Green-emitting phosphor and cathode-ray tube employing it

• US 5,600,202 A
• Filed: 08/30/1995
• Issued: 02/04/1997
• Est. Priority Date: 03/03/1994
• Status: Expired due to Fees

• Current Assignee: Hitachi, Ltd., Kasei Optonix, Ltd. (Mitsubishi Chemical Group Corp.)
• Original Assignee: Hitachi, Ltd., Kasei Optonix, Ltd. (Mitsubishi Chemical Group Corp.)
• Inventors: Yamada, Tsutomu, Hase, Takashi, Uehara, Yasuhiko, Oguri, Yasuo, Toyama, Hisashi
• Primary Examiner(s): O'Shea, Sandra L.
• Assistant Examiner(s): NING, JOHN K
• Application Number:
  US08/521,492
• Time in Patent Office: 524 Days
• Field of Search: 313/467, 313/486, 313/487, 313/468, 313/488, 252/301.4 R
• US Class Current: 313/467
• CPC Class Codes: C09K 11/7767 Chalcogenides
• CPC Class Codes: C09K 11/7774 Aluminates
• CPC Class Codes: H01J 29/20 characterised by the luminescent material

Abstract

A green-emitting phosphor of Tb-activated oxide, which is represented by the compositional formula:

(Y.sub.l-x-y-z Tb.sub.x Yb.sub.yD.sub.z).sub.3 (Al.sub.l-w Ga.sub.w).sub.5

O₁₂

wherein D is at least one element selected from the group consisting of Sc and La, and x, y, z and w are numbers satisfying the following conditions:

1×10.sup.-2 ≦x≦2×10.sup.-1

1×10.sup.-6 ≦y≦2×10.sup.-2

1×10.sup.-4 ≦z≦5×10.sup.-1

0≦w≦1,

and which contains from 1×10^-5 to 1×10^-2 gram atom of barium element per mol of the phosphor and is capable of emitting a color within the following range by CIE chromaticity coordinates:

0.325≦X≦0.360

0.540≦Y≦0.625.

Claims

1. A green-emitting phosphor of Tb-activated oxide, which is represented by the compositional formula:

space="preserve" listing-type="equation">(Y.sub.1-x-y-z Tb.sub.x Yb.sub.y D.sub.z).sub.3 (Al.sub.1-w Ga.sub.w).sub.5 O.sub.12

wherein D is at least one element selected from the group consisting of Sc and La, and x, y, z and w are numbers satisfying the following conditions;

space="preserve" listing-type="equation">1×

10.sup.-2 ≦

x≦

2×

10.sup.-1

space="preserve" listing-type="equation">1×

10.sup.-6 ≦

y≦

2×

10.sup.-2

space="preserve" listing-type="equation">1×

10.sup.-4 ≦

z≦

5×

10.sup.-1

space="preserve" listing-type="equation">0≦

w≦

1,

and which contains from 1×

10^-5 to 1×

10^-2 gram atom of barium element per mol of the phosphor and is capable of emitting a color within the following range by CIE chromaticity coordinates;

space="preserve" listing-type="equation">0.325≦

X≦

0.360

space="preserve" listing-type="equation">0.540≦

Y≦

0.625.

5. A cathode-ray tube comprising a faceplate, a fluorescent layer of a green-emitting phosphor formed on the inner surface of the faceplate, an electron gun for emitting an electron beam to the fluorescent layer to excite the green-emitting phosphor for emission, and a control means for scanning the electron beam emitted from the electron gun, wherein the green-emitting phosphor is as defined in claim 1.

2. A green-emitting phosphor of Tb-activated oxide, which is represented by the compositional formula:

space="preserve" listing-type="equation">(Y.sub.1-x-y-z Tb.sub.x Sm.sub.y D.sub.z).sub.3 (Al.sub.1-w Ga.sub.w).sub.5 O.sub.12

wherein D is at least one element selected from the group consisting of Sc and La, and x, y, z and w are numbers satisfying the following conditions;

space="preserve" listing-type="equation">1×

10.sup.-2 ≦

x≦

2×

10.sup.-1

space="preserve" listing-type="equation">1×

10.sup.-6 ≦

y≦

2×

10.sup.-3

space="preserve" listing-type="equation">1×

10.sup.-4 ≦

z≦

5×

10.sup.-1

space="preserve" listing-type="equation">0≦

w≦

1,

and which contains from 1×

10^-5 to 1×

10^-2 gram atom of barium element per mol of the phosphor and is capable of emitting a color within the following range by CIE chromaticity coordinates;

6. A cathode-ray tube comprising a faceplate, a fluorescent layer of a green-emitting phosphor formed on the inner surface of the faceplate, an electron gun for emitting an electron beam to the fluorescent layer to excite the green-emitting phosphor for emission, and a control means for scanning the electron beam emitted from the electron gun, wherein the green-emitting phosphor is as defined in claim 2.

3. 325≦

X≦

0.360

space="preserve" listing-type="equation">0.540≦

Y≦

0.625.

7. A cathode-ray tube comprising a faceplate, a fluorescent layer of a green-emitting phosphor formed on the inner surface of the faceplate, an electron gun for emitting an electron beam to the fluorescent layer to excite the green-emitting phosphor for emission, and a control means for scanning the electron beam emitted from the electron gun, wherein the green-emitting phosphor is as defined in claim 3.

4. A green-emitting phosphor of Tb-activated oxide, which is represented by the compositional formula:

(Y_1-x-y-z Tb_x Eu_y D_z)₃ (Al_1-w Ga_w)₅ O₁₂

wherein D is at least one element selected from the group consisting of Sc and La, and x, y, z and w are numbers satisfying the following conditions;

space="preserve" listing-type="equation">1×

10.sup.-2 ≦

x≦

2×

10.sup.-1

space="preserve" listing-type="equation">1×

10.sup.-6 ≦

y≦

3×

10.sup.-4

space="preserve" listing-type="equation">1×

10.sup.-4 ≦

z≦

5×

10.sup.-1

space="preserve" listing-type="equation">0≦

w≦

1,

and which contains from 1×

10^-5 to 1×

10^-2 gram atom of barium element per mol of the phosphor and is capable of emitting a color within the following range by CIE chromaticity coordinates;

space="preserve" listing-type="equation">0.325≦

X≦

0.360

space="preserve" listing-type="equation">0.540≦

Y≦

0.625.