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US4743799A Expired / Lapsed US ⏱️ 0.0 years remaining

Low pressure arc discharge light source unit

Assignee: Osram Sylvania Inc
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Filing: 1986-11-10
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Granted: 1988-05-10
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Expires: 2006-11-10
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Abstract

Abstract In a low pressure arc discharge light source unit for unipolar or bipolar operation comprising a vacuum-tight glass envelope translucent at at least one side thereof, a rare fill gas and a quantity of mercury therein, a coating of fluorescent phosphor on the inner side of the envelope, and at least two electrodes opposed to each other within the envelope and connected to electrical conductors, the envelope is flat and essentially two-dimensional comprising two planar areas essentially parallel to each other at a small distance. The unit provides for better light output, better radiation efficacy and simpler and less costly manufacture, at the same time being most compact. At least 50% of the radiation of the planar area of the front of the envelope is effective. Means are provided allowing a single cathode to cooperate with a multiplicity of anodes in e.g., a pixel.

Inventors

  • 👤 Helmut M. Loy

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-02 23:22
CPC Classifications
H; H01; H01J; H01J61/00; H01J61/92; H01J61/94; H01J61/02; H01J61/30; H01J61/70; H01J61/72

Claims Analysis

Total Claims: 13
Claim 1
Independent Claim 191 words
A low pressure arc discharge light source unit for unipolar or bipolar operation comprising a vacuum-tight flat essentially two-dimensional glass envelope having two planar areas essentially parallel to each other at a predetermined distance and having two opposing ends, said envelope being translucent at at least one side thereof, a rare fill gas and a quantity of mercury therein, at least three electrodes opposed to each other within the envelope and connected to electrical conductors, at least two parallel separating walls within the envelope located between the planar areas with at least one of the separating walls having a pair of ends with one end thereof extending up to and joining with one of the opposing ends of the envelope and the other end thereof being separated from the other opposing end of the envelope such that at least two discharge spaces are provided with one of the discharge spaces having a multiple arc length, and a fluorescent coating disposed on the inner side of the envelope and including at least two fluorescent phosphors of different spectral power distribution, each of the discharge spaces being coated with a different fluorescent phosphor.
Claim 2
Dependent Claim 191 words
A low pressure arc discharge light source unit for unipolar or bipolar operation comprising a vacuum-tight flat essentially two-dimensional glass envelope having two planar areas essentially parallel to each other at a predetermined distance and having two opposing ends, said envelope being translucent at at least one side thereof, a rare fill gas and a quantity of mercury therein, at least three electrodes opposed to each other within the envelope and connected to electrical conductors, at least two parallel separating walls within the envelope located between the planar areas with at least one of the separating walls having a pair of ends with one end thereof extending up to and joining with one of the opposing ends of the envelope and the other end thereof being separated from the other opposing end of the envelope such that at least two discharge spaces are provided with one of the discharge spaces having a multiple arc length, and a fluorescent coating disposed on the inner side of the envelope and including at least two fluorescent phosphors of different spectral power distribution, each of the discharge spaces being coated with a different fluorescent phosphor.
Claim 3
Dependent Claim 27 words
The light source unit according to claim 1 wherein the envelope comprises two planar bodies of glass being fixed to each other by spacers and glass solder.
Claim 4
Dependent Claim 44 words
The light source unit according to claim 1 wherein the envelope comprises a planar glass body and a trough-shaped glass body having a planar area and a rim, both bodies bonded to each other along the rim of the trough-shaped body by glass solder.
Claim 5
Dependent Claim 31 words
The light source unit according to claim 1 wherein the envelope comprises two trough-shaped glass bodies having planar areas and rims, both bodies bonded together along their rims by glass solder.
Claim 6
Dependent Claim 47 words
The light source unit according to claims 1, 2, 3 or 4 wherein there is a distance of approximately 3 mm to 10 mm between planar bodies or a planar body and the planar area of a trough-shaped body or the planar areas of two trough-shaped bodies.
Claim 7
Dependent Claim 44 words
The light source unit according to claim 1 wherein on at least one of the inner sides of the planar areas there is a fluorescent phosphor coating whereas on the inner or outer side of the opposite planar area there is a reflective coating.
Claim 8
Dependent Claim 33 words
The light source unit according to claim 1 wherein at least one separating wall within the envelope extends at both ends up to and sealingly joins with the opposing ends of the envelope.
Claim 9
Dependent Claim 61 words
The light source unit according to claim 1 wherein each of the discharge spaces is formed by walls extending up to and joining with an opposing end of the envelope with only one end thereof whereas the other end keeps a distance from the other opposinge end, a common cathode is arranged within said distance serving each of the discharge spaces.
Claim 10
Dependent Claim 20 words
The light source unit according to claim 1 for unipolar operation wherein a recessed space for the cathode is provided.
Claim 11
Dependent Claim 28 words
The light source unit according to claim 1 wherein for unipolar operation the anode of each discharge space is a plate or a conductive coating inside the envelope.
Claim 12
Dependent Claim 45 words
The light source unit of claim 1 wherein a plurality of discharge spaces having a multiple arc length is provided, at least one of said discharge spaces having a multiple arc length being different from the multiple arc lengths of the other discharge spaces present.
Claim 13
Dependent Claim 58 words
The light source unit of claim 1 wherein all the discharge spaces are formed by walls having one end extending up to and joining with an opposing end of the envelope, the other end keeps a distance from the other of the opposing ends, one common cathode is arranged within said distance serving all the discharge spaces present.

References Cited (Backward Citations)

US3508103A Cited
US3551736A Cited
DE2952535A1 Cited
JPS5661756A Cited
JPS57180067A Cited
JPS59127357A Cited
FR2549640A1 Cited
US4594527A Cited
US4665341A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1991-05-10 1991-11-09 1992-05-10 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1995-05-10 1995-11-09 1996-05-10 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1999-05-10 1999-11-09 2000-05-10 $7700.00 Window Closed / Lapsed

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