Phosphor substrate, display device, and electronic apparatus

• US 9,182,631 B2
• Filed: 08/03/2012
• Issued: 11/10/2015
• Est. Priority Date: 08/05/2011
• Status: Active Grant

• Current Assignee: Sharp Kabushiki Kaisha (Hon Hai Precision Industry Co., Ltd.)
• Original Assignee: Sharp Kabushiki Kaisha (Hon Hai Precision Industry Co., Ltd.)
• Inventors: BESSHO, Hisanori, Shibata, Satoshi, Iwata, Akiko, Koden, Mitsuhiro, Kobayashi, Yuhki
• Primary Examiner(s): Santiago, Mariceli
• Assistant Examiner(s): Lee, Brenitra M
• Application Number:
  US14/236,896
• Publication Number:
  US 20140168572A1
• Time in Patent Office: 1,194 Days
• Field of Search: 313498-512
• US Class Current: 1/1
• CPC Class Codes: F21K 9/64 using wavelength conversion means distinct or spaced from the light-generating element, e.g. a remote phosphor layer
• CPC Class Codes: G02F 1/133614 using photoluminescence, e.g. phosphors illuminated by UV or blue light
• CPC Class Codes: G02F 1/133617 Illumination with ultraviolet light; Luminescent elements or materials associated to the cell
• CPC Class Codes: G02F 1/133621 providing coloured light G02F1/133617, G02F1/133533 take precedence
• CPC Class Codes: H05B 33/10 Apparatus or processes specially adapted to the manufacture of electroluminescent light sources
• CPC Class Codes: H05B 33/14 characterised by the chemical or physical composition or the arrangement of the electroluminescent material , or by the simultaneous addition of the electroluminescent material in or onto the light source
• CPC Class Codes: H10K 50/854 comprising scattering means
• CPC Class Codes: H10K 50/865 comprising light absorbing layers, e.g. light-blocking layers
• CPC Class Codes: H10K 59/877 comprising scattering means
• CPC Class Codes: H10K 59/8792 comprising light absorbing layers, e.g. black layers

Abstract

A phosphor substrate (10) includes a substrate (1), phosphor layers (3R, 3G, and 3B) which are disposed on the substrate (1) and which emit fluorescences (L2) using incident excitation light (L1), and a partition (7) surrounding side faces of the phosphor layers (3R, 3G, and 3B), in which at least portions of the partition (7) in contact with the phosphor layers (3R, 3G, and 3B) have light-scattering properties.

Claims

1. A phosphor substrate comprising:

a substrate;

a phosphor layer disposed on the substrate, the phosphor layer emitting fluorescence using incident excitation light; and

a partition surrounding a side face of the phosphor layer,

wherein at least a portion of the partition in contact with the phosphor layer has light-scattering properties, is white, and is composed of a material containing a resin and light-scattering particles, the resin having a first refractive index, the light scattering particles having a second refractive index, the second refractive index being higher than the first refractive index, the light scattering particles being dispersed in the resin, each of the light scattering particles having a particle size of 100 nm to 500 nm.

2. The phosphor substrate according to claim 1, wherein at least the portion of the partition in contact with the phosphor layer has an uneven shape.

3. A display device comprising the phosphor substrate according to claim 1 and a light source configured to emit excitation light with which the phosphor layer is irradiated.

4. The display device according to claim 3,

wherein the phosphor substrate includes a plurality of pixels, the plurality of pixels at least including a red pixel configured to perform display with red light, a green pixel configured to perform display with green light, and a blue pixel configured to perform display with blue light,

ultraviolet light serving as the excitation light is emitted from the light source, and

the phosphor layer includes a red phosphor layer disposed as the red pixel, the red phosphor layer being configured to emit red light using the ultraviolet light as the excitation light, a green phosphor layer disposed as the green pixel, the green phosphor layer being configured to emit green light using the ultraviolet light as the excitation light, and a blue phosphor layer disposed as the blue pixel, the blue phosphor layer being configured to emit blue light using the ultraviolet light as the excitation light.

5. The display device according to claim 3,

wherein the phosphor substrate includes a plurality of pixels, the plurality of pixels at least including a red pixel configured to perform display with red light, a green pixel configured to perform display with green light, and a blue pixel configured to perform display with blue light,

blue light serving as the excitation light is emitted from the light source,

the phosphor layer includes a red phosphor layer disposed as the red pixel, the red phosphor layer being configured to emit red light using the blue light as the excitation light, and a green phosphor layer disposed as the green pixel, the green phosphor layer being configured to emit green light using the blue light as the excitation light, and

the phosphor substrate includes a scattering layer serving as the blue pixel, the scattering layer being configured to scatter the blue light.

6. The display device according to claim 4, wherein the light source is an active matrix addressed light source, the active matrix addressed light source including a plurality of light-emitting elements disposed in response to the plurality of pixels and a plurality of driving elements configured to drive the respective plurality of light-emitting elements.

7. The display device according to claim 5, wherein the light source is an active matrix addressed light source, the active matrix addressed light source including a plurality of light-emitting elements disposed in response to the plurality of pixels and a plurality of driving elements configured to drive the respective plurality of light-emitting elements.

8. The display device according to claim 3, wherein the light source includes a light-emitting diode, an organic electroluminescent element, or an inorganic electroluminescent element.

9. The display device according to claim 3,

wherein the light source is a planar light source configured to emit light from a light-emitting surface, and

a liquid crystal element is disposed between the planar light source and the phosphor substrate, the liquid crystal element being configured to control a transmittance of light emitted from the planar light source for each pixel.

10. The display device according to claim 3, wherein the light source has directivity.

11. The display device according to claim 3, wherein a polarizer is disposed between the light source and the phosphor substrate, the polarizer having an extinction ratio of 10,000 or more at a wavelength of 435 nm or more and 480 nm or less.

12. The display device according to claim 3, wherein a color filter is disposed on any one of a top face and a bottom face of the phosphor layer.

13. The display device according to claim 3, wherein a black layer is disposed on at least one of a top face and a bottom face of the partition.

14. The display device according to claim 3, wherein a band pass filter is disposed between the light source and the phosphor substrate, the band pass filter transmitting light in a blue region and reflecting light in a green to near-infrared region.

15. An electronic apparatus comprising the display device according to claim 3.

19. The phosphor substrate according to claim 1, wherein the light scattering particles are composed of an inorganic material.

20. The phosphor substrate according to claim 3, wherein the light source is configured to emit one of first light and second light, a first main emission peak of the first light being at 360 nm to 410 nm, a second main emission peak of the second light being at 410 nm to 480 nm.

16. A display device comprising:

a phosphor substrate, the phosphor substrate comprising;

a substrate;

a phosphor layer disposed on the substrate, the phosphor layer emitting fluorescence using ultraviolet light or blue light;

a partition surrounding a side face of the phosphor layer; and

a black layer disposed on at least one of a top face and a bottom face of the partition,

wherein the phosphor layer includes at least one of a red phosphor layer and a green phosphor layer,

the red phosphor layer emits red light by being excited by the ultraviolet light or blue light,

the green phosphor layer emits green light by being excited by the ultraviolet light or blue light,

at least a portion of the partition in contact with the phosphor layer has light-scattering properties, is white, and is composed of a material containing a resin and light-scattering particles, the resin having a first refractive index, the light scattering particles having a second refractive index, the second refractive index being higher than the first refractive index, the light scattering particles being dispersed in the resin, each of the light scattering particles having a particle size of 100 nm to 500 nm, and

the partition has a tapered shape, and

a light source configured to emit the ultraviolet light or blue light toward the phosphor layer,

wherein the light source includes a light-emitting diode, an organic electroluminescent element, or an inorganic electroluminescent element.

17. The display device according to claim 16, wherein a ratio of the height of the partition to the breadth of a portion of the partition which contacts the substrate is 1 or less.

18. The display device according to claim 17, wherein the phosphor substrate further includes a blue pixel, the blue pixel including a scattering layer, the scattering layer including light scattering particles, and

the light scattering particles included in the at least the portion of the partition in contact with the phosphor layer and the light scattering particles included in the scattering layer are made of same material.