EP0042149A1
Expired / Lapsed
EP
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Radiation excited phosphor screen and method for manufacturing the same
Assignee: Toshiba Corp
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Filing: 1981-06-11
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Granted: —
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Expires: 2001-06-11
Abstract
Abstract An input phosphor screen includes a substrate (10) having a substantially smooth surface, and first and second phosphor layers (12, 14) both vapor-deposited sequentially on the substrate. The first layer (12) is made of phosphor crystal particles (11) having a mean diameter of 15 µm or less. The second layer (14) has a thickness ten or more times that of the first layer (12) and is made of individual columnar crystals (13) of alkali halide grown vertically on the crystal particles (11), standing close together with fine spaces (15) therebetween. A third layer (16) is preferably deposited on the second layer (14) as a continuous film. These three layers (12, 14, 16) can be deposited by evaporating a phosphor material or materials at a prescribed temperature and at a predetermined degree of vacuum.
Inventors
- 👤 Takashi Noji
- 👤 Norio Harao
- 👤 Yoshiharu Obata
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-03 08:59
CPC Classifications
H; H01; H01J; H01J29/00; H01J29/02; H01J29/10; H01J29/36; H01J29/38; H01J29/385; G; G21; G21K; G21K4/00
Claims Analysis
Total Claims: 22
Claim 1
Independent Claim
98 words
A radiation excited input phosphor screen comprising: a substrate having a substantially smooth surface; a first phosphor layer vapor-deposited on said smooth surface of-said substrate and including phosphor crystal particles having mean diameter of 15 µm or less; and a second phosphor layer of alkali halide phosphor material vapor-deposited on said first phosphor layer and including individual columnar crystals grown substantially vertically with respect to said smooth surface of said substrate, said columnar crystals standing close together with fine spaces therebetween, said second phosphor layer having a thickness ten or more times that of said first phosphor layer.
Claim 2
Dependent Claim
98 words
A radiation excited input phosphor screen comprising: a substrate having a substantially smooth surface; a first phosphor layer vapor-deposited on said smooth surface of-said substrate and including phosphor crystal particles having mean diameter of 15 µm or less; and a second phosphor layer of alkali halide phosphor material vapor-deposited on said first phosphor layer and including individual columnar crystals grown substantially vertically with respect to said smooth surface of said substrate, said columnar crystals standing close together with fine spaces therebetween, said second phosphor layer having a thickness ten or more times that of said first phosphor layer.
Claim 3
Dependent Claim
28 words
A phosphor screen according to claim 1, wherein said first phosphor layer and said second phosphor layer are made of the same kind of alkali halide phosphor material.
Claim 4
Dependent Claim
16 words
A phosphor screen according to claim 2, wherein said alkali halide phosphor material is cesium halide.
Claim 5
Dependent Claim
23 words
A phosphor screen according to claim 3, wherein the total thickness of said first and second phosphor layers is 100 to 400 µm.
Claim 6
Dependent Claim
55 words
A phosphor screen according any one of claims 1 to 4, further comprising a third phosphor layer which is vapor-deposited to a thickness of 30 µm or less on said second phosphor layer in such a manner as to be continuous and to seal said fine spaces between said columnar crystals at the tops thereof.
Claim 7
Dependent Claim
20 words
A phosphor screen according to claim 5, wherein said third phosphor layer is made of an alkali halide phosphor material.
Claim 8
Dependent Claim
16 words
A phosphor screen according to claim 6, wherein said alkali halide phosphor material is cesium iodide.
Claim 9
Dependent Claim
29 words
A phoshor screen according to claim 7, further comprising a transparent conductive layer vapor deposited 0 on said third phosphor layer to a thickness of 5,000 A or less.
Claim 10
Dependent Claim
17 words
A phosphor screen according to claim 8, wherein said transparent conductive layer is made of indium oxide.
Claim 11
Dependent Claim
31 words
A phosphor screen according to claim 9, further comprising a protective layer vapor-deposited between said third phosphor layer and said transparent conductive layer to a thickness of 200 to 1,000 A.
Claim 12
Dependent Claim
16 words
A phosphor screen according to claim 10, wherein said protective layer is made of aluminum oxide.
Claim 13
Dependent Claim
16 words
A phosphor screen according to claim 11, further comprising a photoemissive layer on said conductive layer.
Claim 14
Independent Claim
148 words
A method for manufacturing a radiation excited input phosphor screen comprising: maintaining a substrate with a substantially smooth surface at a temperature of 20 to 150°C; evaporating a phosphor material in an atmosphere held at a degree of vacuum of 1 x 10 -3 to 1 x 10 -2 Torr to deposit a first phosphor layer including phosphor crystal particles having a mean diameter of 15 µm or less on said smooth surface of said substrate; and evaporating an alkali halide phosphor material in an atmosphere held at a degree of vacuum of 1 x 10 -4 to 1 x 10-2 Torr to deposit on said crystal particles of said first phosphor layer a second phosphor layer including columnar crystals grown to a thickness which is 10 or more times that of said first phosphor layer, with fine spaces extending therebetween to the tops of said columnar crystals.
Claim 15
Independent Claim
148 words
A method for manufacturing a radiation excited input phosphor screen comprising: maintaining a substrate with a substantially smooth surface at a temperature of 20 to 150°C; evaporating a phosphor material in an atmosphere held at a degree of vacuum of 1 x 10 -3 to 1 x 10 -2 Torr to deposit a first phosphor layer including phosphor crystal particles having a mean diameter of 15 µm or less on said smooth surface of said substrate; and evaporating an alkali halide phosphor material in an atmosphere held at a degree of vacuum of 1 x 10 -4 to 1 x 10-2 Torr to deposit on said crystal particles of said first phosphor layer a second phosphor layer including columnar crystals grown to a thickness which is 10 or more times that of said first phosphor layer, with fine spaces extending therebetween to the tops of said columnar crystals.
Claim 16
Dependent Claim
30 words
A method according to claim 13, wherein said atmosphere for vapor deposition is free from moisture and contains at least one gas which does not chemically react with phosphor vapor.
Claim 17
Dependent Claim
25 words
A method according to claim 14, wherein said first phosphor layer and said second phosphor layer are made of the same alkali halide phosphor material.
Claim 18
Dependent Claim
15 words
A method according to claim 15, wherein said alkali halide phosphor material is cesium iodide.
Claim 19
Independent Claim
68 words
A method according to any one of claims 13 to 16, further comprising evaporating a phosphor material in an atmosphere held at a degree of vacuum of 1 x 10 -5 Torr or less to deposit on said second phosphor layer a continuous third phosphor layer having a thickness of 30 µm or less in such a manner as to seal said fine spaces between said columnar crystals.
Claim 20
Dependent Claim
18 words
A method according to claim 17, wherein said third layer is formed of an alkali halide phosphor material.
Claim 21
Dependent Claim
15 words
A method according to claim 18, wherein said alkali halide phosphor material is cesium iodide.
Claim 22
Dependent Claim
16 words
An image tube having a phosphor screen according to any one of claims 1 to 12.
References Cited (Backward Citations)
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