Display apparatus

• US 20010019240A1
• Filed: 12/06/2000
• Published: 09/06/2001
• Est. Priority Date: 12/09/1999
• Status: Active Grant

• Current Assignee: Fujifilm Corporation (Fujifilm Holdings Corporation)
• Original Assignee: Fuji Photo Film Co Limited (Fujifilm Holdings Corporation)
• Inventors: Takahashi, Kenji
• Granted Patent: US 6,717,348 B2
• Time in Patent Office: Days
• US Class Current: 313/483
• CPC Class Codes: G02F 1/133617 Illumination with ultraviolet light; Luminescent elements or materials associated to the cell
• CPC Class Codes: H01J 29/187 screens with more than one luminescent material (as mixtures for the treatment of the screens) for several superimposed luminescent layers H01J29/26; for adjacent dots or lines of different luminescent material H01J29/32
• CPC Class Codes: H01J 29/20 characterised by the luminescent material
• CPC Class Codes: H01J 29/327 Black matrix materials
• CPC Class Codes: H01J 63/06 Lamps with luminescent screen excited by the ray or stream

Abstract

A display apparatus has a light source unit for generating excitation light, an optical element for modulating the excitation light generated by the light source unit for each of pixels in a two-dimensional plane, and a fluorescent screen for receiving the excitation light modulated by the optical element at a first surface and emitting visible light from a second surface opposite to the first surface. The fluorescent screen includes a layer of phosphor having an absorption coefficient of 1×10² cm⁻¹ or more for the excitation light.

Claims

1. A display apparatus comprising:

a light source unit for generating excitation light having a predetermined wavelength;

an optical element for modulating the excitation light generated by the light source unit for each of pixels in a two-dimensional plane; and

a fluorescent screen for receiving the excitation light modulated by the optical element at a first surface and emitting visible light from a second surface opposite to the first surface, said fluorescent screen including a layer of phosphor having an absorption coefficient not smaller than 1×

10² cm<sup>−

1</sup>for the excitation light.

7. A display apparatus according to

claim 1

, wherein a thickness of said layer of phosphor is not larger than 120 μ

m.

15. A display apparatus according to

claim 1

, wherein said phosphor includes at least one of ZnO:

Zn;

(Sr, Ca, Ba)₅(PO₄)₃Cl;

Eu;

ZnS;

Ag, Al;

ZnS;

Au, Ag, Al;

ZnS;

Cu, Au, Al;

(Zn, Cd)S;

Ag;

(Zn, Cd)S;

Cu;

Y₂O₃;

Bi, Eu;

LiEuW₂O₈;

Ca₈Mg (SiO₄) ₄Cl₂;

Eu, Mn;

Ba₂ZnS₃;

Mn;

Y₂O₂S;

Eu;

BaMg₂Al₁₆O₂₇;

Eu;

BaMg₂Al₁₆0₂₇;

Eu, Mn;

BaMgAl₁₀O₁₇;

Eu;

BaMgAl₁₀O₁₇;

Eu, Mn;

Sr₅ (PO₄) ₃Cl;

Eu;

(Sr, Ba) SiO₄;

Eu;

SrGa₂S₄;

Eu;

K₅Eu_2.5 (WO₄) 6.75;

ZnS;

Cu, Al; and

3.5MgO·

0.5MgF₂ ·

GeO₂;

Mn.

17. A display apparatus according to

claim 1

, wherein the fluorescent screen further includes second phosphor which is different from said phosphor and generates visible light upon receiving luminescent light from said phosphor.

19. A display apparatus according to

claim 17

, wherein said second phosphor includes at least one of Y₃Al₅O₁₂:

Ce and Y₃(Al, Ga)₅O₁₂;

Ce.

2. A display apparatus comprising:

a light source unit for generating excitation light having a predetermined wavelength;

an optical element for modulating the excitation light generated by the light source unit for each of pixels in a two-dimensional plane; and

a fluorescent screen for receiving the excitation light modulated by the optical element at a first surface and emitting visible light from a second surface opposite to the first surface, said fluorescent screen including a layer of phosphor in which a thickness of said layer of phosphor that gives a maximum brightness caused by the excitation light is not larger than 120 μ

m.

11. A display apparatus according to

claim 2

, wherein the thickness of said layer of phosphor that gives a maximum brightness caused by the excitation light is not larger than 80 μ

m.

3. A display apparatus comprising:

a light source unit for generating excitation light having a predetermined wavelength;

an optical element for modulating the excitation light generated by the light source unit for each of pixels in a two-dimensional plane; and

a fluorescent screen for receiving the excitation light modulated by the optical element at a first surface and emitting visible light from a second surface opposite to the first surface, said fluorescent screen including a layer of phosphor in which a product of an absorption coefficient for the excitation light and a thickness of said layer of phosphor is within a range from 1 to 8.

8. A display apparatus according to

claim 3

, wherein the thickness of said layer of phosphor is not larger than 120 μ

m.

13. A display apparatus according to

claim 3

, wherein the product of the absorption coefficient and the thickness of said layer of phosphor is within a range from 2 to 4.

4. A display apparatus comprising:

a light source unit for generating excitation light having a predetermined wavelength;

an optical element for modulating the excitation light generated by the light source unit for each of pixels in a two-dimensional plane;

a projection lens to project the excitation light modulated by the optical element; and

a fluorescent screen for receiving the excitation light projected by the projection lens at a first surface and emitting visible light from a second surface opposite to the first surface, said fluorescent screen including a layer of phosphor having an absorption coefficient not smaller than 1×

10² cm<sup>−

1</sup> for the excitation light.

9. A display apparatus according to

claim 4

, wherein a thickness of said layer of phosphor is not larger than 120 μ

m.

18. A display apparatus according to

claim 4

, wherein the fluorescent screen further includes second phosphor which is different from said phosphor and generates visible light upon receiving luminescent light from said phosphor.

20. A display apparatus according to

claim 18

, wherein said second phosphor includes at least one of Y₃Al₅O₁₂:

Ce and Y₃(Al, Ga)₅O₁₂;

Ce.

5. A display apparatus comprising:

a light source unit for generating excitation light having a predetermined wavelength;

an optical element for modulating the excitation light generated by the light source unit for each of pixels in a two-dimensional plane;

a projection lens to project the excitation light modulated by the optical element; and

a fluorescent screen for receiving the excitation light projected by the projection lens at a first surface and emitting visible light from a second surface opposite to the first surface, said fluorescent screen including a layer of phosphor in which a thickness of said layer of phosphor that gives a maximum brightness caused by the excitation light is not larger than 120 μ

m.

12. A display apparatus according to

claim 5

, wherein the thickness of said layer of phosphor that gives a maximum brightness caused by the excitation light is not larger than 80 μ

m.

6. A display apparatus comprising:

a light source unit for generating excitation light having a predetermined wavelength;

an optical element for modulating the excitation light generated by the light source unit for each of pixels in a two-dimensional plane;

a projection lens to project the excitation light modulated by the optical element; and

a fluorescent screen for receiving the excitation light projected by the projection lens at a first surface and emitting visible light from a second surface opposite to the first surface, said fluorescent screen including a layer of phosphor in which a product of an absorption coefficient for the excitation light and a thickness of said layer of phosphor is within a range from 1 to 8.

10. A display apparatus according to

claim 6

, wherein the thickness of said layer of phosphor is not larger than 120 μ

m.

14. A display apparatus according to

claim 6

, wherein the product of the absorption coefficient and the thickness of said layer of phosphor is within a range from 2 to 4.

16. A display apparatus according to

claim 6

, wherein the phosphor includes at least one of ZnO:

Zn;

(Sr, Ca, Ba)₅(PO₄)₃Cl;

Eu;

ZnS;

Ag, Al;

ZnS;

Au, Ag, Al;

ZnS;

Cu, Au, Al;

(Zn, Cd)S;

Ag;

(Zn, Cd)S;

Cu;

Y₂O₃;

Bi, Eu;

LiEuW₂O₈;

Ca₈Mg (SiO₄) ₄Cl₂;

Eu, Mn;

Ba₂ZnS₃;

Mn;

Y₂O₂S;

Eu;

BaMg₂Al₁₆O₂₇;

Eu;

BaMg₂Al₁₆O₂₇;

Eu, Mn;

BaMgAl₁₀O₁₇;

Eu;

BaMgAl₁₀O₁₇;

Eu, Mn;

Sr₅(PO₄) ₃Cl;

Eu;

(Sr, Ba) SiO₄;

Eu;

SrGa₂S₄;

Eu;

K₅Eu₂.₅ (WO₄) 6.75;

ZnS;

Cu, Al; and

3.5MgO·

0.5MgF₂ GeO₂;

Mn.