JP5217791B2 - LIGHT EMITTING DEVICE AND ELECTRONIC DEVICE - Google Patents

Description

  The present invention relates to a light emitting device and an electronic device that emit light by electroluminescence.

  An organic light emitting diode (OLED), that is, an organic EL (Electro Luminescent) element, has attracted attention as a thin and light-emitting source, and an image display device including a large number of organic EL elements has been developed. The organic EL element has a structure in which at least one organic thin film formed of an organic material is sandwiched between a pixel electrode and a counter electrode.

  In the field of organic EL elements, a technique is known that uses amplifying interference, that is, resonance, to intensify light of a specific wavelength among emitted light (for example, Patent Document 1). With this technology, the color purity of the emitted color can be increased, and the efficiency of the emitted light with respect to the emitted light can be increased.

  The organic EL element has a problem that the quality of the display image is deteriorated due to reflection of external light on the display surface. In order to solve this, for example, it has been proposed to arrange a circularly polarizing plate on the display surface side. However, since the circularly polarizing plate attenuates light generated in the light emitting layer to half or less, the luminance is lowered.

  In addition, a method for reducing external light reflection by overlaying a color filter on an organic EL element has been proposed. This method is a method in which light having a wavelength other than the target wavelength to be transmitted is absorbed by the color filter. However, in the method using only the color filter, the reflection of light of a color different from the light emitted from the organic EL element is reduced, but the reflectance of the light of the same color or similar color as the light emitted from the organic EL element is reduced. Not so much reduced.

  Further, in Patent Document 2, adjustment is made so that the phase of the reflected light of the external light at the semi-transmissive reflective electrode of the organic light emitting element and the phase of the reflected light of the external light at the reflective electrode are reversed. Techniques to do this are disclosed.

WO 01/39554 pamphlet Japanese Patent No. 3944906

  As described in Patent Document 2, when the phase of the reflected light on one surface and the phase of the reflected light on the other surface are reversed, the reflected light may be reduced by attenuating interference. However, under this condition, there is a limit to increasing the efficiency of light emitted from the light emission of the organic light emitting device. In Patent Document 2, an organic light emitting device includes a transflective electrode and a reflective electrode, and light reciprocates between these electrodes, and has a resonator structure that resonates light. Although it is described, even if the light reciprocates between the electrodes, if the optical factor such as the optical distance is inappropriate, the light does not resonate and the utilization efficiency of the light cannot be improved.

  Accordingly, the present invention has been made to solve at least a part of the above-described problems, and can be realized as the following forms or application examples.

  In order to solve the above-described problems, a light-emitting device according to the present invention includes a first electrode layer, a second electrode layer, and a light-emitting functional layer disposed between the first electrode and the second electrode. A light emitting device having a light emitting element, a reflective layer that reflects light emitted from the light emitting functional layer toward the light emitting functional layer, and a light emitting function that is disposed on the opposite side of the reflective layer across the light emitting functional layer. A semi-transparent semi-reflective layer that reflects part of the light emitted from the layer toward the light-emitting functional layer and transmits the other part, and the semi-transparent semi-reflective layer has a refractive index of 1 or more It is.

According to the present invention, it is possible to suppress adverse effects such as deterioration in image quality due to reflection of external light incident on the light emitting device. This is due to the following circumstances.
The light-emitting device according to the present invention includes a resonator structure including a light-emitting element, a reflective layer, and a translucent semi-reflective layer. Since the translucent semi-reflective layer has a refractive index of 1 or more, the translucent semi-reflective layer The external light that is about to enter is refracted in the layer under a condition farther from the total reflection condition. On the other hand, assuming that the refractive index is less than 1, external light is refracted in the layer under conditions closer to the total reflection condition.
Comparing these two cases, the absolute amount of external light reflection itself is considered to be relatively smaller in the former than in the latter. Therefore, according to the present invention, an effect of reducing external light reflection can be obtained.

The light emitting device of the present invention further includes a color filter that is disposed on the opposite side of the light emitting functional layer with the semitransparent reflective layer interposed therebetween, and that transmits light transmitted through the semitransparent semireflective layer, from the reflective layer, the optical distance to an interface that does not face the reflective layer in the translucent semi-reflective layer may be configured to be determined based on the optical distance d ₂ which is calculated by the equation (1).
d ₂ = (p + 1/2) · λ / 2− (φ ₁ −φ ₂ ) · λ / 4π Formula (1)
Here, λ is a wavelength corresponding to the transmittance peak of the color filter, and φ ₁ is a wavelength λ light traveling from the side opposite to the light emitting functional layer to the translucent semi-reflective layer. the light emitting functional layer of transparent semi-reflective layer is a phase change when reflected at the interface on the side opposite, phi _2, the light of wavelength λ traveling to the reflective layer from the light-emitting functional layer side, the reflective layer And p is a positive integer.
According to this aspect, since the resonator structure is configured based on the optical distance for causing the attenuating interference, the above-described effect is more effectively achieved. A more specific configuration or structure that satisfies this requirement will be described in the embodiment.

The light emitting device of the present invention further includes a color filter disposed on the opposite side of the light emitting functional layer with the semitransparent reflective layer interposed therebetween, and transmitting the light transmitted through the semitransparent semireflective layer. semi-reflective layer has a predetermined physical thickness t _z, and, from the reflective layer, the optical distance to the interface which faces the reflective layer in the translucent semi-reflective layer is calculated by the equation (2) The optical distance d ₁ may be determined based on the optical distance d ₁ .
d ₁ = (p + 1/2) · λ / 2− (φ ₁ −φ ₂ ) · λ / 4π− _nz · t _z Formula (2)
Here, λ is a wavelength corresponding to the transmittance peak of the color filter, and φ ₁ is a wavelength λ light traveling from the side opposite to the light emitting functional layer to the translucent semi-reflective layer. the light emitting functional layer of transparent semi-reflective layer is a phase change when reflected at the interface on the side opposite, phi _2, the light of wavelength λ traveling to the reflective layer from the light-emitting functional layer side, the reflective layer , P is a positive integer, and _nz is the refractive index with respect to the wavelength λ of the translucent semi-reflective layer.
According to this aspect, since the resonator structure is configured based on the optical distance for causing the attenuating interference, the above-described effect is more effectively achieved. A more specific configuration or structure that satisfies this requirement will be described in the embodiment.
Incidentally, physical changes in the thickness t _z of translucent semi-reflective layer (adjustment of the various parameters used on the manufacturing process, or by their error and the like.) Usually results in a change in the refractive index. Therefore, it is preferred that, through adjusting the physical thickness t _z actively, the adjustment is made with a refractive index according to the refractive index, such as 1 or more, provided that is satisfied.

In the light emitting device of the present invention, the translucent transflective layer includes an alloy composed of at least two kinds of unit elements, a change in composition ratio of one type of unit elements, and the translucent transflective When the refractive index changes according to the change in the physical thickness of the layer, the alloy composition of the translucent semi-reflective layer depends on the physical thickness or the semi-transparent semi-reflective layer. The physical thickness may be determined according to the alloy composition.
According to this aspect, first, the refractive index of the translucent semi-reflective layer can be suitably adjusted through the adjustment of the physical thickness and the alloy composition ratio.
Moreover, according to this aspect, the design freedom regarding the material design of a translucent semi-reflective layer is raised. For example, when the composition ratio of the one kind of unit element increases, the refractive index decreases, and when the physical thickness increases, the refractive index increases. If the thickness is made relatively large, a material design such as increasing the composition ratio of the one kind of unit element becomes possible. Conversely, the physical thickness can be determined after the alloy composition has been determined in advance.
Here, in general, along with changes in the alloy composition ratio, optical properties such as transparency, mechanical, mechanical and physical properties such as strength and sensitivity to temperature changes (thermal expansion coefficient, etc.), various chemistry Typically, chemical properties such as resistance to substances etc. can also change. Therefore, it is preferable to determine the alloy composition ratio to be used in an actual apparatus after considering various circumstances.
In view of such circumstances, for example, as described above, the present aspect that the refractive index can be adjusted by adjusting the thickness even after the preferable alloy composition ratio is initially determined is extremely advantageous. It is. This is because it is possible to provide a translucent semi-reflective layer that satisfies various requirements from a general viewpoint.

In the light emitting device of the present invention, the translucent semi-reflective layer may include MgAg.
According to this aspect, the translucent semi-reflective layer preferably satisfies that “the refractive index is 1 or more”. In addition, when using this MgAg as a material which comprises a translucent semi-reflective layer, it is preferable that the film thickness shall be 12.5 nm or more, and the composition ratio of MgAg made Mg 10 In this case, the Ag ratio is preferably 10 or less. For the limiting significance, refer to the description in the later embodiments.

Moreover, in order to solve the said subject, the electronic device of this invention is equipped with the various light-emitting devices mentioned above.
According to the present invention, since the various light-emitting devices described above are provided, the effect of reducing external light reflection is effectively enjoyed. Therefore, it is possible to display a higher quality image.

  Embodiments according to the present invention will be described below with reference to the drawings. In the drawings, the ratio of dimensions of each part is appropriately changed from the actual one.

<Cross-sectional structure of organic EL device>
FIG. 1 is a cross-sectional view schematically showing an organic EL device 1 as a light emitting device according to an embodiment of the present invention. The organic EL device 1 includes a light emitting panel 3 and a color filter panel 30.

  The light emitting panel 3 includes a light emitting element 2 (2R, 2G, 2B) as a plurality of pixels as illustrated. The organic EL device 1 of this embodiment is used as a full-color image display device. The light emitting element 2R is a light emitting element whose emitted light color is red, the light emitting element 2G is a light emitting element whose emitted light color is green, and the light emitting element 2B is a light emitting element whose emitted light color is blue. . In FIG. 1, only three light emitting elements 2 are shown, but actually, a larger number of light emitting elements than those shown are provided. Hereinafter, the subscripts R, G, and B of the constituent elements correspond to the light emitting elements 2R, 2G, and 2B.

  The illustrated light emitting panel 3 is a top emission type. The light emitting panel 3 includes a substrate 10. The substrate 10 may be formed of a transparent material such as glass, or may be formed of an opaque material such as ceramic or metal.

  A reflective layer 12 having a uniform thickness is formed at least on the substrate 10 so as to overlap the light emitting element 2. The reflective layer 12 is formed of a material having high reflectance such as aluminum or silver, for example, and reflects light traveling from the light emitting element 2 (including light emitted from the light emitting element 2) upward in FIG. To do.

  An insulating transparent layer 14 is formed on the substrate 10 so as to cover the reflective layer 12. The insulator transparent layer 14 is made of a material having high translucency, such as an insulator such as SiN. Although not shown, in the insulator transparent layer 14, TFTs (thin film transistors) and wirings for supplying power to the respective light emitting elements 2 are embedded. The thickness of the insulating transparent layer 14 on the reflective layer 12 is uniform regardless of the emission color of the overlapping light emitting elements 2.

  On the insulating transparent layer 14, a partition wall 16 is formed as a separator for separating the light emitting element 2. The partition wall 16 is formed of an insulating resin material such as acrylic, epoxy, or polyimide.

Each light emitting element 2 includes a first electrode layer 18, a second electrode layer 22 as a translucent semi-reflective layer, and a light emitting function disposed between the first electrode layer 18 and the second electrode layer 22. Layer 20.
In the present embodiment, the first electrode layer 18 (18R, 18G, 18B) is a pixel electrode provided in each pixel (light emitting element 2), for example, an anode. The first electrode layer 18 is made of a transparent material such as ITO (Indium Tin Oxide) or ZnO ₂ . The thickness of the first electrode layer 18 varies depending on the emission color. That is, the first electrode layers 18R, 18G, and 18B have different thicknesses.

  In the present embodiment, the light emitting functional layer 20 is formed in common for the plurality of light emitting elements 2 and has a uniform thickness regardless of the light emission color of the light emitting elements 2. The light emitting functional layer 20 has at least an organic light emitting layer. The organic light emitting layer emits white light when a current flows. That is, it emits light having red, green and blue light components. The organic light emitting layer may be a single layer or may be composed of a plurality of layers (for example, a blue light emitting layer that emits mainly blue light when current flows and a yellow light emitting layer that emits light including red and green when current flows). It may be.

  Although not shown, the light emitting functional layer 20 has layers such as a hole transport layer, a hole injection layer, an electron block layer, a hole block layer, an electron transport layer, and an electron injection layer in addition to the organic light emitting layer. May be. When the light emitting functional layer 20 is composed of a plurality of layers, each layer also has a uniform thickness regardless of the light emission color of the light emitting element 2.

The second electrode layer 22 as a translucent semi-reflective layer is made of a translucent semi-reflective alloy or metal material such as MgAl, MgCu, MgAu, MgAg, for example. In the present embodiment, the second electrode layer 22 is a common electrode provided in common to a plurality of pixels (light emitting elements), for example, a cathode. The second electrode layer 22 has a uniform thickness regardless of the emission color of the light emitting element 2. The second electrode layer 22 transmits a part of the light (including the light from the light emitting functional layer 20) traveling from the light emitting functional layer 20 upward in the figure, and the other part of these lights in the figure. Reflected downward, that is, toward the first electrode layer 18.
Among the above, the second electrode layer 22 is preferably made of a material having a refractive index of 1 or more such as MgAg. However, this point will be more specifically described in the following description of the function and effect. This will be explained anew, with explanations on various data.

  Inside the opening (pixel opening) formed between the plurality of partition walls 16, the light emitting functional layer 20 is in contact with the first electrode layer 18. In a certain light emitting element 2, the first electrode layer 18 and the first electrode layer 18 are in contact with each other. When a current is passed between the two electrode layers 22, holes are supplied from the first electrode layer 18 to the light emitting functional layer 20 of the light emitting element 2, electrons are supplied from the second electrode layer 22, and The holes and electrons combine to emit light. Accordingly, the light emitting region of the light emitting element 2 is roughly defined by the pixel openings formed between the partition walls 16. That is, the pixel opening of the partition wall 16 separates the light emitting element 2.

  Although only shown in FIG. 2, an extremely thin passivation layer 27 is formed on the upper surface of the second electrode layer 22. The passivation layer 27 is made of a transparent inorganic material such as SiON, for example, and prevents the light emitting functional layer 20 of the light emitting element 2 from being deteriorated by moisture or oxygen. In this way, the light emitting panel 3 is formed.

The light emitting functional layer 20 emits white light, but the light reciprocates between the reflective layer 12 and the second electrode layer 22, whereby each light emitting element 2 emits light in which light of a specific wavelength is amplified. . That is, the light emitting element 2R amplifies and emits light with a red wavelength, the light emitting element 2G amplifies and emits light with a green wavelength, and the light emitting element 2B amplifies and emits light with a blue wavelength. . For this purpose, the light emitting elements 2R, 2G, and 2B have different optical distances d ₁ (d _1R , d _1G , d _1B ) between the reflective layer 12 and the second electrode layer 22. The optical distance d ₁ (d _1R , d _1G , d _1B ) and the optical distance d ₂ (d _2R , d _2G , d _2B ) in the figure indicate the optical distance, and the actual distance is It is not shown.

A color filter panel 30 is joined to the light emitting panel 3 by a transparent adhesive 28. The color filter panel 30 includes a substrate 32 made of a transparent material such as glass, a black matrix 34 formed on the substrate 32, and a color filter 36 (36R, 36) disposed in an opening formed in the black matrix 34. 36G, 36B).
The adhesive 28 is disposed between the color filter 36 of the color filter panel 30 and the passivation layer 27 (see FIG. 2) of the light emitting panel 3, and the substrate 32 and the color filter 36 in the color filter panel 30 are attached to each layer of the light emitting panel 3. It supports in parallel with respect to.

Each of the color filters 36 is disposed at a position overlapping the light emitting element 2, particularly the first electrode layer 18. The color filter 36 is disposed on the opposite side of the light emitting functional layer 20 with the translucent semi-reflective second electrode layer 22 interposed therebetween, and transmits light transmitted through the second electrode layer 22 of the overlapping light emitting element 2. .
More specific description will be given below.

  The color filter 36R overlaps the light emitting element 2R, and one color filter 36R and one light emitting element 2R constitute one set. The color filter 36R has a function of transmitting red light, and the peak of the transmittance is at a wavelength of 610 nm. The color filter 36R transmits red light out of the amplified red light transmitted through the second electrode layer 22 of the overlapping light emitting element 2R, and increases the purity of red. The color filter 36R absorbs most of green and blue light.

  The color filter 36G overlaps the light emitting element 2G, and one color filter 36G and one light emitting element 2G constitute one set. The color filter 36G has a function of transmitting green light, and the peak of the transmittance is at a wavelength of 550 nm. The color filter 36G transmits green light out of the amplified green light transmitted through the second electrode layer 22 of the overlapping light emitting element 2G, and increases the purity of green. The color filter 36G absorbs most of red and blue light.

  The color filter 36B overlaps the light emitting element 2B, and one color filter 36B and one light emitting element 2B constitute one set. The color filter 36B has a function of transmitting blue light, and the peak of the transmittance is at a wavelength of 470 nm. The color filter 36B overlaps the light emitting element 2B, and transmits blue light out of the amplified blue light transmitted through the second electrode layer 22 of the light emitting element 2B, thereby increasing the purity of blue. The color filter 36B absorbs most of red and green light.

<Light reflection and transmission model>
FIG. 2 is a schematic diagram schematically showing the locus of light when external light arrives toward the light emitting element 2 of the light emitting panel 3 through the color filter 36. The external light transmitted through the color filter 36 passes through the transparent adhesive 28, further passes through the passivation layer 27, and reaches the translucent semi-reflective second electrode layer 22. A part of the external light is reflected at the interface between the passivation layer 27 and the second electrode layer 22 (the interface on the opposite side of the second electrode layer 22 from the light emitting functional layer 20). The phase change at the time of reflection is φ ₁ .

The other part of the external light is transmitted through the translucent and semi-reflective second electrode layer 22, and further transmitted through the light emitting functional layer 20, the first electrode layer 18, and the insulator transparent layer 14. Reflected by the surface of the 12 light emitting functional layers 20 side. Let the phase change during this reflection be φ ₂ .
The reflected light from the reflective layer 12 is transmitted through the insulator transparent layer 14, the first electrode layer 18, and the light emitting functional layer 20, and part of the light is transmitted through the second electrode layer 22 that is translucent and semi-reflective. It progresses from the light emitting element 2 to the adhesive 28 and interferes with the reflected light at the interface between the passivation layer 27 and the second electrode layer 22 described above. In FIG. 2, the optical path change due to light refraction at each interface is not shown, and the optical path is shown by a straight line.

In order to reduce the reflected light at the separate interface as described above by attenuating interference, it is preferable to satisfy Equation (3).
2 · d ₂ = (p + _1/2 ) · λ− (φ ₁ −φ ₂ ) · λ / 2π Formula (3)
Here, d ₂ is an optical distance (nm) between the interface of the reflective layer 12 on the light emitting functional layer 20 side and the interface of the second electrode layer 22 opposite to the light emitting functional layer 20. The optical distance d ₂ is the sum of products of refractive index and thickness of the insulating transparent layer 14, the second electrode layer 22, and the layers between them.

  “Wavelength λ” in Expression (3) is the wavelength (nm) of the light component to be attenuated. Since the external light in question is light that passes through the color filter 36 and travels toward the light emitting panel 3, it is light in the transmission wavelength region of the color filter 36. Therefore, it is appropriate that the “wavelength λ” in Equation (3) is a wavelength corresponding to the transmittance peak of the color filter.

Φ _{1 in the} formula (3) is the light emitting functional layer 20 of the second electrode layer 22 in which the light of wavelength λ traveling from the opposite side to the light emitting functional layer 20 to the second electrode layer 22 is translucent and semi-reflective. Is a phase change (rad) when the light is reflected at the interface on the opposite side, and φ ₂ is a phase when the light of wavelength λ traveling from the light emitting functional layer 20 side to the reflective layer 12 is reflected by the reflective layer 12. Rad. P is a positive integer, preferably 1.

Such an expression (3) can be written down as an individual expression for each of the red, green, and blue light emitting elements 2R, 2G, and 2B. That is,
d _2R = (p + 1/2) · λ _R / 2− (φ _1R −φ _2R ) · λ _R / 4π Formula (4)
d _2G = (p + 1/2) · λ _G / 2− (φ _1G −φ _2G ) · λ _G / 4π Formula (5)
d _2B = (p + 1/2) · λ _B / 2− (φ _1B −φ _2B ) · λ _B / 4π Formula (6)
Here, d _2R is the optical distance d _{2 with} respect to the light emitting element 2R, λ _R is the wavelength 610 nm corresponding to the peak of the transmittance of the color filter 36R, and φ _1R is the phase change φ ₁ , φ _2R at the wavelength λ _R. Is the phase change φ ₂ at the wavelength λ _R.
D _2G is the optical distance d ₂ of the light emitting element 2G, λ _G is the wavelength 550 nm corresponding to the peak of transmittance of the color filter 36G, φ _1G is the phase change φ ₁ , φ _2G at the wavelength λ _G is The phase change φ ₂ at the wavelength λ _G , d _2B is the optical distance d ₂ for the light emitting element 2B, λ _B is the wavelength 470 nm corresponding to the peak of the transmittance of the color filter 36B, and φ _1B is the wavelength λ _B The phase changes φ ₁ and φ _{2B at} are the phase changes φ ₂ at the wavelength λ _B.

The optical distance d ₁ (nm) between the reflective layer 12 and the second electrode layer 22 is opposite to the light emitting functional layer 20 side interface of the reflective layer 12 and the light emitting functional layer 20 of the second electrode layer 22. There is a relationship shown in the equation (7) between the optical distance d ₂ with the side interface.
d ₁ = d ₂ −n _z · t _z
Therefore, d ₁ = (p + 1/2) · λ / 2− (φ ₁ −φ ₂ ) · λ / 4π− _nz · t _z (7)
Here, n _z is the refractive index of the second electrode layer 22 with respect to light of wavelength λ, and t _z is the thickness of the second electrode layer 22.

Therefore, for each light emitting element 2R, 2G, 2B, equation (7) can be rewritten as equations (8) to (10).
d _1R = (p + 1/2) · λ _R / 2− (φ _1R −φ _2R ) · λ _R / 4π−n _zR · t _z (8)
_{d 1G = (p + 1/} 2) · λ G / 2- (φ 1G -φ 2G) · λ G / 4π-n zG · t z ... (9)
d _1B = (p + 1/2) · λ _B / 2− (φ _1B −φ _2B ) · λ _B / 4π−n _zB · t _z Formula (10)
Here, d _1R, the optical distance d _1, n _zR of light-emitting element 2R is a refractive index n _z of the second electrode layer 22 to an optical wavelength lambda _R.
Further, d _1G, the optical distance d _1, n _zG the light-emitting element 2G is the refractive index n _z of the second electrode layer 22 to an optical wavelength lambda _G, d _1B, the optical of a light-emitting element 2B The distances d ₁ and _nzB are the refractive indices _nz of the second electrode layer 22 with respect to light of wavelength λ _B.
As described above, the conditions suitable for reducing the reflected light at the separate interface by attenuating interference have been described.

<Operation effect of organic EL device>
Hereinafter, operational effects of the organic EL device having the above-described configuration will be described with reference to FIGS. 3 to 9 in addition to FIGS. 1 and 2 already referred to.
These FIG. 3 thru | or FIG. 9 has shown the result of having performed the optical simulation based on the organic electroluminescent apparatus which has the structure demonstrated above. This simulation result is obtained using the product name “Opt Designer” which is an optical simulation program produced by Toyota Central Research Laboratory. This also applies to FIGS. 10 to 14 to be referred to later.

<Film thickness and refractive index>
First, as a premise for explaining the function and effect of the organic EL device of the present embodiment, the relationship between the thickness and the refractive index of the second electrode layer 22 will be described.
In the upper part of FIG. 3, a graph for this relationship is shown.
As shown in this figure, it is first confirmed that the refractive index increases almost proportionally as the wavelength increases regardless of the difference in thickness of the second electrode layer 22.
In addition, this figure confirms that the refractive index increases as the thickness of the second electrode layer 22 increases. That is, in FIG. 3, the refractive indexes in the case where the film thicknesses are T1 = 11 nm, T2 = 12.5 nm, and T3 = 20 nm are shown, but in the case of the film thickness T1, the wavelength reaches about the middle of 600 nm. Refractive index does not reach unity. On the other hand, in the case of the film thickness T2 and the film thickness T3, the refractive index is 1 or more over the entire wavelength region. In particular, from this figure, it can be seen that the critical value for the refractive index to be 1 or more in the entire wavelength region is the film thickness T2.

3 is obtained through the process of obtaining the complex refractive index n _c = n−jk, and the “refractive index” on the vertical axis in FIG. 3 indicates the real part n. Means value. An extinction coefficient k is also determined, but is not shown in FIG. In the upper left part of FIG. 3, the expression “real part of refractive index” is used with the intention of expressing this. The above matters also apply to FIGS. 10 and 11 to be referred to later.
Further, the upper result of FIG. 3 shows that the second electrode layer 22 is made of an alloy containing Mg and Ag, and the former is made of an alloy having a weight ratio of 1 with respect to 10. If you are based. Such a situation is also assumed in FIGS. 4 to 9 referred later.

  FIG. 3 shows the relationship between the change in each film thickness T1, T2, T3 and the refractive index, and the relationship between the change in each film thickness T1, T2, T3 and the external light reflectance. Is shown in This figure relates to the external light reflectance for green light. Further, the reflectance is assumed that the equal energy white light passes through the color filter 36 and reaches the light emitting panel 3, and the intensity of the light resulting from the reflected light passing through the color filter 36 and the original equal energy white light. It is determined based on the ratio of light intensity. This situation also applies to FIGS. 6 to 9 and FIGS. 12 to 14 referred to later.

This result is based on the results obtained by the above-described equations (5) and (9). That is, the optical distance d _2G for causing the attenuating interference of the reflected light is obtained from the former equation (5), and from the latter equation (9), the optical distance d _2G for causing the attenuating interference of the reflected light is also obtained. Although the optical distance d _1G is required for the latter optical distance d _1G, the thickness t _z of the second electrode layer 22 in the formula (9), each of the film thickness T1, T2, T3 Assigned. The result of FIG. 6 is that the cross-sectional structure related to the light emitting element 2R of the organic EL device is based on or substantially satisfied the three types of optical distance d _1G and optical distance d _2G thus obtained. It is calculated | required by setting on simulation.
As values to be substituted into the equations (5) and (9) for obtaining the optical distance d _1G and the optical distance d _2G described above, for example, values as shown in FIG. In this case, since green light is a problem, the value in the “light emitting element 2G” column in FIG. Using such values, when p = 1, n _zG = 1.24, and t _z = 12.5 nm, the optical distance d _1G and the optical distance d _2G are d _1G = About 406.2 nm and d _2G = about 422.0 nm.
In the case of executing the above simulation, the thickness of the insulating transparent layer 14 and the thickness of the light emitting functional layer 20 are common to the light emitting elements 2R, 2G, and 2B, and the thickness of the first electrode layer 18 is the light emitting element. The condition is that it differs depending on 2R, 2G, and 2B.
Further, in the actual simulation, the material, thickness and refractive index of each layer are set as shown in FIG. Incidentally, according to the numerical values set forth herein, 'when calculating the value, d _1G' optical distance d _1G is an optical distance d _1G corresponding value becomes = about 426.3Nm. The difference between the optical distance d _1G ′ and the optical distance d _1G is that in the latter calculation formulas (5) and (9) This is because reflection by the interface is not considered. As described above, the optical distance d _1G ′ and the optical distance d _1G do not always coincide with each other, but the optical distance d _1G ′ is still based on the optical distance d _1G .
In FIGS. 4 and 5, similar numerical values relating to blue light and red light shown in FIGS. 6 and 7 described later are also shown.

  As shown in the lower part of FIG. 3, it can be seen that the reflectance decreases or increases with a certain period with respect to the wavelength, but in any of the film thicknesses T1, T2 and T3, green light is emitted. It can be seen that the reflectance near the peak wavelength of 550 nm is reduced. However, a difference in reflectance reduction based on the difference between these film thicknesses T1, T2, and T3 is also confirmed. That is, the result of the film thickness T1 has the weakest effect of reducing the reflectance at the peak wavelength of 550 nm. Subsequently, the film thickness T3 is improved, and the best result is obtained with the film thickness T2. However, the results of the film thickness T2 and the film thickness T3 are in a range that can be said to be almost the same.

  As a result, it can be understood that there is a certain correlation between the effect of reducing the reflectance and the refractive index described with reference to the upper part of FIG. That is, it can be said that a more effective reflectance reduction effect can be obtained when the refractive index is 1 or more.

Such a correlation between the refractive index and the reflectance reduction effect is also confirmed from the following.
That is, first, attention is paid to the minimum value in each of the curves showing the reflectivity changing according to the wavelength shown in the lower part of FIG. As shown in the figure, these minimum values are m1, m2, and m3 for each of the curves related to the film thicknesses T1, T2, and T3.

Next, it is confirmed what the refractive index of the second electrode layer 22 is at wavelengths corresponding to these minimum values m1, m2, and m3. In FIG. 3, this can be seen visually. For example, a line segment R1 having a point of the minimum value m1 as one end point extends upward in the figure and intersects the wavelength-refractive index curve shown in the upper part of FIG. What should be noted here is the wavelength-refractive index curve relating to the film thickness T1, and it can be seen that the refractive index corresponding to the minimum value m1 is 1 or less.
The same applies to the remaining line segment R2 and line segment R3. However, when the upper end points in FIG. 3 of the line segment R2 and the line segment R3 are seen, it can be seen that the refractive index is 1 or more.

From the above, the following can be inferred.
That is, the above formulas (5) and (9) are formulas for _obtaining the optical distance d _1G and the optical distance d _2G for causing the attenuating interference as described above, but the wavelength λ _G It is not impossible to calculate the optical distance d _1G and the optical distance d _{2G at} which the reflectance should be minimized at wavelengths in the vicinity thereof. Since the simulation is performed under conditions that substantially coincide with the optical distance d _1G and the optical distance d _2G , the resulting minimum values m1, m2, and m3 in the lower part of FIG. _Can be said to reflect the optical distance d _1G and the optical distance d _2G that should be minimized. In particular, the optical distance d _1G changes according to the refractive index n _zG (and physical thickness t _zG ) of the second electrode layer 22 as shown in the above-described equation (9).
In summary, the change in the refractive index n _zG affects the optical distance d _1G , which further affects the reflectance reduction effect, specifically the minimum values m1, m2, and m3. You can see a series of relationships.

Here, looking again at the minimum values m1, m2, and m3, it can be seen that there is a significant difference W between the minimum value m1, the minimum value m2, and the minimum value m3. Between the two, as described above, there is a relationship that the former has a refractive index _nzG lower than 1 and the latter becomes 1 or more. If this is the case, it may be considered that there is some correlation between whether the value of the refractive index n _zG is less than 1 or greater than 1 and whether or not the remarkable difference W occurs. Is possible.

Although it can be read from FIG. 3 that there is a correlation as described above, the cause is not necessarily clear. However, the case where the refractive index _nzG is _less than 1 generally means that the refraction angle increases with respect to the incident angle, so that the closer to that degree, the closer to the total reflection condition. . If this is the case, it is estimated that the amount of reflected light will generally increase accordingly. Then, even if the optical distance d _1G and the optical distance d _2G causing the attenuating interference are obtained by the above equations (5) and (9), the refractive index _nzG is less than 1. It is considered that the effect of the interference is weakened relatively or substantially as compared with the case where the refractive index _nzG is 1 or more.

In any case, as described above, when the refractive index _nzG is 1 or more, the reflectance reduction effect is better obtained.

  6 and 7 are diagrams having the same concept as the lower part of FIG. 3 and show the relationship between the changes in the film thicknesses T1, T2 and T3 and the external light reflectance. The former is blue light, and the latter Is for red light. These figures are similar to those described above with respect to FIG. 6 in terms of Equations (6) and (10), and with respect to FIG. 7 as Equations (4) and (8) described above for green light. Relevant in significance.

Among these drawings, FIG. 6 (blue light) is more effective as the case of FIG. 3 or more clearly, as the film thickness of the second electrode layer 22 increases, the reflectance reduction effect becomes better. It can be said that it has been achieved. In FIG. 7 (red light), it can be said that there is not much difference between the film thicknesses T1, T2, and T3 in the region where the wavelength is small, but the same tendency as in FIG. Can be read. That is, as can be seen from the region from the wavelength of 600 nm to the middle of the wavelength (see the dashed box in FIG. 7), in the case of the film thickness T1, that is, when the refractive index _nzR is _less than 1, the film thickness T2 and There is a significant difference between the case of the film thickness T3, that is, the case where the refractive index _nzR is 1 or more, and the former has a higher reflectance than the latter. It is. Such a phenomenon can be seen to some extent at the wavelength of 470 nm and its vicinity in the case of FIG.

FIG. 8 shows the simulation results of FIG. 6 and FIG. 7 below FIG. 3 when the film thickness of the second electrode layer 22 is 12.5 nm (that is, FIG. 3, FIG. 6 and FIG. 7). The film thickness is limited to the film thickness T2). The reason why the film thickness T2 = 12.5 nm is selected is that, as described above, the film thickness T2 is a critical value for the refractive index to be 1 or more in the entire wavelength region (see FIG. 3). ).
As shown in this figure, the curve Gref has an extremely low reflectance value near the peak wavelength of 550 nm, the curve Bref has an extremely low reflectance value near the peak wavelength of 470 nm, and the curve Rref has an extremely low reflectance at the peak wavelength of 610 nm. Takes a value.

And since the reflectance regarding all the colors becomes such a result, as shown in FIG. 9, the reflectance as the visibility characteristic is marked with an extremely excellent result of 10% or less for any color. . In FIG. 9, the reduction of the reflectance in the vicinity of the peak wavelength of each color is a result of reflecting the results of FIG. 6 and FIG. On the other hand, the reason why the reflectance is reduced in other wavelength regions is a reflection of the absorption effect of the color filter 36. For example, the curve Gsf in FIG. 9 has a low reflectance value due to light absorption by the color filter 36G in a wavelength region other than the vicinity of the peak wavelength of 550 nm (the other curves Bsf and Rsf are also shown). The same).
In the above, “reflectance as the visibility characteristic” means the reflectance when a large number of light emitting elements 2 are viewed comprehensively through the color filter 36. Specifically, it is obtained as a result of integrating the graph of FIG.

As described above, in the organic EL device of this embodiment, when the refractive index of the second electrode layer 22 is 1 or more, a better reflectance reduction effect can be obtained.
As is clear from the above description and FIG. 3 and the like, the refractive index of the second electrode layer 22 in the visible light region (400 nm to 800 nm) at a wavelength of 400 nm is desirably 1 or more. On the other hand, the substantial upper limit value of the refractive index is preferably defined by the refractive index at a wavelength of 800 nm, and the upper limit value of the refractive index of the second electrode layer 22 may be 3 or less. The upper limit may be 2.5 or less.

<Alloy composition and refractive index>
Next, the influence of the composition of the second electrode layer 22 on the refractive index of the second electrode layer 22 will be described.
FIG. 10 shows the composition ratio between Mg and Ag, which are the composition components, while the film thickness of the second electrode layer 22 is fixed to 12.5 nm (= film thickness T2) as in FIGS. It is a graph which shows what a refractive index becomes when it is changed.
As shown in FIG. 10, when the composition ratio of Mg and Ag is 10: 1 (see reference sign “C1” in the figure), the refractive index gradually decreases as the Ag ratio increases. Is confirmed. In FIG. 10, the case of Mg: Ag = 10: 3 is shown as “C2”, and the case of 10: 5 is also shown as “C3”. Further, the case where Ag is not included, that is, the case of Mg alone is indicated as “C0”.

Next, FIG. 11 shows how the refractive index changes when the physical thickness of the second electrode layer 22 is increased based on FIG. Specifically, in FIG. 11, the thickness of the second electrode layer 22 is 20 nm, which is larger than 12.5 nm in the case of FIG.
As can be seen from FIG. 11, the refractive index increases as the film thickness increases. For example, the curve labeled “C1” in FIG. 11 is compared with the curve labeled “C1” in FIG. 10 (both are curves when Mg: Ag = 10: 1). As can be seen, it can be seen that the larger the film thickness, the higher the refractive index value in the entire wavelength region, as if the entire film is raised.
On the other hand, FIG. 11 also shows that the refractive index decreases as the composition ratio of Ag in MgAg increases. This tendency is the same as the tendency described with reference to FIG. In FIG. 11, the case of Mg: Ag = 10: 10 is indicated as “C4”. The meanings of the symbols “C0” and “C3” are the same as in the case of FIG.

10 and 11, the refractive index decreases as the Ag composition ratio in the MgAg alloy increases. On the other hand, the refractive index increases as the film thickness of the second electrode layer 22 increases. You can see that
Here, FIG. 10 and FIG. 11 will be reviewed again in consideration of the above-described viewpoint that the refractive index is desirably 1 or more. Then, in the case of the curve labeled with “C3” in FIG. 10, there is a portion where the refractive index is 1 or less in a region with a small wavelength. However, even with the same composition ratio, it can be seen that the refractive index is 1 or more in the entire wavelength region in the case of the curve labeled “C3” in FIG. As described above, this is because the film thickness is 20 nm in the case of FIG. 11 and is larger than that of 12.5 nm in FIG.
In short, from these FIG. 10 and FIG. 11, if the film thickness of the second electrode layer 22 is increased, the “overall increase” regarding the refractive index as described above can be realized. It is possible to read a certain relationship that the ratio of Ag can be increased to a certain degree. Referring to FIG. 11, if the film thickness is 20 nm, the critical composition ratio is set to Mg: Ag = 10: 10, although the wavelength is in the vicinity of 400 nm and the refractive index is slightly less than “1”. It is considered possible.

FIG. 12 is a diagram having the same concept as in the lower part of FIG. 3 and FIGS. 6 and 7. However, in FIG. 12, the composition ratio of the second electrode layer 22 is changed as a parameter instead of the film thicknesses T1, T2, and T3 being changed as parameters in FIG. That is, FIG. 12 shows the relationship between the changes in the curves C1, C3, and C4 as the respective composition ratios described above and the external light reflectance.
In addition, this FIG. 12 is a result on the assumption of the following each premise. (I) The meanings of the curves C1, C3, and C4 as the respective composition ratios in FIG. 12 are the same as those in FIG. 11, (ii) the film thickness is 20 nm as in FIG. 11, (iii) FIG. Is a simulation of the reflectance for green light.

  As shown in FIG. 12, the reflectance decreases or increases with a certain period with respect to the wavelength, as in the lower part of FIG. In any of C4, it turns out that the reflectance of the peak wavelength 550nm vicinity regarding green light is reducing. However, the difference in the state of reflectance reduction based on the difference between the curves C1, C3, and C4 as the composition ratio is also confirmed. That is, the result of the curve C1 as the composition ratio has the weakest reflectance reduction effect at the peak wavelength of 550 nm. Subsequently, the curve C4 as the composition ratio is improved, and the best result is obtained with the curve C3 as the composition ratio. However, the results of the curve C3 as the composition ratio and the curve C4 as the composition ratio are in a range that can be said to be almost the same.

  This result suggests that the reflectance reduction effect can be more effectively enjoyed through the composition ratio change. This is because the curve labeled “C1” in FIG. 12 is substantially the same as the curve labeled “T3” in the lower part of FIG. That is, both reflect the reflectance when assuming the second electrode layer 22 having a film thickness of 20 nm and a composition ratio of Mg: Ag = 10: 1. Accordingly, the remaining curves C3 and C4 in FIG. 12 are improved compared to the curve “T2” indicating the film thickness T2 and the curve “T3” indicating the film thickness T3 shown in the lower part of FIG. Yes (note that the way the scale on the vertical axis swings differs between FIG. 12 and the lower part of FIG. 3).

  As a result, if the film thickness is sufficiently large, even if the composition ratio of Ag in MgAg is increased, the refractive index becomes 1 or more in the main wavelength region. It can be said that a reduction effect is obtained.

FIG. 13 shows the simulation results of FIG. 12 described above, and the simulation results similar to those of FIG. 12 regarding blue light and red light (not shown) (corresponding to the above-mentioned FIG. 6 and FIG. 7). This is shown only when the thickness of the layer 22 is 20 nm (that is, the curve C1 in FIG. 12). The reason why the film thickness is selected to be 20 nm is to compare FIG. 14 described later based on FIG. 13 with FIG. 9 described above (this point will be described later).
As shown in FIG. 13, the curve Gref has an extremely low reflectance value near the peak wavelength of 550 nm, the curve Bref has an extremely low reflectance value near the peak wavelength of 470 nm, and the curve Rref has an extremely low reflectance at the peak wavelength of 610 nm. Take a rate value.

  Then, since the reflectances for all colors have such a result, as shown in FIG. 14, the reflectance as the visibility characteristic is marked with an excellent result of about 5% or less for any color. The In FIG. 14, the reduction of the reflectance in the vicinity of the peak wavelength of each color is a result of reflecting the result of FIG. On the other hand, the reason why the reflectance is reduced in other wavelength regions is a reflection of the absorption effect of the color filter 36. For example, the curve Gsf in FIG. 14 has a low reflectance value due to light absorption by the color filter 36G in a wavelength region other than the vicinity of the peak wavelength of 550 nm (the other curves Bsf and Rsf are also shown). The same). Note that the meaning of “reflectance as a visibility characteristic” is the same as described above with reference to FIG.

As can be seen by comparing FIG. 14 with FIG. 9 described above, it can be seen that the reflectivity as the visibility characteristic is more improved in FIG. This can be regarded as a change that occurs as the refractive index increases (see the curve C1 in FIG. 10 and the curve C1 in FIG. 11 for comparison). Both FIG. 14 and FIG. 9 are the same when Mg: Ag = 10: 1. However, regarding the film thickness, FIG. 14 is different from 20 nm and FIG. 9 is different from 12.5 nm. Therefore, it can be said at least that the difference between the two is an effect based on the difference in film thickness.
Thus, in the organic EL device of the present embodiment, not only the refractive index of the second electrode layer 22 is 1 or more, but also a better reflectance reduction effect can be obtained by appropriately adjusting the alloy composition ratio. can get.

As mentioned above, although embodiment concerning this invention was described, the light-emitting device concerning this invention is not limited to the form mentioned above, Various deformation | transformation are possible.
(1) In the above-described embodiment, the transparent first electrode layer 18 is an anode, and the semitransparent semi-reflective second electrode layer 22 is a cathode. However, the first electrode layer 18 is a cathode and the second electrode layer 18 is a cathode. The electrode layer 22 may be an anode.
(2) In the embodiment described above, the first electrode layer 18 and the reflective layer 12 are separate layers, but the first electrode layer 18 may also be used as the reflective layer.

(3) Although the light emitting device according to the above-described embodiment is a top emission type, the light emitting device according to the present invention may be a bottom emission type. That is, the reflective layer may be disposed in a layer farther from the substrate than the light emitting functional layer, and the translucent reflective layer may be disposed in a layer closer to the substrate than the light emitting functional layer.
(4) Although the light emitting device according to the above-described embodiment is an organic EL device, the light emitting device according to the present invention may be an inorganic EL device.

(5) In the above embodiment, the light emitting functional layer 20 emits white light, but the present invention is not limited to such a form. For example, as shown in FIG. 15, the light emitting elements 2R, 2G, and 2B may be provided with dedicated light emitting functional layers 20R, 20G, and 20B, respectively. Each of the light emitting functional layers 20R, 20G, and 20B is disposed in the pixel opening of the partition wall 16. The light emitting functional layer 20R emits red light, the light emitting functional layer 20G emits green light, and the light emitting functional layer 20B emits blue light.
And also in this form, the thickness of the 1st electrode layer 18 differs according to light emitting element 2R, 2G, 2B. As in the above-described embodiment, this is the optical distance d ₂ calculated from the above-described equations (4) to (6), and the optical distance d calculated from the equations (8) to (10). _This is to try to satisfy ₁ .

(6) In the above-described embodiment, in order to satisfy the optical distance d ₁ and the optical distance d ₂ described above, the thickness of the first electrode layer 18 is adjusted by adjusting the thickness of the actual laminated structure. However, the present invention is not limited to such a form.
For example, as shown in FIG. 16, the thickness of the light emitting functional layers 20R, 20G, and 20B may be varied depending on the light emitting elements 2R, 2G, and 2B. Alternatively, as shown in FIG. 17, the thickness of the insulating transparent layer 14 may be varied depending on the light emitting elements 2R, 2G, and 2B.

<Application>
Next, an electronic apparatus to which the organic EL device according to the present invention is applied will be described. FIG. 18 is a perspective view illustrating a configuration of a mobile personal computer using the light emitting device according to the above-described embodiment as an image display device. The personal computer 2000 includes the organic EL device 1 as an image display device and a main body 2010. The main body 2010 is provided with a power switch 2001 and a keyboard 2002.
FIG. 19 shows a mobile phone to which the light emitting device according to the above embodiment is applied. A cellular phone 3000 includes a plurality of operation buttons 3001, scroll buttons 3002, and the organic EL device 1 as an image display device. By operating the scroll button 3002, the screen displayed on the organic EL device 1 is scrolled.
FIG. 20 shows an information portable terminal (PDA: Personal Digital Assistant) to which the light emitting device according to the embodiment is applied. The information portable terminal 4000 includes a plurality of operation buttons 4001, a power switch 4002, and the organic EL device 1 as an image display device. When the power switch 4002 is operated, various types of information such as an address book and a schedule book are displayed on the organic EL device 1.

  As electronic devices to which the organic EL device according to the present invention is applied, in addition to those shown in FIGS. 18 to 20, a digital still camera, a television, a video camera, a car navigation device, a pager, an electronic notebook, electronic paper, a calculator, Examples include a word processor, a workstation, a videophone, a POS terminal, a video player, and a device equipped with a touch panel.

Sectional drawing which shows the outline of the light-emitting device which concerns on embodiment of this invention. In the light emitting device of FIG. 1, the schematic diagram which shows simply the locus | trajectory of light when external light comes toward the light emitting element of a light emission panel through a color filter. The upper part is a graph showing the relationship between the refractive index of the electrode layer and the incident light wavelength when the film thickness of the second electrode layer shown in FIG. 1 is used as a parameter, and the lower part is a graph showing the second electrode. The graph which shows the simulation result of the reflectance regarding the green light in the light-emitting device of FIG. 1 when the film thickness of a layer is used as a parameter. The figure which shows an example of the value which should be substituted to Formula (4) thru | or Formula (6), Formula (8) thru | or Formula (10) demonstrated in a specification. The figure which shows an example of the set of the thickness of each layer shown in FIG. 1 which should be a premise of the reflectance calculation simulation shown in FIG.3, FIG.6, FIG.7. The graph which shows the simulation result of the reflectance regarding the blue light in the light-emitting device of FIG. 1 when the film thickness of a 2nd electrode layer is used as a parameter. The graph which shows the simulation result of the reflectance regarding the red light in the light-emitting device of FIG. 1 when the film thickness of a 2nd electrode layer is made into a parameter. A graph collectively showing a case where the film thickness of the second electrode layer is T2 = 12.5 nm among the simulation results in the lower part of FIG. 3 (green light), FIG. 6 (blue light), and FIG. 7 (red light). . The graph which shows the simulation result of the reflectance as a visibility characteristic calculated | required based on FIG. The graph which shows the relationship between the refractive index of a 2nd electrode layer and incident light wavelength when the composition ratio of MgAg is used as a parameter, Comprising: The graph in case the film thickness of the said layer is 12.5 nm. It is a graph which shows the relationship between the refractive index of a 2nd electrode layer and incident light wavelength when the composition ratio of MgAg is used as a parameter, Comprising: The graph in case the film thickness of the said layer is 20 nm. The graph which shows the simulation result of the reflectance regarding the green light in the light-emitting device of FIG. 1 when the alloy composition ratio of a 2nd electrode layer is used as a parameter. The graph which shows collectively the case where the film thickness of a 2nd electrode layer is 20 nm among the simulation results in the case of green light of FIG. 12, among the simulation results of blue light and red light. The graph which shows the simulation result of the reflectance as a visibility characteristic calculated | required based on FIG. Sectional drawing which shows the outline of the modification (the 1) of the light-emitting device which concerns on embodiment of this invention. Sectional drawing which shows the outline of the modification (the 2) of the light-emitting device which concerns on embodiment of this invention. Sectional drawing which shows the outline of the modification (the 3) of the light-emitting device which concerns on embodiment of this invention. The perspective view which shows the electronic device to which the organic electroluminescent apparatus which concerns on this invention is applied. The perspective view which shows the other electronic device to which the organic electroluminescent apparatus which concerns on this invention is applied. The perspective view which shows the further another electronic device to which the organic EL apparatus which concerns on this invention is applied.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Organic EL device as a light emitting device or an image display device, 2 (2R, 2G, 2B) ... Light emitting element, 3 ... Light emitting panel, 10 ... Substrate, 12 ... Reflective layer, 14 ... Insulator transparent layer, 18 (18R) , 18G, 18B) ... first electrode layer, 20, 20R, 20G, 20B ... light emitting functional layer, 22 ... second electrode layer as a translucent semi-reflective layer, 30 ... color filter panel, 36 (36R, 36G) 36B) Color filter.

Claims (6)

A light emitting element having a first electrode layer, a second electrode layer, and a light emitting functional layer disposed between the first electrode and the second electrode;
A reflective layer that reflects the light emitted from the light emitting functional layer toward the light emitting functional layer;
A translucent translucent layer disposed on the opposite side of the reflective layer across the light emitting functional layer, reflecting a part of the light emitted from the light emitting functional layer toward the light emitting functional layer and transmitting the other part. A reflective layer;
A color filter disposed on the opposite side of the light emitting functional layer with the translucent reflective layer interposed therebetween, and transmitting light transmitted through the translucent transflective layer;
With
The translucent semi-reflective layer state, and are one or more refractive index,
The translucent semi-reflective layer has a predetermined physical thickness t _z, and,
The optical distance from the interface on the light emitting functional layer side of the reflective layer to the interface facing the reflective layer in the translucent semi-reflective layer is based on the optical distance d ₁ calculated by Expression (2). A light-emitting device according to claim, wherein the light-emitting device is defined .
d ₁ = (p + 1/2) · λ / 2− (φ ₁ −φ ₂ ) · λ / 4π− _nz · t _z Formula (2)
Here, λ is a wavelength corresponding to the transmittance peak of the color filter,
φ ₁ is light having a wavelength λ that travels from the side opposite to the light emitting functional layer to the semitransparent semi-reflective layer.
The phase change when reflecting at the interface opposite to the light emitting functional layer of the translucent semi-reflective layer,
φ ₂ is a phase change when the light of wavelength λ traveling from the light emitting functional layer side to the reflective layer is reflected by the reflective layer,
p is a positive integer;
n _z is the refractive index of the translucent semi-reflective layer with respect to wavelength λ. The light emitting device according to claim 1, wherein a refractive index of the translucent semi-reflective layer is 3 or less. The light emitting device according to claim 2, wherein the semi-transparent reflective layer has a refractive index of 2.5 or less. The translucent semi-reflective layer includes an alloy composed of at least two kinds of unit elements,
In the case where the refractive index changes according to the change in the composition ratio of one of the unit elements and the change in the physical thickness of the translucent semi-reflective layer,
The alloy composition of the translucent transflective layer depends on the physical thickness, or
The physical thickness of the translucent semi-reflective layer is determined according to the alloy composition.
The light-emitting device according to claim 1, wherein the light-emitting device is a light-emitting device. The translucent transflective layer contains MgAg,
The light emitting device according to claim 1, wherein the light emitting device is a light emitting device. The light-emitting device according to claim 1 is provided.
An electronic device characterized by that.

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