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US4617490A Expired / Lapsed US ⏱️ 0.0 years remaining

Cathode ray tube device with improved color filtering system

Assignee: Philips North America LLC
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Filing: 1984-12-07
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Granted: 1986-10-14
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Expires: 2004-12-07
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Abstract

Abstract Halos occurring around bright light spots generated by cathode ray tube devices in which the light emitted by the tubes is filtered by filtering solutions are significantly reduced by the addition of cinnamic alcohol and/or cinnamaldehyde to the solution.

Inventors

  • 👤 Brian J. Fitzpatrick
  • 👤 Phyllis M. Harnack

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-04 13:32
CPC Classifications
H; H01; H01J; H01J29/00; H01J29/86; H01J29/89; H01J2229/00; H01J2229/89; H01J2229/8907

Claims Analysis

Total Claims: 12
Claim 1
Independent Claim 172 words
A cathode-ray tube device for generating a bright light spot comprising: a cathode-ray tube including an evacuated envelope, means located within said envelope to generate an electron beam, a phosphor capable of emitting visible light radiation when excited by electrons, positioned within said envelope and in the path of said electron beam, and a transparent face plate forming part of said envelope and situated in the path of said visible light radiation and, positioned outside of the outer surface of said face plate and in the path of said visible light radiation, a light beam filtering means comprising, in a container which at least in the path of said light radiation, is transparent to said radiation and which comprises as a visible light radiation exit member a glass end plate, a light filtering solution containing in addition to light filtering ingredients, as index of refraction raising ingredients, a compound selected from the group consisting of cinnamic alcohol and cinnamaldehyde and mixtures thereof in an amount sufficient to form a concentrated solution thereof.
Claim 2
Dependent Claim 172 words
A cathode-ray tube device for generating a bright light spot comprising: a cathode-ray tube including an evacuated envelope, means located within said envelope to generate an electron beam, a phosphor capable of emitting visible light radiation when excited by electrons, positioned within said envelope and in the path of said electron beam, and a transparent face plate forming part of said envelope and situated in the path of said visible light radiation and, positioned outside of the outer surface of said face plate and in the path of said visible light radiation, a light beam filtering means comprising, in a container which at least in the path of said light radiation, is transparent to said radiation and which comprises as a visible light radiation exit member a glass end plate, a light filtering solution containing in addition to light filtering ingredients, as index of refraction raising ingredients, a compound selected from the group consisting of cinnamic alcohol and cinnamaldehyde and mixtures thereof in an amount sufficient to form a concentrated solution thereof.
Claim 3
Dependent Claim 37 words
The cathode ray tube device of claim 1, wherein a solvent of the solution is a mixture of water and an alcohol selected from the group consisting of 1,2-ethylene glycol, 1,2-propanediol, glycerol, ethanol, propanol, isopropanol and methanol.
Claim 4
Dependent Claim 58 words
The cathode ray tube device of claim 2 wherein the visible light radiation is green light radiation, the bright light spot is a bright green light spot, the phosphor is a terbium activated phosphor capable of emitting visible green radiation when excited by electrons and the light filtering solution contains as a light filtering ingredient a praseodymium salt.
Claim 5
Dependent Claim 25 words
The cathode ray tube device of claim 3 wherein the solvent is a mixture of water of up to 80% by weight of ethylene glycol.
Claim 6
Dependent Claim 32 words
The cathode ray tube device of claim 4 wherein in addition to the praseodymium salt, sodium fluorescein and Fast Green FCF are present in the light filtering solution as light filtering ingredients.
Claim 7
Dependent Claim 24 words
The cathode ray tube device of claim 4 wherein the light beam filtering means is sealed to the outer surface of the face plate.
Claim 8
Dependent Claim 24 words
The cathode ray tube device of claim 5 wherein the light beam filtering means is sealed to the outer surface of the face plate.
Claim 9
Dependent Claim 45 words
The cathode ray tube device of claim 2 wherein the visible light radiation is blue light radiation, the phosphor is a silver activated zinc sulfide phosphor and a soluble erbium salt and methyl violet are present in the light filtering solution as light filtering ingredients.
Claim 10
Dependent Claim 24 words
The cathode ray tube device of claim 8 wherein the light beam filtering means is sealed to the outer surface of the face plate.
Claim 11
Dependent Claim 43 words
The cathode ray tube device of claim 2 wherein the visible light radiation is red light radiation, the phosphor is an erbium activated phosphor and a holmium salt and a neodymium salt are present in the light filtering solution as light filtering ingredients.
Claim 12
Dependent Claim 23 words
The cathode ray tube device of claim 10 wherein the light beam filtering means is sealed to the outer surface of the face.

References Cited (Backward Citations)

US4529905A Cited
GB2098393A Cited
US4538089A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1989-10-13 1990-04-14 1990-10-14 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1993-10-13 1994-04-14 1994-10-14 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1997-10-13 1998-04-14 1998-10-14 $7700.00 Window Closed / Lapsed

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