WO2013183751A1

WO2013183751A1 - Fluorescent substrate, light-emitting device, display device, and lighting device

Info

Publication number: WO2013183751A1
Application number: PCT/JP2013/065789
Authority: WO
Inventors: 別所　久徳; 充浩向殿; 悦昌藤田
Original assignee: シャープ株式会社
Priority date: 2012-06-07
Filing date: 2013-06-07
Publication date: 2013-12-12
Also published as: JP2013254651A

Abstract

The purpose of the present invention is to provide a fluorescent substrate, a light-emitting device, a display device, and a lighting device that have good viewing angle-color display characteristics so that hues do not change regardless of viewing angle. The fluorescent substrate comprises: a substrate on which a fluorescent layer that emits fluorescent light when excited by excitation light is formed on one surface thereof; and a light distribution adjustment layer that is formed between the substrate and the fluorescent layer and changes at least the emission direction of the fluorescent light emitted from the fluorescent layer.

Description

Phosphor substrate, light emitting device, display device, and illumination device

The present invention relates to a phosphor substrate, a light emitting device, a display device, and a lighting device that include a phosphor layer that emits fluorescence by excitation light.

In recent years, the need for flat panel displays has increased with the advancement of information technology in society. Examples of the flat panel display include a non-self-luminous liquid crystal display (LCD), a self-luminous plasma display (PDP), an inorganic electroluminescence (inorganic EL) display, and organic electroluminescence (hereinafter, “organic EL”). Or a display or the like.

Among these flat panel displays, in particular, in a liquid crystal display, an illumination device is generally provided as a light source on the back surface of a transmissive liquid crystal display element, and visibility is improved by irradiating the liquid crystal element from the back surface.
In such a liquid crystal display, the light emitted from the light source is generally non-polarized light, and more than 50% is absorbed by the polarizing plate disposed on the illumination light incident side of the liquid crystal display element. Low. Further, in a color liquid crystal display device that uses a white light source as a light source and arranges a micro color filter corresponding to the three primary colors or the four primary colors in the display surface and performs color display by additive color mixing, light exceeding 70% is emitted by the color filter. Since it is absorbed, the utilization efficiency of the light source light is very low, and increasing the efficiency of the light utilization efficiency has become a major issue.

In order to solve such a problem, for example, a pair of transparent substrates disposed with a certain gap so that the transparent electrode forming surfaces face each other, a liquid crystal layer sandwiched between the transparent substrates, and a pair of transparent substrates A liquid crystal display element having a voltage applying means for applying a voltage corresponding to an image signal to a matrix pixel formed by a transparent electrode, an illumination device emitting light from a blue region to a blue-green region, and a blue region to a blue-green region Wavelength-converting phosphor that emits red light using the light from the light source, wavelength-converting phosphor that emits green light using the light from the blue region to the blue-green region, and light other than the blue region to the blue-green region There is known a color display device including a color filter for cutting (see, for example, Patent Documents 1 and 2).

According to the configuration described in Patent Documents 1 and 2 and the like, since the blue light emitted from the blue light source can be used as it is as the blue display pixel, the light use efficiency can be increased. However, in a liquid crystal display device using a blue light source, when a display image is observed from an oblique direction inclined from the display surface, there is a problem that the viewing angle color display characteristic is deteriorated due to yellowish coloration.

In order to improve such deterioration in viewing angle color display characteristics, for example, a blue light source that emits blue light, a liquid crystal element having a liquid crystal cell and a pair of deflecting plates sandwiching the liquid crystal cell, and excited by the blue light are used. A liquid crystal display comprising: a phosphor that emits red fluorescence; a color filter having a phosphor that emits green fluorescence when excited by the blue light; and a light scattering film that scatters at least the blue light. An apparatus is known (see, for example, Patent Document 3).

Further, the light traveling direction is set between the light emitting layer and the outside so that the front luminance value and the luminance value in the direction of the viewing angle of 50 ° to 70 ° satisfy the luminance value of the front luminance value <50 ° to 70 °. There is also known an organic EL element in which a layer that is disturbed by reflection and refraction is provided and light in a wide-angle region with a large proportion of the amount of light is extracted from the relationship of the solid angle to improve the light extraction efficiency (for example, (See Patent Document 4).

Japanese Patent Publication “JP 2000-131683 A” Japanese Patent Publication “JP-A-2006-309225” Japanese Patent Publication “JP 2009-244383 A” Japanese Patent Publication “Japanese Patent Laid-Open No. 2004-296423”

However, in the display devices described in Patent Documents 1 and 2, since the blue light emitted from the blue light source can be used as it is as the blue display pixel, the light use efficiency can be increased, but in order to use the blue light source, The use of a phosphor in the pixel can increase the viewing angle of the emission profile of each pixel. On the other hand, when the emission profile is different among the pixels, there is a problem that the viewing angle color display characteristics are deteriorated.

In addition, since the phosphor layer is isotropic, that is, has the property of emitting light with equal energy in any direction, when considering the viewing angle characteristics of the brightness defined by the brightness level of the display, Due to the solid angle, it has a profile in which the luminance increases as the viewing angle increases when the viewing angle (angle formed by the surface perpendicular to the light emitting surface and the viewing direction) is from 0 ° to around 80 °. There are many. The direction of visually recognizing the display is mostly in the vicinity of 0 °, and even in a television, the viewing direction is up to about 60 ° (for example, see Reference 1). Therefore, in order to use light effectively, a means for optimizing the emission profile of the phosphor is necessary.

In addition, the liquid crystal display device described in Patent Document 3 has a light scattering film that scatters blue light to at least a blue pixel, so that the viewing angle of light emitted from the blue pixel can be increased, but the light scattering film Since only the function to scatter blue light is provided, the emission profiles of red and green pixels cannot be combined. That is, since there is no way to match the light emission profiles between the pixels, there is a problem that the color changes when the display image is viewed obliquely, and the viewing angle color display characteristics deteriorate.

In addition, since only the function of scattering blue light is provided, it is not possible to optimize the light emission profiles of the red pixel and the green pixel using phosphors, which is the same as the display devices described in Patent Documents 1 and 2. In addition, there is a problem that the light use efficiency is insufficient. Furthermore, since the base film constituting the light scattering film is interposed between the light scattering layer and the phosphor layer, the light emitted from one pixel is reflected at the interface between the base film and the light scattering layer, for example, and is adjacent. There is a problem that color blur occurs due to intrusion into a pixel.

Further, in the organic EL element described in Patent Document 4, since the means for matching the emission profile of the emitted light is not taken, the color changes when the display image is viewed obliquely, and the viewing angle color display characteristics are deteriorated. There was a problem to do.

The present invention has been made in view of the above circumstances, and adjusts the emission profile of fluorescence emitted from a phosphor layer to an optimum light distribution profile by combining the phosphor layer and the light distribution adjustment layer. And having a plurality of phosphor layers having different emission profiles, combining at least one light distribution adjusting layer suitable for each phosphor layer with the phosphor layer can produce different fluorescence layers. An object of the present invention is to provide a phosphor substrate, a light emitting device, a display device, and an illuminating device that can be combined with a light emission profile from a body layer and have a good viewing angle color display characteristic that does not change in color depending on the viewing angle. And

In order to solve the above problems, some aspects of the present invention provide the following phosphor substrate, light-emitting device, display device, and illumination device.
That is, the phosphor substrate of the present invention includes a substrate on which a phosphor layer that is excited by excitation light and emits fluorescence is formed on one surface, and a light distribution adjustment layer that changes at least the emission direction of fluorescence emitted from the phosphor layer. Is formed.

The light distribution adjusting layer is made of a light scattering material including a light-transmitting resin in which at least one particle is mixed.

発光 A light emitting device according to the present invention includes the phosphor substrate described in each of the above items and an excitation light source that emits the excitation light.

The light distribution adjustment layer is disposed between the substrate and the phosphor layer.

The light distribution adjusting layer has a luminance value L1 in a direction of a viewing angle of 0 ° that is a normal direction perpendicular to the emitting surface and a viewing angle of 0 ° from the emitting surface facing the incident surface of the excitation light on the substrate. The fluorescence is emitted so that the relationship with the luminance value L2 of a larger viewing angle satisfies at least L1 ≧ L2.
Further, the light distribution adjusting layer emits fluorescence so that a relationship between the luminance value L1 and the luminance value L3 in the direction of the viewing angle of 60 ° satisfies at least L3 / L1 ≧ 0.8. To do.

A light-reflective barrier is formed on at least one side surface along the thickness direction of the phosphor layer.
The excitation light incident surface side of the phosphor layer transmits at least excitation light in a peak wavelength region of the excitation light wavelength range and has a wavelength range of the fluorescence emitted from the phosphor layer. Among them, a wavelength selection layer that reflects at least fluorescence in a peak wavelength region is formed.

A low refractive index layer having a refractive index smaller than that of the phosphor layer is disposed between the phosphor layer and the wavelength selection layer.
Further, the low refractive index layer is further disposed between the light distribution adjusting layer and the phosphor layer.
Further, the refractive index of the low refractive index layer is in the range of 1 to 1.5.

The low refractive index layer is composed of a gas.
In addition, a plurality of the phosphor layers are arranged side by side on one surface of the substrate.
A plurality of the light distribution adjustment layers are arranged side by side so as to correspond to each of the plurality of phosphor layers.

A light absorption layer is further disposed between the phosphor layers adjacent to each other.
The light absorption layer may be further disposed between the light distribution adjustment layers adjacent to each other. The light absorption layer may be formed on at least one of an upper surface or a lower surface extending perpendicular to the thickness direction of the barrier.

At least a portion of the barrier that is in contact with the phosphor layer has light scattering properties.
In addition, at least a portion of the barrier that is in contact with the phosphor layer has an uneven shape.
Further, the light distribution adjusting layer is characterized by spreading along an exit surface facing the incident surface of the excitation light on the substrate.

表示 A display device according to the present invention includes the light-emitting device described in each of the above items.

The excitation light source emits excitation light in the ultraviolet wavelength region,
The phosphor layer comprises a red phosphor layer that constitutes a red pixel that emits red light by excitation light in the ultraviolet wavelength region, and a green phosphor layer that constitutes a green pixel that emits green light by excitation light in the ultraviolet wavelength region And a blue phosphor layer that constitutes a blue pixel that emits blue light by excitation light in the ultraviolet wavelength region.

The excitation light source emits excitation light in a blue wavelength region,
The phosphor layer includes a red phosphor layer that constitutes a red pixel that emits red light by the excitation light in the blue wavelength region, and a green phosphor layer that constitutes a green pixel that emits green light by the excitation light in the blue wavelength region. And a blue scatterer layer constituting a blue pixel that scatters the excitation light in the blue wavelength region.
Further, the blue scatterer layer and the light distribution adjustment layer are integrally formed.

The excitation light source emits excitation light in a blue wavelength region,
The phosphor layer includes a red phosphor layer that constitutes a red pixel that emits red light by the excitation light in the blue wavelength region, and a green phosphor layer that constitutes a green pixel that emits green light by the excitation light in the blue wavelength region. And a blue phosphor layer that constitutes a blue pixel that emits blue light by the excitation light in the blue wavelength region.

An active matrix driving element corresponding to the excitation light source is arranged.
Further, the excitation light source is composed of any one of a light emitting diode, an organic electroluminescence element, and an inorganic electroluminescence element.

The excitation light source is a planar light source, and a liquid crystal element capable of controlling the transmittance of the excitation light is formed between the excitation light source and the substrate.
The excitation light emitted from the excitation light source has directivity.

A polarizing plate having an extinction ratio of 10,000 or more at a wavelength of 435 nm or more and 480 nm or less is provided between the excitation light source and the substrate.
Further, a color filter is provided between at least one of the phosphor layer and the light distribution adjustment layer, or between the light distribution adjustment layer and the substrate.

The color change Δu′v ′ of the omnidirectional chromaticity u ′, v ′ with respect to the value of the chromaticity u ′, v ′ in the front direction of the light emitted from the light emitting surface is 0.01 or less. It is characterized by.
The light distribution adjusting layer or an external light antireflection layer for preventing reflection of external light may be provided so as to overlap the substrate.
Further, the refractive index of the external light antireflection layer has a refractive index gradient that gradually increases or decreases along the thickness direction.

照明 A lighting device according to the present invention includes the light-emitting device described in each of the above items.

According to the present invention, it is possible to adjust the light emission profile of the fluorescence emitted from the phosphor layer to an optimum light distribution profile, and to further match the light distribution profiles of the phosphor layers having different light emission profiles. Therefore, it is possible to provide a phosphor substrate, a light emitting device, a display device, and a lighting device having good viewing angle color display characteristics that do not change in color depending on the viewing angle.

It is a schematic sectional drawing which shows the 1st example of the conventional light-emitting device. It is a schematic sectional drawing which shows the 2nd example of the conventional light-emitting device. It is a schematic sectional drawing which shows 1st embodiment of the light-emitting device which concerns on this invention. It is a schematic sectional drawing which shows 2nd embodiment of the light-emitting device which concerns on this invention. It is a schematic sectional drawing which shows 3rd embodiment of the light-emitting device which concerns on this invention. It is a schematic sectional drawing which shows 4th embodiment of the light-emitting device which concerns on this invention. It is a schematic sectional drawing which shows 5th embodiment of the light-emitting device which concerns on this invention. It is a schematic sectional drawing which shows 6th embodiment of the light-emitting device which concerns on this invention. It is a schematic sectional drawing which shows 7th embodiment of the light-emitting device which concerns on this invention. It is a schematic sectional drawing which shows 8th embodiment of the light-emitting device which concerns on this invention. It is a schematic sectional drawing which shows 9th embodiment of the light-emitting device which concerns on this invention. It is a schematic sectional drawing which shows 10th embodiment of the light-emitting device which concerns on this invention. It is a schematic sectional drawing which shows 11th Embodiment of the light-emitting device which concerns on this invention. It is a schematic sectional drawing which shows 10th embodiment of the light-emitting device which concerns on this invention. It is a schematic sectional drawing which shows 13th embodiment of the light-emitting device which concerns on this invention. It is a schematic sectional drawing which shows 14th embodiment of the light-emitting device which concerns on this invention. It is a schematic sectional drawing which shows 15th embodiment of the light-emitting device which concerns on this invention. It is a schematic sectional drawing which shows 16th embodiment of the light-emitting device which concerns on this invention. It is a schematic sectional drawing which shows the organic EL element substrate which comprises the display apparatus which concerns on this invention. It is a schematic sectional drawing which shows the LED substrate which comprises the display apparatus which concerns on this invention. It is a schematic sectional drawing which shows the inorganic EL element substrate which comprises the display apparatus which concerns on this invention. It is a schematic sectional drawing which shows the organic electroluminescent display which comprises the display apparatus which concerns on this invention. 1 is a schematic plan view showing an organic EL display constituting a display device according to the present invention. It is a schematic sectional drawing of the display apparatus which concerns on this invention. It is a schematic sectional drawing of the display apparatus which concerns on this invention. It is an external view showing a mobile phone as an application example of a display device according to the present invention. It is an external view which shows the thin television which is one application example of the display apparatus which concerns on this invention. It is a schematic sectional drawing which shows embodiment of the organic electroluminescent illumination which concerns on this invention. It is a schematic sectional drawing which shows embodiment of the illuminating device which concerns on this invention. It is explanatory drawing explaining the viewing angle in embodiment.

"Conventional light-emitting device: first example"
First, in order to clarify the difference from the light emitting device of the present invention, the configuration and operation of a conventional light emitting device will be described.
FIG. 1 is a schematic cross-sectional view showing a first example of a conventional light emitting device.
A conventional light-emitting device 10 is generally configured by an excitation light source 11 that emits excitation light, and a substrate 13 that is arranged opposite to the excitation light source and on which a phosphor layer 12 that is excited by the excitation light and emits fluorescence is formed. ing.

Generally, when excitation light is incident on the phosphor layer from the outside, the phosphor layer is isotropic, that is, has a characteristic of emitting light with equal energy in any direction. Considering the viewing angle characteristic of the brightness defined by the brightness level of the display, the light emitted from the phosphor layer and extracted outside through the substrate, as shown in FIG. When the viewing angle (angle formed by the viewing direction and the surface perpendicular to the light emitting surface) is from 0 ° to around 80 °, the profile often has a higher luminance as the viewing angle increases. The direction of visually recognizing the display is mostly in the vicinity of 0 °, and the viewing direction is about 60 ° even on a television. Therefore, there is a problem that light cannot be used effectively.

"Conventional light-emitting device: Second example"
FIG. 2 is a schematic cross-sectional view showing a second example of a conventional light emitting device.
A conventional light emitting device 20 includes an excitation light source 11 that emits excitation light, a first phosphor layer 21 that is arranged to face the excitation light source, emits fluorescence when excited by the excitation light, and a second phosphor layer. 22, a third phosphor layer 23, and a substrate 13 in which a light absorption layer 24 is formed between the phosphor layers adjacent to each other.

When the light-emitting device is composed of a plurality of different phosphor layers as shown in FIG. 2, the light distribution profile of the light emitted from the phosphor layer and extracted outside through the substrate is as follows. May vary by layer. In such a case, there is a problem that the tint changes between when the display image is viewed from the front and when viewed from an oblique direction, and the viewing angle color display characteristics are degraded.

Hereinafter, embodiments of a phosphor substrate, a light emitting device, a display device, and an illumination device according to the present invention will be described with reference to the drawings. The following embodiments are specifically described for better understanding of the gist of the invention, and do not limit the present invention unless otherwise specified. In addition, in the drawings used in the following description, in order to make the features of the present invention easier to understand, there is a case where a main part is shown in an enlarged manner for convenience, and the dimensional ratio of each component is the same as the actual one. Not necessarily.

In addition, in each embodiment of the phosphor substrate, the light emitting device, the display device, and the lighting device described in detail below, the term viewing angle indicates that the phosphor Fm is formed as shown in FIG. ) A direction along the light emission surface FPa of the phosphor substrate FP made of the substrate P is defined as a viewing angle of 90 °, and a direction perpendicular to the emission surface is defined as a viewing angle of 0 °. For example, when the viewing angle is 45 °, the angle is inclined at 45 ° between the direction (90 °) along the emission surface of the phosphor substrate and the direction (0 °) perpendicular to the emission surface. Indicates.

"Light Emitting Device"
(1) First Embodiment FIG. 3 is a schematic cross-sectional view showing a light emitting device according to the first embodiment.
The light emitting device 30 includes an excitation light source 11 that emits excitation light, a substrate 13 that is disposed to face the excitation light source, and is formed with a phosphor layer 12 that is excited by the excitation light and emits fluorescence. A light distribution adjusting layer 31 that is formed between the phosphor layers 12 and changes the emission direction of the fluorescence emitted from at least the phosphor layers is roughly constituted.

The phosphor layer 12 is formed on one surface of the substrate 13, and a light distribution adjustment layer 31 is formed between the phosphor layer 12 and the substrate 13.

Hereinafter, although each structural member which comprises the light-emitting device 30, and its formation method are demonstrated concretely, this embodiment is not limited to these structural members and a formation method.

As the excitation light source 11 for exciting the phosphor, a light source that emits ultraviolet light or blue light is used. Examples of such a light source include an ultraviolet light emitting diode (hereinafter sometimes abbreviated as “ultraviolet LED”), a blue light emitting diode (hereinafter sometimes abbreviated as “blue LED”), and an ultraviolet light emitting inorganic electroluminescence. An element (hereinafter sometimes abbreviated as “ultraviolet light emitting inorganic EL element”), a blue light emitting inorganic electroluminescence element (hereinafter sometimes abbreviated as “blue light emitting inorganic EL element”), an ultraviolet light emitting organic electroluminescence element ( Hereinafter, light emitting elements such as “ultraviolet light emitting organic EL element” and blue light emitting organic electroluminescence element (hereinafter sometimes abbreviated as “blue light emitting organic EL element”) may be used. Examples of the excitation light source 11 include those described above, but are not limited thereto.

Further, by directly switching the excitation light source 11, it is possible to control ON / OFF of light emission for displaying an image. However, a liquid crystal or the like is provided between the excitation light source 11 and the phosphor layer 12. It is also possible to control ON / OFF of light emission by arranging a layer having a proper shutter function and controlling it. Moreover, it is also possible to control ON / OFF of both the layer having a shutter function such as liquid crystal and the excitation light source 11.

The phosphor layer 12 absorbs excitation light from light emitting elements such as an ultraviolet LED, a blue LED, an ultraviolet light emitting inorganic EL element, a blue light emitting inorganic EL element, an ultraviolet light emitting organic EL element, and a blue light emitting organic EL element. The red phosphor layer that emits blue light, the green phosphor layer, and the blue phosphor layer.
The red phosphor layer, the green phosphor layer, and the blue phosphor layer are made of, for example, a thin film having a rectangular shape in plan view.

Further, it is preferable to add phosphors emitting light of cyan and yellow to each pixel constituting the phosphor layer 13 as necessary. Here, by setting the color purity of each pixel emitting light to cyan and yellow outside the triangle connected by the color purity points of red, green, and blue light emitting pixels on the chromaticity diagram, red, The color reproduction range can be further expanded as compared with a display device that uses pixels that emit three primary colors of green and blue.

The phosphor layer 12 may be composed of only the phosphor material exemplified below, and may optionally contain additives, etc., and these materials are in a polymer material (binding resin) or an inorganic material. The configuration may be distributed in a distributed manner.
As the phosphor material constituting the phosphor layer 12, a known phosphor material can be used. Such phosphor materials are classified into organic phosphor materials and inorganic phosphor materials. Although these specific compounds are illustrated below, this embodiment is not limited to these materials.

As organic phosphor materials, as blue fluorescent dyes that convert ultraviolet excitation light into blue light emission, stilbenzene dyes: 1,4-bis (2-methylstyryl) benzene, trans-4,4′-diphenylstil Benzene, coumarin dyes: 7-hydroxy-4-methylcoumarin, 2,3,6,7-tetrahydro-11-oxo-1H, 5H, 11H- [1] benzopyrano [6,7,8-ij] quinolidine- Ethyl 10-carboxylate (coumarin 314), 10-acetyl-2,3,6,7-tetrahydro-1H, 5H, 11H- [1] benzopyrano [6,7,8-ij] quinolizin-11-one (coumarin) 334), anthracene dyes: 9,10 bis (phenylethynyl) anthracene, perylene and the like.

Organic phosphor materials include coumarin dyes: 2,3,5,6-1H, 4H-tetrahydro-8-trifluoromethylquinolidine as green fluorescent dyes that convert ultraviolet and blue excitation light into green light emission (9,9a, 1-gh) coumarin (coumarin 153), 3- (2′-benzothiazolyl) -7-diethylaminocoumarin (coumarin 6), 3- (2′-benzoimidazolyl) -7-N, N-diethylaminocoumarin (Coumarin 7), 10- (benzothiazol-2-yl) -2,3,6,7-tetrahydro-1H, 5H, 11H- [1] benzopyrano [6,7,8-ij] quinolizin-11-one (Coumarin 545), coumarin 545T, coumarin 545P, naphthalimide dyes: basic yellow 51, solvent yellow 11, solvent Yellow 98, Solvent Yellow 116, Solvent Yellow 43, Solvent Yellow 44, Perylene dyes: Lumogen Yellow, Lumogen Green, Solvent Green 5, fluorescein dye, azo dye, phthalocyanine dye, anthraquinone dye, quinacridone dye , Isoindolinone dyes, thioindigo dyes, dioxazine dyes and the like.

Organic phosphor materials include cyanine dyes: 4-dicyanomethylene-2-methyl-6- (p-dimethylaminostyryl) -4H as red fluorescent dyes that convert ultraviolet and blue excitation light into red light emission. -Pyran, pyridine dye: 1-ethyl-2- [4- (p-dimethylaminophenyl) -1,3-butadienyl] -pyridinium-perchlorate (pyridine 1), and xanthene dye: rhodamine B, rhodamine 6G , Rhodamine 3B, rhodamine 101, rhodamine 110, basic violet 11, sulforhodamine 101, basic violet 11, basic red 2, perylene dye: lumogen orange, lumogen pink, rumogen red, solvent orange 55, oxazine dye, chrysene dye, Thiofurabi Dye, pyrene dye, anthracene dye, acridone dye, acridine dye, fluorene dye, terphenyl dye, ethene dye, butadiene dye, hexatriene dye, oxazole dye, coumarin dye, stilbene And dyes such as di- and triphenylmethane dyes, thiazole dyes, thiazine dyes, naphthalimide dyes and anthraquinone dyes.
When an organic phosphor material is used as each color phosphor, it is desirable to use a dye that is not easily degraded by blue light, ultraviolet light, or external light of the backlight. In this respect, it is particularly preferable to use a perylene dye having excellent light resistance and a high quantum yield.

As an inorganic phosphor material, Sr ₂ P ₂ O ₇ : Sn ⁴⁺ , Sr ₄ Al ₁₄ O ₂₅ : Eu ²⁺ , BaMgAl ₁₀ O ₁₇ : Eu are used as blue phosphors that convert ultraviolet excitation light into blue light emission. ²⁺ , SrGa ₂ S ₄ : Ce ³⁺ , CaGa ₂ S ₄ : Ce ³⁺ , (Ba, Sr) (Mg, Mn) Al ₁₀ O ₁₇ : Eu ²⁺ , (Sr, Ca, Ba ₂ , 0Mg) ₁₀ (PO ₄ ) ₆ Cl ₂ : Eu ²⁺ , BaAl ₂ SiO ₈ : Eu ²⁺ , Sr ₂ P ₂ O ₇ : Eu ²⁺ , Sr ₅ (PO ₄ ) ₃ Cl: Eu ²⁺ , (Sr, Ca, Ba) ₅ (PO ₄ ) ₃ Cl: Eu ²⁺ , BaMg ₂ Al ₁₆ O ₂₇ : Eu ²⁺ , (Ba, Ca) ₅ (PO ₄ ) ₃ Cl: Eu ²⁺ , Ba ₃ MgSi ₂ O ₈ : Eu ²⁺ , Sr ₃ MgSi ₂ O ₈ : Eu ^{2+ and the} like.

Examples of inorganic phosphor materials include (BaMg) Al ₁₆ O ₂₇ : Eu ²⁺ , Mn ²⁺ , Sr ₄ Al ₁₄ O ₂₅ : Eu ²⁺ , as green phosphors that convert ultraviolet and blue excitation light into green light emission. (SrBa) Al ₁₂ Si ₂ O ₈ : Eu ²⁺ , (BaMg) ₂ SiO ₄ : Eu ²⁺ , Y ₂ SiO ₅ : Ce ³⁺ , Tb ³⁺ , Sr ₂ P ₂ O ₇ -Sr ₂ B ₂ O ₅ : Eu ²⁺ , (BaCaMg) ₅ (PO ₄ ) ₃ Cl: Eu ²⁺ , Sr ₂ Si ₃ O ₈ -2SrCl ₂ : Eu ²⁺ , Zr ₂ SiO ₄ , MgAl ₁₁ O ₁₉ : Ce ³⁺ , Tb ³⁺ , Ba ₂ SiO ₄ : Eu ²⁺ , Sr ₂ SiO ₄ : Eu ²⁺ , (BaSr) SiO ₄ : Eu ^{2+ and the} like.

As an inorganic phosphor material, Y ₂ O ₂ S: Eu ³⁺ , YAlO ₃ : Eu ³⁺ , Ca ₂ Y ₂ (SiO ₄ ) ₆ is used as a red phosphor that converts ultraviolet and blue excitation light into red light emission. : Eu ³⁺ , LiY ₉ (SiO ₄ ) ₆ O ₂ : Eu ³⁺ , YVO ₄ : Eu ³⁺ , CaS: Eu ³⁺ , Gd ₂ O ₃ : Eu ³⁺ , Gd ₂ O ₂ S: Eu ³⁺ , Y (P, V ) O ₄ : Eu ³⁺ , Mg ₄ GeO _5.5 F: Mn ⁴⁺ , Mg ₄ GeO ₆ : Mn ⁴⁺ , K ₅ Eu _2.5 (WO ₄ ) _6.25 , Na ₅ Eu _2.5 (WO ₄ ) _{_{_{_{6.25, K 5 Eu 2.5 (MoO}}}} 4) 6.25, Na 5 Eu 2.5 (MoO 4) 6.25 , and the like.

The inorganic phosphor material may be subjected to surface modification treatment as necessary. Examples of the surface modification treatment include chemical treatment using a silane coupling agent, physical treatment using addition of submicron order fine particles, and combinations thereof.
In consideration of stability such as deterioration due to excitation light and light emission, it is preferable to use an inorganic phosphor material.

When an inorganic phosphor material is used, the average particle diameter (d ₅₀ ) is preferably 0.5 to 50 μm. If the average particle size of the inorganic phosphor material is less than 0.5 μm, the luminous efficiency of the phosphor is drastically lowered. If the average particle size of the inorganic phosphor material exceeds 50 μm, it becomes very difficult to form a planarizing film, and a gap is formed between the phosphor layer 12 and the excitation light source 11 (excitation light source). 11 and the phosphor layer 12 (refractive index: about 2.3), the light from the excitation light source 11 does not efficiently reach the phosphor layer 12, and the phosphor layer. There arises a problem that the luminous efficiency of 12 is lowered. Further, it is difficult to flatten the phosphor layer 12 and it becomes impossible to form a liquid crystal layer (the distance between the electrodes sandwiching the liquid crystal layer varies and the electric field is not applied uniformly, so the liquid crystal layer is uniform. The problem of not working etc. occurs.

The phosphor layer 12 is prepared by using a phosphor layer forming coating solution obtained by dissolving and dispersing the phosphor material and the resin material in a solvent, using a spin coating method, a dipping method, a doctor blade method, a discharge coating method, Known wet processes such as coating methods such as spray coating, ink jet methods, letterpress printing methods, intaglio printing methods, screen printing methods, microgravure coating methods, and the like, and resistance heating vapor deposition method, electron beam ( EB) It can be formed by a known dry process such as a vapor deposition method, a molecular beam epitaxy (MBE) method, a sputtering method, an organic vapor deposition (OVPD) method, or a formation method such as a laser transfer method.

Moreover, the phosphor layer 12 can be patterned by a photolithography method by using a photosensitive resin as a polymer resin. Here, as the photosensitive resin, a photosensitive resin (photocurable resist material) having a reactive vinyl group such as an acrylic acid resin, a methacrylic acid resin, a polyvinyl cinnamate resin, or a hard rubber resin is used. It is possible to use one kind or a mixture of several kinds.

Also, wet process such as ink jet method, relief printing method, intaglio printing method, screen printing method, dispenser method, resistance heating vapor deposition method using shadow mask, electron beam (EB) vapor deposition method, molecular beam epitaxy (MBE) method, It is also possible to directly pattern the phosphor material by a known dry process such as a sputtering method or an organic vapor deposition (OVPD) method, or a laser transfer method.

The binder resin material is preferably a translucent resin. Examples of the resin material include acrylic resin, melamine resin, polyester resin, polyurethane resin, alkyd resin, epoxy resin, butyral resin, polysilicone resin, polyamide resin, polyimide resin, melanin resin, phenol resin, polyvinyl alcohol, polyvinyl Hydrine, hydroxyethyl cellulose, carboxymethyl cellulose, aromatic sulfonamide resin, urea resin, benzoguanamine resin, triacetyl cellulose (TAC), polyethersulfone, polyetherketone, nylon, polystyrene, melamine beads, polycarbonate, polyvinyl chloride, Polyvinylidene chloride, polyvinyl acetate, polyethylene, polymethyl methacrylate, poly MBS, medium density polyethylene, high density polyethylene, tetrafluoroethylene Oroechiren, poly trifluorochloroethylene, polytetrafluoroethylene and the like.

The thickness of the phosphor layer 12 is usually about 100 nm to 100 μm, but preferably 1 μm to 100 μm. If the film thickness is less than 100 nm, it is impossible to sufficiently absorb the light emitted from the excitation light source 11, so that the light emission efficiency is reduced, or the required color is mixed with blue transmitted light, resulting in color purity. Problems such as deterioration. Furthermore, in order to increase absorption of light emitted from the excitation light source 11 and reduce blue transmitted light to such an extent that the color purity is not adversely affected, the film thickness is preferably 1 μm or more. Further, when the film thickness exceeds 100 μm, the blue light emission from the excitation light source 11 is already sufficiently absorbed, so that the efficiency is not increased but only the material is consumed and the material cost is increased.

Since the substrate 13 needs to emit light emitted from the phosphor layer 12 to the outside, it is necessary to transmit the light emission in the light emitting region of the phosphor. For example, an inorganic material substrate made of glass, quartz, etc., polyethylene Examples include plastic substrates made of terephthalate, polycarbazole, polyimide, and the like, but the present embodiment is not limited to these substrates.

It is preferable to use a plastic substrate from the viewpoint that it is possible to form a bent portion or a bent portion without any stress. Further, from the viewpoint that the gas barrier property can be improved, a substrate obtained by coating a plastic substrate with an inorganic material is more preferable. As a result, when the plastic substrate is used as the substrate of the organic EL element, the deterioration of the organic EL element due to the permeation of moisture, which is the biggest problem (the organic EL element is known to deteriorate even with a low amount of moisture, in particular). Can be eliminated.

The light distribution adjustment layer 31 is provided between the phosphor layer 12 and the substrate 13 and has a property of changing the light distribution profile of the fluorescence incident on the substrate 13 out of the fluorescence emitted from the phosphor layer 12. . The light distribution adjusting layer 31 may be made of a light scattering material containing at least one particle and a light-transmitting resin.

The particles may be either inorganic materials or organic materials.
When an inorganic material is used as the particle, for example, a particle (fine particle) mainly composed of an oxide of at least one metal selected from the group consisting of silicon, titanium, zirconium, aluminum, indium, zinc, tin and antimony. However, the present embodiment is not limited to these inorganic materials.

Moreover, when using particles (inorganic fine particles) made of an inorganic material as particles, for example, silica beads (refractive index: 1.44), alumina beads (refractive index: 1.63), titanium oxide beads ( Anatase type refractive index: 2.52, rutile type refractive index: 2.71), zirconia bead (refractive index: 2.05), zinc oxide beads (refractive index: 2.00), barium titanate (BaTiO) ₃ ) (refractive index: 2.4) and the like, but this embodiment is not limited to these inorganic fine particles.

When particles (organic fine particles) composed of an organic material are used as the particles, for example, polymethyl methacrylate beads (refractive index: 1.49), acrylic beads (refractive index: 1.50), acrylic-styrene Polymer beads (refractive index: 1.54), melamine beads (refractive index: 1.57), high refractive index melamine beads (refractive index: 1.65), polycarbonate beads (refractive index: 1.57), styrene beads (Refractive index: 1.60), crosslinked polystyrene beads (refractive index: 1.61), polyvinyl chloride beads (refractive index: 1.60), melamine formaldehyde beads (refractive index: 1.65), benzoguanamine-melamine formaldehyde Examples include beads (refractive index: 1.68) and silicone beads (refractive index: 1.50). It is not limited to the organic fine particles.

As the translucent resin, for example, acrylic resin (refractive index: 1.49), melamine resin (refractive index: 1.57), nylon (refractive index: 1.53), polystyrene (refractive index: 1.60). , Melamine beads (refractive index: 1.57), polycarbonate (refractive index: 1.57), polyvinyl chloride (refractive index: 1.60), polyvinylidene chloride (refractive index: 1.61), polyvinyl acetate ( Refractive index: 1.46), polyethylene (refractive index: 1.53), polymethyl methacrylate (refractive index: 1.49), poly MBS (refractive index: 1.54), medium density polyethylene (refractive index: 1) .53), high density polyethylene (refractive index: 1.54), tetrafluoroethylene (refractive index: 1.35), poly (trifluoroethylene chloride) (refractive index: 1.42), polytetrafluoroethylene (refractive index) : .35), and the like, but the present embodiment is not limited to these resins.

The light scatterer material can be formed by dispersing particles in the above-described translucent resin. The disperser is equipped with a general agitator equipped with mechanisms such as propeller blades, turbine blades, and battle blades at the tip, or a toothed disk-shaped impeller mechanism with circular saw blades bent alternately up and down. High-speed rotary centrifugal radiation stirrer, ultrasonic emulsification dispersion device that generates ultrasonic energy intensively for dispersion treatment, or beads filled in a container and rotated to grind and crush raw materials -Although the dispersion method by the bead mill apparatus which performs dispersion | distribution etc. is mentioned, it is not limited to these methods.

The particle size, the refractive index, the concentration, the refractive index of the translucent resin, and the film thickness of the light distribution adjusting layer 31 of the particles constituting the light scatterer material depend on the light distribution profile of the fluorescence emitted from the phosphor layer 12. To optimize.

For example, when the light distribution profile of the phosphor layer 12 is clearly higher than the luminance value in the direction of the viewing angle of 0 °, the luminance value of the oblique direction component is larger. Therefore, it is necessary to suppress the brightness to a value equal to or less than the luminance value in the 0 ° direction, so that particles having a particle size equivalent to the wavelength of light are used, the concentration of the particles is increased, or the particles and the translucent resin are used. It is preferable to increase the difference in refractive index or increase the film thickness.

The average particle size of the particles is more preferably 150 nm to 900 nm. As a result, the particle size of the particles is about the same as the wavelength with respect to the light in the entire visible light region, and the light hitting the particles causes Mie scattering in which forward scattering and side scattering are dominant, and in an oblique direction. The direction of the traveling light can be changed.

The concentration of the particles with respect to the translucent resin is more preferably 0.5 wt% to 5 wt%. When it is 0.5 wt% or less, sufficient scattering characteristics cannot be obtained, and as a result, light in an oblique direction is lost as it is. On the other hand, if it is 5 wt% or more, the backscattered light component increases, resulting in a low transmittance.

More preferably, the difference in refractive index between the particles and the translucent resin is 0.05 or more. If it is 0.05 or less, sufficient scattering characteristics cannot be obtained, and as a result, light in an oblique direction passes through as it is.

The film thickness of the light scattering layer 31 is more preferably 1 μm to 15 μm. If it is 1 μm or less, sufficient scattering characteristics cannot be obtained, and as a result, light in an oblique direction passes through as it is. On the other hand, when it is 15 μm or more, the backscattered light component increases, and as a result, the transmittance decreases.

Further, the light distribution adjustment layer 31 is not limited to the above-described configuration including the particles and the translucent resin. For example, the light distribution adjustment layer 31 is incident by refraction and reflection by forming a random fine structure on the surface. It may be a layer that changes the direction of light.

With reference to FIG. 3, the light emission in the light-emitting device 30 is demonstrated.
In the light emitting device 30, when excitation light enters the phosphor layer 12 from the excitation light source 11, light is emitted from the phosphor layer 12 isotropically, that is, with equal energy in any direction. The luminance viewing angle characteristic of this light is such that the larger the viewing angle is, the larger the viewing angle is between 0 ° and 80 °, since the viewing angle (the angle formed by the surface perpendicular to the light emitting surface and the viewing direction) is related to the solid angle. Has a high profile. Then, this light is scattered by the light distribution adjusting layer 31 provided between the phosphor layer 12 and the substrate 13, and the traveling direction of the light is changed. At this time, the optical path length in the light distribution adjustment layer 31 is longer in the latter case between light incident perpendicularly to the surface of the light distribution adjustment layer 31 and light incident in an oblique direction.

Therefore, the latter light is often scattered in the light distribution adjusting layer 31 with respect to the former. In other words, a light emission profile in which the luminance increases as the viewing angle increases is changed to a light emission profile in which at least the luminance in the 0 ° direction is equal to or higher than the luminance in the oblique direction through the light distribution adjustment layer 31. be able to. As a result, a light-emitting device that does not change in brightness when viewed from any direction can be obtained. Further, in this configuration, since the substrate 13 exists between the light distribution adjustment layer 31 and the outside, the influence on the characteristics of the light distribution adjustment layer 31 due to changes in the surrounding environment can be minimized.

(2) Second Embodiment FIG. 4 is a schematic cross-sectional view showing a second embodiment of the light emitting device. 4, the same components as those of the light emitting device 30 shown in FIG. 3 are denoted by the same reference numerals, and the description thereof is omitted.
The light emitting device 40 changes an emission direction of fluorescence emitted from the excitation light source 11 that emits excitation light, a phosphor layer 12 that emits fluorescence when excited by the excitation light on the excitation light source, and at least the phosphor layer 12. The light distribution adjusting layer 31 is generally configured.

With reference to FIG. 4, the light emission in the light-emitting device 40 is demonstrated.
In the light emitting device 40, when excitation light is incident on the phosphor layer 12 from the excitation light source 11, light is emitted from the phosphor layer 12 isotropically, that is, with equal energy in any direction. The luminance viewing angle characteristic of this light is such that the larger the viewing angle is, the larger the viewing angle is between 0 ° and 80 °, since the viewing angle (the angle formed by the surface perpendicular to the light emitting surface and the viewing direction) is related to the solid angle. Has a high profile. Then, this light enters the light distribution adjustment layer 31 and is scattered in the light distribution adjustment layer 31 to change the traveling direction of the light. At this time, the optical path length in the light distribution adjustment layer 31 is longer in the latter case between light incident perpendicularly to the surface of the light distribution adjustment layer 31 and light incident in an oblique direction.

Therefore, the latter light is often scattered in the light distribution adjusting layer 31 with respect to the former. In other words, a light emission profile in which the luminance increases as the viewing angle increases is changed to a light emission profile in which at least the luminance in the 0 ° direction is equal to or higher than the luminance in the oblique direction through the light distribution adjustment layer 31. be able to. As a result, a light-emitting device that does not change in brightness when viewed from any direction can be obtained. Further, in this configuration, the light emitted from the light distribution adjustment layer 31 is extracted as it is without passing through other layers, so that the emission profile can be optimized only by adjusting the light distribution adjustment layer 31. Can do.

(3) Third Embodiment FIG. 5 is a schematic cross-sectional view showing a light emitting device according to a third embodiment. In FIG. 5, the same components as those of the light emitting device 30 shown in FIG.
The light-emitting device 50 includes an excitation light source 11 that emits excitation light, a substrate 13 that is disposed opposite to the excitation light source and on which a phosphor layer 12 that is excited by the excitation light and emits fluorescence is formed, the substrate 13, and the substrate At least the phosphor layer 12 along the stacking direction of the substrate 13 and the light distribution adjustment layer 31 that is formed between the phosphor layers 12 and changes the emission direction of at least fluorescence emitted from the phosphor layer. It is generally composed of a light reflective barrier 51 on one or more sides.

Examples of the light-reflective barrier 51 include a structure in which a reflective metal powder such as Al, Ag, Au, Cr, or an alloy thereof, or a reflective resin film made of a resin containing metal particles is formed. However, the present embodiment is not limited to these.

Further, the barrier 51 may have a light scattering property at least in a portion in contact with the phosphor layer 12. A material for forming the barrier 51 itself (hereinafter referred to as “barrier material”) or a material for forming a light scattering layer (light scattering film) provided on the side surface of the barrier 51 (hereinafter referred to as “light scattering film material”). For example, a material containing a resin and light scattering particles is used.

Examples of the resin include acrylic resin (refractive index: 1.49), melamine resin (refractive index: 1.57), nylon (refractive index: 1.53), polystyrene (refractive index: 1.60), melamine beads. (Refractive index: 1.57), polycarbonate (refractive index: 1.57), polyvinyl chloride (refractive index: 1.60), polyvinylidene chloride (refractive index: 1.61), polyvinyl acetate (refractive index: 1.46), polyethylene (refractive index: 1.53), polymethyl methacrylate (refractive index: 1.49), poly MBS (refractive index: 1.54), medium density polyethylene (refractive index: 1.53) , High density polyethylene (refractive index: 1.54), tetrafluoroethylene (refractive index: 1.35), poly (ethylene trifluoride) chloride (refractive index: 1.42), polytetrafluoroethylene (refractive index: 1.2. 3 ) And the like, but the present embodiment is not limited to these resins.

The light scattering particles may be either an inorganic material or an organic material.
When an inorganic material is used as the light scattering particle, for example, the main component is an oxide of at least one metal selected from the group consisting of silicon, titanium, zirconium, aluminum, indium, zinc, tin, and antimony. Examples include particles (fine particles), but the present embodiment is not limited to these inorganic materials.

Further, when particles (inorganic fine particles) made of an inorganic material are used as the light scattering particles, for example, silica beads (refractive index: 1.44), alumina beads (refractive index: 1.63), oxidation Titanium beads (anatase type refractive index: 2.50, rutile type refractive index: 2.70), zirconia oxide beads (refractive index: 2.05), zinc oxide beads (refractive index: 2.00), titanic acid barium (BaTiO ₃₎ (refractive index: 2.4), but like the present embodiment is not limited to these inorganic fine particles.

When particles (organic fine particles) made of an organic material are used as the light scattering particles, for example, polymethyl methacrylate beads (refractive index: 1.49), acrylic beads (refractive index: 1.50), acrylic -Styrene copolymer beads (refractive index: 1.54), melamine beads (refractive index: 1.57), high refractive index melamine beads (refractive index: 1.65), polycarbonate beads (refractive index: 1.57) Styrene beads (refractive index: 1.60), crosslinked polystyrene beads (refractive index: 1.61), polyvinyl chloride beads (refractive index: 1.60), benzoguanamine-melamine formaldehyde beads (refractive index: 1.68) And silicone beads (refractive index: 1.50), and the like, but this embodiment is not limited to these organic fine particles.

The barrier material and the light scattering film material may contain an antifoaming agent / leveling agent such as a photopolymerization initiator, dipropylene glycol monomethyl ether, and 1- (2-methoxy-2-methylethoxy) -2-propanol. .

Furthermore, the barrier 51 may be white. Specifically, the barrier material and the light scattering film material may contain a white resist.
Examples of the white resist include a carboxyl group-containing resin having no aromatic ring, a photopolymerization initiator, a hydrogenated epoxy compound, a rutile type titanium oxide, and a material containing a diluent.

By selecting an alkali-soluble resin as the resin constituting the barrier material and adding a photopolymerizable monomer, a photopolymerization initiator, a solvent, etc., the barrier material and the light scattering film material can be made into a photoresist. Alternatively, the light scattering layer provided on the side surface of the barrier 15 can be patterned by photolithography.

With reference to FIG. 5, the light emission in the light-emitting device 50 is demonstrated.
In the light emitting device 50, when excitation light is incident on the phosphor layer 12 from the excitation light source 11, light is emitted from the phosphor layer 12 isotropically, that is, with equal energy in any direction. The luminance viewing angle characteristic of this light is such that the larger the viewing angle is, the larger the viewing angle is between 0 ° and 80 °, since the viewing angle (the angle formed by the surface perpendicular to the light emitting surface and the viewing direction) is related to the solid angle. Has a high profile. Then, this light enters the light distribution adjustment layer 31 and is scattered in the light distribution adjustment layer 31 to change the traveling direction of the light. At this time, the optical path length in the light distribution adjustment layer 31 is longer in the latter case between light incident perpendicularly to the surface of the light distribution adjustment layer 31 and light incident in an oblique direction.

Therefore, the latter light is often scattered in the light distribution adjusting layer 31 with respect to the former. In other words, a light emission profile in which the luminance increases as the viewing angle increases is changed to a light emission profile in which at least the luminance in the 0 ° direction is equal to or higher than the luminance in the oblique direction through the light distribution adjustment layer 31. be able to. As a result, a light-emitting device that does not change in brightness when viewed from any direction can be obtained. Further, in this configuration, since the light-reflective barrier 51 is provided on the side surface of the phosphor layer 12, among the fluorescence emitted from the phosphor layer 12, the fluorescence component reflected at the interface of the substrate 13 and the fluorescence The fluorescent component that emits light on the side opposite to the light extraction side of the body layer 12 is reflected by the side surface of the light-reflective barrier 51 and recycled again to a component that can be extracted to the substrate 13 side.

That is, by providing the light-reflective barrier 51 on the side surface of the phosphor layer 12, it is possible to efficiently extract the fluorescent component emitted from the phosphor layer 12 to the outside. If the portion of the barrier 51 in contact with the phosphor layer 12 has light scattering properties, for example, when the fluorescent component that has been totally reflected once by the substrate is reflected by the barrier 51 and reenters the substrate, first, the substrate The fluorescent component totally reflected at 13 and incident on the barrier 51 is reflected (scattered) by the barrier 51 at an angle different from the incident angle and is incident on the substrate at an angle different from the first angle. There is little possibility of being reflected, and it can be taken out to the outside. That is, by providing the light-scattering barrier 51 on the side surface of the phosphor layer 12, the fluorescent component emitted from the phosphor layer 12 can be taken out more efficiently.

(4) Fourth Embodiment FIG. 6 is a schematic cross-sectional view showing a light emitting device according to a fourth embodiment. In FIG. 6, the same components as those of the light emitting device 30 shown in FIG.
The light-emitting device 60 includes an excitation light source 11 that emits excitation light, a substrate 13 that is disposed to face the excitation light source, and is formed with a phosphor layer 12 that is excited by the excitation light and emits fluorescence. At least the phosphor layer 12 along the stacking direction of the substrate 13 and the light distribution adjustment layer 31 that is formed between the phosphor layers 12 and changes the emission direction of at least fluorescence emitted from the phosphor layer. A light-reflective barrier 51 is formed on one or more side surfaces, and a wavelength selective transmission / reflection layer 61 formed on the phosphor layer 12 on the incident surface side on which excitation light is incident.

That is, the wavelength selective transmission / reflection layer 61 is provided on the incident surface of the excitation light of the phosphor layer 12 and the upper surface of the barrier 51, and transmits at least light corresponding to the peak wavelength of the excitation light from the excitation light source 11. It is a layer having a characteristic of reflecting at least light corresponding to the emission peak wavelength of the body layer 12.

Of the fluorescence emitted isotropically in all directions from the phosphor layer 12, the fluorescent component directed toward the back side of the light emitting device 60 is efficiently transmitted by the wavelength selective transmission / reflection layer 61 provided on the incident surface of the phosphor layer 12. Therefore, the light can be reflected in the front direction, and the light emission efficiency can be improved.

Examples of the wavelength selective transmission / reflection layer 61 include a dielectric multilayer film, a metal thin film glass, an inorganic material substrate made of quartz or the like, a plastic substrate made of polyethylene terephthalate, polycarbazole, polyimide, or the like. However, it is not limited to these substrates.

With reference to FIG. 6, the light emission in the light-emitting device 60 is demonstrated.
In the light emitting device 60, when excitation light is incident on the phosphor layer 12 from the excitation light source 11, light is emitted from the phosphor layer 12 isotropically, that is, with equal energy in any direction. The luminance viewing angle characteristic of this light is such that the larger the viewing angle is, the larger the viewing angle is between 0 ° and 80 °, since the viewing angle (the angle formed by the surface perpendicular to the light emitting surface and the viewing direction) is related to the solid angle. Has a high profile. Then, this light enters the light distribution adjustment layer 31 and is scattered in the light distribution adjustment layer 31 to change the traveling direction of the light. At this time, the light path length in the light distribution adjusting layer 31 is longer in the light distribution layer 31 for light incident perpendicularly to the surface of the light scattering layer 31 and light incident in an oblique direction.

That is, by providing the light-reflective barrier 51 on the side surface of the phosphor layer 12, it is possible to efficiently extract the fluorescent component emitted from the phosphor layer 12 to the outside. Further, in this structure, since the wavelength selective transmission / reflection layer 61 is provided on the incident surface side on which the excitation light is incident in the phosphor layer 12, the opposite side (rear side) of the phosphor layer 12 to the light extraction side. The fluorescent component that emits light is reflected at the interface between the phosphor layer 12 and the wavelength selective transmission / reflection layer 61, and can be effectively extracted to the outside as light emission on the light extraction side. That is, by providing the wavelength selective transmission / reflection layer 61 on the incident surface side of the phosphor layer 12 where the excitation light is incident, the fluorescent component emitted from the phosphor layer 12 can be extracted to the outside very efficiently. .

(5) Fifth Embodiment FIG. 7 is a schematic cross-sectional view showing a light emitting device according to a fifth embodiment. In FIG. 7, the same components as those of the light emitting device 30 shown in FIG.
The light-emitting device 70 includes an excitation light source 11 that emits excitation light, a substrate 13 that is disposed opposite to the excitation light source, and is formed with a phosphor layer 12 that is excited by the excitation light and emits fluorescence. At least the phosphor layer 12 along the stacking direction of the substrate 13 and the light distribution adjustment layer 31 that is formed between the phosphor layers 12 and changes the emission direction of at least fluorescence emitted from the phosphor layer. A light-reflective barrier 51 on one or more side surfaces, a wavelength selective transmission / reflection layer 61 formed on the incident surface side of the phosphor layer 12 on which excitation light is incident, the phosphor layer 12 and the wavelength selective transmission Between the reflective layers 61, a low refractive index layer 71 having a refractive index smaller than that of the phosphor layer 12 is schematically configured.

That is, the low refractive index layer 71 is provided between the phosphor layer 12 and the wavelength selective transmission / reflection layer 61, and out of the fluorescence emitted from the phosphor layer, the critical angle of the interface between the phosphor layer and the low refractive index layer is greater than the critical angle. And a layer having a feature of reflecting at least the fluorescence incident on the interface.
Of the fluorescence emitted isotropically in all directions from the phosphor layer 12, a fluorescent component directed to the back side of the light emitting device 70 is a low refractive index provided between the phosphor layer 12 and the wavelength selective transmission / reflection layer 61. The layer 71 can be efficiently reflected in the front direction, and the light emission efficiency can be improved.

Examples of the low refractive index layer 71 include a fluorine resin having a refractive index of about 1.35 to 1.4, a silicone resin having a refractive index of about 1.4 to 1.5, and a silica having a refractive index of about 1.003 to 1.3. Examples include airgel and transparent materials such as porous silica having a refractive index of about 1.2 to 1.3. However, the present embodiment is not limited to these materials.

The refractive index of the low refractive index layer 71 is preferably as low as possible. To lower the refractive index, the low refractive index layer 71 is made of silica airgel or porous material in order to have pores or voids in the low refractive index layer 71. Those formed of silica or the like are more preferable. Silica airgel is particularly preferred because it has a very low refractive index.

Silica airgel is disclosed in, for example, US Pat. No. 4,402,827, Japanese Patent Publication “Patent No. 4279971”, Japanese Published Patent Publication “JP-A 2001-202827” and the like. It is produced by drying a gel compound in a wet state comprising a silica skeleton obtained by a polymerization reaction in the presence of a solvent such as alcohol or carbon dioxide in a supercritical state above the critical point of the solvent.

The low refractive index layer 71 is preferably made of a gas. As described above, the refractive index of the low refractive index layer 71 is preferably as low as possible. However, when the low refractive index layer 71 is formed of a material such as a solid, liquid, or gel, US Pat. No. 4,402,827 and Japanese Patent Publication “ As described in Japanese Patent No. 4279971 ”, Japanese Patent Application Publication“ JP-A 2001-202827 ”and the like, the lower limit of the refractive index is about 1.003. On the other hand, if the low refractive index layer 16 is a gas layer made of a gas such as oxygen or nitrogen, for example, the refractive index can be set to 1.0, and the fluorescence is extracted to the outside very efficiently. It becomes possible.

With reference to FIG. 7, the light emission in the light-emitting device 70 is demonstrated.
In the light emitting device 70, when excitation light is incident on the phosphor layer 12 from the excitation light source 11, light is emitted from the phosphor layer 12 isotropically, that is, with equal energy in any direction. The luminance viewing angle characteristic of this light is such that the larger the viewing angle is, the larger the viewing angle is between 0 ° and 80 °, since the viewing angle (the angle formed by the surface perpendicular to the light emitting surface and the viewing direction) is related to the solid angle. Has a high profile. Then, this light enters the light distribution adjustment layer 31 and is scattered in the light distribution adjustment layer 31 to change the traveling direction of the light. At this time, the optical path length in the light distribution adjustment layer 31 is longer in the latter case between light incident perpendicularly to the surface of the light distribution adjustment layer 31 and light incident in an oblique direction.

Further, in this structure, since the low refractive index layer 71 is provided between the phosphor layer 12 and the wavelength selective transmission / reflection layer 61, the phosphor layer 12 is on the opposite side (back side) to the light extraction side. Among the fluorescent components that emit light, the fluorescent light incident on the interface is reflected at an angle greater than or equal to the critical angle of the interface between the phosphor layer and the low refractive index layer, and can be effectively extracted to the outside as light emission on the light extraction side. In general, the wavelength-selective transmission / reflection layer 61 has a feature that the reflectance of light incident at a shallow angle with respect to the incident surface is reduced. Therefore, when combined with the low refractive index layer 71, the wavelength selective transmission / reflection layer 61 is incident at a shallow angle. The reflected light can be reliably reflected and recycled. That is, by providing the low refractive index layer 71 between the phosphor layer 12 and the wavelength selective transmission / reflection layer 61, the fluorescent component emitted from the phosphor layer 12 can be extracted to the outside very efficiently.

(6) Sixth Embodiment FIG. 8 is a schematic cross-sectional view showing a light emitting device of a sixth embodiment. 8, the same components as those of the light emitting device 30 shown in FIG. 3 are denoted by the same reference numerals, and the description thereof is omitted.
The light-emitting device 80 includes an excitation light source 11 that emits excitation light, a substrate 13 that is disposed opposite to the excitation light source and on which a phosphor layer 12 that is excited by the excitation light and emits fluorescence is formed. At least the phosphor layer 12 along the stacking direction of the substrate 13 and the light distribution adjustment layer 31 that is formed between the phosphor layers 12 and changes the emission direction of at least fluorescence emitted from the phosphor layer. A light-reflective barrier 51 on one or more side surfaces, a wavelength selective transmission / reflection layer 61 formed on the phosphor layer 12 on the incident surface side on which excitation light is incident, the phosphor layer 12 and the wavelength selective transmission Between the reflective layer 61, the low refractive index layer 71 having a smaller refractive index than the phosphor layer 12, and between the light distribution layer 31 and the phosphor layer 12 refracted more than the phosphor layer 12. Such as a low refractive index layer 81 with a low refractive index. It is schematic configuration.

That is, the low refractive index layer 81 is provided between the light distribution adjusting layer 31 and the phosphor layer 12, and the critical angle at the interface between the phosphor layer 31 and the low refractive index layer 81 among the fluorescence emitted from the phosphor layer. As described above, by reflecting at least the fluorescence incident on the interface, it is incident on the substrate 13 from the phosphor layer 12 but cannot be taken out from the substrate. It is a layer characterized by suppressing the component which carries out.
Of the fluorescence emitted isotropically in all directions from the phosphor layer 12, a fluorescent component directed to the front side of the light emitting device 80 is a low refractive index provided between the light distribution control layer 31 and the phosphor layer 12. The layer 81 can be efficiently taken out, and the light emission efficiency can be improved.

With reference to FIG. 8, the light emission in the light-emitting device 80 is demonstrated.
In the light emitting device 70, when excitation light is incident on the phosphor layer 12 from the excitation light source 11, light is emitted from the phosphor layer 12 isotropically, that is, with equal energy in any direction. The luminance viewing angle characteristic of this light is such that the larger the viewing angle is, the larger the viewing angle is between 0 ° and 80 °, since the viewing angle (the angle formed by the surface perpendicular to the light emitting surface and the viewing direction) is related to the solid angle. Has a high profile. Then, this light enters the light distribution adjustment layer 31 and is scattered in the light distribution adjustment layer 31 to change the traveling direction of the light. At this time, the optical path length in the light distribution adjustment layer 31 is longer in the latter case between light incident perpendicularly to the surface of the light distribution adjustment layer 31 and light incident in an oblique direction. Therefore, the latter light with respect to the former is often scattered in the light distribution adjusting layer 31.

In other words, a light emission profile in which the luminance increases as the viewing angle increases is changed to a light emission profile in which at least the luminance in the 0 ° direction is equal to or higher than the luminance in the oblique direction through the light distribution adjustment layer 31. be able to. As a result, a light-emitting device that does not change in brightness when viewed from any direction can be obtained. Further, in this configuration, since the light-reflective barrier 51 is provided on the side surface of the phosphor layer 12, among the fluorescence emitted from the phosphor layer 12, the fluorescence component reflected at the interface of the substrate 13 and the fluorescence The fluorescent component that emits light on the side opposite to the light extraction side of the body layer 12 is reflected by the side surface of the light-reflective barrier 51 and recycled again to a component that can be extracted to the substrate 13 side. That is, by providing the light-reflective barrier 51 on the side surface of the phosphor layer 12, the fluorescent component emitted from the phosphor layer 12 can be efficiently extracted outside.

Further, in this structure, since the wavelength selective transmission / reflection layer 61 is provided on the incident surface side on which the excitation light is incident in the phosphor layer 12, the opposite side (rear side) of the phosphor layer 12 to the light extraction side. The fluorescent component that emits light is reflected at the interface between the phosphor layer 12 and the wavelength selective transmission / reflection layer 61, and can be effectively extracted to the outside as light emission on the light extraction side. That is, by providing the wavelength selective transmission / reflection layer 61 on the incident surface side of the phosphor layer 12 where the excitation light is incident, the fluorescent component emitted from the phosphor layer 12 can be extracted to the outside very efficiently. . Further, in this structure, since the low refractive index layer 71 is provided between the phosphor layer 12 and the wavelength selective transmission / reflection layer 61, the phosphor layer 12 is on the opposite side (back side) to the light extraction side. Among the fluorescent components that emit light, the fluorescent light incident on the interface is reflected at an angle greater than or equal to the critical angle of the interface between the phosphor layer and the low refractive index layer, and can be effectively extracted to the outside as light emission on the light extraction side.

In general, the wavelength-selective transmission / reflection layer 61 has a feature that the reflectance of light incident at a shallow angle with respect to the incident surface is reduced. Therefore, when combined with the low refractive index layer 71, the wavelength selective transmission / reflection layer 61 is incident at a shallow angle. The reflected light can be reliably reflected and recycled. That is, by providing the low refractive index layer 71 between the phosphor layer 12 and the wavelength selective transmission / reflection layer 61, the fluorescent component emitted from the phosphor layer 12 can be extracted to the outside very efficiently. Further, in this structure, since the low refractive index layer 81 is provided between the light distribution adjustment layer 31 and the phosphor layer 12, among the fluorescent components that emit light on the light extraction side of the phosphor layer 12, fluorescence By reflecting the fluorescence incident on the interface at a critical angle equal to or greater than the critical angle of the interface between the body layer 12 and the low refractive index layer 81, the fluorescence component emitted from the phosphor layer 31 at a shallow angle is prevented from entering the substrate. be able to. That is, it is possible to suppress a loss component that is incident on the substrate 13 but is reflected at the interface between the substrate 13 and the outside and cannot be extracted to the outside and is guided in the substrate 13. That is, by providing the low refractive index layer 81 between the light distribution adjustment layer 31 and the phosphor layer 12, the fluorescent component emitted from the phosphor layer 12 can be extracted outside without loss.

(7) Seventh Embodiment FIG. 9 is a schematic cross-sectional view showing a light emitting device according to a seventh embodiment. In FIG. 9, the same components as those of the light emitting device 30 shown in FIG.
The light-emitting device 90 includes an excitation light source 11 that emits excitation light, a first phosphor layer 91 that is arranged to face the excitation light source, emits fluorescence when excited by the excitation light, and a second phosphor layer 92. The substrate 13 on which the third phosphor layer 93 is formed, and the emission direction of the fluorescence emitted from at least the phosphor layers 91 to 93 formed between the substrate 13 and the phosphor layers 91 to 93. The light distribution adjusting layer 31 that changes the light intensity, the light-reflective barrier 51 formed on the substrate 13 between the phosphor layers adjacent to each other, and the incident surfaces on which the excitation light is incident on the phosphor layers 91 to 93 A wavelength selective transmission / reflection layer 61 formed on the side, and between the phosphor layers 91 to 93 and the wavelength selection transmission / reflection layer 61, a low refractive index layer 71 having a smaller refractive index than the phosphor layers 91 to 93. And the light distribution layer 31 and the fluorescence Between the layers 91-93 are schematic configuration of a small low-refractive index layer 81. refractive index than the phosphor layer 91-93.

With reference to FIG. 9, the light emission in the light-emitting device 90 is demonstrated.
In the light emitting device 90, when excitation light is incident on the first phosphor layer 91, the second phosphor layer 92, and the third phosphor layer 93 from the excitation light source 11, isotropic from each phosphor layer, that is, Light is emitted with equal energy in any direction. However, the light distribution profile of fluorescence extracted from the phosphor layer to the outside often differs depending on the type of phosphor. For example, when the refractive index of the phosphor material or resin material constituting the phosphor layer is different for each phosphor layer, the refraction angle at which the fluorescence extracted outside is refracted at the interface between the phosphor layer and the outside is the phosphor layer It depends on. That is, the light distribution profile of the fluorescence extracted to the outside is different for each phosphor layer. For example, when the phosphor layer is made of an inorganic phosphor material, the light emission characteristics vary depending on the particle size and shape of the phosphor particles.

That is, the light distribution profile of the fluorescence extracted outside is different for each phosphor layer. Fluorescent components emitted from the first fluorescent layer 91, fluorescent components emitted from the second fluorescent layer 92, and fluorescent components emitted from the third fluorescent layer 93, which have different emission profiles, enter the light distribution adjustment layer 31. Then, the incident fluorescence changes in the light distribution adjusting layer 31 due to light scattering. At this time, the optical path length in the light distribution adjustment layer 31 is longer in the latter case between light incident perpendicularly to the surface of the light distribution adjustment layer 31 and light incident in an oblique direction. Therefore, the latter light with respect to the former is often scattered in the light distribution adjusting layer 31. In other words, a light emission profile in which the luminance increases as the viewing angle increases has a light emission profile in which the luminance in at least 0 ° direction is equal to or higher than the luminance in the oblique direction through the light distribution adjustment layer 31. The fluorescent component is extracted to the outside as light emission 94 from the first phosphor layer 91, light emission 95 from the second phosphor layer 92, and light emission 96 from the third phosphor layer 93. As a result, it is possible to obtain a light emitting device that does not change in brightness when viewed from any direction and does not change color when viewed from any direction.

Further, in this configuration, since the light-reflective barrier 51 is provided between the phosphor layers adjacent to each other, among the fluorescence emitted from the phosphor layer, the fluorescence component reflected at the interface of the substrate 13 and The fluorescent component that emits light on the side opposite to the light extraction side of the phosphor layer is reflected by the side surface of the light-reflective barrier 51 and recycled again to a component that can be extracted to the substrate 13 side. That is, by providing the light-reflective barrier 51 between the phosphor layers adjacent to each other, the fluorescent component emitted from the phosphor layer can be efficiently extracted to the outside. Further, in this structure, since the wavelength selective transmission / reflection layer 61 is provided on the incident surface side on which the excitation light is incident in the phosphor layer, light is emitted on the opposite side (back side) of the phosphor layer to the light extraction side. The fluorescent component to be reflected is reflected at the interface between the phosphor layer and the wavelength selective transmission / reflection layer 61 and can be effectively extracted to the outside as light emission on the light extraction side. That is, by providing the wavelength selective transmission / reflection layer 61 on the side of the phosphor layer where the excitation light is incident, the fluorescent component emitted from the phosphor layer can be extracted to the outside very efficiently.

Further, in this structure, since the low refractive index layer 71 is provided between the phosphor layers 91 to 93 and the wavelength selective transmission / reflection layer 61, the side opposite to the light extraction side of the phosphor layers 91 to 93 ( Of the fluorescent components emitted on the back side), the fluorescent light incident on the interface is reflected at an angle greater than the critical angle of the interface between the phosphor layer and the low refractive index layer, and is effectively extracted to the outside as light emission on the light extraction side. Can do. In general, the wavelength-selective transmission / reflection layer 61 has a feature that the reflectance of light incident at a shallow angle with respect to the incident surface is reduced. Therefore, when combined with the low refractive index layer 71, the wavelength selective transmission / reflection layer 61 is incident at a shallow angle. The reflected light can be reliably reflected and recycled. That is, by providing the low refractive index layer 71 between the phosphor layers 91 to 93 and the wavelength selective transmission / reflection layer 61, the fluorescent components emitted from the phosphor layers 91 to 93 can be taken out very efficiently to the outside. It becomes possible.

In this structure, since the low refractive index layer 81 is provided between the light distribution adjusting layer 31 and the phosphor layers 91 to 93, the fluorescent component that emits light to the light extraction side of the phosphor layers 91 to 93 is provided. Among them, by reflecting the fluorescence incident on the interface at a critical angle greater than the critical angle of the interface between the phosphor layer and the low refractive index layer, it is possible to suppress the fluorescence component emitted at a shallow angle from the phosphor layer from entering the substrate. can do. That is, although it is incident on the substrate, it is reflected at the interface between the substrate and the outside and cannot be taken out to the outside, and a loss component that is guided in the substrate can be suppressed. That is, by providing the low refractive index layer 81 between the light distribution adjustment layer 31 and the phosphor layers 91 to 93, the fluorescent component emitted from the phosphor layers 91 to 93 can be extracted outside without loss. Become.

(8) Eighth Embodiment FIG. 10 is a schematic cross-sectional view showing a light emitting device according to an eighth embodiment. In FIG. 10, the same components as those of the light emitting device 30 shown in FIG.
The light-emitting device 100 includes an excitation light source 11 that emits excitation light, a first phosphor layer 91 that is disposed opposite to the excitation light source, emits fluorescence when excited by the excitation light, and a second phosphor layer 92. The emission direction of fluorescence emitted from at least the phosphor layers 91 to 93 formed between the substrate 13 on which the third phosphor layer 93 is formed, and the substrate 13 and the phosphor layers 91 to 93. The light distribution adjusting layer 31 for changing the light intensity, the light-reflective barrier 51 formed on the substrate 13 between the phosphor layers adjacent to each other, and the incident surfaces on which the excitation light is incident on the phosphor layers 91 to 93 The wavelength selective transmission / reflection layer 61 formed on the side, and the low refractive index layer 71 having a smaller refractive index than the phosphor layers 91 to 93 between the phosphor layers 91 to 93 and the wavelength selective transmission / reflection layer 61. The light distribution layer 31 and the firefly Between the body layers 91 to 93, a low refractive index layer 81 having a refractive index smaller than that of the phosphor layers 91 to 93 is roughly configured. The light distribution adjusting layer 31 includes the barrier 51 and the substrate 13. It is formed so as to spread upward.

With reference to FIG. 10, the light emission in the light-emitting device 100 is demonstrated.
In the light emitting device 100, when excitation light is incident on the first phosphor layer 91, the second phosphor layer 92, and the third phosphor layer 93 from the excitation light source 11, isotropic from each phosphor layer, that is, Light is emitted with equal energy in any direction. However, the light distribution profile of fluorescence extracted from the phosphor layer to the outside often differs depending on the type of phosphor. For example, when the refractive index of the phosphor material or resin material constituting the phosphor layer is different for each phosphor layer, the refraction angle at which the fluorescence extracted outside is refracted at the interface between the phosphor layer and the outside is the phosphor layer It depends on. That is, the light distribution profile of the fluorescence extracted to the outside is different for each phosphor layer. For example, when the phosphor layer is made of an inorganic phosphor material, the light emission characteristics vary depending on the particle size and shape of the phosphor particles.

Further, in this structure, since the low refractive index layer 71 is provided between the phosphor layers 91 to 93 and the wavelength selective transmission / reflection layer 61, the side opposite to the light extraction side of the phosphor layers 91 to 93 ( Of the fluorescent components emitted on the back side), the fluorescent light incident on the interface is reflected at an angle greater than the critical angle of the interface between the phosphor layer and the low refractive index layer, and is effectively extracted to the outside as light emission on the light extraction side. Can do. In general, the wavelength-selective transmission / reflection layer 61 has a feature that the reflectance of light incident at a shallow angle with respect to the incident surface is reduced. Therefore, when combined with the low refractive index layer 71, the wavelength selective transmission / reflection layer 61 is incident at a shallow angle. The reflected light can be reliably reflected and recycled.

That is, by providing the low refractive index layer 71 between the phosphor layers 91 to 93 and the wavelength selective transmission / reflection layer 61, the fluorescent components emitted from the phosphor layers 91 to 93 can be taken out very efficiently to the outside. It becomes possible. In this structure, since the low refractive index layer 81 is provided between the light distribution adjusting layer 31 and the phosphor layers 91 to 93, the fluorescent component that emits light to the light extraction side of the phosphor layers 91 to 93 is provided. Among them, by reflecting the fluorescence incident on the interface at a critical angle greater than the critical angle of the interface between the phosphor layer and the low refractive index layer, it is possible to suppress the fluorescence component emitted at a shallow angle from the phosphor layer from entering the substrate. can do. That is, although it is incident on the substrate, it is reflected at the interface between the substrate and the outside and cannot be taken out to the outside, and a loss component that is guided in the substrate can be suppressed. That is, by providing the low refractive index layer 81 between the light distribution adjustment layer 31 and the phosphor layers 91 to 93, the fluorescent component emitted from the phosphor layers 91 to 93 can be extracted outside without loss. Become.

Further, in this structure, since the light distribution adjusting layer 31 is formed between the barrier layers 51 on the side surfaces of the phosphor layers 91 to 93, the phosphor layers 91 to 93 laterally extend from the phosphor layers 91 to 93. Before the emitted fluorescent component enters the barrier 51, a part of the fluorescent component can be backscattered (reflected) by the light distribution adjusting layer 31. In other words, the reflecting ability of the barrier can be enhanced through the light distribution adjusting layer 13, and light incident on the barrier 51 can be prevented from passing through the barrier 51 and entering an adjacent pixel. it can. In addition, since the light distribution adjustment layer is partitioned by a barrier when viewed from the light extraction direction, it is possible to prevent light from entering the adjacent pixels through the light distribution adjustment layer.

(9) Ninth Embodiment FIG. 11 is a schematic sectional view showing a light emitting device according to the ninth embodiment. In FIG. 11, the same components as those of the light emitting device 30 shown in FIG.
The light-emitting device 110 includes an excitation light source 11 that emits excitation light, a first phosphor layer 91 that is arranged to face the excitation light source, emits fluorescence when excited by the excitation light, and a second phosphor layer 92. The emission direction of the fluorescence emitted from at least the phosphor layer 91 formed between the substrate 13 on which the third phosphor layer 93 is formed, the substrate 13 and the first phosphor layer 91; A light distribution adjustment layer 112 which is formed between the light distribution adjustment layer 111 to be changed and the second phosphor layer 92 and which changes the emission direction of at least the fluorescence emitted from the phosphor layer 92, and a third phosphor Formed on the substrate 13 between at least the light distribution adjusting layer 113 that changes the emission direction of the fluorescence emitted from the phosphor layer 93 and between the phosphor layers adjacent to each other. Light-reflective barrier 51 and fluorescence In the layers 91 to 93, the wavelength selective transmission / reflection layer 61 formed on the incident surface side on which excitation light is incident, and between the phosphor layers 91 to 93 and the wavelength selective transmission / reflection layer 61, the phosphor layer 91 Low refractive index layer 71 having a refractive index smaller than that of 93, and between the light distribution control layers 111 to 113 and the phosphor layers 91 to 93, a low refractive index having a refractive index lower than that of the phosphor layers 91 to 93. The refractive index layer 81 is generally configured.

With reference to FIG. 11, the light emission in the light-emitting device 110 is demonstrated.
In the light emitting device 110, when excitation light is incident on the first phosphor layer 91, the second phosphor layer 92, and the third phosphor layer 93 from the excitation light source 11, isotropic from each phosphor layer, that is, Light is emitted with equal energy in any direction. However, the light distribution profile of fluorescence extracted from the phosphor layer to the outside often differs depending on the type of phosphor. For example, when the refractive index of the phosphor material or resin material constituting the phosphor layer is different for each phosphor layer, the refraction angle at which the fluorescence extracted outside is refracted at the interface between the phosphor layer and the outside is the phosphor layer It depends on. That is, the light distribution profile of the fluorescence extracted to the outside is different for each phosphor layer. For example, when the phosphor layer is made of an inorganic phosphor material, the light emission characteristics vary depending on the particle size and shape of the phosphor particles.

That is, the light distribution profile of the fluorescence extracted outside is different for each phosphor layer. The light emission profiles are different from each other, the fluorescent component emitted from the first fluorescent layer 91, the fluorescent component emitted from the second fluorescent layer 92, and the fluorescent component emitted from the third fluorescent layer 93, respectively. When the light enters the light distribution adjusting layer 112 and the light distribution adjusting layer 113, the incident fluorescence changes in the light traveling direction in the light distribution adjusting layer due to light scattering. At this time, the light path length in the light distribution adjustment layer is longer in the latter case between light incident perpendicularly to the surface of the light distribution adjustment layer and light incident in an oblique direction. Therefore, the latter light with respect to the former is often scattered in the light distribution adjusting layer. In other words, the fluorescence having a light emission profile in which the luminance is higher as the viewing angle is larger, and the luminance in at least 0 ° direction is equal to or higher than the luminance in the oblique direction through the light distribution adjustment layer. The components are extracted to the outside as light emission 94 from the first phosphor layer 91, light emission 95 from the second phosphor layer 92, and light emission 96 from the third phosphor layer 93. As a result, it is possible to obtain a light emitting device that does not change in brightness when viewed from any direction and does not change color when viewed from any direction.

In this structure, since the low refractive index layer 71 is provided between the phosphor layer and the wavelength selective transmission / reflection layer 61, light is emitted from the phosphor layer opposite to the light extraction side (back side). Among the fluorescent components, the fluorescent light incident on the interface is reflected at an angle greater than or equal to the critical angle of the interface between the phosphor layer and the low refractive index layer, and can be effectively extracted to the outside as light emission on the light extraction side. In general, the wavelength-selective transmission / reflection layer 61 has a feature that the reflectance of light incident at a shallow angle with respect to the incident surface is reduced. Therefore, when combined with the low refractive index layer 71, the wavelength selective transmission / reflection layer 61 is incident at a shallow angle. The reflected light can be reliably reflected and recycled. That is, by providing the low refractive index layer 71 between the phosphor layers 91 to 93 and the wavelength selective transmission / reflection layer 61, the fluorescent component emitted from the phosphor layer can be extracted to the outside very efficiently. .

In this structure, since the low refractive index layer 81 is provided between the light distribution adjusting layers 111 to 113 and the phosphor layers 91 to 93, light is emitted to the light extraction side of the phosphor layers 91 to 93. Among the fluorescent components, the fluorescent component emitted at a shallow angle from the phosphor layer is incident on the substrate by reflecting the fluorescence incident on the interface at a critical angle greater than the critical angle of the interface between the phosphor layer and the low refractive index layer. Can be suppressed. That is, although it is incident on the substrate, it is reflected at the interface between the substrate and the outside and cannot be taken out to the outside, and a loss component that is guided in the substrate can be suppressed. That is, by providing the low refractive index layer 81 between the light distribution adjustment layer 31 and the phosphor layers 91 to 93, the fluorescent component emitted from the phosphor layers 91 to 93 can be extracted outside without loss. Become. In addition, in this structure, the light distribution adjustment layer is partitioned by a barrier when viewed from the light extraction direction, so that light can be prevented from entering the adjacent pixels by being guided through the light distribution adjustment layer. .

It is preferable to optimize the particle size of the light scatterer material of the light distribution adjusting layer according to the wavelength of the fluorescence emitted from the phosphor layer.

Generally, the scattering intensity parameter that determines the scattering characteristics of a particle is the difference between the refractive index of the particle and the refractive index of the environment surrounding the particle, the particle size parameter α (α = πD / λ [D: particle diameter of the particle). , Λ: wavelength of light]), and a scattering angle θ (an angle formed by incident light incident on the particle and scattered light scattered by the particle). Among these, the particle size parameter α greatly affects the scattering characteristics. When α <1, the scattering intensity distribution is dominated by forward scattering (around θ = 0 °) and backward scattering (around θ = 180 °), and hardly scatters to the side (around θ = 90 °). This is a so-called Rayleigh scattering region. Further, in the case of α≈1, forward scattering and side scattering are dominant, and a so-called Mie scattering region in which little scattering occurs in the back is obtained.

Further, in the case of α >> 1, forward scattering is dominant, and it becomes a diffraction scattering region based on so-called geometrical optics that hardly scatters to the side and back. That is, the particle size parameter α is determined by the particle size of the particle and the wavelength of light incident on the particle, that is, the wavelength of fluorescence emitted from the phosphor layer. For example, when it is desired to scatter 600 nm fluorescence forward and laterally by the light distribution adjusting layer, the particle size of the particles may be set so that the particle size parameter α≈1.

(10) Tenth Embodiment FIG. 12 is a schematic sectional view showing a light emitting device according to the tenth embodiment. In FIG. 12, the same components as those of the light emitting device 30 shown in FIG.
The light emitting device 120 includes an excitation light source 11 that emits excitation light, a first phosphor layer 91 that is disposed to face the excitation light source, and that emits fluorescence when excited by the excitation light, and a second phosphor layer 92. The substrate 13 on which the third phosphor layer 93 is formed, and the emission direction of the fluorescence emitted from at least the phosphor layers 91 to 93 formed between the substrate 13 and the phosphor layers 91 to 93. The light distribution adjusting layer 31 that changes the light intensity, the light-reflective barrier 51 formed on the substrate 13 between the phosphor layers adjacent to each other, and the incident surfaces on which the excitation light is incident on the phosphor layers 91 to 93 A wavelength selective transmission / reflection layer 61 formed on the side, and between the phosphor layers 91 to 93 and the wavelength selection transmission / reflection layer 61, a low refractive index layer 71 having a smaller refractive index than the phosphor layers 91 to 93. The light distribution layer 31 and the firefly A low refractive index layer 81 having a refractive index smaller than that of the phosphor layers 91 to 93 and a light absorption layer 121 formed between the light distribution adjusting layer 31 and the barrier 51, respectively, between the body layers 91 to 93. It is roughly composed.

The light absorption layer 121 is made of a light-absorbing material, and is formed corresponding to a region between adjacent pixels. The light absorption layer 121 can improve display contrast.
The film thickness of the light absorption layer 121 is usually about 100 nm to 100 μm, preferably 100 nm to 10 μm. Further, in order to efficiently extract light emitted from the side surface of the phosphor layer 13 to the outside, it is preferable that the thickness of the light absorption layer 121 is smaller than the thickness of the phosphor layers 91 to 93.

With reference to FIG. 12, the light emission in the light-emitting device 120 is demonstrated.
In the light emitting device 120, when excitation light is incident on the first phosphor layer 91, the second phosphor layer 92, and the third phosphor layer 93 from the excitation light source 11, isotropic from each phosphor layer, that is, Light is emitted with equal energy in any direction. However, the light distribution profile of fluorescence extracted from the phosphor layer to the outside often differs depending on the type of phosphor. For example, when the refractive index of the phosphor material or resin material constituting the phosphor layer is different for each phosphor layer, the refraction angle at which the fluorescence extracted outside is refracted at the interface between the phosphor layer and the outside is the phosphor layer It depends on. That is, the light distribution profile of the fluorescence extracted to the outside is different for each phosphor layer. For example, when the phosphor layer is made of an inorganic phosphor material, the light emission characteristics vary depending on the particle size and shape of the phosphor particles.

In this configuration, since the light absorption layer 121 formed between the light distribution adjusting layer 31 and the barrier 51 is provided between the phosphor layers adjacent to each other, the phosphor layer 91 is provided. It is possible to prevent the fluorescence emitted from .about.93 from entering the adjacent phosphor layer by light absorption, and the display contrast can be improved.

(11) Eleventh Embodiment FIG. 13 is a schematic sectional view showing a light emitting device according to the eleventh embodiment. In FIG. 11, the same components as those of the light emitting device 30 shown in FIG.
The light-emitting device 130 includes an excitation light source 11 that emits excitation light, a first phosphor layer 91 that is disposed to face the excitation light source, emits fluorescence when excited by the excitation light, and a second phosphor layer 92. The emission direction of the fluorescence emitted from at least the phosphor layer 91 formed between the substrate 13 on which the third phosphor layer 93 is formed, the substrate 13 and the first phosphor layer 91 is defined. A light distribution adjustment layer 112 that is formed between the light distribution adjustment layer 111 to be changed and the second phosphor layer 92 and changes the emission direction of at least the fluorescence emitted from the phosphor layer 92, and a third phosphor. Formed on the substrate 13 between at least the light distribution adjusting layer 113 that changes the emission direction of the fluorescence emitted from the phosphor layer 93 and between the phosphor layers adjacent to each other. Light-reflective barrier 51 and fluorescence In the layers 91 to 93, the wavelength selective transmission / reflection layer 61 formed on the incident surface side on which excitation light is incident, and between the phosphor layers 91 to 93 and the wavelength selective transmission / reflection layer 61, the phosphor layer 91 Low refractive index layer 71 having a refractive index smaller than that of 93, and between the light distribution control layers 111 to 113 and the phosphor layers 91 to 93, a low refractive index having a refractive index lower than that of the phosphor layers 91 to 93. A light absorbing layer 121 is formed between the refractive index layer 81 and the light distribution adjusting layers 111 to 113 adjacent to each other and between the substrate 13 and the barrier 51, respectively.

With reference to FIG. 13, the light emission in the light-emitting device 130 is demonstrated.
In the light emitting device 130, when excitation light is incident on the first phosphor layer 91, the second phosphor layer 92, and the third phosphor layer 93 from the excitation light source 11, isotropic from each phosphor layer, that is, Light is emitted with equal energy in any direction. However, the light distribution profile of fluorescence extracted from the phosphor layer to the outside often differs depending on the type of phosphor. For example, when the refractive index of the phosphor material or resin material constituting the phosphor layer is different for each phosphor layer, the refraction angle at which the fluorescence extracted outside is refracted at the interface between the phosphor layer and the outside is the phosphor layer It depends on. That is, the light distribution profile of the fluorescence extracted to the outside is different for each phosphor layer. For example, when the phosphor layer is made of an inorganic phosphor material, the light emission characteristics vary depending on the particle size and shape of the phosphor particles.

In this structure, since the low refractive index layer 81 is provided between the light distribution adjusting layer 31 and the phosphor layers 91 to 93, the fluorescent component that emits light to the light extraction side of the phosphor layers 91 to 93 is provided. Among them, by reflecting the fluorescence incident on the interface at a critical angle greater than the critical angle of the interface between the phosphor layer and the low refractive index layer, it is possible to suppress the fluorescence component emitted at a shallow angle from the phosphor layer from entering the substrate. can do. That is, although it is incident on the substrate, it is reflected at the interface between the substrate and the outside and cannot be taken out to the outside, and a loss component that is guided in the substrate can be suppressed. That is, by providing the low refractive index layer 81 between the light distribution adjustment layers 111 to 113 and the phosphor layers 91 to 93, the fluorescent components emitted from the phosphor layers 91 to 93 can be taken out without loss. It becomes possible.

Further, in this structure, since the light distribution adjustment layer is partitioned by the light absorption layer as viewed from the light extraction direction, the light distribution adjustment layer is guided to prevent light from entering the adjacent pixels. You can also. In this configuration, since the light absorption layers 121 formed between the barrier 51 and the substrate 13 are provided between the light distribution adjustment layers adjacent to each other, the phosphor layers 91 to 93 are provided. It is possible to prevent the fluorescence emitted from the light from entering the adjacent phosphor layer by light absorption, and the display contrast can be improved.

Generally, the scattering intensity parameter that determines the scattering characteristics of a particle is the difference between the refractive index of the particle and the refractive index of the environment surrounding the particle, the particle size parameter α (α = πD / λ [D: particle diameter of the particle). , Λ: wavelength of light]), and a scattering angle θ (an angle formed by incident light incident on the particle and scattered light scattered by the particle). Among these, the particle size parameter α greatly affects the scattering characteristics. When α <1, the scattering intensity distribution is dominated by forward scattering (around θ = 0 °) and backward scattering (around θ = 180 °), and hardly scatters to the side (around θ = 90 °). This is a so-called Rayleigh scattering region.

Further, in the case of α≈1, forward scattering and side scattering are dominant, and a so-called Mie scattering region in which little scattering occurs in the backward direction. Further, in the case of α >> 1, forward scattering is dominant, and this is a diffraction scattering region based on so-called geometrical optics that hardly scatters to the side and back. That is, the particle size parameter α is determined by the particle size of the particle and the wavelength of light incident on the particle, that is, the wavelength of fluorescence emitted from the phosphor layer. For example, when it is desired to scatter 600 nm fluorescence forward and laterally by the light distribution adjusting layer, the particle size of the particles may be set so that the particle size parameter α≈1.

(12) Tenth Embodiment FIG. 14 is a schematic cross-sectional view showing a light emitting device according to the tenth embodiment. In FIG. 14, the same components as those of the light emitting device 30 shown in FIG.
The light-emitting device 140 includes an excitation light source 11 that emits excitation light, a first phosphor layer 91 that is arranged to face the excitation light source and that is excited by the excitation light to emit fluorescence, and a second phosphor layer 92. The emission direction of the fluorescence emitted from at least the phosphor layer 91 formed between the substrate 13 on which the third phosphor layer 93 is formed, the substrate 13 and the first phosphor layer 91 is defined. A light distribution adjustment layer 112 that is formed between the light distribution adjustment layer 111 to be changed and the second phosphor layer 92 and changes the emission direction of at least the fluorescence emitted from the phosphor layer 92, and a third phosphor. Formed on the substrate 13 between at least the light distribution adjusting layer 113 that changes the emission direction of the fluorescence emitted from the phosphor layer 93 and between the phosphor layers adjacent to each other. Light-reflective barrier 51 and fluorescence In the layers 91 to 93, the wavelength selective transmission / reflection layer 61 formed on the incident surface side on which excitation light is incident, and between the phosphor layers 91 to 93 and the wavelength selective transmission / reflection layer 61, the phosphor layer 91 Low refractive index layer 71 having a refractive index smaller than that of 93, and light distribution control layers 111 to 113 and phosphor layers 91 to 93 having a refractive index lower than that of phosphor layers 91 to 93. Between the refractive index layer 81 and the light distribution adjustment layers 111 to 113 adjacent to each other, a light absorption layer 121 formed between the substrate 13 and the barrier 51, and an excitation light incident surface of the barrier 51 The second light absorption layer 141 is formed roughly.

With reference to FIG. 14, the light emission in the light-emitting device 140 is demonstrated.
In the light emitting device 140, when excitation light is incident on the first phosphor layer 91, the second phosphor layer 92, and the third phosphor layer 93 from the excitation light source 11, isotropic from each phosphor layer, that is, Light is emitted with equal energy in any direction. However, the light distribution profile of fluorescence extracted from the phosphor layer to the outside often differs depending on the type of phosphor. For example, when the refractive index of the phosphor material or resin material constituting the phosphor layer is different for each phosphor layer, the refraction angle at which the fluorescence extracted outside is refracted at the interface between the phosphor layer and the outside is the phosphor layer It depends on. That is, the light distribution profile of the fluorescence extracted to the outside is different for each phosphor layer. For example, when the phosphor layer is made of an inorganic phosphor material, the light emission characteristics vary depending on the particle size and shape of the phosphor particles.

Further, in this configuration, since the light-reflective barrier 51 is provided between the phosphor layers adjacent to each other, among the fluorescence emitted from the phosphor layer, the fluorescence component reflected at the interface of the substrate 13 and The fluorescent component that emits light on the side opposite to the light extraction side of the phosphor layer is reflected by the side surface of the light-reflective barrier 51 and recycled again to a component that can be extracted to the substrate 13 side. That is, by providing the light-reflective barrier 51 between the phosphor layers adjacent to each other, the fluorescent component emitted from the phosphor layer can be efficiently extracted to the outside.

Further, in this structure, since the wavelength selective transmission / reflection layer 61 is provided on the incident surface side on which the excitation light is incident in the phosphor layer, light is emitted on the opposite side (back side) of the phosphor layer to the light extraction side. The fluorescent component to be reflected is reflected at the interface between the phosphor layer and the wavelength selective transmission / reflection layer 61 and can be effectively extracted to the outside as light emission on the light extraction side. That is, by providing the wavelength selective transmission / reflection layer 61 on the side of the phosphor layer where the excitation light is incident, the fluorescent component emitted from the phosphor layer can be extracted to the outside very efficiently.

In this structure, since the low refractive index layer 81 is provided between the light distribution adjusting layers 111 to 113 and the phosphor layers 91 to 93, light is emitted to the light extraction side of the phosphor layers 91 to 93. Among the fluorescent components, the fluorescent component emitted at a shallow angle from the phosphor layer is incident on the substrate by reflecting the fluorescence incident on the interface at a critical angle greater than the critical angle of the interface between the phosphor layer and the low refractive index layer. Can be suppressed. That is, although it is incident on the substrate, it is reflected at the interface between the substrate and the outside and cannot be taken out to the outside, and a loss component that is guided in the substrate can be suppressed. That is, by providing the low refractive index layer 81 between the light distribution adjustment layer 31 and the phosphor layers 91 to 93, the fluorescent component emitted from the phosphor layers 91 to 93 can be extracted outside without loss. Become.

Further, in this configuration, since the second light absorption layer 141 formed on the excitation light incident surface of the barrier 51 is provided, the excitation light does not enter the phosphor layer and hits the bottom surface of the barrier 51 and is reflected. Thus, it is possible to prevent the penetration of the adjacent phosphor layers by light absorption, and it is possible to prevent the display contrast from being lowered.

Generally, the scattering intensity parameter that determines the scattering characteristics of a particle is the difference between the refractive index of the particle and the refractive index of the environment surrounding the particle, the particle size parameter α (α = πD / λ [D: particle diameter of the particle). , Λ: wavelength of light]), and a scattering angle θ (an angle formed by incident light incident on the particle and scattered light scattered by the particle). Among these, the particle size parameter α greatly affects the scattering characteristics. When α <1, the scattering intensity distribution is dominated by forward scattering (around θ = 0 °) and backward scattering (around θ = 180 °), and hardly scatters to the side (around θ = 90 °). This is a so-called Rayleigh scattering region. Further, in the case of α≈1, forward scattering and side scattering are dominant, and a so-called Mie scattering region in which little scattering occurs in the back is obtained. Further, in the case of α >> 1, forward scattering is dominant, and it becomes a region of diffraction scattering based on so-called geometrical optics that hardly scatters to the side and back. That is, the particle size parameter α is determined by the particle size of the particle and the wavelength of light incident on the particle, that is, the wavelength of fluorescence emitted from the phosphor layer. For example, when it is desired to scatter 600 nm fluorescence forward and laterally by the light distribution adjusting layer, the particle size of the particles may be set so that the particle size parameter α≈1.

(13) Thirteenth Embodiment FIG. 15 is a schematic sectional view showing a light emitting device according to the thirteenth embodiment. In FIG. 15, the same components as those of the light emitting device 30 shown in FIG.
The light-emitting device 150 includes an excitation light source 11 that emits excitation light, a first phosphor layer 91 that is disposed opposite to the excitation light source, emits fluorescence when excited by the excitation light, and a second phosphor layer 92. The emission direction of the fluorescence emitted from at least the phosphor layer 91 formed between the substrate 13 on which the third phosphor layer 93 is formed, the substrate 13 and the first phosphor layer 91 is defined. A light distribution adjustment layer 112 that is formed between the light distribution adjustment layer 111 to be changed and the second phosphor layer 92 and changes the emission direction of at least the fluorescence emitted from the phosphor layer 92, and a third phosphor. Formed on the substrate 13 between at least the light distribution adjusting layer 113 that changes the emission direction of the fluorescence emitted from the phosphor layer 93 and between the phosphor layers adjacent to each other. Light-reflective barrier 51 and fluorescence In the layers 91 to 93, the wavelength selective transmission / reflection layer 61 formed on the incident surface side on which excitation light is incident, and between the phosphor layers 91 to 93 and the wavelength selective transmission / reflection layer 61, the phosphor layer 91 Low refractive index layer 71 having a refractive index smaller than that of 93, and light distribution control layers 111 to 113 and phosphor layers 91 to 93 having a refractive index lower than that of phosphor layers 91 to 93. Between the refractive index layer 81 and the light distribution adjustment layers 111 to 113 adjacent to each other, a light absorption layer 121 formed between the substrate 13 and the barrier 51, and an excitation light incident surface of the barrier 51 Of the second light absorption layer 141 formed on the substrate, the substrate 13, the first color filter 151 formed between the first light distribution control layer 111, and the second light distribution adjustment layer 112. A second color filter 152 formed therebetween; It is schematically composed of a third color filter 153 formed between the third light distribution control layer 113.

A conventional color filter can be used as the color filter. By providing the color filter, the color purity of the fluorescence emitted from the phosphor layer can be increased, and the color reproduction range can be expanded. In addition, the color filter provided in each phosphor layer absorbs the excitation light component contained in the external light, so it is possible to reduce or prevent the phosphor layer from emitting light due to the external light, reducing the decrease in contrast Or it can be prevented.

With reference to FIG. 15, the light emission in the light-emitting device 150 is demonstrated.
In the light emitting device 150, when excitation light is incident on the first phosphor layer 91, the second phosphor layer 92, and the third phosphor layer 93 from the excitation light source 11, isotropic from each phosphor layer, that is, Light is emitted with equal energy in any direction. However, the light distribution profile of fluorescence extracted from the phosphor layer to the outside often differs depending on the type of phosphor. For example, when the refractive index of the phosphor material or resin material constituting the phosphor layer is different for each phosphor layer, the refraction angle at which the fluorescence extracted outside is refracted at the interface between the phosphor layer and the outside is the phosphor layer It depends on. That is, the light distribution profile of the fluorescence extracted to the outside is different for each phosphor layer. For example, when the phosphor layer is made of an inorganic phosphor material, the light emission characteristics vary depending on the particle size and shape of the phosphor particles.

Further, in this configuration, since the second light absorption layer 141 formed on the excitation light incident surface of the barrier 51 is provided, the excitation light does not enter the phosphor layer and hits the bottom surface of the barrier 51 and is reflected. Thus, it is possible to prevent the penetration of the adjacent phosphor layers by light absorption, and it is possible to prevent the display contrast from being lowered. Further, in the present configuration, the second color formed between the substrate 13, the first color filter 151 formed between the first light distribution control layer 111 and the second light distribution adjustment layer 112. Since the third color filter 153 formed between the color filter 152 and the third light distribution adjustment layer 113 is provided, the color purity of the fluorescence emitted from each phosphor layer can be increased. The color reproduction range can be expanded.

In addition, since the color filter formed on each phosphor layer absorbs the excitation light component contained in the external light, it is possible to reduce or prevent light emission of the phosphor layer due to the external light, resulting in a decrease in contrast. Can be reduced or prevented. Furthermore, since it is possible to prevent the excitation light that is not absorbed by the phosphor layer from leaking to the outside, it is possible to prevent the color purity from being deteriorated due to color mixture by light emission from the phosphor layer and the excitation light. it can.

In the case of α≈1, forward scattering and side scattering are dominant, and so-called Mie scattering region is formed in which little scattering is performed backward. Further, in the case of α >> 1, forward scattering is dominant, and it becomes a region of diffraction scattering based on so-called geometrical optics that hardly scatters to the side and back. That is, the particle size parameter α is determined by the particle size of the particle and the wavelength of light incident on the particle, that is, the wavelength of fluorescence emitted from the phosphor layer. For example, when it is desired to scatter 600 nm fluorescence forward and laterally by the light distribution adjusting layer, the particle size of the particles may be set so that the particle size parameter α≈1.

(14) Fourteenth Embodiment FIG. 16 is a schematic cross-sectional view showing a light emitting device according to a fourteenth embodiment. In FIG. 16, the same components as those of the light emitting device 30 shown in FIG.
The light-emitting device 160 includes an excitation light source 11 that emits excitation light, a first phosphor layer 91 that is disposed to face the excitation light source, emits fluorescence when excited by the excitation light, and a second phosphor layer 92. , At least the phosphor formed between the substrate 13 on which the light distribution adjusting layer 161 for changing the light emission direction of the light emitted from the light source is formed, and the substrate 13 and the first phosphor layer 91. A light distribution adjusting layer 111 that changes the emission direction of the fluorescence emitted from the layer 91 and a distribution that changes the emission direction of the fluorescence emitted from at least the phosphor layer 92 formed between the second phosphor layer 92. A light-reflective barrier 51 formed on the substrate 13 between the light adjustment layer 112 and the phosphor layers 91 to 92 adjacent to each other or the light distribution control layer 161, and the phosphor layers 91 to 92, respectively. And light distribution adjustment layer 1 1, the wavelength selective transmission / reflection layer 61 formed on the incident surface side on which excitation light is incident, the phosphor layers 91 to 92, the light distribution adjustment layer 161, and the wavelength selective transmission / reflection layer 61, A low refractive index layer 71 having a lower refractive index than the body layers 91 to 92, between the light distribution control layers 111 to 112 and the phosphor layers 91 to 92, and between the light distribution adjustment layer 161 and the color filter 153. Between the low refractive index layer 81 having a smaller refractive index than the phosphor layers 91 to 92 and the light distribution adjusting layers 111 to 112 and 161 adjacent to each other, between the substrate 13 and the barrier 51. Formed between the light absorption layer 121 formed respectively, the second light absorption layer 141 formed on the excitation light incident surface of the barrier 51, the substrate 13, and the first light distribution adjusting layer 111. First color filter 15 And a second color filter 152 formed between the second light distribution adjustment layers 112 and a third color filter 153 formed between the third light distribution adjustment layers 161. .

With reference to FIG. 16, the light emission in the light-emitting device 160 is demonstrated.
In the light emitting device 160, when excitation light is incident on the first phosphor layer 91 and the second phosphor layer 92 from the excitation light source 11, they are isotropic from each phosphor layer, that is, with equal energy in any direction. The light is emitted. However, the light distribution profile of fluorescence extracted from the phosphor layer to the outside often differs depending on the type of phosphor. For example, when the refractive index of the phosphor material or resin material constituting the phosphor layer is different for each phosphor layer, the refraction angle at which the fluorescence extracted outside is refracted at the interface between the phosphor layer and the outside is the phosphor layer It depends on. That is, the light distribution profile of the fluorescence extracted to the outside is different for each phosphor layer. For example, when the phosphor layer is made of an inorganic phosphor material, the light emission characteristics vary depending on the particle size and shape of the phosphor particles.

That is, the light distribution profile of the fluorescence extracted outside is different for each phosphor layer. When the fluorescent component emitted from the first fluorescent layer 91 and the fluorescent component emitted from the second fluorescent layer 92 having different emission profiles are incident on the light distribution adjustment layer 111 and the light distribution adjustment layer 112, respectively, the incident fluorescence In the light distribution adjusting layer, the traveling direction of light changes due to light scattering. At this time, the light path length in the light distribution adjustment layer is longer in the latter case between light incident perpendicularly to the surface of the light distribution adjustment layer and light incident in an oblique direction. Therefore, the latter light with respect to the former is often scattered in the light distribution adjusting layer. In other words, the fluorescence having a light emission profile in which the luminance is higher as the viewing angle is larger, and the luminance in at least 0 ° direction is equal to or higher than the luminance in the oblique direction through the light distribution adjustment layer. The components are extracted to the outside as light emission 94 from the first phosphor layer 91 and light emission 95 from the second phosphor layer 92. As a result, it is possible to obtain a light emitting device that does not change in brightness when viewed from any direction and does not change color when viewed from any direction.

In this structure, since the low refractive index layer 71 is provided between the phosphor layer and the wavelength selective transmission / reflection layer 61, light is emitted from the phosphor layer opposite to the light extraction side (back side). Among the fluorescent components, the fluorescent light incident on the interface is reflected at an angle greater than or equal to the critical angle of the interface between the phosphor layer and the low refractive index layer, and can be effectively extracted to the outside as light emission on the light extraction side. In general, the wavelength-selective transmission / reflection layer 61 has a feature that the reflectance of light incident at a shallow angle with respect to the incident surface is reduced. Therefore, when combined with the low refractive index layer 71, the wavelength selective transmission / reflection layer 61 is incident at a shallow angle. The reflected light can be reliably reflected and recycled. That is, by providing the low refractive index layer 71 between the phosphor layers 91 to 92 and the light distribution adjusting layer 161 and the wavelength selective transmission / reflection layer 61, the fluorescent component emitted from the phosphor layer can be very efficiently externally provided. It can be taken out.

Further, in this structure, since the low refractive index layer 81 is provided between the substrate 13 and the phosphor layers 91 to 92 and the light distribution control layer 161, the light extraction side of the phosphor layers 91 to 92 is provided. Of the fluorescent component that emits light, the fluorescent component that is emitted at a shallow angle from the phosphor layer is incident on the substrate by reflecting the fluorescence incident on the interface at a critical angle greater than the critical angle of the interface between the phosphor layer and the low refractive index layer. Can be suppressed. That is, although it is incident on the substrate, it is reflected at the interface between the substrate and the outside and cannot be taken out to the outside, and a loss component that is guided in the substrate can be suppressed. That is, by providing the low refractive index layer 81 between the substrate 13 and the phosphor layers 91 to 92, the fluorescent component emitted from the phosphor layers 91 to 92 can be extracted outside without loss.

Further, in this structure, since the light distribution adjustment layer is partitioned by the light absorption layer as viewed from the light extraction direction, the light distribution adjustment layer is guided to prevent light from entering the adjacent pixels. You can also. In this configuration, since the light absorption layers 121 formed between the barrier 51 and the substrate 13 are provided between the light distribution adjustment layers adjacent to each other, the phosphor layers 91 to 92 are provided. It is possible to prevent the fluorescence emitted from the light or the light emitted from the light distribution adjustment layer 161 from entering the adjacent phosphor layers 91 to 92 or the light distribution adjustment layer 161 by light absorption. Can be improved.

Further, in this configuration, since the second light absorption layer 141 formed on the excitation light incident surface of the barrier 51 is provided, the excitation light is the phosphor layers 91 to 92 or the light distribution adjustment. It is possible to prevent the light from entering the adjacent phosphor layers 91 to 92 or the light distribution adjusting layer 161 by light absorption without being incident on the layer 161 and being reflected by the bottom surface of the barrier 51, thereby reducing the display contrast. Can be prevented. Further, in the present configuration, the second color formed between the substrate 13, the first color filter 151 formed between the first light distribution control layer 111 and the second light distribution adjustment layer 112. Since the third color filter 153 formed between the color filter 152 and the third light distribution adjustment layer 161 is provided, the color purity of the fluorescence emitted from each phosphor layer can be increased. The color reproduction range can be expanded.

Further, in this configuration, the third phosphor layer 93 and the third light distribution adjustment layer 113 in the thirteenth embodiment of the previous section are configured by only the light distribution adjustment layer 161, so that it is simple. A light emitting device can be formed by the process. Further, in the corresponding pixel, the thickness of the light distribution adjusting layer can be increased by the thickness of the phosphor layers 91 to 92 of other pixels, so that the light distribution profile can be easily adjusted.

(15) Fifteenth Embodiment FIG. 17 is a schematic sectional view showing a light emitting device according to the fifteenth embodiment. In FIG. 17, the same components as those of the light emitting device 30 shown in FIG.
The light-emitting device 170 includes an excitation light source 11 that emits excitation light, a first phosphor layer 91 that is disposed opposite to the excitation light source, emits fluorescence when excited by the excitation light, and a second phosphor layer 92. A substrate 13 on which a third phosphor layer 93 is formed, and a light distribution adjusting layer that is formed so as to spread on the substrate 13 and changes the emission direction of at least the fluorescence emitted from the phosphor layers 91 to 93 171 and the light-reflective barrier 51 formed on the substrate 13 between the phosphor layers adjacent to each other, and the wavelengths formed on the incident surface side of the phosphor layers 91 to 93 on which the excitation light is incident. Between the selective transmission / reflection layer 61, the phosphor layers 91 to 93, and the wavelength selective transmission / reflection layer 61, the low refractive index layer 71 having a refractive index smaller than that of the phosphor layers 91 to 93, and the light distribution control. Layers 111 to 113 and the firefly Between the phosphor layers 91 to 93, the low refractive index layer 81 having a smaller refractive index than the phosphor layers 91 to 93, and the phosphor layers 91 to 93 adjacent to each other, the substrate 13 and the barrier 51. And a second light absorption layer 141 formed on the excitation light incident surface of the barrier 51.

With reference to FIG. 17, light emission in the light emitting device 170 will be described.
In the light emitting device 170, when excitation light is incident on the first phosphor layer 91, the second phosphor layer 92, and the third phosphor layer 93 from the excitation light source 11, isotropic from each phosphor layer, that is, Light is emitted with equal energy in any direction. However, the light distribution profile of fluorescence extracted from the phosphor layer to the outside often differs depending on the type of phosphor. For example, when the refractive index of the phosphor material or resin material constituting the phosphor layer is different for each phosphor layer, the refraction angle at which the fluorescence extracted outside is refracted at the interface between the phosphor layer and the outside is the phosphor layer It depends on. That is, the light distribution profile of the fluorescence extracted to the outside is different for each phosphor layer. For example, when the phosphor layer is made of an inorganic phosphor material, the light emission characteristics vary depending on the particle size and shape of the phosphor particles.

That is, the light distribution profile of the fluorescence extracted outside is different for each phosphor layer. A fluorescent component emitted from the first fluorescent layer 91, a fluorescent component emitted from the second fluorescent layer 92, and a fluorescent component emitted from the third fluorescent layer 93, each having a different emission profile, are arranged via the substrate 13. When the light enters the light adjustment layer 171, the incident fluorescence changes in the light distribution adjustment layer due to light scattering in the light distribution adjustment layer. At this time, the light path length in the light distribution adjustment layer is longer in the latter case between light incident perpendicularly to the surface of the light distribution adjustment layer and light incident in an oblique direction. Therefore, the latter light with respect to the former is often scattered in the light distribution adjusting layer. In other words, the fluorescence having a light emission profile in which the luminance is higher as the viewing angle is larger, and the luminance in at least 0 ° direction is equal to or higher than the luminance in the oblique direction through the light distribution adjustment layer. The components are extracted to the outside as light emission 94 from the first phosphor layer 91, light emission 95 from the second phosphor layer 92, and light emission 96 from the third phosphor layer 93. As a result, it is possible to obtain a light emitting device that does not change in brightness when viewed from any direction and does not change color when viewed from any direction.

In this structure, since the low refractive index layer 81 is provided between the substrate 13 and the phosphor layers 91 to 93, among the fluorescent components that emit light on the light extraction side of the phosphor layers 91 to 93, By reflecting the fluorescence incident on the interface at a critical angle greater than or equal to the critical angle of the interface between the phosphor layer and the low refractive index layer, it is possible to suppress the fluorescence component emitted at a shallow angle from the phosphor layer from entering the substrate. it can. That is, although it is incident on the substrate, it is reflected at the interface between the substrate and the outside and cannot be taken out to the outside, and a loss component that is guided in the substrate can be suppressed. That is, by providing the low refractive index layer 81 between the substrate 13 and the phosphor layers 91 to 93, the fluorescent component emitted from the phosphor layers 91 to 93 can be extracted outside without loss. In addition, in this structure, since the phosphor layer is partitioned by the light absorption layer when viewed from the light extraction direction, light can be prevented from entering the adjacent pixels by being guided through the phosphor layer. .

In this configuration, since the light absorption layers 121 formed between the barrier 51 and the substrate 13 are provided between the light distribution adjustment layers adjacent to each other, the phosphor layers 91 to 93 are provided. It is possible to prevent the fluorescence emitted from the light from entering the adjacent phosphor layer by light absorption, and the display contrast can be improved.

Further, in this configuration, since the second light absorption layer 141 formed on the excitation light incident surface of the barrier 51 is provided, the excitation light does not enter the phosphor layer and hits the bottom surface of the barrier 51 and is reflected. Thus, it is possible to prevent the penetration of the adjacent phosphor layers by light absorption, and it is possible to prevent the display contrast from being lowered. Further, in this configuration, since the light emitted from the light distribution adjustment layer 171 is extracted as it is without passing through other layers, the light emission profile is optimized only by adjusting the light distribution adjustment layer 171. Can do.

(16) Sixteenth Embodiment FIG. 18 is a schematic sectional view showing a light emitting device according to the sixteenth embodiment. In FIG. 18, the same components as those of the light emitting device 30 shown in FIG.
The light emitting device 180 includes an excitation light source 11 that emits excitation light, a first phosphor layer 91 that is arranged to face the excitation light source, emits fluorescence when excited by the excitation light, and a second phosphor layer 92. A substrate 13 on which a third phosphor layer 93 is formed, and a light distribution adjusting layer that is formed so as to spread on the substrate 13 and changes the emission direction of at least the fluorescence emitted from the phosphor layers 91 to 93 171 and the light-reflective barrier 51 formed on the substrate 13 between the phosphor layers adjacent to each other, and the wavelengths formed on the incident surface side of the phosphor layers 91 to 93 on which the excitation light is incident. Between the selective transmission / reflection layer 61, the phosphor layers 91 to 93, and the wavelength selective transmission / reflection layer 61, the low refractive index layer 71 having a refractive index smaller than that of the phosphor layers 91 to 93, and the light distribution control. Layers 111 to 113 and the firefly Between the phosphor layers 91 to 93, the low refractive index layer 81 having a smaller refractive index than the phosphor layers 91 to 93, and the phosphor layers 91 to 93 adjacent to each other, the substrate 13 and the barrier 51. A light absorption layer 121 formed between each of the light absorption layers, a second light absorption layer 141 formed on the excitation light incident surface of the barrier 51, and an outer layer formed so as to spread on the light distribution adjustment layer 171. The light reflection preventing layer 181 is generally configured. It is roughly composed.

The external light antireflection layer 181 is provided on the light distribution adjustment layer 171 and has, for example, a refractive index gradient between the light distribution adjustment layer 171 and the outside. As the refractive index gradient, when the refractive index of the light distribution adjusting layer 171 is n1 and the external refractive index is n2, the light distribution adjusting layer 171 has a refractive index gradient from the light distribution adjusting layer 171 side toward the outside. It is preferable to have a gradient that gradually changes in the range from n1 to n2 in the thickness direction perpendicular to the light extraction surface. Specifically, it is preferable to have a gradient that changes stepwise or continuously.

With such a configuration, the external light antireflection layer 181 can minimize the external light reflection component that is reflected when the external light hits the light distribution adjustment layer.

Such an external light antireflection layer 181 can be formed, for example, by (a1) laminating a plurality of layers (materials) having different refractive indexes stepwise or continuously. In addition, (a2) one or more microstructures having a minute inclination in the thickness direction are formed, and the proportion of the structure is continuously changed in the thickness direction, thereby preventing external light reflection having a refractive index gradient. Layer 151 can be formed.

With regard to (a1), for example, a structure in which a TiO ₂ layer and a SiO ₂ layer are laminated can be mentioned. In addition, a stacked structure including a combination of an MgO layer and an SiO ₂ layer, a ZrO ₂ layer and an SiO ₂ layer, a PMMA layer and a silicon oil layer, and the like can also be given. However, this embodiment is not limited to the combination of these materials.

Regarding the (a2), examples of the material for forming the microstructure include transparent resins such as polyethylene, polypropylene, polycarbonate, and epoxy, and transparent inorganic materials such as SiO ₂ and Si ₃ N ₄ . Furthermore, it is preferable to add a compound having a high refractive index to these materials, for example, a metal oxide such as TiO ₂ , Cu ₂ O, Fe ₂ O ₃ or the like. However, this embodiment is not limited to these materials.

With reference to FIG. 18, the light emission in the light-emitting device 180 is demonstrated.
In the light emitting device 180, when excitation light is incident on the first phosphor layer 91, the second phosphor layer 92, and the third phosphor layer 93 from the excitation light source 11, isotropic from each phosphor layer, that is, Light is emitted with equal energy in any direction. However, the light distribution profile of fluorescence extracted from the phosphor layer to the outside often differs depending on the type of phosphor. For example, when the refractive index of the phosphor material or resin material constituting the phosphor layer is different for each phosphor layer, the refraction angle at which the fluorescence extracted outside is refracted at the interface between the phosphor layer and the outside is the phosphor layer It depends on. That is, the light distribution profile of the fluorescence extracted to the outside is different for each phosphor layer.

Also, for example, when the phosphor layer is made of an inorganic phosphor material, the light emission characteristics vary depending on the particle size and shape of the phosphor particles. That is, the light distribution profile of the fluorescence extracted to the outside is different for each phosphor layer. A fluorescent component emitted from the first fluorescent layer 91, a fluorescent component emitted from the second fluorescent layer 92, and a fluorescent component emitted from the third fluorescent layer 93, each having a different emission profile, are arranged via the substrate 13. When the light enters the light adjustment layer 171, the incident fluorescence changes in the light distribution adjustment layer due to light scattering in the light distribution adjustment layer. At this time, the light path length in the light distribution adjustment layer is longer in the latter case between light incident perpendicularly to the surface of the light distribution adjustment layer and light incident in an oblique direction. Therefore, the latter light with respect to the former is often scattered in the light distribution adjusting layer. In other words, the fluorescence having a light emission profile in which the luminance is higher as the viewing angle is larger, and the luminance in at least 0 ° direction is equal to or higher than the luminance in the oblique direction through the light distribution adjustment layer. The components are extracted to the outside as light emission 94 from the first phosphor layer 91, light emission 95 from the second phosphor layer 92, and light emission 96 from the third phosphor layer 93. As a result, it is possible to obtain a light emitting device that does not change in brightness when viewed from any direction and does not change color when viewed from any direction.

In this structure, since the low refractive index layer 81 is provided between the substrate 13 and the phosphor layers 91 to 93, among the fluorescent components that emit light on the light extraction side of the phosphor layers 91 to 93, By reflecting the fluorescence incident on the interface at a critical angle greater than or equal to the critical angle of the interface between the phosphor layer and the low refractive index layer, it is possible to suppress the fluorescence component emitted at a shallow angle from the phosphor layer from entering the substrate. it can. That is, although it is incident on the substrate, it is reflected at the interface between the substrate and the outside and cannot be taken out to the outside, and a loss component that is guided in the substrate can be suppressed. That is, by providing the low refractive index layer 81 between the substrate 13 and the phosphor layers 91 to 93, the fluorescent component emitted from the phosphor layers 91 to 93 can be extracted outside without loss.

In addition, in this structure, since the phosphor layer is partitioned by the light absorption layer when viewed from the light extraction direction, light can be prevented from entering the adjacent pixels by being guided through the phosphor layer. . In this configuration, since the light absorption layers 121 formed between the barrier 51 and the substrate 13 are provided between the light distribution adjustment layers adjacent to each other, the phosphor layers 91 to 93 are provided. It is possible to prevent the fluorescence emitted from the light from entering the adjacent phosphor layer by light absorption, and the display contrast can be improved.

Further, in this configuration, since the light emitted from the light distribution adjustment layer 171 is extracted as it is without passing through other layers, the light emission profile is optimized only by adjusting the light distribution adjustment layer 171. Can do. Further, in this configuration, since the external light reflection preventing layer 181 formed on the light distribution adjustment layer 171 is provided, the external light reflection component that the external light reflects upon the light distribution adjustment layer 181 is minimized. Can be suppressed. That is, it is possible to minimize the decrease in contrast in a bright place.

"Display device, phosphor substrate"
Next, details of an embodiment of a display device including a phosphor substrate and a light source will be described.
In the display device including the phosphor substrate according to the present embodiment, the phosphor substrate refers to the phosphor layer, the light distribution adjusting layer, the barrier, and the light absorption layer in the first to sixteenth embodiments of the light emitting device described above. It is a substrate on which etc. are formed. In the display device of the present embodiment, the light source is a substrate (light emitting element substrate) on which an excitation light source is formed in the first to sixteenth embodiments of the light emitting device described above.

In the display device of this embodiment, as the light source, a known ultraviolet LED, blue LED, ultraviolet light emitting inorganic EL element, blue light emitting inorganic EL element, ultraviolet light emitting organic EL element, blue light emitting organic EL element, or the like is used. The embodiment is not limited to these light sources, and a light source produced by a known material or a known manufacturing method can be used.
Here, the ultraviolet light preferably emits light having a main light emission peak of 360 to 410 nm, and the blue light preferably has light emission of a main light emission peak of 410 to 470 nm.

(1) First Embodiment FIG. 19 is a schematic cross-sectional view showing an organic EL element substrate constituting a display device according to a first embodiment.
The display device of this embodiment includes a phosphor substrate comprising a substrate on which a phosphor layer, a light distribution adjusting layer, a barrier, a light absorption layer, and the like are formed in the first to sixteenth embodiments of the light emitting device described above. The organic EL element substrate (light source) 210 is bonded to the phosphor substrate via a planarizing film or the like.

The organic EL element substrate 210 includes a substrate 211 and an organic EL element 212 provided on one surface 211a of the substrate 211. The organic EL element 212 is schematically configured from a first electrode 213, an organic EL layer 214, and a second electrode 215 that are sequentially provided on one surface 211 a of the substrate 211. That is, the organic EL element 212 includes a pair of electrodes including the first electrode 213 and the second electrode 215 and an organic EL layer 214 sandwiched between the pair of electrodes on one surface 211a of the substrate 211. I have. The first electrode 213 and the second electrode 215 function as a pair as an anode or a cathode of the organic EL element 212. The optical distance between the first electrode 213 and the second electrode 215 is adjusted to constitute a microresonator structure (microcavity structure).

The organic EL layer 214 is laminated in order from the first electrode 213 side to the second electrode 215 side, the hole injection layer 216, the hole transport layer 217, the light emitting layer 218, the hole prevention layer 219, the electron transport layer. 220 and an electron injection layer 221.
The hole injection layer 216, the hole transport layer 217, the light emitting layer 218, the hole prevention layer 219, the electron transport layer 220, and the electron injection layer 221 may each have a single layer structure or a multilayer structure. In addition, the hole injection layer 216, the hole transport layer 217, the light emitting layer 218, the hole prevention layer 219, the electron transport layer 220, and the electron injection layer 221 may each be an organic thin film or an inorganic thin film.

The hole injection layer 216 efficiently injects holes from the first electrode 213. The hole transport layer 217 efficiently transports holes to the light emitting layer 218. The electron transport layer 220 efficiently transports electrons to the light emitting layer 218. The electron injection layer 221 efficiently injects electrons from the second electrode 215. The hole injection layer 216, the hole transport layer 217, the electron transport layer 220, and the electron injection layer 221 correspond to a carrier injection transport layer.

The organic EL element 212 is not limited to the above configuration, and the organic EL layer 214 may have a single layer structure of a light emitting layer or a multilayer structure of a light emitting layer and a carrier injection / transport layer. . Specific examples of the configuration of the organic EL element 212 include the following.
(1) Configuration in which only the light emitting layer is provided between the first electrode 213 and the second electrode 215 (2) The hole transport layer and the light emitting layer are formed from the first electrode 213 side toward the second electrode 215 side. Structure (3) laminated in this order (3) Structure in which a light emitting layer and an electron transport layer are laminated in this order from the first electrode 213 side to the second electrode 215 side (4) Second electrode 215 from the first electrode 213 side A structure in which a hole transport layer, a light emitting layer, and an electron transport layer are laminated in this order toward the side (5) From the first electrode 213 side to the second electrode 215 side, the hole injection layer, the hole transport layer (6) A structure in which a light emitting layer and an electron transport layer are laminated in this order (6) From the first electrode 213 side to the second electrode 215 side, a hole injection layer, a hole transport layer, a light emitting layer, an electron transport layer, Structure in which injection layers are laminated in this order (7) First electrode 213 side A structure in which a hole injection layer, a hole transport layer, a light emitting layer, a hole prevention layer, and an electron transport layer are laminated in this order toward the second electrode 215 side (8) From the first electrode 213 side to the second electrode 215 A structure in which a hole injection layer, a hole transport layer, a light emitting layer, a hole prevention layer, an electron transport layer, and an electron injection layer are laminated in this order toward the side (9) From the first electrode 213 side to the second electrode 215 A structure in which a hole injection layer, a hole transport layer, an electron blocking layer, a light emitting layer, a hole blocking layer, an electron transport layer and an electron injection layer are laminated in this order toward the side, these light emitting layer, hole injection layer, Each of the hole transport layer, the hole prevention layer, the electron prevention layer, the electron transport layer and the electron injection layer may have a single layer structure or a multilayer structure. In addition, each of the light emitting layer, the hole injection layer, the hole transport layer, the hole prevention layer, the electron prevention layer, the electron transport layer, and the electron injection layer may be either an organic thin film or an inorganic thin film.

An edge cover 222 is formed so as to cover the end face of the first electrode 213. That is, the edge cover 222 is formed on the one surface 211a of the substrate 211 between the first electrode 213 and the second electrode 215 in order to prevent leakage between the first electrode 213 and the second electrode 215. It is provided so as to cover the edge part of the formed first electrode 213.

Hereinafter, although each structural member which comprises the organic EL element substrate 210, and its formation method are demonstrated concretely, this embodiment is not limited to these structural members and a formation method.

As the substrate 211, for example, an inorganic material substrate made of glass, quartz or the like, a plastic substrate made of polyethylene terephthalate, polycarbazole, polyimide, or the like, an insulating substrate such as a ceramic substrate made of alumina, or the like, or aluminum (Al), iron A metal substrate made of (Fe) or the like, or a substrate coated with an insulating material made of silicon oxide (SiO ₂ ), an organic insulating material or the like on the substrate, or a metal substrate made of aluminum or the like is anodized. Although the board | substrate etc. which performed the insulation process by this method are mentioned, this embodiment is not limited to these board | substrates. Among these substrates, it is possible to form a bent portion and a bent portion without stress, and therefore it is preferable to use a plastic substrate or a metal substrate.

Furthermore, a substrate in which a plastic substrate is coated with an inorganic material and a substrate in which a metal substrate is coated with an inorganic insulating material are preferable. By using a substrate coated with such an inorganic material, deterioration of organic EL due to moisture permeation, which is the biggest problem when a plastic substrate is used as a substrate of an organic EL element substrate (organic EL is particularly low in quantity) It is known that deterioration also occurs with respect to moisture.). In addition, leakage (short) due to protrusions on the metal substrate, which is the biggest problem when a metal substrate is used as the substrate of the organic EL element substrate (the film thickness of the organic EL layer is very thin, about 100 to 200 nm. It is known that leakage (short-circuiting) occurs in the current in the pixel portion due to the above.

In the case of forming a TFT, it is preferable to use a substrate that does not melt at a temperature of 500 ° C. or lower and does not generate distortion as the substrate 211. In addition, since a general metal substrate has a coefficient of thermal expansion different from that of glass, it is difficult to form a TFT on a metal substrate with a conventional production apparatus, but the linear expansion coefficient is 1 × 10 ⁻⁵ / ° C. or less. By using a metal substrate that is an iron-nickel alloy of this type and adjusting the linear expansion coefficient to glass, it becomes possible to form TFTs on the metal substrate at low cost using a conventional production apparatus. In the case of a plastic substrate, since the heat-resistant temperature is very low, after forming the TFT on the glass substrate, the TFT on the glass substrate is transferred to the plastic substrate, thereby transferring the TFT onto the plastic substrate. be able to.

Further, when light emission from the organic EL layer 214 is taken out from the side opposite to the substrate 211, there is no restriction as a substrate, but when light emission from the organic EL layer 214 is taken out from the substrate 211 side, the organic EL layer In order to extract light emitted from 214 to the outside, it is necessary to use a transparent or translucent substrate.

The TFT formed on the substrate 211 is formed in advance on one surface 211a of the substrate 211 before the organic EL element 212 is formed, and functions as a pixel switching element and an organic EL element driving element. As the TFT in this embodiment, a known TFT can be cited. In place of the TFT, a metal-insulator-metal (MIM) diode can also be used.

TFTs that can be used in active drive organic EL display devices and organic EL display devices can be formed using known materials, structures, and formation methods.
Examples of the material of the active layer constituting the TFT include inorganic semiconductor materials such as amorphous silicon (amorphous silicon), polycrystalline silicon (polysilicon), microcrystalline silicon, cadmium selenide, zinc oxide, indium oxide-oxide Examples thereof include oxide semiconductor materials such as gallium-zinc oxide, and organic semiconductor materials such as polythiophene derivatives, thiophene oligomers, poly (p-ferylene vinylene) derivatives, naphthacene, and pentacene. Examples of the TFT structure include a staggered type, an inverted staggered type, a top gate type, and a coplanar type.

As an active layer forming method for forming a TFT, (1) a method of ion doping impurities into amorphous silicon formed by plasma induced chemical vapor deposition (PECVD), and (2) a silane (SiH ₄ ) gas is used. Forming amorphous silicon by low pressure chemical vapor deposition (LPCVD), crystallizing amorphous silicon by solid phase growth to obtain polysilicon, and then ion doping by ion implantation, (3) Si ₂ H Amorphous silicon is formed by LPCVD using ₆ gases or PECVD using SiH ₄ gas, annealed by a laser such as an excimer laser, etc., and amorphous silicon is crystallized to obtain polysilicon, followed by ion doping (Low temperature process), (4) LPCVD method or The polysilicon layer is formed by ECVD method, a gate insulating film formed by thermal oxidation at 1000 ° C. or higher, thereon to form a gate electrode of the n ⁺ polysilicon, then, a method of performing ion doping (high temperature Process), (5) a method of forming an organic semiconductor material by an inkjet method, and (6) a method of obtaining a single crystal film of the organic semiconductor material.

The gate insulating film constituting the TFT in this embodiment can be formed using a known material. As the gate insulating film, for example, PECVD method, and a SiO ₂ or polysilicon film formed by the LPCVD method or the like insulating film made of SiO ₂ or the like obtained by thermal oxidation.

In addition, the signal electrode line, the scanning electrode line, the common electrode line, the first drive electrode, and the second drive electrode of the TFT in this embodiment can be formed using a known material. Examples of the material of the signal electrode line, the scan electrode line, the common electrode line, the first drive electrode, and the second drive electrode include tantalum (Ta), aluminum (Al), copper (Cu), and the like. The TFT of the organic EL element substrate 210 can be configured as described above, but the present embodiment is not limited to these materials, structures, and formation methods.

The interlayer insulating film that can be used in the active drive organic EL display device and the organic EL display device can be formed using a known material. As a material of the interlayer insulating film, for example, inorganic materials such as silicon oxide (SiO ₂ ), silicon nitride (SiN or Si ₂ N ₄ ), tantalum oxide (TaO or Ta ₂ O ₅ ), acrylic resin, resist material Organic materials, etc. are mentioned.
Examples of the method for forming the interlayer insulating film include a dry process such as a chemical vapor deposition (CVD) method and a vacuum deposition method, and a wet process such as a spin coating method. If necessary, the interlayer insulating film can be patterned by a photolithography method or the like.

When light emitted from the organic EL element 212 is extracted from the side opposite to the substrate 211 (second electrode 215 side), external light is incident on the TFT formed on the one surface 211a of the substrate 211, and the characteristics of the TFT. In order to prevent the change from occurring, it is preferable to form a light-shielding insulating film having light-shielding properties. Further, the interlayer insulating film and the light-shielding insulating film can be used in combination. Examples of the material of the light-shielding insulating film include, for example, pigments or dyes such as phthalocyanine and quinaclonone dispersed in a polymer resin such as polyimide, color resists, black matrix materials, and inorganic insulating materials such as Ni _x Zn _y Fe ₂ O ₄ Although materials etc. are mentioned, this embodiment is not limited to these materials and a formation method.

In the active drive type organic EL display device, when a TFT or the like is formed on one surface 211a of the substrate 211, an unevenness is formed on the surface, and this unevenness causes a defect in the organic EL element 212 (for example, a pixel electrode defect). There is a risk that a defect of the organic EL layer, a disconnection of the second electrode, a short circuit between the first electrode and the second electrode, a decrease in breakdown voltage, or the like) may occur. In order to prevent these defects, a planarizing film may be provided on the interlayer insulating film.

Such a planarization film can be formed using a known material. Examples of the material for the planarizing film include inorganic materials such as silicon oxide, silicon nitride, and tantalum oxide, and organic materials such as polyimide, acrylic resin, and resist material. Examples of the method for forming the planarization film include a dry process such as a CVD method and a vacuum deposition method, and a wet process such as a spin coating method. However, the present embodiment is limited to these materials and the formation method. is not. Further, the planarization film may have either a single layer structure or a multilayer structure.

The first electrode 213 and the second electrode 215 function as a pair as an anode or a cathode of the organic EL element 212. That is, when the first electrode 213 is an anode, the second electrode 215 is a cathode, and when the first electrode 213 is a cathode, the second electrode 215 is an anode.

As an electrode material for forming the first electrode 213 and the second electrode 215, a known electrode material can be used. As an electrode material for forming the anode, gold (Au), platinum (Pt), nickel (Ni) or the like having a work function of 4.5 eV or more from the viewpoint of more efficiently injecting holes into the organic EL layer 214. Metal, oxide (ITO) composed of indium (In) and tin (Sn), oxide (SnO ₂ ) of tin (Sn), oxide (IZO) composed of indium (In) and zinc (Zn) Transparent electrode materials and the like.

Moreover, as an electrode material for forming the cathode, lithium (Li), calcium (Ca), cerium (Ce) having a work function of 4.5 eV or less from the viewpoint of more efficiently injecting electrons into the organic EL layer 214. And metals such as barium (Ba) and aluminum (Al), or alloys such as Mg: Ag alloys and Li: Al alloys containing these metals.

The first electrode 213 and the second electrode 215 can be formed by a known method such as an EB vapor deposition method, a sputtering method, an ion plating method, or a resistance heating vapor deposition method using the above-described materials. Is not limited to these forming methods. Moreover, the electrode formed by the photolithographic method and the laser peeling method can also be patterned as needed, and the electrode patterned directly by combining with a shadow mask can also be formed.
The film thicknesses of the first electrode 213 and the second electrode 215 are preferably 50 nm or more. When the film thickness is less than 50 nm, the wiring resistance increases and the drive voltage may increase.

When the microcavity effect is used for the purpose of improving the color purity of the display device, improving the light emission efficiency, improving the front luminance, etc., or when emitting light from the organic EL layer 214 from the first electrode 213 or the second electrode 215 side It is preferable to use a translucent electrode as the first electrode 213 or the second electrode 215. As a material for the semitransparent electrode, a metal semitransparent electrode alone or a combination of a metal translucent electrode and a transparent electrode material can be used. In particular, as a material for the semitransparent electrode, silver is preferable from the viewpoint of reflectance and transmittance.

The film thickness of the translucent electrode is preferably 5 to 30 nm. When the film thickness of the translucent electrode is less than 5 nm, the light cannot be sufficiently reflected, and the interference effect cannot be obtained sufficiently. In addition, when the film thickness of the translucent electrode exceeds 30 nm, the light transmittance is rapidly decreased, so that the luminance and light emission efficiency of the display device may be decreased.
In addition, as the first electrode 213 or the second electrode 215, it is preferable to use an electrode with high reflectivity that reflects light. Examples of the electrode having high reflectivity include a reflective metal electrode (reflective electrode) made of, for example, aluminum, silver, gold, aluminum-lithium alloy, aluminum-neodymium alloy, aluminum-silicon alloy, and the like. The electrode etc. which combined are mentioned.

The charge injection / transport layer is a charge injection layer (hole injection layer 216, electron injection layer 221) for the purpose of more efficiently injecting charges (holes, electrons) from the electrode and transporting (injection) to the light emitting layer. And a charge transport layer (hole transport layer 217, electron transport layer 220), and may be composed only of the charge injection transport material exemplified below, and optionally includes additives (donor, acceptor, etc.). Alternatively, a structure in which these materials are dispersed in a polymer material (binding resin) or an inorganic material may be used.

As the charge injecting and transporting material, known charge injecting and transporting materials for organic EL elements and organic photoconductors can be used. Such charge injecting and transporting materials are classified into hole injecting and transporting materials and electron injecting and transporting materials. Specific examples of these compounds are given below, but this embodiment is not limited to these materials. .

As materials for the hole injection layer 216 and the hole transport layer 217, known materials are used. For example, oxides such as vanadium oxide (V ₂ O ₅ ) and molybdenum oxide (MoO ₂ ), and inorganic p-type semiconductor materials are used. A porphyrin compound, N, N′-bis (3-methylphenyl) -N, N′-bis (phenyl) -benzidine (TPD), N, N′-di (naphthalen-1-yl) -N, N ′ -Diphenyl-benzidine (α-NPD), 4,4 ', 4 "-tris (carbazol-9-yl) triphenylamine (TCTA), N, N-dicarbazolyl-3,5-benzene (m-CP), 4,4 ′-(cyclohexane-1,1-diyl) bis (N, N-di-p-tolylaniline) (TAPC), 2,2′-bis (N, N-diphenylamine) -9,9′- Spirofluorene (DPA S), N1, N1 ′-(biphenyl-4,4′-diyl) bis (N1-phenyl-N4, N4-di-m-tolylbenzene-1,4-diamine) (DNTPD), N3, N3, N3 "', N3"'-tetra-p-tolyl- [1,1 ': 2', 1 ": 2", 1 "'-quarterphenyl] -3,3"'-diamine (BTPD), 4,4 Aromatics such as'-(diphenylsilanediyl) bis (N, N-di-p-tolylaniline) (DTASi), 2,2-bis (4-carbazol-9-ylphenyl) adamantine (Ad-Cz) Tertiary amine compounds; low molecular nitrogen compounds such as hydrazone compounds, quinacridone compounds, styrylamine compounds; polyaniline (PANI), polyaniline-camphor sulfonic acid (PANI-CSA), 3,4-polyethylenedioxythio Fen / polystyrene sulfonate (PEDOT / PSS), poly (triphenylamine) derivative (Poly-TPD), polyvinylcarbazole (PVCz), poly (p-phenylene vinylene) (PPV), poly (p-naphthalene vinylene) ( PNV) and the like; and aromatic hydrocarbon compounds such as 2-methyl-9,10-bis (naphthalen-2-yl) anthracene (MADN).

As the material of the hole injection layer 216, the energy level of the highest occupied molecular orbital (HOMO) is higher than that of the material of the hole transport layer 217 from the viewpoint of more efficiently injecting and transporting holes from the anode. It is preferable to use a low material. As a material for the hole transport layer 217, a material having higher hole mobility than the material for the hole injection layer 216 is preferably used.

The hole injection layer 216 and the hole transport layer 217 may optionally contain an additive (donor, acceptor, etc.). In order to further improve the hole injection property and the transport property, the hole injection layer 216 and the hole transport layer 217 preferably include an acceptor. As the acceptor, a known acceptor material for organic EL elements can be used. Although these specific compounds are illustrated below, this embodiment is not limited to these materials.

The acceptor may be either an inorganic material or an organic material.
Examples of the inorganic material include gold (Au), platinum (Pt), tungsten (W), iridium (Ir), phosphorus oxychloride (POCl ₃ ), hexafluoroarsenate ion (AsF ₆ ⁻ ), chlorine (Cl), Examples include bromine (Br), iodine (I), vanadium oxide (V ₂ O ₅ ), molybdenum oxide (MoO ₂ ), and the like.

Examples of organic materials include 7,7,8,8, -tetracyanoquinodimethane (TCNQ), tetrafluorotetracyanoquinodimethane (TCNQF ₄ ), tetracyanoethylene (TCNE), hexacyanobutadiene (HCNB), and dicyclohexane. Compounds having a cyano group such as dicyanobenzoquinone (DDQ); compounds having a nitro group such as trinitrofluorenone (TNF) and dinitrofluorenone (DNF); fluoranil; chloranil; bromanyl and the like.
Among these, compounds having a cyano group such as TCNQ, TCNQF ₄ , TCNE, HCNB, and DDQ are preferable because the effect of increasing the hole concentration is higher.

As materials for the hole blocking layer 219, the electron transporting layer 220, and the electron injecting layer 221, known materials are used. In the case of a low molecular material, an inorganic material that is an n-type semiconductor; 1,3-bis [2- (2,2′-bipyridin-6-yl) -1,3,4-oxadiazo-5-yl] benzene (Bpy-OXD), 1,3-bis (5- (4- (tert-butyl) phenyl) Oxadiazole derivatives such as -1,3,4-oxadiazol-2-yl) benzene (OXD7); 3- (4-biphenyl) -4-phenyl-5-tert-butylphenyl-1,2,4 -Triazole derivatives such as triazole (TAZ); thiopyrazine dioxide derivative; benzoquinone derivative; naphthoquinone derivative; anthraquinone derivative; diphenoquinone derivative; fluorenone derivative; Difuran derivatives; quinoline derivatives such as 8-hydroxyquinolinolato-lithium (Liq); 2,7-bis [2- (2,2′-bipyridin-6-yl) -1,3,4-oxadiazo-5- Yl] -9,9-dimethylfluorene (Bpy-FOXD) and the like; 1,3,5-tri [(3-pyridyl) -phen-3-yl] benzene (TmPyPB), 1,3,5- Benzene derivatives such as tri [(3-pyridyl) -phen-3-yl] benzene (TpPyPB); 2,2 ′, 2 ″-(1,3,5-benzentriyl) -tris (1-phenyl-1 Benzimidazole derivatives such as —H-benzimidazole) (TPBI); pyridine derivatives such as 3,5-di (pyren-1-yl) pyridine (PY1); 3,3 ′, 5,5′-tetra [(m -Pirigi Biphenyl derivatives such as (l) -phen-3-yl] biphenyl (BP4mPy); 4,7-diphenyl-1,10-phenanthroline (BPhen), 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline Phenanthroline derivatives such as (BCP); triphenylborane derivatives such as tris (2,4,6-trimethyl-3- (pyridin-3-yl) phenyl) borane (3TPYMB); diphenylbis (4- (pyridine-3- Yl) phenyl) silane (DPPS) and other tetraphenylsilane derivatives; poly (oxadiazole) (Poly-OXZ), polystyrene derivatives (PSS), etc. In particular, the material of the electron injection layer 221 includes fluorination. lithium (LiF), a fluoride such as barium fluoride (BaF _2); lithium oxide Li ₂ O) oxides such like.

As a material of the electron injection layer 221, a material having a higher energy level of the lowest unoccupied molecular orbital (LUMO) than that of the material of the electron transport layer 220 is used from the viewpoint of more efficiently injecting and transporting electrons from the cathode. Is preferred. As a material for the electron transport layer 220, a material having higher electron mobility than the material for the electron injection layer 221 is preferably used.

The electron transport layer 220 and the electron injection layer 221 may optionally contain an additive (donor, acceptor, etc.). In order to further improve the electron transport property and the injection property, the electron transport layer 220 and the electron injection layer 221 preferably include a donor. As a donor, the well-known donor material for organic EL elements can be used. Although these specific compounds are illustrated below, this embodiment is not limited to these materials.

The donor may be either an inorganic material or an organic material.
Examples of the inorganic material include alkali metals such as lithium, sodium and potassium; alkaline earth metals such as magnesium and calcium; rare earth elements; aluminum (Al); silver (Ag); copper (Cu); It is done.

Examples of the organic material include a compound having an aromatic tertiary amine skeleton, a condensed polycyclic compound which may have a substituent such as phenanthrene, pyrene, perylene, anthracene, tetracene and pentacene, tetrathiafulvalene (TTF), Examples include dibenzofuran, phenothiazine, and carbazole.

Compounds having an aromatic tertiary amine skeleton include anilines; phenylenediamines; N, N, N ′, N′-tetraphenylbenzidine, N, N′-bis- (3-methylphenyl) -N, N Benzidines such as' -bis- (phenyl) -benzidine, N, N'-di (naphthalen-1-yl) -N, N'-diphenyl-benzidine; triphenylamine, 4,4'4 "-tris ( N, N-diphenyl-amino) -triphenylamine, 4,4'4 "-tris (N-3-methylphenyl-N-phenyl-amino) -triphenylamine, 4,4'4" -tris (N Triphenylamines such as-(1-naphthyl) -N-phenyl-amino) -triphenylamine; N, N'-di- (4-methyl-phenyl) -N, N'-diphenyl-1,4- Phenyle Triphenyldiamine such as diamines, and the like.

The above-mentioned condensed polycyclic compound “has a substituent” means that one or more hydrogen atoms in the condensed polycyclic compound are substituted with a group other than a hydrogen atom (substituent). The number of is not particularly limited, and all hydrogen atoms may be substituted with a substituent. The position of the substituent is not particularly limited. Examples of the substituent include an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, an alkenyl group having 2 to 10 carbon atoms, an alkenyloxy group having 2 to 10 carbon atoms, and an aryl group having 6 to 15 carbon atoms. An aryloxy group having 6 to 15 carbon atoms, a hydroxyl group, a halogen atom, and the like.

The alkyl group may be linear, branched or cyclic.
Examples of the linear or branched alkyl group include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, sec-butyl group, tert-butyl group, and n-pentyl group. , Isopentyl group, neopentyl group, tert-pentyl group, 1-methylbutyl group, n-hexyl group, 2-methylpentyl group, 3-methylpentyl group, 2,2-dimethylbutyl group, 2,3-dimethylbutyl group, n-heptyl group, 2-methylhexyl group, 3-methylhexyl group, 2,2-dimethylpentyl group, 2,3-dimethylpentyl group, 2,4-dimethylpentyl group, 3,3-dimethylpentyl group, 3 -Ethylpentyl group, 2,2,3-trimethylbutyl group, n-octyl group, isooctyl group, nonyl group, decyl group and the like.

The cyclic alkyl group may be monocyclic or polycyclic, cyclopropyl group, cyclobutyl group, cyclopentyl group, cyclohexyl group, cycloheptyl group, cyclooctyl group, cyclononyl group, cyclodecyl group, norbornyl group, isobornyl Group, 1-adamantyl group, 2-adamantyl group, tricyclodecyl group and the like.

Examples of the alkoxy group include a monovalent group in which an alkyl group is bonded to an oxygen atom. Examples of the alkenyl group include an alkyl group having 2 to 10 carbon atoms in which one single bond (C—C) between carbon atoms is substituted with a double bond (C═C). Examples of the alkenyloxy group include a monovalent group in which the alkenyl group is bonded to an oxygen atom.

The aryl group may be monocyclic or polycyclic, and the number of ring members is not particularly limited, and preferred examples include a phenyl group, a 1-naphthyl group, a 2-naphthyl group, and the like. Examples of the aryloxy group include a monovalent group in which an aryl group is bonded to an oxygen atom. Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom.

Among these, as the donor, a compound having an aromatic tertiary amine skeleton, a condensed polycyclic compound which may have a substituent, and an alkali metal are preferable because the effect of increasing the electron concentration is higher.

The light-emitting layer 218 may be composed only of the organic light-emitting material exemplified below, or may be composed of a combination of a light-emitting dopant and a host material, and optionally includes a hole transport material, an electron transport material, and an addition An agent (donor, acceptor, etc.) may be included. Moreover, the structure by which these each material was disperse | distributed in the polymeric material (binding resin) or the inorganic material may be sufficient. From the viewpoint of light emission efficiency and durability, the material of the light emitting layer 218 is preferably a material in which a light emitting dopant is dispersed in a host material.

As the organic light emitting material, a known light emitting material for an organic EL element can be used. Such light-emitting materials are classified into low-molecular light-emitting materials, polymer light-emitting materials, and the like. Specific examples of these compounds are given below, but the present embodiment is not limited to these materials.

As a low molecular light emitting material (including a host material) used for the light emitting layer 218, an aromatic dimethylidene compound such as 4,4′-bis (2,2′-diphenylvinyl) -biphenyl (DPVBi); Oxadiazole compounds such as 2- [2- [4- (5-methyl-2-benzoxazolyl) phenyl] vinyl] benzoxazole; 3- (4-biphenyl) -4-phenyl-5-t-butyl Triazole derivatives such as phenyl-1,2,4-triazole (TAZ); styrylbenzene compounds such as 1,4-bis (2-methylstyryl) benzene; thiopyrazine dioxide derivatives, benzoquinone derivatives, naphthoquinone derivatives, anthraquinone derivatives, Fluorescent organic materials such as diphenoquinone derivatives and fluorenone derivatives; azomethine zinc complexes, (8- Rokishikinorinato) aluminum complex (Alq ₃₎ fluorescence emitting organic metal complex such as, BeBq (bis (benzoquinolinolato) beryllium complex); 4,4'-bis - (2,2-di -p- tolyl - vinyl) - Biphenyl (DTVBi); Tris (1,3-diphenyl-1,3-propanediono) (monophenanthroline) Eu (III) (Eu (DBM) ₃ (Phen)); Diphenylethylene derivative; Tris [4- (9- Triphenylamine derivatives such as phenylfluoren-9-yl) phenyl] amine (TFTPA); diaminocarbazole derivatives; bisstyryl derivatives; aromatic diamine derivatives; quinacridone compounds; perylene compounds; coumarin compounds; ); Oligothiophene derivatives (BMA- T); 4,4′-di (triphenylsilyl) -biphenyl (BSB), diphenyl-di (o-tolyl) silane (UGH1), 1,4-bistriphenylsilylbenzene (UGH2), 1,3-bis Silane derivatives such as (triphenylsilyl) benzene (UGH3), triphenyl- (4- (9-phenyl-9H-fluoren-9-yl) phenyl) silane (TPSi-F); 9,9-di (4- Dicarbazole-benzyl) fluorene (CPF), 3,6-bis (triphenylsilyl) carbazole (mCP), 4,4′-bis (carbazol-9-yl) biphenyl (CBP), 4,4′-bis ( Carbazol-9-yl) -2,2′-dimethylbiphenyl (CDBP), N, N-dicarbazolyl-3,5-benzene (m-CP), 3- (diphenyl) Phosphoryl) -9-phenyl-9H-carbazole (PPO1), 3,6-di (9-carbazolyl) -9- (2-ethylhexyl) carbazole (TCz1), 9,9 '-(5- (triphenylsilyl) -1,3-phenylene) bis (9H-carbazole) (SimCP), bis (3,5-di (9H-carbazol-9-yl) phenyl) diphenylsilane (SimCP2), 3- (diphenylphosphoryl) -9- (4-Diphenylphosphoryl) phenyl) -9H-carbazole (PPO21), 2,2-bis (4-carbazolylphenyl) -1,1-biphenyl (4CzPBP), 3,6-bis (diphenylphosphoryl) -9 -Phenyl-9H-carbazole (PPO2), 9- (4-tert-butylphenyl) -3,6-bis (trif Nylsilyl) -9H-carbazole (CzSi), 3,6-bis [(3,5-diphenyl) phenyl] -9-phenyl-carbazole (CzTP), 9- (4-tert-butylphenyl) -3,6- Ditrityl-9H-carbazole (CzC), 9- (4-tert-butylphenyl) -3,6-bis (9- (4-methoxyphenyl) -9H-fluoren-9-yl) -9H-carbazole (DFC) 2,2′-bis (4-carbazol-9-yl) phenyl) -biphenyl (BCBP), 9,9 ′-((2,6-diphenylbenzo [1,2-b: 4,5-b ′ Carbazole derivatives such as difuran-3,7-diyl) bis (4,1-phenylene)) bis (9H-carbazole) (CZBDF); 4- (diphenylphosphoyl) -N, N Aniline derivatives such as diphenylaniline (HM-A1); 1,3-bis (9-phenyl-9H-fluoren-9-yl) benzene (mDPFB), 1,4-bis (9-phenyl-9H-fluorene-9 -Yl) benzene (pDPFB), 2,7-bis (carbazol-9-yl) -9,9-dimethylfluorene (DMFL-CBP), 2- [9,9-di (4-methylphenyl) -fluorene- 2-yl] -9,9-di (4-methylphenyl) fluorene (BDAF), 2- (9,9-spirobifluoren-2-yl) -9,9-spirobifluorene (BSBF), 9-bis [4- (pyrenyl) phenyl] -9H-fluorene (BPPF), 2,2′-dipyrenyl-9,9-spirobifluorene (Spiro-Pye), 2,7-dipyreni -9,9-spirobifluorene (2,2'-Spiro-Pye), 2,7-bis [9,9-di (4-methylphenyl) -fluoren-2-yl] -9,9-di ( 4-methylphenyl) fluorene (TDAF), 2,7-bis (9,9-spirobifluoren-2-yl) -9,9-spirobifluorene (TSBF), 9,9-spirobifluorene-2- Fluorene derivatives such as yl-diphenyl-phosphine oxide (SPPO1); pyrene derivatives such as 1,3-di (pyren-1-yl) benzene (m-Bpye); propane-2,2′-diylbis (4,1 Benzoate derivatives such as -phenylene) dibenzoate (MMA1); 4,4′-bis (diphenylphosphine oxide) biphenyl (PO1), 2,8-bis (diphenylphosphine) Olyl) dibenzo [b, d] thiophene (PPT) and other phosphine oxide derivatives; terphenyl derivatives such as 4,4 ″ -di (triphenylsilyl) -p-terphenyl (BST); 2,4-bis ( And triazine derivatives such as phenoxy) -6- (3-methyldiphenylamino) -1,3,5-triazine (BPMT).

Polymer light-emitting materials used for the light-emitting layer 218 include poly (2-decyloxy-1,4-phenylene) (DO-PPP), poly [2,5-bis- [2- (N, N, N-triethyl). ammonium) ethoxy] -1,4-phenyl - Alto 1,4 phenyl alkylene] dibromide ^{(PPP-NEt 3+),} poly [2- (2'-ethylhexyl oxy) -5-methoxy-1,4-phenylene Vinylene] (MEH-PPV), poly [5-methoxy- (2-propanoxysulfonide) -1,4-phenylenevinylene] (MPS-PPV), poly [2,5-bis- (hexyloxy)- Polyphenylene vinylene derivatives such as 1,4-phenylene- (1-cyanovinylene)] (CN-PPV); poly (9,9-dioctylfluorene) (PDAF) Pyro derivatives; poly (N- vinylcarbazole) (PVK), etc. carbazole derivatives, and the like.

The organic light emitting material is preferably a low molecular light emitting material, and a phosphorescent material having high light emission efficiency is preferably used from the viewpoint of reducing power consumption.

As a luminescent dopant used for the light emitting layer 218, a well-known dopant for organic EL elements can be used. As the dopant, in the case of an ultraviolet light emitting material, p-quaterphenyl, 3,5,3,5-tetra-tert-butylsecphenyl, 3,5,3,5-tetra-tert-butyl-p- Examples thereof include fluorescent light emitting materials such as quinckphenyl. In the case of a blue light emitting material, a fluorescent light emitting material such as a styryl derivative; bis [(4,6-difluorophenyl) -pyridinato-N, C2 ′] picolinate iridium (III) (FIrpic), bis (4 ′, 6 And phosphorescent organic metal complexes such as' -difluorophenylpolydinato) tetrakis (1-pyrazoyl) borate iridium (III) (FIr6). Examples of the green light emitting material include phosphorescent organic metal complexes such as tris (2-phenylpyridinate) iridium (Ir (ppy) ₃ ).

In addition, although the material of each layer which comprises the organic EL layer 214 was demonstrated, for example, a host material can also be used as a hole transport material or an electron transport material, and a hole transport material and an electron transport material can also be used as a host material.

As a method for forming each of the hole injection layer 216, the hole transport layer 217, the light emitting layer 218, the hole prevention layer 219, the electron transport layer 220, and the electron injection layer 221, a known wet process, dry process, and laser transfer method are used. Etc. are used.
As the wet process, a coating method such as a spin coating method, a dipping method, a doctor blade method, a discharge coating method, a spray coating method, or the like using a liquid in which a material constituting each layer is dissolved or dispersed in a solvent; an inkjet method; Examples thereof include a printing method such as a relief printing method, an intaglio printing method, a screen printing method, and a micro gravure coating method. The liquid used in the above coating method and printing method may contain additives for adjusting the physical properties of the liquid, such as a leveling agent and a viscosity modifier.

As the dry process, a resistance heating vapor deposition method, an electron beam (EB) vapor deposition method, a molecular beam epitaxy (MBE) method, a sputtering method, an organic vapor phase vapor deposition (OVPD) method, or the like, using the material constituting each of the above layers is used. It is done.
The thickness of each of the hole injection layer 216, the hole transport layer 217, the light emitting layer 218, the hole prevention layer 219, the electron transport layer 220, and the electron injection layer 221 is usually about 1 to 1000 nm, but 10 to 200 nm. Is preferred. If the film thickness is less than 10 nm, the properties (charge injection characteristics, transport characteristics, confinement characteristics) that are originally required cannot be obtained. In addition, pixel defects due to foreign matters such as dust may occur. On the other hand, when the film thickness exceeds 200 nm, the driving voltage increases due to the resistance component of the organic EL layer 214, resulting in an increase in power consumption.

The edge cover 222 can be formed by using an insulating material by a known method such as an EB vapor deposition method, a sputtering method, an ion plating method, a resistance heating vapor deposition method, or the like by a known dry method or a wet photolithography method. Patterning can be performed, but the present embodiment is not limited to these forming methods. In addition, a known material is used as the insulating material constituting the edge cover 222, but the insulating material is not particularly limited in the present embodiment. Since the edge cover 222 needs to transmit light, examples of the insulating material constituting the edge cover 222 include SiO, SiON, SiN, SiOC, SiC, HfSiON, ZrO, HfO, and LaO.

The film thickness of the edge cover 222 is preferably 100 to 2000 nm. If the film thickness is less than 100 nm, the insulating property is not sufficient, and leakage occurs between the first electrode 213 and the second electrode 215, resulting in an increase in power consumption and non-light emission. On the other hand, if the film thickness exceeds 2000 nm, the film forming process takes time, which causes a decrease in production efficiency and causes the second electrode 215 to be disconnected by the edge cover 222.

Here, the organic EL element 212 has a microcavity structure (optical microresonator structure) based on an interference effect between the first electrode 213 and the second electrode 215, or a microcavity structure (optical microresonator structure) based on a dielectric multilayer film. ). When the first resonator 213 and the second electrode 215 form a microresonator structure, the organic EL layer 214 emits light in the front direction (light extraction direction) due to the interference effect between the first electrode 213 and the second electrode 215. It can be condensed. At that time, since the light emission of the organic EL layer 214 can have directivity, the light emission loss escaping to the surroundings can be reduced, and the light emission efficiency can be increased. Thereby, it is possible to more efficiently propagate the light emission energy generated in the organic EL layer 214 to the phosphor layer, and the front luminance of the display device can be increased.

In addition, due to the interference effect between the first electrode 213 and the second electrode 215, the emission spectrum of the organic EL layer 214 can be adjusted, and the desired emission peak wavelength and half width can be adjusted. Thereby, it is possible to control the red phosphor and the green phosphor to a spectrum that can be excited more effectively, and the color purity of the blue pixel can be improved.

Further, the display device of this embodiment is electrically connected to an external drive circuit (scanning line electrode circuit, data signal electrode circuit, power supply circuit).
Here, as the substrate 211 constituting the organic EL element substrate 210, a substrate coated with an insulating material on a glass substrate, more preferably a metal substrate or a substrate coated with an insulating material on a plastic substrate, more preferably a metal substrate. A substrate obtained by coating an insulating material on an upper or plastic substrate is used.

Further, the display device of this embodiment may be driven by directly connecting the organic EL element substrate 210 to an external circuit, or a switching circuit such as a TFT is disposed in a pixel, and wiring connected to the TFT or the like An external drive circuit (scanning line electrode circuit (source driver), data signal electrode circuit (gate driver), power supply circuit) for driving the organic EL element substrate 210 may be electrically connected.

In the present embodiment, it is preferable to provide a color filter between the phosphor substrate and the organic EL element substrate 210. A conventional color filter can be used as the color filter. Thus, by providing the color filter, the color purity of the red pixel, the green pixel, and the blue pixel can be increased, and the color reproduction range of the display device can be expanded. In addition, the blue color filter formed on the blue phosphor layer, the green color filter formed on the green phosphor layer, and the red color filter formed on the red phosphor layer include excitation light contained in external light. Since the component is absorbed, light emission of the phosphor layer due to external light can be reduced or prevented, and a reduction in contrast can be reduced or prevented. Furthermore, the blue color filter formed on the blue phosphor layer, the green color filter formed on the green phosphor layer, and the red color filter formed on the red phosphor layer are not absorbed by the phosphor layer, Since the excitation light to be transmitted can be prevented from leaking to the outside, it is possible to prevent the color purity of the display from being deteriorated due to a mixture of light emitted from the phosphor layer and excitation light.

According to the display device of the present embodiment, the brightness does not change when viewed from any direction, the color does not change when viewed from any direction, and the power consumption can be reduced. A display device can be realized.

(2) Second Embodiment FIG. 20 is a schematic sectional view showing an LED element substrate constituting a display device according to a second embodiment. The display device of this embodiment includes a phosphor substrate comprising a substrate on which a phosphor layer, a light distribution adjusting layer, a barrier, a light absorption layer, and the like are formed in the first to sixteenth embodiments of the light emitting device described above. The LED substrate (light source) 230 is bonded to the phosphor substrate via a flattening film or the like.

The LED substrate 230 includes a substrate 231, a first buffer layer 232, an n-type contact layer 233, a second n-type cladding layer 234, and a first n-type cladding that are sequentially stacked on one surface 211 a of the substrate 211. A layer 235, an active layer 236, a first p-type cladding layer 237, a second p-type cladding layer 238, a second buffer layer 239, a cathode 240 formed on the n-type contact layer 233, and a second An anode 241 formed on the buffer layer 239 is schematically configured. In addition, as LED, other well-known LED, for example, ultraviolet light emission inorganic LED, blue light emission inorganic LED, etc. can be used, However, A specific structure is not limited to said thing.

Hereinafter, each component of the LED substrate 230 will be described in detail.
The active layer 236 is a layer that emits light by recombination of electrons and holes, and a known active layer material for LED can be used as the active layer material. As such an active layer material, for example, as an ultraviolet active layer material, AlGaN, InAlN, In _a Al _b Ga _1-ab N (0 ≦ a, 0 ≦ b, a + b ≦ 1), blue active layer material _Examples thereof include In _z Ga _1-z N (0 <z <1), but the present embodiment is not limited to these. The active layer 236 has a single quantum well structure or a multiple quantum well structure. The active layer of the quantum well structure may be either n-type or p-type. However, when it is a non-doped (no impurity added) active layer, the half-value width of the emission wavelength is narrowed due to interband emission, and light emission with good color purity is achieved. Since it is obtained, it is preferable.

Further, the active layer 236 may be doped with at least one of a donor impurity and an acceptor impurity. If the crystallinity of the active layer doped with the impurity is the same as that of the non-doped layer, the emission intensity between bands can be further increased by doping the donor impurity as compared with the non-doped layer. When the acceptor impurity is doped, the peak wavelength can be shifted to the lower energy side by about 0.5 eV from the peak wavelength of interband light emission, but the full width at half maximum is widened. When both the acceptor impurity and the donor impurity are doped, the light emission intensity can be further increased as compared with the light emission intensity of the active layer doped only with the acceptor impurity. In particular, when an active layer doped with an acceptor impurity is formed, the conductivity type of the active layer is preferably doped with a donor impurity such as Si to be n-type.

As the second n-type cladding layer 234 and the first n-type cladding layer 235, a known n-type cladding layer material for LED can be used, and a single layer or a multilayer structure may be used. When the second n-type cladding layer 234 and the first n-type cladding layer 235 are formed of an n-type semiconductor having a band gap energy larger than that of the active layer 236, the second n-type cladding layer 234 and the first n-type cladding layer 234 are formed. A potential barrier against holes is formed between the mold cladding layer 235 and the active layer 236, and holes can be confined in the active layer 236. For example, the second n-type cladding layer 234 and the first n-type cladding layer 235 can be formed from n-type In _x Ga _1-x N (0 ≦ x <1). Is not limited to these.

As the first p-type cladding layer 237 and the second p-type cladding layer 238, a known p-type cladding layer material for LED can be used, and a single layer or a multilayer structure may be used. When the first p-type cladding layer 237 and the second p-type cladding layer 238 are formed of a p-type semiconductor having a band gap energy larger than that of the active layer 236, the first p-type cladding layer 237 and the second p-type cladding layer 238 are used. A potential barrier against electrons is formed between the mold cladding layer 238 and the active layer 236, and the electrons can be confined in the active layer 236. For example, the first p-type cladding layer 237 and the second p-type cladding layer 238 can be formed from Al _y Ga _1-y N (0 ≦ y ≦ 1). It is not limited to.

As the n-type contact layer 233, a known contact layer material for LED can be used. For example, as a layer for forming an electrode in contact with the second n-type clad layer 234 and the first n-type clad layer 235 An n-type contact layer 233 made of n-type GaN can be formed. It is also possible to form a p-type contact layer made of p-type GaN as a layer for forming an electrode in contact with the first p-type cladding layer 237 and the second p-type cladding layer 238. However, this p-type contact layer is not particularly required to be formed if the second n-type cladding layer 234 and the second p-type cladding layer 238 are formed of GaN. The n-type cladding layer 234 and the second p-type cladding layer 238) may be used as contact layers.

As a method for forming each of the layers used in the present embodiment, a known film forming process for LEDs can be used, but the present embodiment is not particularly limited thereto. For example, by using a vapor phase growth method such as MOVPE (metal organic vapor phase epitaxy), MBE (molecular beam vapor phase epitaxy), HDVPE (hydride vapor phase epitaxy), for example, sapphire (C plane, A plane, R plane), SiC (including 6H—SiC, 4H—SiC), spinel (MgAl ₂ O ₄ , especially its (111) plane), ZnO, Si, GaAs, or other oxide single crystal substrates ( It is possible to form on a substrate such as NGO.

(3) Third Embodiment FIG. 21 is a schematic sectional view showing an inorganic EL element substrate constituting a display device according to a third embodiment. The display device of this embodiment includes a phosphor substrate comprising a substrate on which a phosphor layer, a light distribution adjustment layer, a barrier, a light absorption layer, and the like are formed in the first to sixteenth embodiments of the light emitting device described above. And an inorganic EL element substrate (light source) 250 bonded on a phosphor substrate via a planarizing film or the like.

The inorganic EL element substrate 250 is generally composed of a substrate 251 and an inorganic EL element 252 provided on one surface 251a of the substrate 251.
The inorganic EL element 252 includes a first electrode 253, a first dielectric layer 254, a light emitting layer 255, a second dielectric layer 256, and a second electrode 257, which are sequentially stacked on one surface 251a of the substrate 251. Yes. The first electrode 253 and the second electrode 257 function as a pair as an anode or a cathode of the inorganic EL element 252. As the inorganic EL element 252, a known inorganic EL element such as an ultraviolet light emitting inorganic EL element or a blue light emitting inorganic EL element can be used, but the specific configuration is not limited to the above. Absent.

Hereinafter, although each structural member which comprises the inorganic EL element substrate 250, and its formation method are demonstrated concretely, this embodiment is not limited to these structural members and a formation method.

As the substrate 251, the same substrate as the substrate 211 constituting the organic EL element substrate 210 described above is used.

The first electrode 253 and the second electrode 257 function as a pair as an anode or a cathode of the inorganic EL element 252. That is, when the first electrode 253 is an anode, the second electrode 257 is a cathode, and when the first electrode 253 is a cathode, the second electrode 257 is an anode.

As the first electrode 253 and the second electrode 257, a metal such as aluminum (Al), gold (Au), platinum (Pt), nickel (Ni), and an oxide made of indium (In) and tin (Sn) (ITO), tin (Sn) oxide (SnO ₂ ), oxide (IZO) made of indium (In) and zinc (Zn), and the like can be cited as transparent electrode materials. It is not limited. A transparent electrode such as ITO is good for the electrode on the light extraction side, and a reflective electrode made of aluminum or the like is preferably used for the electrode on the opposite side to the light extraction direction.

The first electrode 253 and the second electrode 257 can be formed by using a known method such as an EB vapor deposition method, a sputtering method, an ion plating method, or a resistance heating vapor deposition method using the above materials. Is not limited to these forming methods. Moreover, the electrode formed by the photolithographic method and the laser peeling method can also be patterned as needed, and the patterned electrode can also be formed by combining with a shadow mask. The film thicknesses of the first electrode 253 and the second electrode 257 are preferably 50 nm or more. When the film thickness is less than 50 nm, the wiring resistance increases and the drive voltage may increase.

As the first dielectric layer 254 and the second dielectric layer 256, a known dielectric material for inorganic EL elements can be used. Examples of such a dielectric material include tantalum pentoxide (Ta ₂ O ₅ ), silicon oxide (SiO ₂ ), silicon nitride (Si ₃ N ₄ ), aluminum oxide (Al ₂ O ₃ ), aluminum titanate ( Examples include AlTiO ₃ ), barium titanate (BaTiO ₃ ), and strontium titanate (SrTiO ₃ ). However, the present embodiment is not limited to these dielectric materials. Further, the first dielectric layer 254 and the second dielectric layer 256 may have a single layer structure made of one type selected from the above dielectric materials, or may have a multilayer structure in which two or more types are stacked. Also good.
The film thicknesses of the first dielectric layer 254 and the second dielectric layer 256 are preferably about 200 to 500 nm.

As the light-emitting layer 255, a known light-emitting material for inorganic EL elements can be used. As such a light emitting material, for example, ZnF ₂ : Gd as an ultraviolet light emitting material, BaAl ₂ S ₄ : Eu, CaAl ₂ S ₄ : Eu, ZnAl ₂ S ₄ : Eu, Ba ₂ SiS ₄ as a blue light emitting material. : Ce, ZnS: Tm, SrS: Ce, SrS: Cu, CaS: Pb, (Ba, Mg) Al ₂ S ₄ : Eu, and the like, but this embodiment is not limited to these light emitting materials. Absent.
Further, the thickness of the light emitting layer 255 is preferably about 300 to 1000 nm.

As the configuration of the light source, the organic EL element substrate is exemplified in the first embodiment, the LED substrate is exemplified in the second embodiment, and the inorganic EL element substrate is exemplified in the third embodiment. In these structural examples, it is preferable to provide a sealing film or a sealing substrate for sealing a light emitting element such as an organic EL element, an LED, or an inorganic EL element.

The sealing film and the sealing substrate can be formed by a known sealing material and sealing method. Specifically, the sealing film can be formed by applying a resin on the surface opposite to the substrate constituting the light source by using a spin coat method, an ODF, a laminate method, or the like. Alternatively, after forming an inorganic film such as SiO, SiON, SiN, etc. by plasma CVD, ion plating, ion beam, sputtering, etc., resin is further added using spin coating, ODF, lamination, etc. A sealing film can be formed by coating, or a sealing substrate can be attached.

Such a sealing film or a sealing substrate can prevent entry of oxygen and moisture from the outside into the light-emitting element, thereby improving the life of the light source. Moreover, when joining a light source and a fluorescent substance board | substrate, it can also be made to adhere | attach with general ultraviolet curable resin, thermosetting resin, etc. In addition, when the light source is directly formed on the phosphor substrate, for example, a method of sealing an inert gas such as nitrogen gas or argon gas with a glass plate, a metal plate, or the like can be given. Furthermore, it is preferable to mix a hygroscopic agent such as barium oxide in the enclosed inert gas because deterioration of the organic EL element due to moisture can be more effectively reduced. However, this embodiment is not limited to these members and forming methods. In addition, when light is extracted from the side opposite to the substrate, it is necessary to use a light-transmitting material for both the sealing film and the sealing substrate.

(4) Fourth Embodiment FIG. 22 is a schematic sectional view showing a display device according to a fourth embodiment. 22, the same components as those of the light emitting device 30 illustrated in FIG. 3 and the organic EL element substrate 210 illustrated in FIG. 19 are denoted by the same reference numerals, and description thereof is omitted.
The display device 260 of the present embodiment has the same configuration as the substrate on which the phosphor layer, the light distribution adjusting layer, the barrier, the light absorption layer, and the like are formed in the first to sixteenth embodiments of the light emitting device described above. It is schematically composed of a phosphor substrate 261 and an active matrix driving type organic EL element substrate (light source) 262 bonded on the phosphor substrate 261 via a planarizing film.

In the organic EL element substrate 262, an active matrix driving method using TFTs is used as means for switching whether to irradiate each of the red pixel PR, the green pixel PG, and the blue pixel PB. When the organic EL element substrate 262 emits blue light, the blue pixel PB has a light scattering layer 263 that scatters blue light.

"Active matrix drive type organic EL element substrate"
Hereinafter, the active matrix driving type organic EL element substrate 262 will be described in detail. FIG. 23 is a schematic configuration diagram illustrating a display device including an organic EL element substrate. The organic EL element substrate 262 has a TFT 264 formed on one surface 211 a of the substrate 211. That is, the gate electrode 265 and the gate line 266 are formed on one surface 211a of the substrate 211, and the gate insulating film 267 is formed on the one surface 211a of the substrate 211 so as to cover the gate electrode 265 and the gate line 266. Has been. An active layer (not shown) is formed on the gate insulating film 267. A source electrode 268, a drain electrode 269, and a data line 270 are formed on the active layer, and covers the source electrode 268, the drain electrode 269, and the data line 270. As described above, the planarizing film 271 is formed.

Note that the planarization film 271 does not have to have a single layer structure, and may have a structure in which another interlayer insulating film and a planarization film are combined. Further, a contact hole 272 that penetrates the planarization film 271 or the interlayer insulating film and reaches the drain electrode 269 is formed, and the organic EL that is electrically connected to the drain electrode 269 via the contact hole 272 on the planarization film 271. A first electrode 213 of the element 212 is formed. The configuration of the organic EL element 212 is the same as that in the first embodiment.

The TFT 264 is formed in advance on one surface 211a of the substrate 211 before forming the organic EL element 212, and functions as a pixel switching element and an organic EL element driving element. The TFT 264 includes a known TFT, and can be formed using a known material, structure, and formation method. In this embodiment, a metal-insulator-metal (MIM) diode can be used instead of the TFT 264.

As the material of the active layer constituting the TFT 264, the same material as in the first embodiment described above is used. As a method for forming the active layer constituting the TFT 264, the same method as in the first embodiment described above is used.

The gate insulating film 267 included in the TFT 264 can be formed using a known material. As the gate insulating film 267, for example, PECVD method, SiO ₂ or the like to the SiO ₂ or polysilicon film formed by the LPCVD method or the like obtained by thermal oxidation. The data line 270, the gate line 266, the source electrode 268, and the drain electrode 269 included in the TFT 264 can be formed using a known conductive material. Examples of the material of the data line 270, the gate line 266, the source electrode 268, and the drain electrode 269 include tantalum (Ta), aluminum (Al), copper (Cu), and the like. The TFT 264 can be configured as described above, but the present embodiment is not limited to these materials, structures, and formation methods.

Examples of the interlayer insulating film used in the present embodiment are the same as those in the first embodiment described above. In addition, as a method for forming the interlayer insulating film, the same method as in the first embodiment described above can be used.

When light emitted from the organic EL element 212 is extracted from the side opposite to the substrate 211 (second electrode 215 side), external light is incident on the TFT 264 formed on one surface 211a of the substrate 211, and the TFT 264 is electrically connected. It is preferable to use a light-shielding insulating film having a light-shielding property for the purpose of preventing changes in the mechanical characteristics. In addition, the interlayer insulating film and the light-shielding insulating film can be used in combination. Examples of the material for the light-shielding insulating film include the same materials as those in the first embodiment described above.

In the display device 260, the TFT 264 formed on one surface 211a of the substrate 211, various wirings, electrodes, and the like form irregularities on the surface, and the irregularities cause defects in the organic EL element 212 (for example, the first electrode 213, There is a possibility that the second electrode 215 may be broken or disconnected, the organic EL layer 214 may be broken, the first electrode 213 and the second electrode 215 may be short-circuited, or the breakdown voltage may be reduced. In order to prevent these defects, it is desirable to provide a planarizing film 271 on the interlayer insulating film.

The planarization film 271 can be formed using a known material. Examples of the material for the planarizing film 271 include the same materials as those in the first embodiment described above.
Further, the planarization film 271 may have either a single layer structure or a multilayer structure.

Further, a sealing film 273 for sealing the organic EL element 212 is provided on the surface of the organic EL element 212 (surface facing the phosphor substrate 261).

Further, as shown in FIG. 20, the display device 260 includes a pixel portion 273, a gate signal side drive circuit 274, a data signal side drive circuit 275, a signal wiring 276, and a current supply line 277 formed on the organic EL element substrate 262. And a flexible printed wiring board (hereinafter sometimes abbreviated as “FPC”) 278 connected to the organic EL element substrate 262 and an external drive circuit 290.

The organic EL element substrate 262 is electrically connected via an FPC 279 to an external drive circuit 290 including a scanning line electrode circuit, a data signal electrode circuit, a power supply circuit and the like for driving the organic EL element 212. In the present embodiment, a switching circuit such as a TFT 264 is disposed in the pixel portion 274, and a data signal side driving circuit for driving the organic EL element 212 to a wiring such as a data line 270 and a gate line 266 to which the TFT 264 is connected. 276 and a gate signal side driving circuit 275 are connected to each other, and an external driving circuit 290 is connected to these driving circuits via a signal wiring 267. In the pixel portion 274, a plurality of gate lines 266 and a plurality of data lines 270 are disposed, and a TFT 264 is disposed at an intersection of the gate lines 266 and the data lines 270.

The organic EL element 212 is driven by a voltage-driven digital gradation method, and two TFTs, a switching TFT and a driving TFT, are arranged for each pixel. The driving TFT and the first electrode 213 of the organic EL element 212 Are electrically connected through a contact hole 272 formed in the planarizing film 271. In addition, a capacitor (not shown) for setting the gate potential of the driving TFT to a constant potential is arranged in one pixel so as to be connected to the gate electrode of the driving TFT. However, the present embodiment is not particularly limited to these, and the driving method may be the voltage driving digital gradation method described above or the current driving analog gradation method. The number of TFTs is not particularly limited, and the organic EL element 212 may be driven by the two TFTs described above. For the purpose of preventing variations in characteristics (mobility, threshold voltage) of the TFT 264, The organic EL element 212 may be driven using two or more TFTs each having a built-in compensation circuit in the pixel.

According to the display device of the present embodiment, the brightness does not change when viewed from any direction, the color does not change when viewed from any direction, and the power consumption can be reduced. A display device can be realized. In particular, in the present embodiment, since the active matrix driving type organic EL element substrate 262 is employed, a display device with excellent display quality can be realized. In addition, the light emission time of the organic EL element 212 can be extended as compared with passive driving, and the driving current for obtaining desired luminance can be reduced, so that power consumption can be reduced. Furthermore, since light is extracted from the side opposite to the organic EL element substrate 262 (phosphor substrate 261 side), the light emitting region can be expanded regardless of the formation region of the TFT, various wirings, etc., and the aperture ratio of the pixel Can be increased.

(5) Fifth Embodiment FIG. 24 is a schematic cross-sectional view showing a display device according to a fifth embodiment. 24, the same components as those of the light emitting device 30 shown in FIG. 3, the organic EL element substrate 210 shown in FIG. 19, and the display device 260 shown in FIG. To do.
The display device 300 of the present embodiment has the same configuration as that of the substrate on which the phosphor layer, the light distribution adjusting layer, the barrier, the light absorption layer, and the like are formed in the first to sixteenth embodiments of the light emitting device described above. A fluorescent substrate 301, an organic EL element substrate (light source) 302, and a liquid crystal element 303 are roughly configured.

The organic EL element 212 constituting the organic EL element substrate 302 is not divided for each pixel and functions as a planar light source common to all the pixels. Further, the liquid crystal element 303 is configured to be able to control the voltage applied to the liquid crystal layer for each pixel using a pair of electrodes, and to control the transmittance of light emitted from the entire surface of the organic EL element 212 for each pixel. . In other words, the liquid crystal element 303 has a function as an optical shutter that selectively transmits light from the organic EL element substrate 302 for each pixel.

A known liquid crystal element can be used as the liquid crystal element 303. The liquid crystal element 303 includes, for example, a pair of

polarizing plates

311 and 312,

transparent electrodes

313 and 314,

alignment films

315 and 316, and a substrate 317, and a liquid crystal 318 is sandwiched between the

alignment films

315 and 316. It has a structure.

Further, an optically anisotropic layer is provided between the liquid crystal cell and one of the

polarizing plates

311 and 312, or an optical difference is provided between both the liquid crystal cell and the

polarizing plates

311 and 312. An isotropic layer may be provided. In the display device 300, a polarizing plate is preferably provided on the light extraction side.

As the

polarizing plates

311 and 312, a combination of a conventional linear polarizing plate and a λ / 4 plate can be used. By providing the

polarizing plates

311 and 312, reflection of external light from the electrodes of the display device 300 and reflection of external light on the surface of the substrate or the sealing substrate can be prevented, and the contrast of the display device 300 can be improved. it can. In addition, as the

polarizing plates

311 and 312, those having an extinction ratio of 10,000 or more at wavelengths of 435 nm or more and 480 nm or less are suitably used.

The type of liquid crystal cell is not particularly limited, and can be appropriately selected according to the purpose. Examples of the liquid crystal cell include TN mode, VA mode, OCB mode, IPS mode, ECB mode, and the like.
The liquid crystal element 303 may be passively driven or may be actively driven using a switching element such as a TFT.

According to the display device of the present embodiment, the brightness does not change when viewed from any direction, the color does not change when viewed from any direction, and the power consumption can be reduced. A display device can be realized. Further, in the present embodiment, power consumption can be further reduced by combining pixel switching by the liquid crystal element 303 and the organic EL element substrate 302 that functions as a planar light source.

(6) Sixth Embodiment FIG. 25 is a schematic cross-sectional view showing a sixth embodiment of the display device according to the present invention. 25, the same components as those of the light-emitting device 30 illustrated in FIG. 3 and the liquid crystal element 303 illustrated in FIG. 24 are denoted by the same reference numerals, and description thereof is omitted.
The display device 400 of this embodiment has the same configuration as the substrate on which the phosphor layer, the light distribution adjusting layer, the barrier, the light absorption layer, and the like are formed in the first to sixteenth embodiments of the light emitting device described above. A fluorescent substrate 301, a liquid crystal element 303, and a backlight unit 401 are roughly configured.

The backlight unit 401 has a light source disposed on the bottom surface or side surface of the backlight unit 401. When the light source is disposed on the side surface of the backlight unit 401, the backlight unit 401 includes, for example, a reflection sheet, a light source, a light guide plate, a first diffusion sheet, a prism sheet, and a second diffusion sheet. Further, a brightness enhancement film may be disposed between the backlight unit 401 and the backlight side polarizing plate 311.
Here, as the backlight unit 401, the light source 402 disposed on the side surface of the backlight unit 401, the light guide plate 403 that guides light from the light source 402 in the surface direction of the liquid crystal element 303, and the liquid crystal from the light guide plate 403 to the liquid crystal What was roughly comprised from the brightness enhancement film 404 which injects light into the element 303 efficiently was illustrated.

According to the display device 400, an excellent display device that does not change brightness when viewed from any direction, does not change color when viewed from any direction, and is capable of reducing power consumption. realizable.
Further, in the present embodiment, power consumption can be further reduced by combining pixel switching by the liquid crystal element 303 and the backlight unit 401 that functions as a planar light source.

"mobile phone"
The display devices of the first to fifth embodiments described above can be applied to, for example, the mobile phone shown in FIG. The cellular phone 310 includes a main body 311, a display unit 312, an audio input unit 313, an audio output unit 314, an antenna 315, an operation switch 316, and the like. As the display unit 312, the display devices of the first to fifth embodiments described above can be suitably applied. By applying the display devices of the first to fifth embodiments described above to the display unit 312 of the mobile phone 310, a high-luminance video can be displayed with low power consumption.

"Flat TV"
The display devices of the first to fifth embodiments described above can be applied to, for example, a thin television shown in FIG. The thin television 320 includes a main body cabinet 321, a display unit 322, speakers 323, a stand 324, and the like. As the display unit 322, the display devices of the first to fifth embodiments described above can be suitably applied. By applying the display device of the first to fifth embodiments to the display unit 322 of the flat-screen television 320, the brightness does not change when viewed from any direction with low power consumption, and the viewing is performed from any direction. Even so, a display that does not change in color can be realized.

"Lighting device"
(1) First Embodiment FIG. 28 is a schematic sectional view showing a lighting device according to the first embodiment.
The illumination device 330 of this embodiment includes an optical film 331, a phosphor substrate 332, an organic EL element 333, a thermal diffusion sheet 334, a sealing substrate 335, a sealing resin 336, a heat dissipation material 337, and a drive. A circuit 338, a wiring 339, and a hook ceiling 340 are roughly configured. The organic EL element 333 is generally composed of an anode 341, an organic EL layer 342, and a cathode 343. The light distribution adjustment layer in the phosphor substrate 322 may be formed between the substrate and the optical film or on the optical film.
In the lighting device 330, the phosphor substrate 332 is the same as the substrate on which the phosphor layer, the light distribution adjusting layer, the barrier, the light absorption layer, and the like are formed in the first to sixteenth embodiments of the light emitting device described above. Therefore, according to the display device of this embodiment, the brightness does not change even when viewed from any direction, and further, an excellent illumination device capable of reducing power consumption Can be realized.

(2) Second Embodiment FIG. 29 is a schematic sectional view showing a lighting device according to a second embodiment.
The illuminating device 250 includes a light emitting device 253 that is roughly composed of an excitation light source 281 that emits excitation light and a phosphor substrate 252.
The phosphor substrate 252 is formed on the substrate, an excitation light source that emits excitation light, a substrate that is disposed opposite to the excitation light source and on which a phosphor layer that is excited by the excitation light and emits fluorescence is formed. A light distribution adjusting layer that changes the emission direction of fluorescence emitted from at least the phosphor layer, and a light-reflective barrier on at least one side surface of the phosphor layer along a stacking direction with the substrate; The phosphor layer generally includes a wavelength selective transmission / reflection layer formed on an incident surface side on which excitation light is incident.

Examples of the excitation light source include those similar to the excitation light source in the first to sixteenth embodiments of the light emitting device described above. Examples of the substrate include the same substrates as those in the first to sixteenth embodiments of the light emitting device described above.

Examples of the phosphor layer include those similar to the phosphor layer in the first to sixteenth embodiments of the light emitting device described above. Examples of the barrier include the same barriers as those in the first to sixteenth embodiments of the light emitting device described above. Examples of the light scattering layer include the same light scattering layers as those in the first to sixteenth embodiments of the light emitting device described above. Examples of the wavelength selective transmission / reflection layer include those similar to the wavelength selective transmission / reflection layer in the first to sixteenth embodiments of the light-emitting device described above.

With reference to FIG. 29, the light emission in the illuminating device 250 is demonstrated.
In the illumination device 250, when excitation light is incident on the phosphor layer from the excitation light source, light is emitted from the phosphor layer isotropically, that is, with equal energy in any direction. The luminance viewing angle characteristic of this light is such that the larger the viewing angle is, the larger the viewing angle is between 0 ° and 80 °, since the viewing angle (the angle formed by the surface perpendicular to the light emitting surface and the viewing direction) is related to the solid angle. Has a high profile. Then, this light enters the light distribution adjustment layer through the substrate, and light is scattered in the light distribution adjustment layer to change the traveling direction of the light. At this time, the light path length in the light distribution adjustment layer is longer in the latter case for light incident perpendicularly to the surface of the light distribution adjustment layer and light incident in an oblique direction. Therefore, the latter light with respect to the former is often scattered in the light distribution adjusting layer.

In other words, a light emission profile in which the luminance increases as the viewing angle increases is changed to a light emission profile in which at least the luminance in the 0 ° direction is equal to or higher than the luminance in the oblique direction through the light distribution adjustment layer. Can do. As a result, it is possible to obtain an illumination device that does not change in brightness when viewed from any direction. In addition, in this configuration, since a light-reflective barrier is provided on the side surface of the phosphor layer, out of the fluorescence emitted from the phosphor layer, the fluorescent component reflected at the interface of the substrate and the light of the phosphor layer The fluorescent component that emits light on the side opposite to the extraction side is reflected by the side surface of the light-reflective barrier, and is recycled again to a component that can be extracted to the substrate side. That is, by providing a light-reflective barrier on the side surface of the phosphor layer, it is possible to efficiently extract the fluorescent component emitted from the phosphor layer to the outside.

Further, in this structure, since the wavelength selective transmission / reflection layer is provided on the incident surface side on which the excitation light is incident in the phosphor layer, the phosphor layer emits light on the side opposite to the light extraction side (back side). The fluorescent component is reflected at the interface between the phosphor layer and the wavelength selective transmission / reflection layer, and can be effectively extracted to the outside as light emission on the light extraction side. That is, by providing the wavelength selective transmission / reflection layer on the incident surface side where the excitation light is incident on the phosphor layer, the fluorescent component emitted from the phosphor layer can be extracted to the outside very efficiently.

Hereinafter, although an example of the present invention will be described more specifically with reference to examples and comparative examples, the present invention is not limited to the following examples.

"Comparative example"
A 0.7 mm thick glass substrate was washed with water, then subjected to pure water ultrasonic cleaning for 10 minutes, acetone ultrasonic cleaning for 10 minutes, and isopropyl alcohol vapor cleaning for 5 minutes, and dried at 100 ° C. for 1 hour. Next, a green phosphor layer having a thickness of 2 μm was formed on one surface of the glass substrate.
Here, in order to form a green phosphor layer, 100 g of a toluene solution in which 10 wt% of PMMA was dissolved was added to 0.1 g of Coumarin 545T, and the mixture was heated and stirred to prepare a coating solution for forming a green phosphor.

Next, the prepared green phosphor-forming coating solution was applied onto the substrate using a spinner. Subsequently, it was dried by heating in a vacuum oven (100 ° C., 10 mmHg) for 4 hours to form a green phosphor layer with a film thickness of 2 μm to obtain a phosphor substrate.

After that, light of 460 nm is incident from the back side (film surface side) of the phosphor substrate of the comparative example using a self-made blue directional surface light source (backlight) equipped with a commercially available blue LED as incident light, and is emitted from the substrate. When observing the characteristics of the light, it was confirmed that the one viewed from an oblique direction was brighter than the front direction.

In addition, using a commercially available luminance viewing angle measuring device (Ez-contrast: manufactured by ELDIM), a blue directional surface light source (backlight) is used as incident light and light at 460 nm is used as the back surface (film) of the phosphor substrate of the comparative example. The luminance viewing angle characteristics at 25 ° C. of the fluorescence extracted from the substrate side when it was incident from the (surface side) were measured. As a result, the relative luminance value (L ₆₀ / L ₀ ) in the direction of the viewing angle 60 ° with respect to the luminance value of the viewing angle 0 ° (normal direction) of the blue directional surface light source as incident light was 0.03. On the other hand, the relative luminance value (L ₆₀ / L ₀ ) in the direction of the viewing angle 60 ° with respect to the luminance value of the viewing angle 0 ° (normal direction) of the fluorescence emitted from the phosphor substrate was 1.10. .

In addition, using a commercially available all-light measuring device (integrating sphere) (Half Moon: manufactured by Otsuka Electronics Co., Ltd.), 460 nm blue light is incident from the back surface of the phosphor substrate, and is reflected on the front surface of the phosphor substrate. The light extraction efficiency was measured. As a result, the light extraction efficiency was 12.0%.

"Example 1"
In the same manner as in the comparative example, a green phosphor layer having a thickness of 2 μm was formed on one surface of the glass substrate. Here, in order to form a green phosphor layer, 100 g of a toluene solution in which 10% by weight of PMMA was dissolved was added to 0.1 g of Coumarin 545T, and the mixture was heated and stirred to prepare a coating solution for forming a green phosphor.

Next, a light distribution adjusting layer was formed on one surface of the glass substrate (the surface opposite to the surface on which the phosphor layer was formed). Here, in order to form the light distribution adjusting layer, first, as a binder for dispersing the light scattering particles, Sekisui Plastics Co., Ltd., a resin “LuxPrint 8155” manufactured by Teijin DuPont Co., Ltd. having an average particle size of 4 μm ) Made techpolymer "SBX-4": 3.59g and Titanium Chemical Industry Co., Ltd. titanium oxide "R-25": 1.27g with an average particle size of 200nm, and after thorough mixing for 30 minutes in an automatic mortar, Using a dispersion stirrer “Filmix 40-40” manufactured by Primix Co., Ltd., the mixture was pre-stirred for 15 minutes at a stirring speed of 6,000 rpm under an open system at room temperature.

Next, a 15 μm thick light distribution adjusting layer was formed on one surface of the glass substrate using a commercially available spin coater. Next, it is heated and dried in a vacuum oven (200 ° C. condition) for 15 minutes to form a light distribution adjustment layer, a glass substrate, a phosphor layer formed on one surface thereof, and a light distribution adjustment formed on the opposite surface. A phosphor substrate of Example 1 consisting of layers was obtained.

Thereafter, light of 460 nm is incident from the back surface (phosphor layer side) of the phosphor substrate of Example 1 by using a self-made blue directional surface light source (backlight) mounted with a commercially available blue LED as incident light, and the light distribution. When the characteristics of the light emitted from the adjustment layer were observed, it was confirmed that there was no significant difference in brightness from any direction.

Further, using a commercially available luminance viewing angle measuring device (Ez-contrast: manufactured by ELDIM), a blue directional surface light source (backlight) was used as incident light, and light of 460 nm was emitted from the rear surface of the phosphor substrate of Example 1 When the light was incident from the phosphor layer side), the luminance viewing angle characteristics at 25 ° C. of the fluorescence extracted from the light distribution adjusting layer were measured. As a result, the relative luminance value (L ₆₀ / L ₀ ) in the direction of 60 ° viewing angle with respect to the luminance value in the viewing angle 0 ° (normal direction) of the blue directional surface light source as incident light was 0.03. On the other hand, the relative luminance value (L ₆₀ / L ₀ ) in the direction of the viewing angle 60 ° with respect to the luminance value of the viewing angle 0 ° (normal direction) of the fluorescence emitted from the phosphor substrate was 0.85. .

In addition, using a commercially available all-light measuring device (integrating sphere) (Half Moon: manufactured by Otsuka Electronics Co., Ltd.), 460 nm blue light is incident from the back surface of the phosphor substrate, and is reflected on the front surface of the phosphor substrate. The light extraction efficiency was measured. As a result, the light extraction efficiency was 9.2%.

"Example 2"
In the same manner as in Example 1, a green phosphor layer having a thickness of 2 μm was formed on one surface of the glass substrate. Here, in order to form a green phosphor layer, 100 g of a toluene solution in which 10% by weight of PMMA was dissolved was added to 0.1 g of Coumarin 545T, and the mixture was heated and stirred to prepare a coating solution for forming a green phosphor.

Next, a light distribution adjusting layer was formed on one surface of the glass substrate (the surface opposite to the surface on which the phosphor layer was formed). Here, in order to form the light distribution adjusting layer, first, as a binder for dispersing the light scattering particles, Sekisui Plastics Co., Ltd. having an average particle diameter of 4 μm on Teijin DuPont's resin “LuxPrint 8155”: 30 g. ) Techpolymer "SBX-4": 3.59g and titanium oxide "R-42": 0.63g made by Sakai Chemical Industry Co., Ltd. with an average particle size of 290nm were added and thoroughly mixed for 30 minutes in an automatic mortar. Thereafter, the mixture was pre-stirred for 15 minutes at a stirring speed of 6,000 rpm under an open system room temperature using a dispersion stirring apparatus “Filmix 40-40 type” manufactured by Primix Co., Ltd.

Next, a 5 μm thick light distribution adjusting layer was formed on one surface of the glass substrate using a commercially available spin coater. Next, heat drying for 15 minutes in a vacuum oven (200 ° C condition) to form a light distribution adjustment layer, a glass substrate, a phosphor layer formed on one side thereof, and a light distribution adjustment formed on the opposite side. A phosphor substrate of Example 2 consisting of layers was obtained.

Thereafter, light of 460 nm was incident from the back surface (phosphor layer side) of the phosphor substrate of Example 2 using a self-made blue directional surface light source (backlight) equipped with a commercially available blue LED as incident light, and the light distribution. When the characteristics of the light emitted from the adjustment layer were observed, it was confirmed that there was no significant difference in brightness from any direction.

In addition, using a commercially available luminance viewing angle measuring device (Ez-contrast: manufactured by ELDIM), a blue directional surface light source (backlight) was used as incident light, and light of 460 nm was emitted from the rear surface of the phosphor substrate of Example 2 ( When the light was incident from the phosphor layer side), the luminance viewing angle characteristics at 25 ° C. of the fluorescence extracted from the light distribution adjusting layer were measured. As a result, the relative luminance value (L ₆₀ / L ₀ ) in the direction of 60 ° viewing angle with respect to the luminance value in the viewing angle 0 ° (normal direction) of the blue directional surface light source as incident light was 0.03. On the other hand, the relative luminance value (L ₆₀ / L ₀ ) in the direction of the viewing angle of 60 ° with respect to the luminance value of the viewing angle of 0 ° (normal direction) of the fluorescence emitted from the phosphor substrate was 0.82. .

In addition, using a commercially available all-light measuring device (integrating sphere) (Half Moon: manufactured by Otsuka Electronics Co., Ltd.), 460 nm blue light is incident from the back surface of the phosphor substrate, and is reflected on the front surface of the phosphor substrate. The light extraction efficiency was measured. As a result, the light extraction efficiency was 11.9%.

"Example 3"
A barrier was formed on the glass substrate. Hereinafter, the method of forming the barrier will be described in detail.
First, epoxy resin (refractive index: 1.59), acrylic resin (refractive index: 1.49), rutile-type titanium oxide (refractive index: 2.71, particle size 250 nm), photopolymerization initiator and aromatic A negative photosensitive resist was prepared by stirring and mixing a white photosensitive composition comprising a system solvent. Next, a negative resist was applied on the glass substrate by a spin coater method.
Then, it prebaked at 80 degreeC for 10 minute (s), and formed the coating film with a film thickness of 50 micrometers.

After covering this coating film with a mask capable of forming a desired image pattern, the coating film was irradiated with i-line (300 mJ / cm ² ) and exposed. Next, development was performed using an alkaline developer to obtain a pixel pattern structure having a barrier. Next, using a hot air circulation drying oven, post-baking was performed at 140 ° C. for 60 minutes to form a barrier partitioning the pixels.

Next, a phosphor layer was formed in the opening surrounded by the barrier. Here, a phosphor layer having a thickness of 2 μm was formed in the opening by a dispenser method using the same phosphor material as in Example 2.

Next, a light distribution adjusting layer having a thickness of 5 μm was formed on one surface of the glass substrate (the surface opposite to the surface on which the phosphor layer was formed) using the same light scattering material as in Example 2. Next, it is heated and dried in a vacuum oven (200 ° C. condition) for 15 minutes, a light scattering layer is formed, a glass substrate, a phosphor layer formed on one surface thereof, and a light distribution adjustment layer formed on the other surface thereof Thus, a phosphor substrate of Example 3 consisting of a barrier formed on the side surface of the phosphor layer was obtained.

Further, using a commercially available luminance viewing angle measuring device (Ez-contrast: manufactured by ELDIM), a blue directional surface light source (backlight) was used as incident light, and light of 460 nm was emitted from the rear surface of the phosphor substrate of Example 1 When the light was incident from the phosphor layer side), the luminance viewing angle characteristics at 25 ° C. of the fluorescence extracted from the light distribution adjusting layer were measured. As a result, the relative luminance value (L ₆₀ / L ₀ ) in the direction of 60 ° viewing angle with respect to the luminance value in the viewing angle 0 ° (normal direction) of the blue directional surface light source as incident light was 0.03. On the other hand, the relative luminance value (L ₆₀ / L ₀ ) in the direction of the viewing angle 60 ° with respect to the luminance value of the viewing angle 0 ° (normal direction) of the fluorescence emitted from the phosphor substrate was 0.86. .

In addition, using a commercially available all-light measuring device (integrating sphere) (Half Moon: manufactured by Otsuka Electronics Co., Ltd.), 460 nm blue light is incident from the back surface of the phosphor substrate, and is reflected on the front surface of the phosphor substrate. The light extraction efficiency was measured. As a result, the light extraction efficiency was 15.3%.

"Example 4"
In the same manner as in Example 3, a barrier layer and a phosphor layer having a thickness of 2 μm were formed on the opening on the glass substrate.

Next, titanium oxide (TiO ₂ : refractive index = 2.30) and silicon oxide (SiO ₂ : refractive index =) are formed as a wavelength selective transmission / reflection layer on the surface on the phosphor layer where excitation light is incident. A dielectric multilayer film produced by alternately forming six layers of 1.47) by EB vapor deposition was formed to a thickness of 100 nm by sputtering.

Finally, a light distribution adjusting layer having a film thickness of 5 μm was formed on one surface of the glass substrate (the surface opposite to the surface on which the phosphor layer was formed) using the same light scattering material as in Example 3.
Next, heat drying for 15 minutes in a vacuum oven (200 ° C condition) to form a light distribution adjustment layer, a glass substrate, a phosphor layer formed on one side thereof, and a light distribution adjustment formed on the opposite side. Thus, a phosphor substrate of Example 4 was obtained, comprising a layer, a barrier formed on the side surface of the phosphor layer, and a wavelength selective transmission / reflection layer formed on one surface of the phosphor layer on the excitation light incident surface side.

Thereafter, light of 460 nm was incident from the back surface (phosphor layer side) of the phosphor substrate of Example 4 using a self-made blue directional surface light source (backlight) equipped with a commercially available blue LED as incident light, and the light distribution When the characteristics of the light emitted from the adjustment layer were observed, it was confirmed that there was no significant difference in brightness from any direction.

Further, using a commercially available luminance viewing angle measuring device (Ez-contrast: manufactured by ELDIM), a blue directional surface light source (backlight) is used as incident light, and light of 460 nm is emitted from the rear surface of the phosphor substrate of Example 4 ( When the light was incident from the phosphor layer side), the luminance viewing angle characteristic at 25 ° C. of the fluorescence extracted from the light distribution adjusting layer was measured. As a result, the relative luminance value (L ₆₀ / L ₀ ) in the direction of 60 ° viewing angle with respect to the luminance value in the viewing angle 0 ° (normal direction) of the blue directional surface light source as incident light was 0.03. On the other hand, the relative luminance value (L ₆₀ / L ₀ ) in the direction of the viewing angle 60 ° with respect to the luminance value of the viewing angle 0 ° (normal direction) of the fluorescence emitted from the phosphor substrate was 0.85. .

In addition, using a commercially available all-light measuring device (integrating sphere) (Half Moon: manufactured by Otsuka Electronics Co., Ltd.), 460 nm blue light is incident from the back surface of the phosphor substrate, and is reflected on the front surface of the phosphor substrate. The light extraction efficiency was measured. As a result, the light extraction efficiency was 21.2%.

"Example 5"
A low refractive index layer having a film thickness of 1 μm was formed on one surface of the same glass substrate as in the comparative example by spin coating. As a material for the low refractive index layer, “TPIR-414 T-3” manufactured by Tokyo Ohka Kogyo Co., Ltd. having a refractive index of about 1.2 to 1.3 was used.

Next, in the same manner as in Example 4, a barrier and a phosphor layer having a thickness of 2 μm were formed on the opening of the barrier on the low refractive index layer.

Next, a low refractive index layer having a thickness of 1 μm was formed on the entire surface of the phosphor layer by spin coating on the entire surface on the side on which excitation light is incident. As a material for the low refractive index layer, “TPIR-414 T-3” manufactured by Tokyo Ohka Kogyo Co., Ltd. having a refractive index of about 1.2 to 1.3 was used.

Next, titanium oxide (TiO ₂ : refractive index = 2.30) and silicon oxide (SiO ₂ : refractive index = 1.47) are deposited on one surface of the low refractive index layer as a wavelength selective transmission / reflection layer by EB deposition. A dielectric multilayer film produced by alternately forming six layers by the method was formed to a thickness of 100 nm by the sputtering method.

Finally, a light distribution adjusting layer having a film thickness of 5 μm was formed on one surface of the glass substrate (the surface opposite to the surface on which the phosphor layer was formed) using the same light scattering material as in Example 4. Next, it is heated and dried in a vacuum oven (200 ° C. condition) for 15 minutes to form a light distribution adjustment layer, a glass substrate, a phosphor layer formed on one surface thereof, and a light distribution adjustment formed on the opposite surface. Layer, a barrier formed on the side surface of the phosphor layer, a wavelength selective transmission / reflection layer formed on one surface of the phosphor layer on the excitation light incident surface side, and a low refractive index layer formed on both sides of the phosphor layer A phosphor substrate of Example 5 consisting of

Thereafter, light of 460 nm is incident from the back surface (phosphor layer side) of the phosphor substrate of Example 5 using a self-made blue directional surface light source (backlight) equipped with a commercially available blue LED as incident light, and the light distribution is made. When the characteristics of the light emitted from the adjustment layer were observed, it was confirmed that there was no significant difference in brightness from any direction.

In addition, using a commercially available luminance viewing angle measuring device (Ez-contrast: manufactured by ELDIM), light of 460 nm was incident on a blue directional surface light source (backlight) as the incident light, and the back surface of the phosphor substrate of Example 5 ( When the light was incident from the phosphor layer side), the luminance viewing angle characteristic at 25 ° C. of the fluorescence extracted from the light distribution adjusting layer was measured. As a result, the relative luminance value (L ₆₀ / L ₀ ) in the direction of 60 ° viewing angle with respect to the luminance value in the viewing angle 0 ° (normal direction) of the blue directional surface light source as incident light was 0.03. On the other hand, the relative luminance value (L ₆₀ / L ₀ ) in the direction of the viewing angle 60 ° with respect to the luminance value of the viewing angle 0 ° (normal direction) of the fluorescence emitted from the phosphor substrate was 0.85. .

In addition, using a commercially available all-light measuring device (integrating sphere) (Half Moon: manufactured by Otsuka Electronics Co., Ltd.), 460 nm blue light is incident from the back surface of the phosphor substrate, and is reflected on the front surface of the phosphor substrate. The light extraction efficiency was measured. As a result, the light extraction efficiency was 21.2%. Table 1 shows the relative luminance ratio, total light transmittance, and comparison results between each example and Comparative Example 1 in the comparative examples and the phosphor substrates of Examples 1 to 5.

“Example 6” [Blue organic EL + phosphor method]
In the same manner as in Example 5, a low refractive index layer having a thickness of 1 μm was formed on a glass substrate by spin coating. As a material for the low refractive index layer, “TPIR-414 T-3” manufactured by Tokyo Ohka Kogyo Co., Ltd. having a refractive index of about 1.2 to 1.3 was used.
Next, a barrier (light scattering film) was formed on the low refractive index layer. Hereinafter, the method of forming the barrier will be described in detail.
First, epoxy resin (refractive index: 1.59), acrylic resin (refractive index: 1.49), rutile-type titanium oxide (refractive index: 2.71, particle size 250 nm), photopolymerization initiator and aromatic A negative photosensitive resist was prepared by stirring and mixing a white photosensitive composition comprising a system solvent. Next, a negative resist was applied on the glass substrate by a spin coater method.
Then, it prebaked at 80 degreeC for 10 minute (s), and formed the coating film with a film thickness of 50 micrometers.

Next, a red phosphor layer, a green phosphor layer, and a blue scatterer layer were formed in the opening surrounded by the barrier. Hereinafter, a method for forming the red phosphor layer, the green phosphor layer, and the blue scatterer layer will be described in detail.

In order to form a red phosphor layer, first, 100 g of a dichlorobenzene solution in which 10 wt% polystyrene is dissolved is added to 0.01 g of red phosphor rhodamine 6G, and hollow silica having a refractive index of 1.21 and a particle diameter of 20 nm. Was added, and the mixture was heated and stirred to prepare a red phosphor-forming coating solution.

Next, the produced red phosphor-forming coating solution was applied in a pattern to regions partitioned by the partition walls by a dispenser technique. Subsequently, it was dried by heating in a vacuum oven (200 ° C., 10 mmHg) for 4 hours, and a red phosphor layer was patterned with a film thickness of 5 μm.

To form a green phosphor layer, first, 100 g of a dichlorobenzene solution in which 10 wt% of polystyrene is dissolved is added to 0.01 g of coumarin, and then 40 g of hollow silica having a refractive index of 1.21 and a particle diameter of 20 nm is added. Then, the mixture was heated and stirred to produce a green phosphor forming coating solution. Next, the produced green phosphor forming coating solution was applied in a pattern to the area partitioned by the partition wall 103 by a dispenser technique. Subsequently, it was dried by heating in a vacuum oven (200 ° C., 10 mmHg) for 4 hours, and a green phosphor layer was patterned with a film thickness of 5 μm.

In order to form a blue scatterer layer, first, as a binder for dispersing light scattering particles, a resin “LuxPrint 8155” manufactured by Teijin DuPont Co., Ltd .: 30 g, Sekisui Plastics Co., Ltd. Polymer "SBX-4": 3.59 g and titanium oxide "R-25": 1.27 g manufactured by Sakai Chemical Industry Co., Ltd. with an average particle size of 200 nm are added and thoroughly mixed for 30 minutes in an automatic mortar. Using a dispersion stirrer “Filmix 40-40” manufactured by Co., Ltd., the mixture was pre-stirred for 15 minutes at a stirring speed of 6,000 rpm under an open system room temperature to obtain a coating solution for forming a blue light scattering layer. .

Next, the prepared blue light scattering layer forming coating solution was applied in a pattern to regions partitioned by the partition walls by a dispenser technique. Subsequently, it was dried by heating in a vacuum oven (200 ° C., 10 mmHg) for 4 hours to form a blue firefly scatterer layer with a film thickness of 5 μm.

Next, a low refractive index layer having a thickness of 1 μm was formed on the entire surface of the red phosphor layer, the green phosphor layer, and the blue scatterer layer on the side where the excitation light is incident by spin coating. As a material for the low refractive index layer, “TPIR-414 T-3” manufactured by Tokyo Ohka Kogyo Co., Ltd. having a refractive index of about 1.2 to 1.3 was used.

Next, titanium oxide (TiO ₂ : refractive index = 2.30) and silicon oxide (SiO ₂ : refractive index = 1.47) are deposited on one surface of the low refractive index layer as a wavelength selective transmission / reflection layer by EB deposition. A dielectric multilayer film produced by alternately forming six layers by the method was formed to a thickness of 100 nm by a sputtering method.

Next, a light distribution adjusting layer was formed on one surface of the glass substrate (the surface opposite to the surface on which the phosphor layer was formed). Here, in order to form the light distribution adjusting layer, first, as a binder for dispersing the light scattering particles, Sekisui Plastics Co., Ltd. having an average particle diameter of 4 μm on Teijin DuPont's resin “LuxPrint 8155”: 30 g. ) Techpolymer “SBX-4”: 3.59 g and titanium oxide “R-42”: 0.63 g manufactured by Sakai Chemical Industry Co., Ltd. with an average particle size of 290 nm were added and thoroughly mixed for 30 minutes in an automatic mortar. Thereafter, the mixture was pre-stirred for 15 minutes at a stirring speed of 6,000 rpm under an open system room temperature using a dispersion stirring apparatus “Filmix 40-40 type” manufactured by Primix Co., Ltd.

Next, a 5 μm thick light distribution adjusting layer was formed on one surface of the glass substrate using a commercially available spin coater. Next, it is heated and dried in a vacuum oven (200 ° C. condition) for 15 minutes to form a light distribution adjustment layer, a glass substrate, a phosphor layer formed on one surface thereof, and a light distribution adjustment formed on the opposite surface. A phosphor substrate of Example 6 was obtained comprising a layer, a barrier formed on the side surface of the phosphor layer, and a wavelength selective transmission / reflection layer formed on one surface of the phosphor layer on the excitation light incident surface side.

On the other hand, a reflective electrode having a thickness of 100 nm made of silver is formed on a glass substrate having a thickness of 0.7 mm by a sputtering method, and a 20 nm-thick indium-tin oxide film is formed on the reflective electrode by a sputtering method. A first electrode (anode) was formed by depositing an object (ITO). Thereafter, the first electrode was patterned into 90 stripes with a width of 160 μm and a pitch of 200 μm by a conventional photolithography method.

Next, 200 nm of SiO ₂ was laminated on the first electrode by sputtering, and patterned to cover only the edge portion of the first electrode by conventional photolithography. Here, a short side of 10 μm from the end of the first electrode is covered with SiO ₂ . This was washed with water, subjected to pure water ultrasonic cleaning for 10 minutes, acetone ultrasonic cleaning for 10 minutes, and isopropyl alcohol vapor cleaning for 5 minutes, and dried at 120 ° C. for 1 hour.

Next, the substrate on which the first electrode is formed is fixed to a substrate holder in an in-line type resistance heating vapor deposition apparatus, and the pressure is reduced to a vacuum of 1 × 10 ⁻⁴ Pa or less to form an organic EL layer including an organic light emitting layer. Each layer was formed. Hereinafter, the formation method of each layer which comprises an organic EL layer is demonstrated in detail.
First, 1,1-bis-di-4-tolylamino-phenyl-cyclohexane (TAPC) was used as a hole injection material, and a hole injection layer having a thickness of 100 nm was formed by resistance heating vapor deposition. Next, N, N′-di-1-naphthyl-N, N′-diphenyl-1,1′-biphenyl-1,1′-biphenyl-4,4′-diamine (NPD) is used as a hole transport material. A hole transport layer having a thickness of 40 nm was formed by resistance heating vapor deposition.

Next, a blue organic light emitting layer (thickness: 30 nm) was formed at a desired pixel position on the hole transport layer. This blue organic light-emitting layer comprises 1,4-bis-triphenylsilyl-benzene (UGH-2) (host material) and bis [(4,6-difluorophenyl) -pyridinato-N, C2 ′] picolinate iridium (III) (FIrpic) (blue phosphorescent dopant) was co-deposited at a deposition rate of 1.5 Å / sec and 0.2 Å / sec, respectively.

Next, a hole blocking layer (thickness: 10 nm) was formed on the organic light emitting layer using 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline (BCP). Next, an electron transport layer (thickness: 30 nm) was formed on the hole blocking layer using tris (8-hydroxyquinoline) aluminum (Alq ₃ ). Next, an electron injection layer (thickness: 0.5 nm) was formed on the electron transport layer using lithium fluoride (LiF).
Through the above processing, each layer constituting the organic EL layer was formed.

Thereafter, a semitransparent electrode was formed as the second electrode.
First, the substrate was fixed in a metal vapor deposition chamber, and the shadow mask for forming the translucent electrode was aligned with the substrate. As the shadow mask, a mask provided with an opening so that the second electrode can be formed in a stripe shape having a width of 500 μm and a pitch of 600 μm in a direction facing the stripe of the first electrode.

Next, magnesium and silver are co-deposited on the surface of the electron injection layer by vacuum deposition at a deposition rate of 0.1 Å / sec and 0.9 Å / sec, respectively, thereby forming magnesium silver in a desired pattern ( (Thickness: 1 nm).
Furthermore, silver is formed in a desired pattern at a deposition rate of 1 mm / sec (thickness: 19 nm) for the purpose of emphasizing the interference effect and preventing voltage drop due to wiring resistance at the second electrode. )did.
A semitransparent electrode was formed by the above treatment.

Here, a microcavity effect (interference effect) appears between the first electrode and the second electrode, and the front luminance can be increased. Thereby, the light emission energy from an organic EL layer can be efficiently propagated to the light extraction part side. Similarly, the emission peak was adjusted to 460 nm and the half value width to 50 nm by the microcavity effect.

Next, an inorganic protective layer made of SiO _{2 having} a thickness of 3 μm was formed by patterning by plasma CVD using a shadow mask from the edge of the display portion to a sealing area of 2 mm in the vertical and horizontal directions.
By the above process, an organic EL element substrate on which an organic EL element was formed was obtained.

Next, the organic EL element substrate and the phosphor substrate produced as described above were aligned using an alignment marker formed outside the pixel arrangement position. A thermosetting resin was applied to the phosphor substrate in advance.
After aligning the organic EL element substrate and the phosphor substrate, the two substrates are brought into close contact with each other through a thermosetting resin, and heated at 80 ° C. for 2 hours to cure the thermosetting resin, and the organic EL element substrate and the phosphor The substrates were bonded together. Note that the step of bonding the two substrates was performed in a dry air environment (water content: −80 ° C.) in order to prevent the organic layer from being deteriorated by moisture.

Finally, an organic EL display device of Example 6 was completed by connecting terminals formed in the periphery to an external power source. Here, by applying a desired current to a desired striped electrode from an external power source, the blue light-emitting organic EL element is used as an excitation light source that can be arbitrarily switched, and blue light is converted into red light by a red phosphor layer. By converting blue light into green light in the green phosphor layer, red and green light emission can be obtained, and blue light emission can be obtained through the blue scatterer layer. It can be matched by the light distribution adjustment layer. As a result, full-color display was possible, and a good image and a display with good viewing angle characteristics that did not change in brightness or color even when viewed from any direction were obtained.

Further, using a commercially available luminance viewing angle measuring device (Ez-contrast: manufactured by ELDIM), in the organic EL display device of Example 6, chromaticity viewing angle characteristics when all 24 colors of Macbeth color are displayed are shown. It was measured. As a result, the chromaticity u'_60 °, v'_60 when the display device is viewed from the direction of the viewing angle of 60 ° relative to the value of the chromaticity u′_front, v′_front when the display device is viewed from the front. The color change Δu'v '(= √ ((u'_front-u'_60 °) ² + (v'_front-v'_60 °) ² )) is 0. 01 or less. In general, it is said that when the value of the color change Δu′v ′ is about 0.015 or less, a color difference cannot be detected by human eyes.

"Example 7" [active drive type blue organic EL + phosphor method]
A phosphor substrate was produced in the same manner as in Example 6.

An amorphous silicon semiconductor film was formed on a 100 × 100 mm square glass substrate by PECVD. Next, a polycrystalline silicon semiconductor film was formed by performing a crystallization treatment.
Next, the polycrystalline silicon semiconductor film was patterned into a plurality of islands using a photolithography method. Next, a gate insulating film and a gate electrode layer were formed in this order on the patterned polycrystalline silicon semiconductor layer, and patterning was performed using a photolithography method.

Thereafter, the patterned polycrystalline silicon semiconductor film was doped with an impurity element such as phosphorus to form source and drain regions, and a TFT element was fabricated. Thereafter, a planarizing film was formed. As the planarizing film, a silicon nitride film formed by PECVD and an acrylic resin layer formed by spin coater were laminated in this order.

Hereinafter, a method for forming the planarizing film will be described in detail.
First, after a silicon nitride film was formed, the silicon nitride film and the gate insulating film were collectively etched to form a contact hole leading to the source and / or drain region, and then a source wiring was formed.

Thereafter, an acrylic resin layer was formed, and a contact hole leading to the drain region was formed at the same position as the contact hole of the drain region drilled in the gate insulating film and the silicon nitride film, thereby completing the active matrix substrate. The function as a planarizing film is realized by an acrylic resin layer. Note that the capacitor for setting the gate potential of the TFT to a constant potential is formed by interposing an insulating film such as an interlayer insulating film between the drain of the switching TFT and the source of the driving TFT.

A driving TFT, a first electrode of a red light emitting organic EL element, a first electrode of a green light emitting organic EL element, and a first electrode of a blue light emitting organic EL element, penetrating a planarizing layer on an active matrix substrate Contact holes were formed to electrically connect the two.

Next, the first electrode (anode) of each pixel is formed by sputtering so as to be electrically connected to the contact hole provided through the planarization layer connected to the TFT for driving each light emitting pixel. Formed. The first electrode was formed by laminating an Al (aluminum) film having a thickness of 150 nm and an IZO (indium oxide-zinc oxide) film having a thickness of 20 nm.

Next, the first electrode was patterned into a shape corresponding to each pixel by a conventional photolithography method. Here, the area of the first electrode was 300 μm × 160 μm. Further, it was formed on a 100 × 100 square substrate. The display unit was 80 mm × 80 mm, a 2 mm wide sealing area was provided on the top, bottom, left, and right of the display unit, and a 2 mm terminal lead-out unit was further provided outside the sealing area on the short side of the display unit. On the long side of the display part, a 2 mm terminal extraction part was provided in the direction of bending.

Next, 200 nm of SiO ₂ was laminated on the first electrode by sputtering, and patterned to cover only the edge portion of the first electrode by conventional photolithography. Here, a structure in which four sides from the end of the first electrode by 10 μm are covered with SiO ₂ is used as an edge cover.

Next, the active matrix substrate on which the first electrode was formed was washed. As a method for cleaning the active matrix substrate, for example, acetone and isopropyl alcohol were used for ultrasonic cleaning for 10 minutes, followed by UV-ozone cleaning for 30 minutes.

Next, the active matrix substrate on which the first electrode is formed is fixed to a substrate holder in an in-line resistance heating vapor deposition apparatus, and the pressure is reduced to a vacuum of 1 × 10 ⁻⁴ Pa or less, and an organic EL layer including an organic light emitting layer is formed Each constituent layer was formed. Hereinafter, the formation method of each layer which comprises an organic EL layer is demonstrated in detail.
First, 1,1-bis-di-4-tolylamino-phenyl-cyclohexane (TAPC) was used as a hole injection material, and a hole injection layer having a thickness of 100 nm was formed by resistance heating vapor deposition.

Next, N, N′-di-1-naphthyl-N, N ′ ′-diphenyl-1,1′-biphenyl-1,1′-biphenyl-4,4′４-diamine (NPD) is used as a hole transport material. A hole transport layer having a thickness of 40 nm was formed by resistance heating vapor deposition. Next, a blue organic light emitting layer (thickness: 30 nm) was formed at a desired pixel position on the hole transport layer. This blue organic light-emitting layer comprises 1,4-bis-triphenylsilyl-benzene (UGH-2) (host material) and bis [(4,6-difluorophenyl) -pyridinato-N, C2 ′] picolinate iridium (III) (FIrpic) (blue phosphorescent dopant) was co-deposited at a deposition rate of 1.5 Å / sec and 0.2 Å / sec, respectively.

Thereafter, a semitransparent electrode was formed as the second electrode.
First, the active matrix substrate on which the organic EL layer was formed was fixed in a metal deposition chamber, and the shadow mask for forming the translucent electrode and the active matrix substrate were aligned. As the shadow mask, a mask provided with an opening so that the second electrode can be formed in a stripe shape having a width of 2 mm in a direction facing the stripe of the first electrode.

Next, an inorganic protective layer made of SiO _{2 having} a thickness of 3 μm was formed by patterning by plasma CVD using a shadow mask from the edge of the display portion to a sealing area of 2 mm in the vertical and horizontal directions.
Through the above process, an active drive type organic EL element substrate on which an organic EL element was formed was obtained.

Next, the active drive type organic EL element substrate and the phosphor substrate manufactured as described above were aligned using an alignment marker formed outside the pixel arrangement position. A thermosetting resin was applied to the phosphor substrate in advance.

After aligning the active drive type organic EL element substrate and the phosphor substrate, the two substrates are brought into close contact with each other through a thermosetting resin, and the thermosetting resin is cured by heating at 90 ° C. for 2 hours. And a phosphor substrate were bonded together. The step of bonding the two substrates was performed in a dry air environment (water content: −80 ° C.) in order to prevent the organic layer from being deteriorated by moisture.

Next, a polarizing plate was bonded to the substrate in the light extraction direction to obtain an active drive type organic EL element.

Finally, the terminal formed on the short side is connected to the power supply circuit via the source driver, and the terminal formed on the long side is connected to the external power supply via the gate driver, thereby 80 × An active drive organic EL display device having a display portion of 80 mm was completed.
Here, by applying a desired current to a desired striped electrode from an external power source, the blue light-emitting organic EL element is used as an excitation light source that can be arbitrarily switched, and blue light is converted into red light by a red phosphor layer. By converting blue light into green light in the green phosphor layer, red and green light emission can be obtained, and blue light emission can be obtained through the blue scatterer layer. It can be matched by the light distribution adjustment layer. Chromaticity shift As a result, full-color display is possible, and a good image and a display with good viewing angle characteristics with no change in brightness or color even when viewed from any direction were obtained.

Further, using a commercially available luminance viewing angle measuring device (Ez-contrast: manufactured by ELDIM), in the organic EL display device of Example 7, the chromaticity viewing angle characteristics when all 24 colors of Macbeth color are displayed respectively. It was measured. As a result, the chromaticity u'_60 °, v'_60 when the display device is viewed from the direction of the viewing angle of 60 ° relative to the value of the chromaticity u′_front, v′_front when the display device is viewed from the front. The color change Δu'v '(= √ ((u'_front-u'_60 °) ² + (v'_front-v'_60 °) ² )) is 0. 01 or less. In general, it is said that when the value of the color change Δu′v ′ is about 0.015 or less, a color difference cannot be detected by human eyes.

“Example 8” [Blue LED + phosphor method]
A phosphor substrate was produced in the same manner as in Example 6.

Using TMG (trimethylgallium) and NH ₃ , a buffer layer made of GaN was grown to a thickness of 60 nm on the C surface of the sapphire substrate set in the reaction vessel at 550 ° C. Next, the temperature was raised to 1050 ° C., and an n-type contact layer made of Si-doped n-type GaN was grown to a thickness of 5 μm using SiH ₄ gas in addition to TMG and NH ₃ . Next, TMA (trimethylaluminum) was added to the source gas, and a second cladding layer composed of a Si-doped n-type Al _0.3 Ga _0.7 N layer was grown at a thickness of 0.2 μm at 1050 ° C. .

Next, the temperature is lowered to 850 ° C., and the first n-type cladding layer made of Si-doped n-type In _0.01 Ga _0.99 N is made 60 nm using TMG, TMI (trimethylindium), NH ₃ and SiH _4. It was made to grow with the film thickness.

Next, an active layer made of non-doped In _0.05 Ga _0.95 N was grown to a thickness of 5 nm at 850 ° C. using TMG, TMI, and NH ₃ . Furthermore, in addition to TMG, TMI, and NH ₃ , a first p-type cladding layer made of Mg-doped p-type In _0.01 Ga _0.99 N at 850 ° C. using CPMg (cyclopentadienyl magnesium) newly. Was grown to a thickness of 60 nm.
Next, the temperature is raised to 1100 ° C., and a second p-type cladding layer made of Mg-doped p-type Al _0.3 Ga _0.7 N is grown to a thickness of 150 nm using TMG, TMA, NH ₃ , CPMg I let you.

Next, a p-type contact layer made of Mg-doped p-type GaN was grown to a thickness of 600 nm using TMG, NH ₃ and CPMg at 1100 ° C.
After the above operation was completed, the temperature was lowered to room temperature, the wafer was taken out of the reaction vessel, and the wafer was annealed at 720 ° C. to reduce the resistance of the p-type layer.

Next, a mask having a predetermined shape was formed on the surface of the uppermost p-type contact layer, and etching was performed until the surface of the n-type contact layer was exposed. After the etching, a negative electrode made of titanium (Ti) and aluminum (Al) was formed on the surface of the n-type contact layer, and a positive electrode made of nickel (Ni) and gold (Au) was formed on the surface of the p-type contact layer. After forming the positive electrode, after separating the wafer into 350 μm square chips, the LED chip is fixed with a UV curable resin on a substrate on which wiring for connecting to a separately prepared external circuit is formed. The wiring on the substrate was electrically connected to obtain a light source substrate made of a blue LED.

Next, the light source substrate and the phosphor substrate produced as described above were aligned with an alignment marker formed outside the pixel arrangement position. A thermosetting resin was applied to the phosphor substrate in advance.

After aligning the light source substrate and the phosphor substrate, the two substrates are brought into close contact with each other through the thermosetting resin, and heated at 80 ° C. for 2 hours to cure the thermosetting resin, and the organic EL element substrate and the phosphor substrate. Were pasted together. The step of bonding the two substrates was performed in a dry air environment (water content: −80 ° C.) in order to prevent the organic layer from being deteriorated by moisture.

Finally, the LED display device of Example 7 was completed by connecting the terminals formed in the periphery to an external power source.
Here, by applying a desired current to a desired striped electrode from an external power source, the blue light-emitting organic EL element is used as an excitation light source that can be arbitrarily switched, and blue light is converted into red light by a red phosphor layer. By converting blue light into green light in the green phosphor layer, red and green light emission can be obtained, and blue light emission can be obtained through the blue scatterer layer. It can be matched by the light distribution adjustment layer. As a result, full-color display was possible, and a good image and a display with good viewing angle characteristics that did not change in brightness or color even when viewed from any direction were obtained.

In addition, using a commercially available luminance viewing angle measurement device (Ez-contrast: manufactured by ELDIM), the display device of Example 8 measured chromaticity viewing angle characteristics when all 24 colors of Macbeth color were displayed. . As a result, the chromaticity u'_60 °, v'_60 when the display device is viewed from the direction of the viewing angle of 60 ° relative to the value of the chromaticity u′_front, v′_front when the display device is viewed from the front. The color change Δu'v '(= √ ((u'_front-u'_60 °) ² + (v'_front-v'_60 °) ² )) is 0. 01 or less. In general, it is said that when the value of the color change Δu′v ′ is about 0.015 or less, a color difference cannot be detected by human eyes.

"Example 9" [blue organic EL + liquid crystal + phosphor method]
A low refractive index layer having a thickness of 1 μm was formed on a glass substrate by spin coating. As a material for the low refractive index layer, “TPIR-414 T-3” manufactured by Tokyo Ohka Kogyo Co., Ltd. having a refractive index of about 1.2 to 1.3 was used. Next, a barrier (light scattering film) was formed on the low refractive index layer. Hereinafter, the method of forming the barrier will be described in detail. First, epoxy resin (refractive index: 1.59), acrylic resin (refractive index: 1.49), rutile-type titanium oxide (refractive index: 2.71, particle size 250 nm), photopolymerization initiator and aromatic A negative photosensitive resist was prepared by stirring and mixing a white photosensitive composition comprising a system solvent.

Next, a negative resist was applied on the glass substrate by a spin coater method. Then, it prebaked at 80 degreeC for 10 minute (s), and formed the coating film with a film thickness of 50 micrometers. After covering this coating film with a mask capable of forming a desired image pattern, the coating film was irradiated with i-line (300 mJ / cm ² ) and exposed.

Next, development was performed using an alkaline developer to obtain a pixel pattern structure having a barrier. Next, using a hot air circulation drying oven, post-baking was performed at 140 ° C. for 60 minutes to form a barrier partitioning the pixels.

To form a green phosphor layer, first, 100 g of a dichlorobenzene solution in which 10 wt% of polystyrene is dissolved is added to 0.01 g of coumarin, and then 40 g of hollow silica having a refractive index of 1.21 and a particle diameter of 20 nm is added. Then, the mixture was heated and stirred to produce a green phosphor forming coating solution.

Next, the prepared green phosphor forming coating solution was applied in a pattern to the area partitioned by the partition wall 103 by a dispenser method. Subsequently, it was dried by heating in a vacuum oven (200 ° C., 10 mmHg) for 4 hours, and a green phosphor layer was patterned with a film thickness of 5 μm.

In order to form a blue scatterer layer, first, as a binder for dispersing light scattering particles, a resin “LuxPrint 8155” manufactured by Teijin DuPont Co., Ltd .: 30 g, and Sekisui Plastics Co., Ltd. Polymer "SBX-4": 3.59 g and titanium oxide "R-25": 1.27 g manufactured by Sakai Chemical Industry Co., Ltd. with an average particle size of 200 nm are added and thoroughly mixed for 30 minutes in an automatic mortar. Using a dispersion stirrer “Filmix 40-40” manufactured by Co., Ltd., pre-stirring was performed for 15 minutes at an agitating speed of 6,000 rpm under an open system room temperature to obtain a coating solution for forming a blue light scattering layer. .
Next, the produced blue light scattering layer forming coating solution was applied in a pattern to a region partitioned by the partition wall by a dispenser technique. Subsequently, it was dried by heating in a vacuum oven (200 ° C., 10 mmHg) for 4 hours to form a blue firefly scatterer layer with a film thickness of 5 μm.

Next, a low refractive index layer having a thickness of 1 μm was formed on the entire surface of the red phosphor layer, the green phosphor layer, and the blue scatterer layer on the side on which the excitation light is incident by spin coating. As a material for the low refractive index layer, “TPIR-414 T-3” manufactured by Tokyo Ohka Kogyo Co., Ltd. having a refractive index of about 1.2 to 1.3 was used.

Next, a 5 μm thick light distribution adjusting layer was formed on one surface of the glass substrate using a commercially available spin coater.

Next, a flattening film is formed on the wavelength selective transmission / reflection layer by spin coating using an acrylic resin, and a polarizing film, a transparent electrode, and a light distribution film are formed on the flattening film by a conventional method. A glass substrate, a phosphor layer formed on one surface thereof, a light distribution adjusting layer formed on the opposite surface, a barrier formed on a side surface of the phosphor layer, and excitation of the phosphor layer A phosphor substrate of Example 9 comprising a wavelength selective transmission / reflection layer formed on one surface of the light incident surface side was obtained.

Next, a switching element made of TFT was formed on the glass substrate by a conventional method. Next, an ITO transparent electrode having a film thickness of 100 nm was formed so as to be in electrical contact with the TFT through the contact hole.

Next, the transparent electrode was patterned by a normal photolithography method so as to have the same pitch as the pixels of the organic EL portion that had been prepared in advance.
Next, an alignment film was formed by a printing method.

Next, the substrate on which the TFT is formed and the phosphor substrate are bonded via a spacer having a thickness of 10 μm, and a TN mode liquid crystal material is injected between both substrates to complete the liquid crystal / phosphor portion. .

On the other hand, a reflective electrode having a thickness of 100 nm made of silver is formed on a glass substrate having a thickness of 0.7 mm by a sputtering method, and a 20 nm-thick indium-tin oxide film is formed on the reflective electrode by a sputtering method. A first electrode (anode) was formed by depositing an object (ITO).
Then, it patterned so that the width | variety of a 1st electrode might become a desired magnitude | size by the conventional photolithographic method.

Next, the substrate on which the first electrode is formed is fixed to a substrate holder in an in-line type resistance heating vapor deposition apparatus, and the pressure is reduced to a vacuum of 1 × 10 ⁻⁴ Pa or less to form an organic EL layer including an organic light emitting layer. Each layer was formed. Hereinafter, the formation method of each layer which comprises an organic EL layer is demonstrated in detail. First, 1,1-bis-di-4-tolylamino-phenyl-cyclohexane (TAPC) was used as a hole injection material, and a hole injection layer having a thickness of 100 nm was formed by resistance heating vapor deposition.

Next, carbazole biphenyl (CBP) was used as a hole transport material, and a 10 nm-thick hole transport layer was formed by resistance heating vapor deposition. Next, a near ultraviolet organic light emitting layer (thickness: 30 nm) was formed at a desired pixel position on the hole transport layer. This near-ultraviolet organic light-emitting layer is formed by depositing 3,5-bis (4-tert-butyl-phenyl) -4-phenyl- [1,2,4] triazole (TAZ) (near-ultraviolet phosphorescent material) at a deposition rate of 1 It was formed by vapor deposition at a rate of 5 cm / sec.

Next, a hole blocking layer (thickness: 20 nm) was formed on the organic light emitting layer using 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline (BCP). Next, an electron transport layer (thickness: 30 nm) was formed on the hole blocking layer using tris (8-hydroxyquinoline) aluminum (Alq ₃ ).
Next, an electron injection layer (thickness: 0.5 nm) was formed on the electron transport layer using lithium fluoride (LiF).
Through the above processing, each layer constituting the organic EL layer was formed.

Thereafter, a semitransparent electrode was formed as the second electrode.
First, the substrate was fixed to a metal deposition chamber, and the shadow mask for forming the translucent electrode was aligned with the substrate. As the shadow mask, a mask provided with an opening so that the second electrode can be formed in a stripe shape having a width of 500 μm and a pitch of 600 μm in a direction facing the stripe of the first electrode.

A microcavity effect (interference effect) appears between the first electrode and the second electrode, and the front luminance can be increased. Thereby, the light emission energy from an organic EL layer can be efficiently propagated to the light extraction part side. Similarly, the emission peak was adjusted to 370 nm and the half-value width to 30 nm by the microcavity effect.

The organic EL element substrate and the phosphor substrate produced as described above were aligned using an alignment marker formed outside the pixel arrangement position. A thermosetting resin was applied to the phosphor substrate in advance.

After aligning the organic EL element substrate and the phosphor substrate, the two substrates are brought into close contact with each other through a thermosetting resin, and heated at 80 ° C. for 2 hours to cure the thermosetting resin, and the organic EL element substrate and the phosphor The substrates were bonded together. The step of bonding the two substrates was performed in a dry air environment (water content: −80 ° C.) in order to prevent the organic layer from being deteriorated by moisture.

Finally, an organic EL display device of Example 8 was completed by connecting terminals formed in the periphery to an external power source.
Here, by applying a desired current to a desired striped electrode from an external power source, the blue light-emitting organic EL element is used as an excitation light source that can be arbitrarily switched, and blue light is converted into red light by a red phosphor layer. By converting blue light into green light in the green phosphor layer, red and green light emission can be obtained, and blue light emission can be obtained through the blue scatterer layer. It can be matched by the light distribution adjustment layer. As a result, full-color display was possible, and a good image and a display with good viewing angle characteristics that did not change in brightness or color even when viewed from any direction were obtained.

In addition, using a commercially available luminance viewing angle measurement device (Ez-contrast: manufactured by ELDIM), the display device of Example 9 measured chromaticity viewing angle characteristics when all 24 colors of Macbeth color were displayed. . As a result, the chromaticity u′_60 °, v′_60 when the device is viewed from the direction of the viewing angle of 60 ° with respect to the values of the chromaticity u′_front and v′_front when the display device is viewed from the front. The color change Δu′v ′ (= √ ((u′_front−u′_60 °) 2+ (v′_front−v′_60 °) ² ))) is 0.01 for all 24 colors. It was the following. Generally, it is said that the color difference cannot be detected by human eyes when the value of the color change Δu′v ′ is about 0.015 or less.

“Example 10” [blue backlight + liquid crystal + phosphor method]
In the same manner as in Example 9, a liquid crystal / phosphor substrate portion was formed.

Next, a directional blue backlight was combined on the liquid crystal side of the liquid crystal / phosphor substrate.

As the directional blue backlight, a light source, a light guide plate, a reflection sheet, a brightness enhancement film, and a condensing lens were used. As a light source, an LED “NFSC036C” manufactured by Nichia Corporation having a peak wavelength of 465 nm was used and arranged on the side surface of the light guide plate. As the light guide plate, a polycarbonate resin formed into a wedge shape by injection molding was used. A reflective sheet “ESR” manufactured by 3M was used for the bottom surface of the light guide plate (the LED was provided on the side of the wedge-shaped light guide plate having the larger cross-sectional area). The brightness enhancement film “DBEFD400” manufactured by 3M Co., Ltd. and the condensing Fresnel lens “CF3-0.1” manufactured by Nippon Special Optical Resin Co., Ltd. are mounted in this order on the upper surface side (outgoing surface side) of the light guide plate. Completed the backlight.

Finally, the terminal formed in the periphery was connected to an external power source to complete the liquid crystal display device of Example 10. Here, by applying a desired current to a desired stripe-shaped electrode from an external power source, the emitted light from the directional blue backlight is used as an excitation light source that can be arbitrarily switched, and blue light is converted into red by a red phosphor film. By converting blue light into green light with the green phosphor film, isotropic light emission of red and green is obtained, and isotropic blue light emission is achieved through the blue scatterer film. Obtained. Furthermore, the light distribution adjustment layer provided on the phosphor layer and the scatterer layer provides a display that does not change in brightness when viewed from any direction and does not change color when viewed from any direction. It was. Thereby, full color display was possible, and a good image and an image with good viewing angle characteristics could be obtained.

The present invention can be used for a phosphor substrate, various light emitting devices using the phosphor substrate, a display device, and a lighting device.

Claims

A substrate on which a phosphor layer that is excited by excitation light and emits fluorescence is formed on one side, and a light distribution adjustment layer that changes at least the emission direction of fluorescence emitted from the phosphor layer is formed. Phosphor substrate.
2. The phosphor substrate according to claim 1, wherein the light distribution adjusting layer is made of a light scattering material containing a translucent resin in which at least one particle is mixed.
A light emitting device comprising the phosphor substrate according to claim 1 and an excitation light source that emits the excitation light.
The light-emitting device according to claim 3, wherein the light distribution adjustment layer is disposed between the substrate and the phosphor layer.
The light distribution adjusting layer has a luminance value L1 in a direction of a viewing angle of 0 ° that is a normal direction perpendicular to the emitting surface and a viewing angle of 0 ° from the emitting surface facing the incident surface of the excitation light on the substrate. 5. The light emitting device according to claim 3, wherein fluorescence is emitted so that a relationship with a luminance value L <b> 2 having a larger viewing angle satisfies at least L <b> 1 ≧ L <b> 2.
The light-emitting device according to claim 5, wherein the light distribution adjusting layer emits fluorescence so that a relationship between the luminance value L1 and the luminance value L2 satisfies L2 / L1 ≧ 0.8.
The light distribution adjustment layer emits fluorescence so that the relationship between the luminance value L1 and the luminance value L3 in the direction of the viewing angle of 60 ° satisfies at least L3 / L1 ≧ 0.8. Item 7. The light emitting device according to Item 6.
The light emitting device according to any one of claims 3 to 7, wherein a light reflective barrier is formed on at least one side surface along the thickness direction of the phosphor layer.
The excitation light incident surface side of the phosphor layer transmits at least excitation light in a peak wavelength region of the excitation light wavelength range, and peaks in the fluorescence wavelength range emitted from the phosphor layer. The light emitting device according to any one of claims 3 to 8, wherein a wavelength selection layer that reflects at least fluorescence in a wavelength region is formed.
The light emitting device according to claim 9, wherein a low refractive index layer having a refractive index smaller than that of the phosphor layer is disposed between the phosphor layer and the wavelength selection layer.
The light-emitting device according to claim 10, wherein the low refractive index layer is further disposed between the light distribution adjusting layer and the phosphor layer.
The light emitting device according to claim 10 or 11, wherein the refractive index of the low refractive index layer is in the range of 1 to 1.5.
The light-emitting device according to claim 12, wherein the low refractive index layer is made of a gas.
14. The light emitting device according to claim 3, wherein a plurality of the phosphor layers are arranged side by side on one surface of the substrate.
The light emitting device according to claim 14, wherein a plurality of the light distribution adjustment layers are arranged side by side so as to correspond to each of the plurality of phosphor layers.
16. The light emitting device according to claim 14 or 15, wherein a light absorption layer is further disposed between the phosphor layers adjacent to each other.
The light-emitting device according to claim 16, wherein the light absorption layer is further disposed between the light distribution adjustment layers adjacent to each other.
The light-emitting device according to any one of claims 14 to 17, wherein the light absorption layer is formed on at least one of an upper surface and a lower surface extending perpendicularly to a thickness direction of the barrier.
The light-emitting device according to claim 14, wherein at least a portion of the barrier that is in contact with the phosphor layer has light scattering properties.
The light-emitting device according to any one of claims 14 to 19, wherein at least a portion of the barrier in contact with the phosphor layer has an uneven shape.
21. The light-emitting device according to claim 14, wherein the light distribution adjustment layer extends along an emission surface of the substrate that faces the incident surface of the excitation light.
A display device comprising the light-emitting device according to any one of claims 3 to 21.
The excitation light source emits excitation light in the ultraviolet wavelength region,
The phosphor layer comprises a red phosphor layer that constitutes a red pixel that emits red light by excitation light in the ultraviolet wavelength region, and a green phosphor layer that constitutes a green pixel that emits green light by excitation light in the ultraviolet wavelength region 23. The display device according to claim 22, further comprising at least a blue phosphor layer that forms a blue pixel that emits blue light by excitation light in the ultraviolet wavelength region.
The excitation light source emits excitation light in a blue wavelength region,
The phosphor layer includes a red phosphor layer that constitutes a red pixel that emits red light by the excitation light in the blue wavelength region, and a green phosphor layer that constitutes a green pixel that emits green light by the excitation light in the blue wavelength region. The display device according to claim 22, further comprising: a blue scatterer layer that constitutes a blue pixel that scatters excitation light in the blue wavelength region.
25. The display device according to claim 24, wherein the blue scatterer layer and the light distribution adjustment layer are integrally formed.
The excitation light source emits excitation light in a blue wavelength region,
The phosphor layer includes a red phosphor layer that constitutes a red pixel that emits red light by the excitation light in the blue wavelength region, and a green phosphor layer that constitutes a green pixel that emits green light by the excitation light in the blue wavelength region. 23. The display device according to claim 22, further comprising at least a blue phosphor layer that constitutes a blue pixel that emits blue light by excitation light in the blue wavelength region.
27. The display device according to claim 22, wherein an active matrix driving element corresponding to the excitation light source is disposed.
The display device according to any one of claims 22 to 27, wherein the excitation light source includes any one of a light emitting diode, an organic electroluminescence element, and an inorganic electroluminescence element.
29. The liquid crystal device according to claim 22, wherein the excitation light source is a planar light source, and a liquid crystal element capable of controlling the transmittance of the excitation light is formed between the excitation light source and the substrate. Item 1. A display device according to item 1.
The display device according to any one of claims 22 to 29, wherein the excitation light emitted from the excitation light source has directivity.
31. The display device according to claim 22, wherein a polarizing plate having an extinction ratio of 10,000 or more at a wavelength of 435 nm or more and 480 nm or less is provided between the excitation light source and the substrate.
32. A color filter is provided between at least one of the phosphor layer and the light distribution adjustment layer, or at least one of the light distribution adjustment layer and the substrate. The display device described in 1.
The color change Δu′v ′ of the omnidirectional chromaticity u ′, v ′ with respect to the value of the chromaticity u ′, v ′ in the front direction of the light emitted from the light emitting surface is 0.01 or less. The display device according to any one of claims 22 to 32.
34. The display device according to any one of claims 22 to 33, wherein an external light antireflection layer for preventing reflection of external light is provided on the light distribution adjustment layer or the substrate.
The display device according to claim 34, wherein the refractive index of the external light antireflection layer has a refractive index gradient that gradually increases or decreases along the thickness direction.
A lighting device comprising the light-emitting device according to any one of claims 3 to 21.