dependent Claim 15 words
A method as claimed in claim 8, characterized in that TiO 2 is vapour deposited.
Claim 14
Dependent Claim 17 words
A method as claimed in claim 8, characterized in that a bandpass interference filter is vapour deposited.
Claim 15
Dependent Claim 19 words
A method as claimed in claim 8, characterized in that a short wave pass interference filter is vapour deposited.
Claim 16
Dependent Claim 87 words
A method as claimed in claim 13, characterized in that a short wave pass filter is vapour-deposited which comprises a stack of at least six layers having alternately a high and low refractive index, each layer having an optical thickness between 0.2 λ f and 0.3 λ f , an average optical thickness of 0.25 λ f , λ f being equal to pxλ and λ being a central wavelength selected from the emission spectrum of the display screen, p being a number between 1.18 and 1.33.

References Cited (Backward Citations)

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USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1996-05-10 1996-11-09 1997-05-11 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2000-05-10 2000-11-09 2001-05-11 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2004-05-10 2004-11-09 2005-05-11 $7700.00 Window Closed / Lapsed

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