WO2010073585A1 - シート及び発光装置 - Google Patents
シート及び発光装置 Download PDFInfo
- Publication number
- WO2010073585A1 WO2010073585A1 PCT/JP2009/007063 JP2009007063W WO2010073585A1 WO 2010073585 A1 WO2010073585 A1 WO 2010073585A1 JP 2009007063 W JP2009007063 W JP 2009007063W WO 2010073585 A1 WO2010073585 A1 WO 2010073585A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- light
- microregions
- minute
- regions
- portions
- Prior art date
Links
Images
Classifications
-
- H—ELECTRICITY
- H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
- H10K—ORGANIC ELECTRIC SOLID-STATE DEVICES
- H10K50/00—Organic light-emitting devices
- H10K50/80—Constructional details
- H10K50/85—Arrangements for extracting light from the devices
-
- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B5/00—Optical elements other than lenses
- G02B5/30—Polarising elements
- G02B5/3025—Polarisers, i.e. arrangements capable of producing a definite output polarisation state from an unpolarised input state
-
- G—PHYSICS
- G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
- G09F—DISPLAYING; ADVERTISING; SIGNS; LABELS OR NAME-PLATES; SEALS
- G09F13/00—Illuminated signs; Luminous advertising
- G09F13/20—Illuminated signs; Luminous advertising with luminescent surfaces or parts
- G09F13/22—Illuminated signs; Luminous advertising with luminescent surfaces or parts electroluminescent
Definitions
- the present invention relates to a transparent sheet used with one surface being adjacent to a light emitter, and a light emitting device using the same.
- FIG. 18 is a diagram showing a cross-sectional configuration of a light-emitting device using a general organic electroluminescence element (organic EL element) and a state of light propagation.
- organic EL element an electrode 102, a light emitting layer 103, and a transparent electrode 104 are laminated in this order on a substrate 101, and a transparent substrate 105 is provided on the transparent electrode 104.
- a voltage is applied between the electrode 102 and the transparent electrode 104, light emission occurs at a point S inside the light emitting layer 103.
- This light is reflected directly or after being reflected at the electrode 102, then passes through the transparent electrode 104, enters the point P on the surface of the transparent substrate 105 at an angle ⁇ with respect to the surface normal to the surface, and is refracted at this point. Then, the light is emitted to the air layer 106 side.
- FIGS. 19A and 19B are explanatory views for explaining light extraction efficiency when it is assumed that the transparent substrate 105 has a multilayer structure in the light emitting device.
- the refractive index of the light emitting layer 103 is n ′ k
- the refractive index of the air layer 106 is n 0
- the refractive indexes of a plurality of transparent layers interposed between the light emitting layer 103 and the air layer 106 are the light emitting layers.
- FIG. 19B schematically shows the range of light that can be extracted from the light emitting layer 103.
- the light that can be extracted is located in two pairs of cones 107 and 107 ′ with the light emitting point S as the apex, the apex angle as twice the critical angle ⁇ c , and the z axis along the surface normal of the refractive surface as the central axis. included.
- the extraction efficiency ⁇ from the light emitting layer 103 is It is equal to the ratio of the area obtained by cutting the spherical surface 108 by the cones 107 and 107 ′ to the surface area of the spherical surface 108, and is given by the following (Equation 3).
- the transmittance does not reach 100% even at an incident angle within the critical angle, so the actual extraction efficiency ⁇ is smaller than 1-cos ⁇ c .
- the total efficiency of the light emitting element is a value obtained by multiplying the light emission efficiency of the light emitting layer by the extraction efficiency ⁇ .
- Patent Document 1 in an organic EL element, a diffraction grating is formed on a substrate interface or a reflecting surface for the purpose of suppressing total reflection on the surface of the transparent substrate when light is emitted from the transparent substrate to the atmosphere. It is disclosed that light extraction efficiency is improved by changing the incident angle of light with respect to the extraction surface.
- Patent Document 2 in order to provide a planar light emitting device with high light extraction efficiency, a plurality of transparent protrusions are formed on the surface of the transparent substrate in the organic EL element, and light at the interface between the transparent substrate and air is formed. It is described that reflection can be prevented.
- the conventional light emitting device as described above has the following problems.
- the light extraction efficiency ⁇ from the light-emitting layer 103 does not exceed 1-cos ⁇ c at the maximum, and the light extraction is performed once the refractive index of the light-emitting layer 103 is determined.
- the technique disclosed in Patent Document 1 it is possible to extract the light that should be totally reflected, but the opposite is also true. That is, when there is no diffraction grating layer, light that is transmitted and refracted by being incident on the refracting surface (outgoing surface) of the transparent substrate at an angle smaller than the critical angle is diffracted by the diffraction grating layer, so May exceed the critical angle and cause total reflection. Therefore, the technique disclosed in Patent Document 1 does not guarantee improvement in light extraction efficiency. Furthermore, the technique disclosed in Patent Document 1 generates diffracted light in which all light rays are uniformly bent by a predetermined angle. The light including such diffracted light has a distribution of light intensity depending on the direction, and the angle at which the light is bent depends on the wavelength of the emitted light, so that there is a color imbalance depending on the direction.
- the light emitting device disclosed in Patent Document 2 is for the purpose of preventing reflection of light on the refracting surface, and the improvement of the light extraction efficiency by this structure is as small as about 20%.
- the present invention has been made in view of such a point, and its purpose is to emit light incident on a transparent substrate having a critical angle or more to realize a significant improvement in light extraction efficiency and prevent reflection, It is an object of the present invention to provide a sheet and a light emitting device that suppress the occurrence of light intensity distribution and color imbalance due to orientation.
- the first sheet of the present invention is a sheet used so that light from a light emitter is incident on one surface and exits from the other surface, and the diameter of the largest circle inscribed in the other surface Includes a plurality of micro regions ⁇ having a size of 0.2 ⁇ m or more and 2 ⁇ m or less, and each of the micro regions ⁇ is adjacent to another micro region ⁇ of the plurality of micro regions ⁇ .
- the plurality of microregions ⁇ include a plurality of microregions ⁇ 1 randomly selected from the plurality of microregions ⁇ at a ratio of 20% to 80% and a plurality of other microregions ⁇ 2.
- the phase difference between the light transmitted through the plurality of micro regions ⁇ 1 and the light transmitted through the plurality of micro regions ⁇ 2 is ⁇ .
- a half-wave plate having an aligned optical axis is disposed in each of the plurality of minute portions d1 and the plurality of minute portions d2, and the light of the half-wave plate of the plurality of minute portions d1.
- the axial direction and the optical axis direction of the half-wave plate of the plurality of minute portions d2 are arranged at an angle of 45 degrees.
- the second sheet of the present invention is a sheet used so that light from the light emitter enters one surface and exits from the other surface, and the diameter of the largest circle inscribed in the other surface Includes a plurality of micro regions ⁇ having a size of 0.2 ⁇ m or more and 2 ⁇ m or less, and each of the micro regions ⁇ is adjacent to another micro region ⁇ of the plurality of micro regions ⁇ .
- the plurality of microregions ⁇ include a plurality of microregions ⁇ 1 randomly selected from the plurality of microregions ⁇ at a ratio of 20% to 80% and a plurality of other microregions ⁇ 2.
- a polarizer having a uniform transmission axis is disposed in each of the plurality of minute portions d2, and the polarization axes constituting the plurality of minute portions d2 and the transmission axes of the polarizers disposed in the plurality of minute portions d1. It is orthogonal to the transmission axis of the child.
- the third sheet of the present invention is a sheet used so that light from the light emitter is incident on one surface and is emitted from the other surface, and the diameter of the largest circle inscribed in the other surface Includes a plurality of micro regions ⁇ having a size of 0.2 ⁇ m or more and 2 ⁇ m or less, and each of the micro regions ⁇ is adjacent to another micro region ⁇ of the plurality of micro regions ⁇ .
- the plurality of microregions ⁇ include a plurality of microregions ⁇ 1 randomly selected from the plurality of microregions ⁇ at a ratio of 20% to 80% and a plurality of other microregions ⁇ 2.
- the plurality of minute regions ⁇ 1 and the plurality of minute regions ⁇ 2 are polygonal, and the plurality of minute regions ⁇ 1 and the plurality of minute regions ⁇ 2 are congruent to each other.
- a first light-emitting device of the present invention is a light-emitting device including a light-emitting body and a protective layer provided on a light-emitting surface of the light-emitting body, the light-emitting surface side being opposite to the light-emitting surface side in the protective layer.
- the surface is provided with a plurality of minute regions ⁇ having a maximum inscribed circle diameter of 0.2 ⁇ m or more and 2 ⁇ m or less, and each of the plurality of minute regions ⁇ includes one of the plurality of minute regions ⁇ .
- the plurality of minute regions ⁇ are adjacent and surrounded by a plurality of minute regions ⁇ , and the plurality of minute regions ⁇ are randomly selected at a rate of 20% to 80% from the plurality of minute regions ⁇ .
- the phase difference between the light transmitted through the plurality of microregions ⁇ 1 and the light transmitted through the plurality of microregions ⁇ 2 is ⁇ ,
- the surface opposite to the light emitting layer side is the refractive index of the protective layer. It is in contact with a medium having a lower refractive index.
- a half-wave plate having an aligned optical axis is disposed in each of the plurality of minute portions d1 and the plurality of minute portions d2, and the light of the half-wave plate of the plurality of minute portions d1.
- the axial direction and the optical axis direction of the half-wave plate of the plurality of minute portions d2 are arranged at an angle of 45 degrees.
- a second light-emitting device of the present invention is a light-emitting device including a light-emitting body and a protective layer provided on a light-emitting surface of the light-emitting body, wherein the protective layer is opposite to the light-emitting surface side.
- the surface is provided with a plurality of minute regions ⁇ having a maximum inscribed circle diameter of 0.2 ⁇ m or more and 2 ⁇ m or less, and each of the plurality of minute regions ⁇ includes one of the plurality of minute regions ⁇ .
- the plurality of minute regions ⁇ are adjacent and surrounded by a plurality of minute regions ⁇ , and the plurality of minute regions ⁇ are randomly selected at a rate of 20% to 80% from the plurality of minute regions ⁇ .
- a surface of the protective layer on the side opposite to the light emitting layer side is in contact with a medium having a refractive index lower than the refractive index of the protective layer.
- a plurality of minute portions d2 including each of the plurality of minute regions ⁇ 2 and extending in the thickness direction, and each of the plurality of minute portions d1 and the plurality of minute portions d2 includes: Polarizers with uniform transmission axes are arranged, and the transmission axes of the polarizers arranged in the plurality of minute portions d1 are orthogonal to the transmission axes of the polarizers constituting the plurality of minute portions d2.
- a third light-emitting device of the present invention is a light-emitting device including a light-emitting body and a protective layer provided on a light-emitting surface of the light-emitting body, the light-emitting surface side being opposite to the light-emitting surface side in the protective layer.
- the surface is provided with a plurality of minute regions ⁇ having a maximum inscribed circle diameter of 0.2 ⁇ m or more and 2 ⁇ m or less, and each of the plurality of minute regions ⁇ includes one of the plurality of minute regions ⁇ .
- the plurality of minute regions ⁇ are adjacent and surrounded by a plurality of minute regions ⁇ , and the plurality of minute regions ⁇ are randomly selected at a rate of 20% to 80% from the plurality of minute regions ⁇ .
- a surface of the protective layer on the side opposite to the light emitting layer side is in contact with a medium having a refractive index lower than the refractive index of the protective layer.
- a plurality of minute regions ⁇ 1 extending in the thickness direction.
- a plurality of minute portions d2 including each of the plurality of minute regions ⁇ 2 and extending in the thickness direction, and any one of the plurality of minute portions d1 and the plurality of minute portions d2 On one side, a light shielding surface is provided.
- the medium is air.
- the medium is an airgel.
- the diameter of the largest circle inscribed in the minute regions ⁇ 1 and ⁇ 2 is in the range of 0.2 ⁇ m or more and 2 ⁇ m or less, and the direction and the magnitude of the electric field vector for light transmitted through the minute regions ⁇ 1 and ⁇ 2.
- the phase is discontinuous at the boundary between the minute regions ⁇ 1 and ⁇ 2.
- the circular integration of the electric field vector or magnetic field vector of the light incident on the refracting surface is not zero, so that light is generated at the boundary between the minute regions ⁇ 1 and ⁇ 2 (boundary diffraction effect).
- This phenomenon makes it possible to extract light incident on the minute regions ⁇ 1 and ⁇ 2 at an angle exceeding the critical angle.
- the light reflected on the ground before entering the minute regions ⁇ 1 and ⁇ 2 is also reflected again on the sheet side on the ground and again enters the minute regions ⁇ 1 and ⁇ 2.
- the light extraction efficiency can be greatly improved.
- (A) is a figure which shows progress of the light 106 in the refractive surface 107a vicinity
- (b) is a figure which shows the step-like change of the refractive index in the refractive surface 107a vicinity
- (c) is a refractive index vicinity. It is a figure which shows the gentle change of the refractive index in 107a vicinity
- (d) is a graph which shows the relationship between the incident angle and the transmittance
- (A) is a figure which shows the cross section of the light-emitting device provided with the diffraction grating which has a periodic structure on the surface
- (b) is a figure which shows the upper surface of the light-emitting device shown to (a).
- (A) is a figure which shows the cross section of the light-emitting device provided with the 1986
- (b) is a figure which shows the upper surface of the light-emitting device shown to (a).
- (A)-(h) is a figure for demonstrating the boundary condition of the field of the light in a refracting surface.
- (A) is a diagram in which pinholes are arranged, and (b) is a diagram in which phase shifters are arranged.
- (A) is a graph showing the incident angle dependence of the transmittance t on the refractive surface in the structure shown in FIG.
- FIG. 6 shows the reason why the amount of light emitted from the structure shown in FIG. 6 increases. It is a figure for demonstrating. It is a figure which shows the mode of the cross-sectional structure of the organic electroluminescent element of 1st Embodiment by this invention, and the propagation of light. (A) is a figure which expands and shows a part of fine field 13 in a 1st embodiment, and (b) is a pattern figure in a wider range than (a). It is a figure which shows the pattern of the protective layer of 1st Embodiment.
- (A) is a figure which shows the 1st pattern of 4th Embodiment
- (b) is a figure which shows a 2nd pattern.
- (A) is a figure which shows the mode of the cross-sectional structure of the organic electroluminescent element of other embodiment, and the propagation of light. It is a figure which shows the mode of the cross-sectional structure of the organic electroluminescent element which is a prior art example, and the propagation state of light.
- (A) is a transparent substrate of a multilayer structure
- (b) is a figure for demonstrating the range of the light which can be taken out.
- 1 (a) to 1 (d) are diagrams for explaining the transmittance on the refracting surface (interface between the transparent layer surface and the air layer).
- the light 108 shown in FIG. 1A enters the refractive surface 107a of the transparent layer 107 from the inside of the transparent layer 107 having a refractive index of 1.5 along the paper surface direction at an angle ⁇ , and enters the air side (refractive index of 1.0). ). In the refracting surface 107a, the light 108 is refracted in a direction approaching the refracting surface 107a.
- FIGS. 1B and 1C show the refractive index distribution in the vicinity of the refractive surface 107a.
- the vertical axis indicates the transparent layer 107 and the position in the air.
- the position where the value of the vertical axis is 0 is the refractive surface 107a.
- the horizontal axis in FIGS. 1B and 1C indicates the refractive index.
- the refractive index distribution along the surface normal near the refractive surface 107a is stepped as shown in FIG. 1B, and the refractive index changes discontinuously with the refractive surface 107a as a boundary.
- the P-polarized light (vibration component whose electric field vector is parallel to the paper surface) has transmittance characteristics as shown by the curve 108a in FIG. 1D
- the S-polarized light (vibration component whose electric field vector is orthogonal to the paper surface) has transmittance characteristics as shown by the curve 108b.
- the P-polarized light has a curve 108A in FIG. S-polarized light exhibits transmittance characteristics as shown by curve 108B. Similar to the curves 108a and 108b, the transmittance of the curves 108A and 108B becomes zero when the critical angle is exceeded. On the other hand, the transmittance below the critical angle is closer to 100% in the curve 108A than in the curve 108a. Similarly, the transmittance below the critical angle is closer to 100% in the curve 108B than in the curve 108b.
- the multilayer structure in FIG. 1 (c) has a structure in which 50 layers of 0.01 ⁇ m thick films having a refractive index of 1.5 to 1.0 with a deviation of 0.01 are stacked. As the rate change gradient becomes gentler, the difference between the P-polarized light and the S-polarized light disappears, and in both cases, the result of the graph of the transmittance with respect to the incident angle approaches the step function is obtained.
- the light emitting device shown in FIGS. 2A and 2B is an organic EL element in which a diffraction grating 209 is provided at the interface between the transparent substrate 205 and the transparent electrode 204.
- an electrode 202, a light emitting layer 203, a transparent electrode 204, and a diffraction grating layer 209 are stacked in this order on a substrate 201, and a transparent substrate 205 is provided on the diffraction grating layer 209.
- the diffraction grating layer 209 has an uneven periodic structure with a pitch ⁇ in the x direction and the y direction on the surface in contact with the transparent substrate 205.
- the shape of the convex portions is a square having a width w as shown in FIG. 2B, and the convex portions are arranged in a staggered pattern.
- the electrode 202 and the transparent electrode 204 By applying a voltage between the electrode 202 and the transparent electrode 204, light is emitted from the inside of the light emitting layer 203 (for example, the point S). This light is reflected directly or after being reflected by the electrode 202, then passes through the transparent electrode 204, passes through the diffraction grating layer 209, and is diffracted. For example, assuming that the light 210a emitted from the point S travels straight without being diffracted in the diffraction grating layer 209, the light 210a is incident on the refractive surface 205a of the transparent substrate 205 at an angle greater than the critical angle and totally reflected as in the light 210b. Actually, since the diffraction grating layer 209 diffracts, the incident angle with respect to the refractive surface 205a becomes smaller than the critical angle like the light 210c. In this way, total reflection of light can be prevented.
- FIG. 3 shows a circle 211 having a radius n A and a circle 212 having a radius n B centered on the point O.
- An orthogonal vector (vector from the perpendicular foot A to the point O) onto the refracting surface 207a of the incident vector 210i (a vector starting from the circumference of the circle 211 toward the point O at an angle ⁇ ) is 210I
- the point O is A vector 210r having an end point on the circumference of the circle 212 as a start point is drawn so that the orthogonal projection vector 210R is the same as the vector 210I.
- q is a diffraction order (integer).
- the distance in the x direction (the length of the vector 210I) that the light 210i travels through the transparent layer 207 (refractive index n A ) per unit time is represented by n A ⁇ sin ⁇ .
- the distance in the x direction (the length of the vector 210R) that the light 210r travels through the transparent layer 206 (refractive index n B ) per unit time is represented by n B ⁇ sin ⁇ .
- Equation 4 gives the azimuth angle ⁇ (angle formed with the refracting surface normal) of the vector 210r that gives the direction of the refracted light beam. This is Snell's law itself.
- the azimuth angle ⁇ ′ (angle formed with the refracting surface normal) of the vector 210d that gives the azimuth of the diffracted ray is given by However, since the angle ⁇ ′ in FIG. 3 straddles the z-axis (refractive surface normal passing through the point O), it is defined as minus.
- the direction in which the diffracted light beam (vector 210d) travels is shifted by q ⁇ / ⁇ from the direction in which the refracted light beam (vector 210r) travels.
- the light ray 210b assumed not to be diffracted corresponds to the refracted light ray (vector 210r) in FIG.
- the light beam 210c diffracted in FIG. 2 corresponds to the diffracted light beam (vector 210d) in FIG.
- the light ray 210c is displaced from the light ray 210b by the amount of q ⁇ / ⁇ , so that it avoids total reflection at the refractive surface 205a. In this way, since the light to be totally reflected can be extracted, it is considered that the light extraction efficiency can be improved as compared with the organic EL light emitting device having no diffraction grating layer.
- the following problems become apparent. Assuming that the light 210A goes straight without being diffracted in the diffraction grating layer 209, it enters the refracting surface 205a of the transparent substrate 205 at an angle less than the critical angle and refracts and transmits the refracting surface 205a like the light 210B. However, since the diffraction grating layer 209 actually diffracts, the incident angle with respect to the refracting surface 205a becomes larger than the critical angle and totally reflects like the light 210C. Therefore, even if such a diffraction grating layer 209 is provided, improvement in light extraction efficiency is not necessarily guaranteed.
- diffracted light whose azimuth is uniformly shifted by q ⁇ / ⁇ is generated with respect to all light rays.
- the light intensity is distributed depending on the azimuth, and the shift width q ⁇ / ⁇ depends on the wavelength ⁇ of the emitted light, so that there is a color imbalance depending on the azimuth emitted by the light. That is, light of different colors can be seen depending on the viewing direction, and such a characteristic is inconvenient as a light source as well as a display application.
- the light emitting device shown in FIGS. 4A and 4B is an organic EL element in which a protrusion 315 is provided on the surface of a transparent substrate 305.
- an electrode 302, a light emitting layer 303, a transparent electrode 304, and a transparent substrate 305 are laminated in this order on a substrate 301, and a plurality of protrusions 315 are formed on a surface 305a of the transparent substrate 305. To do.
- protrusions 315 rectangular prisms having a width w and a height h are arranged at random positions on the transparent substrate surface 305a, as shown in FIG. 4B.
- the size of w is in the range of 0.4 to 20 ⁇ m
- the size of h is in the range of 0.4 to 10 ⁇ m
- such protrusions 315 are formed with a density in the range of 5000 to 1000000 pieces / mm 2 . .
- a voltage between the electrode 302 and the transparent electrode 304 light is emitted from the inside of the light emitting layer 303 (for example, the point S).
- the light 310d is reflected directly or after being reflected by the electrode 302, and then passes through the transparent electrode 304, and a part of the light 310d is taken out to the outside through the protrusion 315 like 310f.
- the inventor of the present application considered the reason why the light extraction efficiency was improved in the light emitting devices of FIGS. 4 (a) and 4 (b) as follows.
- the actual shape of the protrusion 315 can be processed so as to become thinner as it goes to the tip by side etching, and the protrusion 315 is naturally formed into a tapered shape without performing side etching.
- the rate is a value near the middle between the transparent substrate 305 and air. Therefore, the refractive index distribution can be gently changed equivalently. In this case, the refractive index distribution is close to the refractive index distribution shown in FIG.
- the projection 315 can partially prevent light reflection as indicated by the arrow 310e. As a result, the light extraction efficiency can be improved. Even if the size of the protrusions 315 is set to be equal to or greater than the wavelength, the protrusions 315 are arranged at random, so that interference of the extracted light can be suppressed.
- the improvement in the transmittance is limited to that by light below the critical angle. .
- the improvement of the light extraction efficiency is only about 20%, and no significant improvement can be expected.
- the inventors of the present application further studied how to reduce the amount of light totally reflected on the refracting surface and increase the amount of light that can be extracted.
- FIG. 5 schematically shows boundary conditions of the light field on the refracting surface.
- a case where light having a width W is incident on the refractive surface T is considered.
- the integration along path A that goes around the refractive surface T with respect to the electric field vector or magnetic field vector is zero.
- the width t orthogonal to the refracting surface can be made negligibly smaller than the width s along the refracting surface. Only the component along the refractive surface remains. From this relationship, it is required that the electric field vector or magnetic field vector is continuous across the refractive surface.
- the Fresnel equation is derived using this continuity relationship, and the reflection, refraction law, total reflection phenomenon, etc. are completely solved by this equation.
- the width t cannot be ignored when the light width W is reduced to several tens of times the wavelength or less.
- the circular integral A is divided into B and C (see FIG. 5C)
- the circular integral B is included in the light flux (a bundle of rays) and becomes zero. Since the remaining circular integration C has zero electric field vector or magnetic field vector outside the luminous flux, only the integral value of the path PQ in the luminous flux remains (see FIG. 5D). Accordingly, the circulation integral C is not zero, and is equivalent to light emission in the calculation circuit.
- the circular integrals C and C ′ are close to each other and the paths PQ and Q′P ′ are overlapped. The circular integration of 'is zero, and no light is emitted in the circuit.
- the circular integration C is twice the integration in the path PQ. This is equivalent to the fact that light is emitted within the circuit.
- the inventor of the present application studied the structure of the refracting surface for actually causing the phenomenon of light transmission even when exceeding the critical angle as follows.
- pinhole light (width w) is provided by providing (a) a pinhole on the boundary surface with air of the transparent substrate placed on the light emitter and shielding the rest. And (b) a case where 180-degree phase shifters 18 are randomly arranged in a grid partitioned by a width w.
- FIG. 7A is a graph showing the dependence of the transmittance t on the refractive surface on the incident angle in the structure shown in FIG.
- the wavelength of light is 0.635 ⁇ m
- light having a light quantity 1 is incident on the boundary surface with air at an angle ⁇ (angle formed with the refractive surface normal) in a transparent substrate having a refractive index of 1.457.
- the characteristic when w 20 ⁇ m, which is close to the condition of FIG. 5A, becomes almost zero when the critical angle (43.34 degrees) is exceeded.
- w is reduced to 0.4 to 1.0 ⁇ m, a large transmittance exists even if the critical angle is exceeded due to the boundary diffraction effect described in FIGS. 5 (d) and 5 (h).
- FIG. 7A shows an analysis result based on the Helmholtz wave equation (so-called scalar wave equation), and thus there is no difference between P-polarized light and S-polarized light.
- the overall light quantity increases for the following reasons.
- FIG. 7B light enters the point S on the phase shifter 18 (shown in FIG. 6) from various angles.
- FIG. 7B light enters from the negative direction of the Z axis and exits in the positive direction.
- the light 30 incident on the phase shifter 18 at an angle smaller than the critical angle is compared with the light 31 incident on the phase shifter 18 at an angle larger than the critical angle.
- the light 31 having a relatively larger incident angle than the light 30 is incident from a wide area, the amount of light increases.
- the light 30 has an incident angle smaller than the critical angle, and is emitted to the air layer side without being reflected by the phase shifter 18.
- the incident angle of the light 31 is larger than the critical angle, a part of the light 31 is reflected by the phase shifter 18 and a part of the light 31 is emitted to the air layer side by the boundary diffraction effect.
- the light 31 has a larger amount of light than the light 30, as shown in FIG. 7A, even if the transmittance decreases in the light 30 having an angle smaller than the critical angle, the incident angle larger than the critical angle.
- the light emitting device of this embodiment is an organic EL element.
- FIG. 8 shows a cross-sectional configuration of the organic EL element of the first embodiment and a state of light propagation.
- an electrode 2, a light emitting layer 3, and a transparent electrode 4 are laminated in this order on a substrate 1, and a transparent substrate (transparent substrate) that protects the transparent electrode 4 is formed on the transparent electrode 4. (Protective layer) 5 is formed.
- the substrate 1, the electrode 2, the light emitting layer 3, and the transparent electrode 4 constitute a light emitter.
- a protective layer 11 is formed on the transparent substrate 5.
- the protective layer 11 is used so that light from the light emitter enters one surface (the surface on the transparent substrate 5 side) and exits from the other surface (the surface opposite to the transparent substrate 5).
- the protective layer 11 includes a plurality of micro regions 13 (micro regions ⁇ ) on the surface opposite to the transparent substrate 5.
- FIG. 9A shows a pattern of the minute region 13 in the first embodiment.
- the microregion 13 is divided into microregions 13a and 13b (microregions ⁇ 1 and ⁇ 2).
- the fine regions 13a and 13b virtually divide the surface of the protective layer 11 opposite to the organic EL element into grids (squares) having a width w (referred to as boundary width) without any gaps.
- Each of the micro regions 13a and 13b has a structure adjacent to and surrounded by the other micro regions 13a and 13b.
- the micro regions 13 a are arranged at a ratio of 20% to 80% of all the micro regions 13.
- the micro area 13b occupies an area other than the micro area 13a in the micro area 13.
- the micro regions 13 a and 13 b are preferably arranged at a ratio of 50% of the micro regions 13.
- the micro regions 13a and 13b have a size in which the diameter of the largest circle inscribed is 0.2 ⁇ m or more and 2 ⁇ m or less.
- the micro regions 13a and the micro regions 13b are covered with micro polarizers whose transmission axes are orthogonal to each other.
- the polarizer is provided in a minute portion 13A (minute portion d1) including the minute region 13a and extending in the thickness direction, and a minute portion 13B (minute portion d2) including the minute region 13b and extending in the thickness direction.
- the vibration direction of the electric field vector of the light transmitted through the minute region 13a is orthogonal to the vibration direction of the electric field vector of the light transmitted through the minute region 13b, and the electric field vector of the light transmitted through the minute regions 13a and 13b is The orientation is discontinuous.
- the circular integral of the electric field vector of the light incident on the refracting surface is not zero, so that light is generated at the boundary between the minute region 13a and the minute region 13b (boundary diffraction effect).
- the range in which “the vibration direction of the light transmitted through the minute region 13a and the light transmitted through the minute region 13b is orthogonal” is within the range when manufacturing errors of the minute portions 13A and 13B and the vibration direction of light are measured. The case where the vibration direction deviates from the orthogonal direction due to a measurement error is also included.
- FIG. 10 schematically shows the arrangement of the polarizers 19 a and 19 b in the protective layer 11.
- the polarizers 19a and 19b have an optically anisotropic structure in the plane, and transmit only polarized components orthogonal to each other.
- the transmission axes of the polarizer 19a in each minute portion 13A are aligned with each other, and the transmission axes of the polarizer 19b in each minute portion 13B are aligned with each other. Further, the transmission axis of the polarizer 19a in the minute portion 13A and the transmission axis of the polarizer 19b in the minute portion 13B are orthogonal to each other.
- For each polarizer 19a, 19b one polarization component is transmitted and the other polarization component is blocked (or reflected).
- FIG. 9 (b) shows a wider area of the surface of the protective layer 11 than FIG. 9 (a).
- the micro area 13a is shown in black and the micro area 13b is shown in white.
- w is 0.4 ⁇ m.
- the arrangement of the micro regions 13a and 13b does not have periodicity (arranged randomly).
- the “arrangement” in this case refers to an arrangement within the surface of the protective layer 11 opposite to the organic EL element, and is not an arrangement in the thickness direction of the protective layer 11.
- the minute region 13 in which each of the minute regions 13a and 13b is arranged is a square, and the size thereof is “the diameter of the largest inscribed circle is not less than 0.2 ⁇ m and not more than 2 ⁇ m”.
- the shape and size of the minute region 13 are not “not periodic”.
- the light that diffracts such a randomly arranged pattern by the boundary diffraction effect also has a random propagation direction, so there is no light intensity distribution depending on the direction as in the light emitting device described in Patent Document 1. In addition, there is no color imbalance due to orientation. In addition, light incident from the outside (air layer side) is reflected on the surface of the transparent substrate 5, but since the reflected light is diffracted in random directions, an image of the outside does not appear, and an antireflection film or the like. This optical processing is unnecessary, and the product cost can be kept low.
- the refractive index of the air 6 is n0 and the refractive index of the transparent substrate 5 is n1
- the protective layer 11 is provided on the surface of the transparent substrate 5, even if light is incident on the point Q at an angle x equal to or greater than the critical angle ⁇ c, the light is diffracted without being totally reflected and is directed toward the air 6. The light is emitted (first light extraction).
- the extracted light quantity is proportional to the value obtained by multiplying the transmittance t shown in FIG. 7 by sin ⁇ .
- light having a light amount of 1 emitted from one point in the transparent substrate 5 is incident on the minute portions 13A and 13B at an angle ⁇ (angle formed with the refractive surface normal).
- the incident angle dependence of the first extracted light amount can be found. Further, when the light is reflected once at the protective layer 11 and then reflected by the electrode 2 and then enters the protective layer 11 again, that is, the incident angle dependency of the second extracted light amount can be obtained.
- FIG. 11 is a graph showing the light extraction efficiency of the protective layer 11 in the first embodiment.
- FIG. 11 shows the light extraction efficiency when a phase shifter that converts the phase of light by 180 degrees is placed in the minute region 13a.
- FIG. 11 summarizes the results under the same conditions as the results shown in FIG. 7 with the boundary width w of the protective layer 11 on the horizontal axis.
- FIG. 11 shows not only the first light extraction efficiency ⁇ 1 but also the second light extraction efficiency ⁇ 2.
- the second light extraction efficiency ⁇ 2 is reflected by the protective layer 13 on the assumption that there is no light attenuation in the reciprocation such as absorption by the transparent electrode 4 and reflection loss by the electrode 2, and after reflecting the electrode 2, the protective layer 13 is again reflected. Is the light extraction efficiency in the case of incident on the light.
- the boundary width w is increased, the first and second light extraction efficiencies gradually approach 0.25 and 0.00, respectively, and when the boundary width w is decreased from 0.3 ⁇ m, only the second time. In addition, the first light extraction efficiency becomes zero (the reason for this has already been described with reference to FIG. 5E).
- the second light extraction efficiency considering the light attenuation in the round trip is ⁇ ⁇ ⁇ 2.
- the light extraction is repeated infinitely instead of once and twice, and if the relationship is a geometric sequence, the first time is ⁇ 1 and the second time is ⁇ ⁇ ⁇ 2, the nth time is ⁇ 1 ⁇ ( ⁇ ⁇ ⁇ 2 / ⁇ 1) n-1 can be expected. Accordingly, the total light extraction up to the n-th time is as shown in the following (Equation 6). Infinite times, asymptotically approaches (Formula 7) below.
- w is set to 0.3 ⁇ m or more and 2.00 ⁇ m or less (in general terms, the diameter of the largest circle inscribed in the minute region 13 is set to 0.3 ⁇ m or more and 2 ⁇ m or less)
- the light extraction efficiency can be greatly improved.
- w in the smallest region may be 0.2 ⁇ m due to a manufacturing error. From this result, in order to improve the light extraction efficiency, it is preferable to set w to 0.2 ⁇ m or more and 2 ⁇ m or less.
- w is 0.4 ⁇ m or more and 0.8 ⁇ m or less because the light extraction efficiency is maintained in a high range.
- Table 1 shows values of light extraction efficiency (first time, second time, and total light extraction efficiency ⁇ 1, ⁇ 2, and ⁇ , respectively) calculated using the probability P1 in which the minute region 13a of the minute region 13 is present as a parameter. ).
- the light extraction efficiency decreases as the value of P1 deviates from 0.5, but the degree of decrease is small in the range of 0.8 ⁇ P1 ⁇ 0.2. Therefore, as long as the present embodiment complies with the pattern generation rule in the range of 0.8 ⁇ P1 ⁇ 0.2, the light extraction efficiency is high.
- the pattern of the polarizers 19a and 19b as shown in FIG. 10 can be formed by using, for example, a method of forming a patterned photonic crystal.
- a method of forming a patterned photonic crystal For example, pages 795 to 798 of Journal of Precision Engineering, Vol. 74, No. 8 (2008) (Hereinafter referred to as technical literature).
- a stripe-shaped uneven pattern having a pitch of several hundred nm is formed by a lithography technique for each square region on the base substrate.
- the stripe in the square where the micro area 13a is to be formed and the stripe in the square where the micro area 13b is to be formed are formed in different directions.
- a laminated structure of about 20 periods (40 layers) is formed.
- stacking while etching the surface with argon ions, stacking can be performed while forming a slope along the unevenness of the base substrate.
- the thickness of this polarizer is about 0.5 ⁇ m, and there is almost no difference in thickness between the portion where the microregion 13a is formed and the portion where the microregion 13b is formed.
- the material to be laminated is not limited to the above, and for example, SiO 2 and Si 3 N 4 , SiO 2 and TiO 2 , SiO 2 and NbO 2 , SiO 2 and Si may be used.
- the size of the square region is about 5 ⁇ m square. If a fine processing technique such as an electron beam lithography technique is used as a lithography method for the base substrate, it is possible to perform processing in an area that is an order of magnitude smaller.
- a transparent adjustment layer 15 for adjusting the light transmittance in the reciprocation of light between the transparent substrate 5 and the electrode 2 is placed on the transparent electrode 4.
- the transparent substrate 5 is placed on the adjustment layer 15 (that is, an organic EL element including the adjustment layer 15 can be referred to as a light emitter).
- the refractive index n1 of the transparent substrate 5 is smaller than the refractive index n1 ′ of the adjustment layer 15, there is a boundary surface 15a where total reflection occurs between the transparent substrate 5 and the adjustment layer 15, and in particular n1′ ⁇ n1. If> 0.1, the effect cannot be ignored.
- the light emitted from the point S inside the light emitting layer 3 having a refractive index n2 passes through the transparent electrode 4 directly or after reflecting the electrode 2 and through the adjusting layer 15 having the refractive index n1 ′. Then, the light is refracted at a point P ′ on the boundary surface 15a, passes through the transparent substrate 5 having a refractive index n1, and is emitted to the air 6 side through the point P on the protective layer 11.
- n1 ' may be smaller than n2, but in this case, total reflection occurs between the transparent electrode 4 and the adjustment layer 15.
- the protective layer 11 of the present embodiment is formed on the boundary surface with the air 6 in the transparent substrate 5, light exceeding the critical angle can be taken out to the air 6 side. However, total reflection also occurs at the boundary surface 15a due to the relationship of n1 '> n1. In other words, when the light beam is incident on the point Q ′ having a larger incident angle than that incident on the point P ′, the light is totally reflected from the electrode 2 and cannot be extracted to the air 6 side.
- the protective layer 11 ′ in this embodiment may be provided on the boundary surface between the adjustment layer 15 and the transparent substrate 5. Thereby, incident light exceeding the critical angle on this surface can be extracted to the air 6 side.
- FIG. 13 has the complexity of forming the protective layers 11 and 11 ′ having projections and depressions in a double manner, a material having a low refractive index can be used for the transparent substrate 5, so that the selection range of the material is widened.
- Equation 7 indicates that the light extraction efficiency increases if the light transmittance ⁇ in the round trip between the transparent substrate 5 and the electrode 2 is large.
- the actual light-emitting layer 3 is surrounded by a plurality of transparent layers such as the adjustment layer 15 described above in addition to the electrode 2 and the transparent electrode 4, but the film design (the refractive index and thickness of the film including the light-emitting layer 3) Is determined so that the aforementioned light transmittance ⁇ is maximized.
- the film design the refractive index and thickness of the film including the light-emitting layer 3
- the influence of reflection on the surface of the transparent substrate 5 can be ignored, and can be treated virtually with a reflectance of 0% and a transmittance of 100%.
- light is emitted from the transparent substrate 5, and this light is reciprocated multiple times to and from the multilayer film including the light emitting layer 3, so that the amount of overlap of the complex light amplitude returning to the transparent substrate 5 is maximized.
- the refractive index and thickness of each film are determined.
- each of the micro-parts 13A and 13B is provided with 1 ⁇ 2 wavelength with different optical axes. It has a two-dimensional wave plate array structure in which plates 20a and 20b are formed (FIG. 14).
- the wave plates 20a and 20b in the minute portions 13A and 13B are arranged so that the respective optical axis directions form an angle of approximately 45 degrees.
- the angle formed by the vibration direction of the electric field vector of the linearly polarized light of the incident light and one optical axis of the half-wave plate is ⁇ . Since the half-wave plate has the effect of rotating the polarization plane of the incident light by 2 ⁇ , the oscillation direction of the electric field vector of the emitted light is inclined by ⁇ -2 ⁇ degrees, that is, ⁇ degrees with respect to the optical axis of the crystal. . At this time, the other optical axis of the half-wave plate is inclined by ( ⁇ + 45) degrees from the vibration direction of the electric field vector of the linearly polarized light of the incident light.
- the oscillation direction of the electric field vector of the emitted light is inclined by ⁇ 2 ( ⁇ + 45) degrees, that is, ( ⁇ 90) degrees with respect to the optical axis of the crystal. From this result, it can be seen that when light is incident on the half-wave plates placed in directions where the optical axes are different from each other by 45 degrees, the polarization axes of the light emitted from the respective wave plates are orthogonal. That is, in this embodiment, the same effect as that obtained when a phase difference of ⁇ is given can be obtained.
- the phase difference between the light emitted from the minute region 13a and the light emitted from the minute region 13b is ⁇
- the phase of the electric field vector is discontinuous with respect to the light transmitted through the minute regions 13a and 13b.
- the circular integral of the electric field vector of the light incident on the refracting surface is not zero, so that light is generated at the boundary between the minute region 13a and the minute region 13b (boundary diffraction effect).
- phase difference is compared with light having the same wavelength.
- the protective layer 11 has a phase difference of light having a wavelength near the center (green or red light having a wavelength of around 600 nm) in the visible light wavelength range (about 380 nm to about 780 nm) emitted from the organic EL. Designed to. However, the design may be performed based on light of any wavelength among light of various wavelengths emitted from the organic EL element. Depending on the wavelength range of light emitted from the light emitting element, the design may be performed based on light having a wavelength of 400 nm or 500 nm.
- the manufacturing error of the minute portions 13A and 13B and the vibration direction of the electric field vector of the light are measured.
- the case where the phase difference deviates from ⁇ due to measurement error is also included.
- the wave plate can also be manufactured by controlling the thickness to be stacked (the thickness of each layer and the stacking cycle) using the same manufacturing method as the polarizer array in the first embodiment. It is disclosed in the technical literature described in the first embodiment that a wave plate can be formed using a method for forming a patterned photonic crystal.
- a stripe-shaped uneven pattern having a pitch of several hundred nm is formed by a lithography technique for each square region in the base substrate.
- the stripe in the square where the micro area 13a is to be formed and the stripe in the square where the micro area 13b is to be formed are formed in 45 degrees different directions.
- SiO 2 and Ti 2 O 5 are alternately supplied on the base substrate to form a laminated structure of about 10 periods (20 layers).
- stacking can be performed while forming a slope along the unevenness of the base substrate.
- the thickness of this polarizer is about 3 ⁇ m, and there is almost no difference in thickness between the portion where the microregion 13a is formed and the portion where the microregion 13b is formed.
- the size of the square region is about 5 ⁇ m square. If a microfabrication technique such as an electron beam lithography technique is used as a lithography method for the base substrate, it is possible to perform processing in an area that is an order of magnitude smaller.
- the transmissive plate 21b and the light shielding plate 21a are laid on the micro portions 13A and 13B. It has a two-dimensional array structure (FIG. 15).
- the magnitude of the electric field vector is discontinuous with respect to the light transmitted through the minute regions 13a and 13b.
- the circular integral of the electric field vector of the light incident on the refracting surface is not zero, so that light is generated at the boundary between the minute region 13a and the minute region 13b (boundary diffraction effect).
- the same light extraction characteristics as those of the pinhole and the phase shifter that is, the same effect as that obtained when a phase difference of ⁇ is given between the minute portion 13A and the minute portion 13B can be obtained. .
- the protective layer 11 of this embodiment can be manufactured by the following method.
- a pattern may be formed on a metal on a glass substrate by electron beam exposure and a dry etching process so as to form a mask used for photolithography.
- the portion where the metal is removed and the glass substrate is exposed is the transmission plate 21b, and the portion where the metal remains is the light shielding plate 21a.
- a pattern size of 1 ⁇ m or less can be sufficiently produced.
- a fourth embodiment of a sheet (protective layer) according to the present invention will be described with reference to FIG.
- the fourth embodiment is the same as the first embodiment except that the pattern of the minute portions 13A and 13B in the protective layer 11 is different from that of the first embodiment.
- the description of the configuration common to the first embodiment is omitted here.
- FIG. 16A is a diagram showing a pattern of the first protective layer 23 in the present embodiment.
- the first protective layer 23 is divided into equilateral triangles (microregions 13) each having a length w, and each microregion 13 is an ⁇ region 23a (microregion 13a).
- ⁇ region 23b (micro region 13b), each having a ratio of 50%, ⁇ region 23a and ⁇ region 23b are randomly assigned.
- w is 3.5 ⁇ m or less.
- FIG. 16B is a diagram showing a pattern of the second protective layer 33 in the present embodiment.
- the second protective layer 33 is divided into regular hexagons (small regions 13) each having a length w, and each figure is an ⁇ region 33a (small region 13a).
- the ⁇ region 33a and the ⁇ region 33b are randomly assigned with the ratio of whether it is the ⁇ region 33b (microregion 13b) being 50%.
- w is 1.15 ⁇ m or less.
- the size of a figure generally requires that the diameter of the largest circle inscribed in the figure is 0.2 ⁇ m or more and 2 ⁇ m or less.
- any of a polarizer as in the first embodiment, a wave plate as in the second embodiment, a transmissive plate and a light shielding plate as in the third embodiment is used. May be.
- the pattern shape of the present embodiment is not limited to a regular triangle or a regular hexagon, and may be an arbitrary polygon as long as the same figure can be divided into planes without gaps.
- the minute portions 13A and 13B in the actual processed body are not strictly squares, regular triangles, regular hexagons, or rounded corners.
- the corner of the minute region adjacent to the minute region with rounded corners is deformed accordingly. In such a case, it goes without saying that the characteristics are not deteriorated and the same effect can be obtained.
- the light emission position moves away from the position of the light emitting point S as the number of light extraction increases.
- the transparent substrate 5 on which the protective layer 13 is formed is formed to be as thin as several ⁇ m, and an air layer is sandwiched between the transparent substrate 5 and 0.2 mm to 0 mm.
- the structure covered with the protective substrate 14 of about 5 mm is conceivable.
- a transparent material having a low refractive index such as airgel may be used on the protective layer 13 instead of the air layer.
- the substrate 1 to the protective substrate 14 are integrated, the device As a high stability.
- the protective layer 11 is formed only on one surface side (upper surface side) of the transparent substrate 5, but a similar structure may be formed on both surface sides of the transparent substrate 5. Further, a general diffraction grating 11 ′ may be disposed between the protective layer 11 and the light emitting point S.
- the transparent substrate 5 is formed into a film shape
- a protective layer 11 is formed on the front surface
- a film 11 ′ having a diffraction grating or a film 11 ′′ having a surface structure of another specification is formed on the back surface. It can be formed and bonded to the light emitter through the adhesive layer 22.
- the adhesive layer 22 If the refractive index of the transparent substrate 5 is small and the difference in refractive index from the light emitting layer 3 is 0.1 or more, the adhesive layer 22 If the material is selected to be 0.1 or less than the refractive index of the light emitting layer 3, almost no total reflection occurs at the interface between the adhesive layer 22 and the light emitting layer 3. Further, A film 11 ′′ having a surface structure (or a film 11 ′ having a diffraction grating) and a total reflection generated on the refractive surface between the transparent substrate 5 and the refractive surface between the transparent substrate 5 and the air 6; and This can be avoided by the protective layer 11.
- the pattern of the protective layer 11 in the first to fourth embodiments is different from the surface state such as frosted glass or roughened surface, or the surface state shown in the light emitting device described in Patent Document 2.
- the pattern of the protective layer in the first to fourth embodiments has a structure in which the surface is divided into grid areas having a width w and an optically discontinuous boundary is provided for each eye, for example, 1: 1.
- the ratio is assigned.
- This pattern has a scale of a specific width w and a characteristic of a specific minute area, and the ratio of the total area of one to the total area of the other is also in a 1: 1 relationship.
- the surface state such as frosted glass or roughened surface does not have an inherent width w (at least under the condition of w ⁇ 0.05 ⁇ m), and the shape of the micro region is indefinite and has an area of The ratio is not necessarily 1: 1.
- the ratio in the said embodiment is not a random pattern which does not have periodicity completely, but can be said to be a pattern along a certain rule. That is, in the protective layer 11 in the first to fourth embodiments, “not having periodicity” is “two-dimensional arrangement of the fine regions ⁇ 1 and ⁇ 2”, and the size of each fine region ⁇ is large. The sheath shape is not “not periodic”.
- the phenomenon caused by the surface shape in the first to fourth embodiments is one of diffraction phenomena.
- a light beam that is virtually refracted with respect to a flat reference surface that averages the surface shape is defined as 0th-order diffracted light (not shown in the case of total reflection), and this light is used as a reference for orientation.
- 0th-order diffracted light not shown in the case of total reflection
- higher-order diffracted light is generated in the shifted direction.
- the propagation direction of diffracted light other than the 0th order is random.
- it is not a diffraction phenomenon but a refraction phenomenon that is caused by frosted glass or surface roughening.
- the orientation of the surface normal is random on the refracted refracting surface, so that the direction of refraction is also random. It is only becoming. That is, when the pattern shape in the first to fourth embodiments is formed on a parallel plate and viewed through, the outline of the opposite image can be clearly seen. This is because 0th-order diffracted light always exists in the light that is diffracted and separated by the surface shape, and this light maintains the contour of the image on the opposite side. On the other hand, in frosted glass or roughened surface, there is no light corresponding to the 0th-order diffracted light, and the outline of the image on the opposite side becomes blurred when viewed through.
- Patent Document 2 light is simply described as “irradiated straightly into the air” by the protrusions on the surface, and there is no description of diffraction.
- the word “obedient” can be interpreted as “following Snell's law (the law of refraction), which is a simpler principle”. In that sense, it can be understood that the protrusions on the surface of Patent Document 2 fall into the same category as polished glass and surface roughening, and can be said to be completely different from the present invention.
- Patent Document 2 The feature of the technique disclosed in Patent Document 2 is that a plurality of transparent protrusions are arranged completely at random on a transparent insulating substrate, and each region is one of minute regions having the same shape as in the present application.
- the feature of making the abundance of two or more aggregates and a specific proportion thereof is neither disclosed nor suggested.
- the structure in which one and the other are interchanged is substantially the same as the original structure, but this is not the case with the light emitting device described in Patent Document 2.
- the inventors of the present application have found for the first time that the light extraction effect is remarkable due to the characteristics of the present invention, and Patent Document 2 does not describe the remarkable effect as in the present invention.
- the boundary diffraction effect occurs at a boundary where the direction, phase or magnitude of the electric field vector of light is discontinuous, in order to maximize this effect, the direction, phase or magnitude of the electric field vector of light is not continuous. It is preferable to maximize the appearance ratio of the boundary. If the refracting surface is divided into innumerable minute regions, and the direction, phase, or magnitude of the electric field vector of light becomes discontinuous at the boundary between the minute regions, the aforementioned appearance ratio is maximized by two conditions. The first condition is that the area of each micro area is as uniform as possible. The second condition is that there is a boundary where the direction, phase, or magnitude of the electric field vector of light is discontinuous between adjacent micro areas. It exists.
- the boundary where the direction, phase, or size of the signal is discontinuous increases.
- the area of each micro area is aligned as much as possible, and at least the area of each micro area is 0.5 to 1.5 times the reference area (the maximum of the circles inscribed in the micro area) If the diameter of the material falls within the range of 0.7 to 1.3 times the standard diameter, the appearance ratio of the boundary line between the microregions is maximized.
- the first to fourth embodiments comply with this condition. Even if the division into minute regions can be maximized, the effect is diminished if the direction, phase, or magnitude of the electric field vector of light is aligned between adjacent minute regions. Therefore, it is necessary to randomly assign the minute regions so that there is a boundary where the direction, phase, or magnitude of the electric field vector of light is discontinuous between adjacent minute regions. That is, the light-emitting device of the above embodiment is extracted not by the effect of antireflection like the light-emitting device described in Patent Document 2 (although this effect is included) but by the effect of maximizing the boundary diffraction effect. Increased efficiency has been realized.
- the first to fourth embodiments are not independently established, but a part of each may be combined to form a new example.
- the organic electroluminescence element has been described as an example.
- the present invention can be applied to any element as long as it emits light in a medium having a refractive index larger than 1.
- the medium from which the light emitting device emits light is not limited to air.
- the present invention can be applied when the refractive index of the transparent substrate is larger than the refractive index of the medium with which the transparent substrate is in contact, particularly 0.1 or more.
- the light emitting device greatly improves the light extraction efficiency, and thus is useful as a display or a light source.
Abstract
Description
これはスネルの法則そのものである。一方、回折光線の方位を与えるベクトル210dの方位角φ’(屈折面法線となす角)は次の(数5)で与えられる。
以下、本発明によるシート(保護層)および発光装置の第1の実施形態を図8から図13に基づいて説明する。本実施形態の発光装置は、有機EL素子である。
以下、本発明によるシート(保護層)および発光装置の第2の実施形態を図14に基づいて説明する。なお、第2の実施形態は、保護層11における微小部分13A,13Bのパターンが第1の実施形態と違うだけで、他の構成は全て第1の実施形態と同じである。第1の実施形態と共通の構成については、ここではその説明を省略する。
以下、本発明によるシート(保護層)および発光装置の第3の実施形態を図15に基づいて説明する。なお、第3の実施形態は、保護層11における微小部分13A,13Bのパターンが第1の実施形態と違うだけで、他の構成は全て第1の実施形態と同じである。第1の実施形態と共通の構成については、ここではその説明を省略する。
以下、本発明によるシート(保護層)の第4の実施形態を図16に基づいて説明する。なお、第4の実施形態は、保護層11における微小部分13A、13Bのパターンが第1の実施形態と違うだけで、他の構成は全て第1の実施形態と同じである。第1の実施形態と共通の構成については、ここではその説明を省略する。
上述の実施形態は本発明の例示であって、本発明はこれらの例に限定されない。
2 電極
3 発光層
4 透明電極
5 透明基板
6 空気
11 保護層
13a、13b 微小領域
13A、13B 微小部分
19a、19b 偏光子
20a、20b 1/2波長板
21a 透過板
21b 遮光板
23a、33a α領域
23b、33b β領域
S 発光点
Claims (11)
- 発光体からの光が一方の面に入射し、他方の面から出射するように用いられるシートであって、
前記他方の面に、内接する最大の円の直径が0.2μm以上2μm以下の複数の微小領域δを備え、
前記複数の微小領域δのうちの個々の微小領域δは、前記複数の微小領域δのうちの他の複数の微小領域δによって隣接且つ囲繞されており、
前記複数の微小領域δは、前記複数の微小領域δから20%以上80%以下の割合でランダムに選ばれた複数の微小領域δ1と、それ以外の複数の微小領域δ2とからなり、
前記複数の微小領域δ1を透過した光と、前記複数の微小領域δ2を透過した光との位相差はπである、シート。 - 前記複数の微小領域δ1のそれぞれを含み、厚さ方向に延びる複数の微小部分d1と、
前記複数の微小領域δ2のそれぞれを含み、厚さ方向に延びる複数の微小部分d2とをさらに備え、
前記複数の微小部分d1および前記複数の微小部分d2のそれぞれには、光軸の揃った1/2波長板が配置され、
前記複数の微小部分d1の1/2波長板の光軸方位と、前記複数の微小部分d2の1/2波長板の光軸方位とが45度の角度で配置される、請求項1に記載のシート。 - 発光体からの光が一方の面に入射し、他方の面から出射するように用いられるシートであって、
前記他方の面に、内接する最大の円の直径が0.2μm以上2μm以下の複数の微小領域δを備え、
前記複数の微小領域δのうちの個々の微小領域δは、前記複数の微小領域δのうちの他の複数の微小領域δによって隣接且つ囲繞されており、
前記複数の微小領域δは、前記複数の微小領域δから20%以上80%以下の割合でランダムに選ばれた複数の微小領域δ1と、それ以外の複数の微小領域δ2とからなり、
前記複数の微小領域δ1のそれぞれを含み、厚さ方向に延びる複数の微小部分d1と、
前記複数の微小領域δ2のそれぞれを含み、厚さ方向に延びる複数の微小部分d2とをさらに備え、
前記複数の微小部分d1および前記複数の微小部分d2のそれぞれには、透過軸の揃った偏光子が配置され、
前記複数の微小部分d1に配置される偏光子の透過軸と、前記複数の微小部分d2を構成する偏光子の透過軸とは直交する、シート。 - 発光体からの光が一方の面に入射し、他方の面から出射するように用いられるシートであって、
前記他方の面に、内接する最大の円の直径が0.2μm以上2μm以下の複数の微小領域δを備え、
前記複数の微小領域δのうちの個々の微小領域δは、前記複数の微小領域δのうちの他の複数の微小領域δによって隣接且つ囲繞されており、
前記複数の微小領域δは、前記複数の微小領域δから20%以上80%以下の割合でランダムに選ばれた複数の微小領域δ1と、それ以外の複数の微小領域δ2とからなり、
前記複数の微小領域δ1のそれぞれを含み、厚さ方向に延びる複数の微小部分d1と、
前記複数の微小領域δ2のそれぞれを含み、厚さ方向に延びる複数の微小部分d2とをさらに備え、
前記複数の微小部分d1および前記複数の微小部分d2のうちのいずれか一方には、遮光面が設けられている、シート。 - 前記複数の微小領域δ1および前記複数の微小領域δ2は多角形であって、
前記複数の微小領域δ1および前記複数の微小領域δ2は互いに合同な形状である、請求項1から4のいずれかに記載のシート。 - 発光体と、前記発光体における発光面の上に設けられた保護層とを備えた発光装置であって、
前記保護層において前記発光面側と反対側の面に、内接する最大の円の直径が0.2μm以上2μm以下の複数の微小領域δを備え、
前記複数の微小領域δのうちの個々の微小領域δは、前記複数の微小領域δのうちの他の複数の微小領域δによって隣接且つ囲繞されており、
前記複数の微小領域δは、前記複数の微小領域δから20%以上80%以下の割合でランダムに選ばれた複数の微小領域δ1と、それ以外の複数の微小領域δ2とからなり、
前記複数の微小領域δ1を透過した光と、前記複数の微小領域δ2を透過した光との位相差はπであり、
前記保護層のうち前記発光層側とは反対側の面は、前記保護層の屈折率よりも低い屈折率を有する媒質と接する、発光装置。 - 前記複数の微小領域δ1のそれぞれを含み、厚さ方向に延びる複数の微小部分d1と、
前記複数の微小領域δ2のそれぞれを含み、厚さ方向に延びる複数の微小部分d2とをさらに備え、
前記複数の微小部分d1および前記複数の微小部分d2のそれぞれには、光軸の揃った1/2波長板が配置され、
前記複数の微小部分d1の1/2波長板の光軸方位と、前記複数の微小部分d2の1/2波長板の光軸方位とが45度の角度で配置される、請求項6に記載の発光装置。 - 発光体と、前記発光体における発光面の上に設けられた保護層とを備えた発光装置であって、
前記保護層において前記発光面側と反対側の面に、内接する最大の円の直径が0.2μm以上2μm以下の複数の微小領域δを備え、
前記複数の微小領域δのうちの個々の微小領域δは、前記複数の微小領域δのうちの他の複数の微小領域δによって隣接且つ囲繞されており、
前記複数の微小領域δは、前記複数の微小領域δから20%以上80%以下の割合でランダムに選ばれた複数の微小領域δ1と、それ以外の複数の微小領域δ2とからなり、
前記保護層のうち前記発光層側とは反対側の面は、前記保護層の屈折率よりも低い屈折率を有する媒質と接し、
前記複数の微小領域δ1のそれぞれを含み、厚さ方向に延びる複数の微小部分d1と、
前記複数の微小領域δ2のそれぞれを含み、厚さ方向に延びる複数の微小部分d2とをさらに備え、
前記複数の微小部分d1および前記複数の微小部分d2のそれぞれには、透過軸の揃った偏光子が配置され、
前記複数の微小部分d1に配置される偏光子の透過軸と、前記複数の微小部分d2を構成する偏光子の透過軸とは直交する、発光装置。 - 発光体と、前記発光体における発光面の上に設けられた保護層とを備えた発光装置であって、
前記保護層において前記発光面側と反対側の面に、内接する最大の円の直径が0.2μm以上2μm以下の複数の微小領域δを備え、
前記複数の微小領域δのうちの個々の微小領域δは、前記複数の微小領域δのうちの他の複数の微小領域δによって隣接且つ囲繞されており、
前記複数の微小領域δは、前記複数の微小領域δから20%以上80%以下の割合でランダムに選ばれた複数の微小領域δ1と、それ以外の複数の微小領域δ2とからなり、
前記保護層のうち前記発光層側とは反対側の面は、前記保護層の屈折率よりも低い屈折率を有する媒質と接し、
前記複数の微小領域δ1のそれぞれを含み、厚さ方向に延びる複数の微小部分d1と、
前記複数の微小領域δ2のそれぞれを含み、厚さ方向に延びる複数の微小部分d2とをさらに備え、
前記複数の微小部分d1および前記複数の微小部分d2のうちのいずれか一方には、遮光面が設けられている、発光装置。 - 前記媒質は空気である、請求項6から9のいずれかに記載の発光装置。
- 前記媒質はエアロゲルである、請求項6から9のいずれかに記載の発光装置。
Priority Applications (3)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US13/057,297 US8227966B2 (en) | 2008-12-26 | 2009-12-21 | Sheet and light emitting apparatus |
JP2010543835A JP5658569B2 (ja) | 2008-12-26 | 2009-12-21 | シート及び発光装置 |
CN200980130652.4A CN103038677B (zh) | 2008-12-26 | 2009-12-21 | 片材及发光装置 |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2008335001 | 2008-12-26 | ||
JP2008-335001 | 2008-12-26 |
Publications (1)
Publication Number | Publication Date |
---|---|
WO2010073585A1 true WO2010073585A1 (ja) | 2010-07-01 |
Family
ID=42287234
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/JP2009/007063 WO2010073585A1 (ja) | 2008-12-26 | 2009-12-21 | シート及び発光装置 |
Country Status (4)
Country | Link |
---|---|
US (1) | US8227966B2 (ja) |
JP (1) | JP5658569B2 (ja) |
CN (1) | CN103038677B (ja) |
WO (1) | WO2010073585A1 (ja) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2013084442A1 (ja) * | 2011-12-07 | 2013-06-13 | パナソニック株式会社 | シート及び発光装置 |
Families Citing this family (14)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2010131440A1 (ja) * | 2009-05-12 | 2010-11-18 | パナソニック株式会社 | シート及び発光装置 |
JP6025367B2 (ja) * | 2011-05-12 | 2016-11-16 | キヤノン株式会社 | 有機el素子 |
US9257676B2 (en) * | 2012-12-18 | 2016-02-09 | Pioneer Corporation | Light-emitting device |
CN105940494A (zh) * | 2014-02-28 | 2016-09-14 | 松下知识产权经营株式会社 | 发光器件以及发光装置 |
CN105940508B (zh) | 2014-02-28 | 2019-01-11 | 松下知识产权经营株式会社 | 发光器件以及发光装置 |
US10182702B2 (en) | 2015-03-13 | 2019-01-22 | Panasonic Intellectual Property Management Co., Ltd. | Light-emitting apparatus including photoluminescent layer |
JP6569856B2 (ja) | 2015-03-13 | 2019-09-04 | パナソニックIpマネジメント株式会社 | 発光装置および内視鏡 |
US10031276B2 (en) | 2015-03-13 | 2018-07-24 | Panasonic Intellectual Property Management Co., Ltd. | Display apparatus including photoluminescent layer |
JP2016171228A (ja) | 2015-03-13 | 2016-09-23 | パナソニックIpマネジメント株式会社 | 発光素子、発光装置および検知装置 |
JP2017003697A (ja) | 2015-06-08 | 2017-01-05 | パナソニックIpマネジメント株式会社 | 発光素子および発光装置 |
JP6760282B2 (ja) * | 2015-07-07 | 2020-09-23 | 凸版印刷株式会社 | 経皮投与デバイス |
US10359155B2 (en) | 2015-08-20 | 2019-07-23 | Panasonic Intellectual Property Management Co., Ltd. | Light-emitting apparatus |
JP6719094B2 (ja) | 2016-03-30 | 2020-07-08 | パナソニックIpマネジメント株式会社 | 発光素子 |
US10890778B2 (en) * | 2019-06-11 | 2021-01-12 | Facebook Technologies, Llc | Optical system having an improved signal-to-noise ratio of eye-tracking |
Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS63314503A (ja) * | 1987-06-18 | 1988-12-22 | Nippon Telegr & Teleph Corp <Ntt> | 偏光子及びその作製方法 |
JP2000266936A (ja) * | 1999-03-19 | 2000-09-29 | Nitto Denko Corp | 広視野角偏光板及び液晶表示装置 |
JP2001059948A (ja) * | 1999-06-15 | 2001-03-06 | Arisawa Mfg Co Ltd | 3d映像表示体の製造方法及び3d映像表示体形成用のフィルム |
JP2002359068A (ja) * | 2001-05-31 | 2002-12-13 | Seiko Epson Corp | Elデバイス、elディスプレイ、el照明装置およびこれを用いた液晶装置、並びに電子機器 |
JP2008276940A (ja) * | 2008-08-12 | 2008-11-13 | Seiko Instruments Inc | 記録媒体および光情報記録再生装置 |
Family Cites Families (10)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS529452A (en) * | 1975-07-11 | 1977-01-25 | Matsushita Electric Ind Co Ltd | Diffusion plate |
JPS6053841B2 (ja) * | 1975-07-18 | 1985-11-27 | 松下電器産業株式会社 | 拡散板 |
JP2991183B2 (ja) | 1998-03-27 | 1999-12-20 | 日本電気株式会社 | 有機エレクトロルミネッセンス素子 |
US6236439B1 (en) * | 1998-04-20 | 2001-05-22 | Nitto Denko Corporation | Wide viewing angle polarizing plate and liquid crystal display |
TWI257828B (en) * | 2001-05-31 | 2006-07-01 | Seiko Epson Corp | EL device, EL display, EL illumination apparatus, liquid crystal apparatus using the EL illumination apparatus and electronic apparatus |
JP4027164B2 (ja) * | 2002-06-21 | 2007-12-26 | 株式会社日立製作所 | 表示装置 |
JP2004273122A (ja) | 2003-03-04 | 2004-09-30 | Abel Systems Inc | 面発光装置 |
JP2005266188A (ja) | 2004-03-18 | 2005-09-29 | Nikon Corp | 拡散素子及び照明装置 |
JP2006236748A (ja) * | 2005-02-24 | 2006-09-07 | Konica Minolta Holdings Inc | 有機電界発光装置 |
US7982396B2 (en) * | 2007-06-04 | 2011-07-19 | Global Oled Technology Llc | Light-emitting device with light-scattering particles and method of making the same |
-
2009
- 2009-12-21 WO PCT/JP2009/007063 patent/WO2010073585A1/ja active Application Filing
- 2009-12-21 US US13/057,297 patent/US8227966B2/en not_active Expired - Fee Related
- 2009-12-21 JP JP2010543835A patent/JP5658569B2/ja not_active Expired - Fee Related
- 2009-12-21 CN CN200980130652.4A patent/CN103038677B/zh not_active Expired - Fee Related
Patent Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS63314503A (ja) * | 1987-06-18 | 1988-12-22 | Nippon Telegr & Teleph Corp <Ntt> | 偏光子及びその作製方法 |
JP2000266936A (ja) * | 1999-03-19 | 2000-09-29 | Nitto Denko Corp | 広視野角偏光板及び液晶表示装置 |
JP2001059948A (ja) * | 1999-06-15 | 2001-03-06 | Arisawa Mfg Co Ltd | 3d映像表示体の製造方法及び3d映像表示体形成用のフィルム |
JP2002359068A (ja) * | 2001-05-31 | 2002-12-13 | Seiko Epson Corp | Elデバイス、elディスプレイ、el照明装置およびこれを用いた液晶装置、並びに電子機器 |
JP2008276940A (ja) * | 2008-08-12 | 2008-11-13 | Seiko Instruments Inc | 記録媒体および光情報記録再生装置 |
Cited By (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2013084442A1 (ja) * | 2011-12-07 | 2013-06-13 | パナソニック株式会社 | シート及び発光装置 |
CN103262649A (zh) * | 2011-12-07 | 2013-08-21 | 松下电器产业株式会社 | 薄板以及发光装置 |
JP5307307B1 (ja) * | 2011-12-07 | 2013-10-02 | パナソニック株式会社 | シート及び発光装置 |
US8779424B2 (en) | 2011-12-07 | 2014-07-15 | Panasonic Corporation | Sheet and light-emitting device |
CN103262649B (zh) * | 2011-12-07 | 2015-10-07 | 松下电器产业株式会社 | 薄板以及发光装置 |
Also Published As
Publication number | Publication date |
---|---|
JP5658569B2 (ja) | 2015-01-28 |
US8227966B2 (en) | 2012-07-24 |
CN103038677A (zh) | 2013-04-10 |
US20110133624A1 (en) | 2011-06-09 |
CN103038677B (zh) | 2015-02-18 |
JPWO2010073585A1 (ja) | 2012-06-07 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
JP5658569B2 (ja) | シート及び発光装置 | |
JP4346680B2 (ja) | 発光装置 | |
JP5450450B2 (ja) | シート及び発光装置 | |
WO2010131430A1 (ja) | シート及び発光装置 | |
US7722194B2 (en) | Optical element having a reflected light diffusing function and a polarization separation function and a projection display device | |
TWI737204B (zh) | 用於擴增或虛擬實境之改良角均勻性波導 | |
JP5450449B2 (ja) | 光学シート、発光装置および光学シートの製造方法 | |
JP2009015305A (ja) | 光学素子及び投写型表示装置 | |
JP5511674B2 (ja) | シートおよび発光装置 | |
WO2019146545A1 (ja) | 拡散板及び光学機器 | |
JP2008170679A (ja) | 光束分岐素子および光束干渉光学系および光束干渉露光装置 | |
JP2019139163A (ja) | 拡散板、拡散板の設計方法、表示装置、投影装置及び照明装置 | |
CN110764265A (zh) | 一种近眼导光组件、显示装置 | |
JP2015143756A (ja) | 光学シートおよび発光装置 | |
JP2010101965A (ja) | 光学素子及び表示装置 | |
JP2019028083A (ja) | 光学素子 | |
JP2013210494A (ja) | 光拡散フィルム、偏光板、及び液晶表示装置 | |
JP4574252B2 (ja) | 三次元周期構造体、光学素子、及び光学製品 | |
KR102168744B1 (ko) | 와이어 그리드 편광자 | |
JP6798768B2 (ja) | 偏光解消板及びその製造方法、並びにそれを用いた光学機器及び液晶表示装置 | |
JP2020016906A (ja) | 偏光解消素子及びその製造方法、並びにそれを用いた光学機器及び液晶表示装置 | |
JP2007065175A (ja) | 偏光子 | |
JP2017026824A (ja) | 偏光解消素子及びその製造方法、並びにそれを用いた光学機器及び液晶表示装置 |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
WWE | Wipo information: entry into national phase |
Ref document number: 200980130652.4 Country of ref document: CN |
|
121 | Ep: the epo has been informed by wipo that ep was designated in this application |
Ref document number: 09834396 Country of ref document: EP Kind code of ref document: A1 |
|
DPE1 | Request for preliminary examination filed after expiration of 19th month from priority date (pct application filed from 20040101) | ||
WWE | Wipo information: entry into national phase |
Ref document number: 2010543835 Country of ref document: JP |
|
WWE | Wipo information: entry into national phase |
Ref document number: 13057297 Country of ref document: US |
|
NENP | Non-entry into the national phase |
Ref country code: DE |
|
122 | Ep: pct application non-entry in european phase |
Ref document number: 09834396 Country of ref document: EP Kind code of ref document: A1 |