JP2012248517A - Light emitting device and electronic apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce irregularities at pixel parts as much as possible and suppress color mixture due to reflection from a vertical conduction part while maintaining high light extraction efficiency, in a top emission type light emitting device comprising a combination of a white organic EL element and a resonance structure.SOLUTION: A light emitting device E1 has an optical structure in which an expression of D={(2πm+φ+φ)/4π}λ is satisfied, where D represents a distance between a reflective layer 12 and a counter electrode 22, φrepresents a phase shift in reflection at the reflective layer 12, φrepresents a phase shift in reflection at the counter electrode 22, λ represents a peak wavelength of a standing wave generated between the reflective layer 12 and the counter electrode 22, and m represents an integer of 2 or less. In the light emitting device E1, a length from an interface between a pixel electrode 15 and a vertical conduction part 330 to the counter electrode 22 is set to a value from the distance D at which a red peak wavelength can be obtained when m is equal to 0 in the expression to the distance D at which a blue peak wavelength can be obtained when m is equal to 1 in the expression.

Description

  The present invention relates to a light emitting device using various light emitting elements and an electronic apparatus including the light emitting device.

  In recent years, a top emission type light-emitting device in which an organic EL (electroluminescence) element is formed as a light-emitting layer on a substrate and light emitted from the light-emitting element is extracted on the side opposite to the substrate has been widely used as a display device for electronic devices. In the top emission method, a light emitting element is sandwiched, a reflective layer is formed between the substrate and one first electrode (for example, an anode) formed on the substrate side, and the other second electrode (for example, a cathode) is sandwiched between the light emitting layers. This is a method of extracting light from the side, and is a method with high light use efficiency.

In a top emission type light emitting device, a technology is disclosed in which a white organic EL element is used to resonate light having a predetermined wavelength between the second electrode and the reflective layer, thereby increasing light extraction efficiency ( For example, Non-Patent Document 1). In this technique, the peak wavelength in the resonance structure is λ, the optical distance from the reflective layer to the second electrode is D, the phase shift in reflection at the reflective layer is φ _L , and the phase shift in reflection at the second electrode is An optical structure that satisfies the following formula is proposed, where φ _{U is} an integer m.
D = {(2πm + φ _L + φ _U ) / 4π} λ (1)

  In particular, in the above formula (1), when m = 0, light of a wide wavelength can be extracted with a certain degree of efficiency while simplifying the array structure in the organic EL element. Can be realized and it is easy to make high-definition pixels.

  However, in the light emitting device having an optical structure in which m = 0 in the formula (1), the red pixel, the green pixel, and the blue pixel are extracted in order to extract light in all the red region, the green region, and the blue region. It is necessary to perform color separation with a color filter or the like. Therefore, there has been a problem that the bandwidth of the emission spectrum on the observation side is widened and the color purity is poor. In addition, when compared in the red, green, and blue wavelength regions, there is a problem that the light extraction efficiency is low. As a result, there is a problem that the power consumption of the light emitting device is increased, which is disadvantageous as panel characteristics.

  Further, in order to increase the light extraction efficiency, the transparent layer and the electrode layer are formed so that the optical distance D of the second electrode from the reflective layer satisfying the above expression (1) is different for each of the red pixel, the green pixel, and the blue pixel. A light emitting device having a set thickness has also been proposed.

  However, in such a light emitting device, when forming a light emitting layer made of an organic EL element, there is a problem that the uneven shape of the lower layer greatly affects the light emission characteristics. In particular, in such a light-emitting device, it is difficult to flatten the pixel surface, the edge portion of the pixel electrode, and the like. Therefore, the layer thickness of the light-emitting layer changes, and the optical distance D changes. In addition to the output light wavelength, light of other wavelengths may be output. As a result, there has been a problem that display quality is lowered, such as color purity is lowered.

  Therefore, as in Patent Document 1, a light emitting device has been proposed in which each of the second electrodes (pixel electrodes) has a larger area than the reflective layer so as to overlap the entire reflective layer.

JP 2007-280677 A

SID2010 P-146 / S.Lee, Samsung Mobile Display Co., Ltd

However, in the light emitting device as disclosed in Patent Document 1, a vertical conduction portion is provided in order to establish conduction between a circuit element formed on the lower substrate or a wiring portion connected to the circuit element and the second electrode (pixel electrode). Is provided. However, it is difficult to flatten the vertical conduction part, and there is a problem that the optical distance D changes as described above.
In addition, since a metal material such as aluminum is used for the vertical conduction portion, light from the light emitting layer is reflected by the vertical conduction portion to cause color mixing, resulting in a problem that the color gamut becomes narrow. .

  Against this background, the present invention is a top emission type light emitting device that combines a white organic EL element and a resonant structure, while maintaining high light extraction efficiency and minimizing the irregularities of the pixel portion, and The object is to solve the problem of suppressing color mixing due to reflection from the vertical conduction part.

In order to solve the above-described problems, a light-emitting device according to the present invention includes a red light-emitting element, a blue light-emitting element, and a green light-emitting element, and a substrate on which a circuit element is formed. Each of the element, the blue light emitting element, and the green light emitting element includes a light reflecting layer formed on the substrate, a transparent layer formed on the light reflecting layer, and a pixel formed on the transparent layer. An electrode, a light-emitting layer formed on the transparent layer and the pixel electrode, a counter electrode formed on the light-emitting layer, and a vertical conduction part for conducting the circuit element and the pixel electrode, The distance between the light reflection layer and the counter electrode is D, the phase shift in reflection at the light reflection layer is φ _L , and the phase shift in reflection at the counter electrode is φ _U , and is generated between the light reflection layer and the counter electrode The peak wavelength of the standing wave is λ, 2 or less When the integer of m is m, it has an optical structure satisfying the following formula: D = {(2πm + φ _L + φ _U ) / 4π} λ (2), and from the interface between the vertical conduction portion and the pixel electrode The length to the counter electrode is a value from the distance D at which red peak wavelength is obtained when m = 0 in the above formula to the distance D at which blue peak wavelength is obtained when m = 1 in the above formula. Is set to

  In the present invention, the film thickness from the interface of the vertical conduction part to the pixel electrode to the counter electrode is determined from the distance D at which a red peak wavelength is obtained when m = 0 in the formula (2). Since the value is set up to the distance D at which a blue peak wavelength is obtained when m = 1 in the equation, it is difficult to extract light in the visible light region in the region sandwiched between the upper and lower conductive portions and the counter electrode. Become. As a result, the generation of reflected light from the upper and lower conductive portions is suppressed, color mixing due to the reflected light is eliminated, and the color gamut is reduced.

  In the light emitting device according to the present invention, it is preferable that the light emitting layer is integrally formed with the same film thickness in the red light emitting element, the green light emitting element, and the blue light emitting element. In this case, the light emitting layer can be integrally formed without being distinguished by the red light emitting element, the green light emitting element, and the blue light emitting element, and thus the light emitting device can be easily manufactured.

  In the light emitting device according to the present invention, the vertical conduction portion may be formed of Al, Cr, Mo, Ti, TiN, W, Cu, or an alloy containing these as main components. According to the present invention, even when the vertical conduction part is formed of Al having a high reflectivity or an alloy containing Al as a main component, light in a visible light region is present in a region sandwiched between the vertical conduction part and the counter electrode. Becomes difficult to take out. As a result, the generation of reflected light from the upper and lower conductive portions is suppressed, color mixing due to the reflected light is eliminated, and the color gamut is reduced. In addition, if the vertical conduction part is made of Cr, Mo, Ti, TiN, W, Cu, or an alloy containing these as a main component, the reflectance is low, so that the reflected light from the vertical conduction part is generated. Is further suppressed.

  In the light emitting device according to the present invention, the pixel electrode may be formed of a transparent conductive film, and the film thickness of the pixel electrode may be the same in a red pixel, a green pixel, and a blue pixel. According to the present invention, unevenness of the pixel portion is suppressed as much as possible, and variation in the distance D in the above equation (2) is suppressed. As a result, color mixing is eliminated and the color gamut is suppressed from being narrowed.

  In the light emitting device according to the present invention, an insulating layer may be formed between the vertical conduction portion and the counter electrode. According to the present invention, since there is an insulating layer on the vertical conduction part, reflected light from the vertical conduction part is more reliably suppressed.

  An electronic apparatus according to the present invention includes the light emitting device. Since the electronic apparatus according to the present invention includes the light emitting device, power consumption can be reduced.

It is typical sectional drawing which shows the outline | summary of the light-emitting device of Example 1 which concerns on one Embodiment of this invention. It is a figure which shows the material used for the positive hole transport layer, the light emitting layer, and the electron carrying layer in FIG. The peak wavelength in the resonant structure is λ, the optical distance from the reflective layer to the second electrode is D, the phase shift in reflection at the first electrode is φ _L , the phase shift in reflection at the second electrode is φ _U , and the integer is m In the optical structure satisfying the equation D = {(2πm + φ _L + φ _U ) / 4π} λ, the relationship between the integer m, the thickness between the reflective films, and the peak wavelength is shown. It is typical sectional drawing which shows the outline | summary of the light-emitting device of Example 4 which concerns on one Embodiment of this invention. It is a perspective view which shows the structure of the mobile personal computer which employ | adopted the light-emitting device which concerns on embodiment of FIG. 1 as a display apparatus. It is a perspective view which shows the structure of the mobile telephone which employ | adopted the light-emitting device which concerns on embodiment of FIG. 1 as a display apparatus. It is a perspective view which shows the structure of the portable information terminal which employ | adopted the light-emitting device which concerns on embodiment of FIG. 1 as a display apparatus.

Hereinafter, various embodiments according to the present invention will be described with reference to the accompanying drawings. In the drawings, the ratio of dimensions of each part is appropriately changed from the actual one.
<A: Example 1>
<A-1: Structure of light emitting device>
FIG. 1 is a schematic cross-sectional view showing an outline of a light emitting device E1 according to an embodiment of the present invention. The light emitting device E1 has a configuration in which a plurality of light emitting elements U1, U2, and U3 are arranged on the surface of the first substrate 10. In FIG. 1, for convenience of explanation, light emitting elements of red, green, and blue colors are used. U1, U2, and U3 are illustrated one by one.
The light emitting device E1 of the present embodiment is a top emission type, and light generated by the light emitting elements U1, U2, U3 travels toward the side opposite to the first substrate 10. Therefore, an opaque plate material such as a ceramic or metal sheet can be used as the first substrate 10 in addition to a light-transmitting plate material such as glass. In the present embodiment, the thickness of the first substrate 10 is 0.5 mm.
Although wiring for supplying light to the light emitting elements U1, U2, and U3 to emit light is arranged on the first substrate 10, illustration of the wiring is omitted. In addition, a circuit element thin film 11 for supplying power to the light emitting elements U1, U2, and U3 is disposed on the first substrate 10.

An interlayer insulating film 301 is formed on the first substrate 10 on which the circuit element thin film 11 is disposed in order to form a contact hole 360. The interlayer insulating film 301 is formed of SiO ₂ or SiN.

  On the interlayer insulating film 301, the reflective layer 12 is formed. The reflective layer 12 is formed of a material having light reflectivity. As this type of material, for example, a single metal such as Al (aluminum), Ag (silver), Au (gold), Cu (copper), or an alloy mainly composed of Au, Cu, or Ag is preferably used. The In this embodiment, the reflective layer 12 is made of Al and has a thickness of 100 nm.

A transparent layer 302 is formed on the reflective layer 12. The transparent layer 302 is formed of SiO ₂ or SiN. In this embodiment, the thickness of the transparent layer 302 is changed for each of the red light emitting element U1, the green light emitting element U2, and the blue light emitting element U3. And the counter electrode 22 are adjusted. In the present embodiment, in the red light emitting element U1, the transparent layer 302 has three layers and the layer thickness is 150 nm. Further, in the green light emitting device U2, the transparent layer 302 is formed in two layers and the layer thickness is set to 100 nm. Further, in the blue light emitting element U3, the transparent layer 302 is one layer and the layer thickness is 70 nm.

  A pixel electrode (anode) 15 is formed on the transparent layer 302. In the present embodiment, the pixel electrode 15 is formed of an ITO transparent conductive film. In this embodiment, since the distance between the reflective layer 12 and the counter electrode 22 is adjusted by the transparent layer 302, the film thickness of the pixel electrode 15 in the red light emitting element U1, the green light emitting element U2, and the blue light emitting element U3. The same film thickness is set. As an example, in the present embodiment, the film thickness of the pixel electrode 15 is set to 20 nm. Thus, in this embodiment, since the film thickness of the pixel electrode 15 was made the same in each color light emitting element, the unevenness | corrugation of a pixel part can be reduced as much as possible.

  A vertical conduction portion 330 is formed so as to fill the contact hole 360 described above, and conduction between the circuit element film 11 and the pixel electrode 15 is achieved. In the present embodiment, Al (aluminum) is used for the vertical conduction portion 330.

  An OLED layer 16 is formed on the pixel electrode 15. The OLED layer 16 includes a hole transport layer (HTL) formed on the hole injection layer, a light emitting layer (EML) formed on the hole transport layer, and a light emitting layer. It consists of the formed electron transport layer (ETL: Electron Transport Layer). In this example, the OLED layer 16 is integrally formed in the light emitting elements U1, U2, U3, and has the same film thickness.

In the present embodiment, the hole transport layer (HTL) is formed of α-NPD as shown in FIG. In the present embodiment, the thickness of the hole transport layer is 40 nm.
The light emitting layer (EML) is formed of an organic EL material that emits light by combining holes and electrons. In the present embodiment, the organic EL material is a low molecular material and emits white light. As the red host material and the red dopant material, and the green and blue host materials, those shown in FIG. 2 are used. Further, DPAVBi (4,4′-bis [2- {4- (N, N-diphenylamino) phenyl} vinyl] biphenyl) is used as a blue dopant material. Quinacridone is used as the green dopant material. In the present embodiment, the thickness of the light emitting layer (EML) is 50 nm.
The electron transport layer (ETL) is formed of Alq3 (tris 8-quinolinolato aluminum complex) as shown in FIG. In this embodiment, the thickness of the electron transport layer is 40 nm.

  A counter electrode 22 (cathode) is formed on the OLED layer 16. The counter electrode 22 is formed so as to cover the OLED layer 16 and is continuous over the plurality of light emitting elements U1, U2, and U3. The counter electrode 22 functions as a transflective layer having a property of transmitting part of the light reaching the surface and reflecting the other part (that is, transflective), such as magnesium or silver. It is formed from a single metal or an alloy mainly composed of magnesium or silver. In the present embodiment, the counter electrode 30 is made of MgAg (magnesium silver alloy). The thickness of the counter electrode 22 was 10 nm.

  A sealing layer 30 is formed on the counter electrode 22. The sealing layer 30 is formed from a transparent resin material, for example, a curable resin such as an epoxy resin. In the present embodiment, the sealing layer 30 is formed of a curable resin such as an epoxy resin, and the layer thickness is set to 400 nm. On the sealing layer 30, red, green, and blue color filters 40, 41, and 42 and a light shielding film 32 are formed. Furthermore, a second substrate 50 is provided on the red, green, and blue color filters 40, 41, and 42 and the light shielding film 32, and the second substrate 50 is attached to the first substrate 10 with the sealing layer 30 interposed therebetween. Adapted. The second substrate 50 is formed of a light transmissive material such as glass. The thickness of the second substrate 50 was 0.5 mm.

  In the light emitting elements U1, U2, and U3 of the present embodiment, a resonator structure that resonates light emitted from the OLED layer 16 is formed between the reflective layer 12 and the counter electrode 22 as the light extraction side translucent reflective layer. . Thereby, the light of a specific wavelength can be taken out efficiently.

<A-2: Optical structure>
Next, the optical structure in the light emitting device E1 of the present embodiment will be described. The light emitting device E1 in the present embodiment sets a standing wave from the reflective layer 12 to the counter electrode 22 by setting an optical distance from the reflective layer 12 to the counter electrode 22 as the light extraction side translucent reflective layer to a predetermined value. Resonance structure that generates

Specifically, the optical distance between the reflective layer 12 and the counter electrode 22 is D, the phase shift in reflection at the reflective layer 12 is φ _L , the phase shift in reflection at the counter electrode 22 is φ _U , and the standing wave When the peak wavelength is λ and the integer is m, the structure satisfies the following formula.
D = {(2πm + φ _L + φ _U ) / 4π} λ (3)

  In the above formula (3), the refractive index n of the OLED layer 16 and the transparent layer 302 between the Al reflective layer 12 and the MgAg counter electrode 22 is 1.8, and the optical distance between the reflective layer 12 and the counter electrode 22 is 1.8. FIG. 3 is a diagram in which peak wavelengths are plotted assuming D, an integer m, and red, green, and blue colors.

  As shown in FIG. 3, it can be understood that light in the visible light region is difficult to extract in the shaded region of 150 to 200 nm. That is, the film thickness from Al to MgAg is such that the red peak wavelength in the optical structure when m = 0 in the above equation (3) is obtained, and the optical when m = 1 in the above equation (3). It can be seen that light in the visible light region is difficult to extract if it is set between the film thickness and the blue peak wavelength in the structure.

  In the present embodiment, as shown in FIG. 1, the Al vertical conduction part 330 is in contact with the pixel electrode 15 of the transparent conductive film. Therefore, by setting the film thickness (the film thickness indicated by the arrow D4 in FIG. 1) from the upper surface of the vertical conduction part 330 to the MgAg counter electrode 22 to be 150 to 200 nm, it is opposed to the vertical conduction part 330. From the region sandwiched between the electrodes 22, it becomes difficult to extract light in the visible light region. As a result, it is difficult for reflected light from the vertical conduction portion 330 to be generated, color mixture can be suppressed, and the color gamut can be prevented from being narrowed.

  In the present embodiment, the film thickness of the OLED layer 16 is set to 130 nm, and the film thickness of the pixel electrode 15 is set to 20 nm. Therefore, the film thickness from the upper surface of the Al vertical conduction part 330 to the MgAg counter electrode 22 (the film thickness indicated by the arrow D4 in FIG. 1) is set to 150 nm.

  Further, the film thickness between the reflective layer 12 and the counter electrode 22 in the red light emitting element U1 (the film thickness indicated by the arrow D1 in FIG. 1), and the film thickness between the reflective layer 12 and the counter electrode 22 in the green light emitting element U2 (see FIG. 1 and the film thickness between the reflective layer 12 and the counter electrode 22 in the blue light emitting element U3 (film thickness indicated by the arrow D3 in FIG. 1) are respectively when m = 1. It is set to satisfy the above equation (3). Therefore, in each pixel region of the red light emitting element U1, the green light emitting element U2, and the blue light emitting element U3, light of each color can be extracted with high light extraction efficiency. In addition, as described above, it is difficult for reflected light from the vertical conduction portion 330 to be generated, so that the occurrence of color mixing can be suppressed, and the color gamut can be prevented from becoming narrow.

<B: Example 2>
Next, the light emitting device of Example 2 of the present embodiment will be described. The example of FIG. 1 described in Example 1 is a calculation result when the reflective layer is made of Al and the counter electrode is made of MgAg, but even when a material other than Al is used as the reflective layer, the visible light region is similarly displayed. There is a film thickness where almost no light can be obtained. Therefore, even when a material other than Al is used for the vertical conduction portion 330, the film thickness from the vertical conduction portion 330 to the counter electrode 22 is set to the red peak wavelength in the optical structure when m = 0 in the above equation (3). And the film thickness at which the blue peak wavelength in the optical structure when m = 1 in the above equation (3) is obtained, it becomes difficult to extract light in the visible light region. Generation of reflected light from the conducting portion 330 can be suppressed.

  Example 2 is an example in which a material other than Al is used for the vertical conduction part 330. If a metal material having a reflectance lower than that of Al is used for the vertical conduction part 330, generation of reflected light from the vertical conduction part 330 can be suppressed more reliably.

  In the second embodiment, therefore, Cr (chromium), Mo (molybdenum), titanium (Ti), titanium nitride (TiN), tungsten (W), or the like is used for the vertical conduction portion 330. In particular, tungsten (W) is a material often used as a material of the vertical conduction part 330, and the vertical conduction part 330 can be easily formed in the manufacturing process. Further, Cr, Ti, TiN, and W also have an advantage that no electrolytic corrosion occurs even when they come into contact with ITO of the transparent conductive film.

In Example 2, the vertical conduction part 330 is formed of Cr (chromium), Mo (molybdenum), titanium (Ti), titanium nitride (TiN), tungsten (W), etc., and from the vertical conduction part 330 to the counter electrode 22. Of the optical structure when m = 0 in the above equation (3) and the blue peak wavelength in the optical structure when m = 1 in the above equation (3) Is set between the film thickness and
As a result, it becomes difficult to extract light in the visible light region, and since the reflectance of the vertical conduction part 330 is lower than that of Al, generation of reflected light from the vertical conduction part 330 can be suppressed more reliably.

<C: Example 3>
Next, a light emitting device of Example 3 of the present embodiment will be described. In Example 3, the vertical conduction part 330 was formed of Cu (copper) or an alloy containing Cu as a main component.
By using a material having Cu or Cu as a main component for the vertical conduction part 330, the reflectance in the red region is high, but the reflectance in the blue region is low, and the light in the visible light region is not emitted. There is an advantage that it is easy.
In addition, when the vertical conduction part 330 is made of Cu or a material mainly composed of Cu, the vertical conduction part 330 can be easily formed by a damascene method, and can be manufactured on a semiconductor production line using Si or the like. There are advantages.
According to the third embodiment, it is difficult to extract light in the visible light region, and the reflectance of the vertical conduction portion 330 is lower than that of Al, so that the generation of reflected light from the vertical conduction portion 330 is more reliably suppressed. Can do. In addition, the vertical conduction portion 330 can be easily manufactured.

<D: Example 4>
Next, the light-emitting device of Example 4 of this embodiment is demonstrated based on FIG. In Example 3, as shown in FIG. 4, an insulating layer 370 is provided between the vertical conduction portion 330 and the counter electrode 22. The insulating layer 370 is formed of SiO ₂ or SiN.
By providing the insulating layer 370 between the vertical conduction part 330 and the counter electrode 22, the reflected light from the vertical conduction part 330 can be more reliably prevented.

  Also in Example 4, the film thickness from the vertical conduction part 330 to the counter electrode 22 is such that the red peak wavelength in the optical structure when m = 0 in the above equation (3) is obtained, and (3) above. It sets between the film thickness from which the blue peak wavelength in the optical structure in the case of m = 1 is obtained by a type | formula.

Further, the insulating layer 370 may be provided in any light emitting device from the first embodiment to the third embodiment between the vertical conduction portion 330 and the counter electrode 22. In the example of FIG. 4, the insulating layer 370 is formed so as not to overlap the pixel electrode 15 of the adjacent light emitting element, but the present invention is not limited to this example. For example, the pixel electrode 15 and the insulating layer 370 of the green light emitting element U2 may be covered and the insulating layer 370 may be overlapped with the end of the pixel electrode 15 of the adjacent red light emitting element U1. That is, the insulating layer 370 in FIG. 4 may be formed so as to overlap with the end portion of the pixel electrode 15 of the adjacent light emitting element.
According to the fourth embodiment, it is difficult to extract light in the visible light region, and the vertical conduction portion 330 is covered with the insulating layer 370, and therefore, the generation of reflected light from the vertical conduction portion 330 can be further reliably suppressed. .

<E: Application example>
Next, an electronic apparatus using the light emitting device according to the present invention will be described. FIG. 5 is a perspective view showing a configuration of a mobile personal computer adopting the light emitting device E1 according to the above-described embodiment as a display device. The personal computer 2000 includes a light emitting device E1 as a display device and a main body 2010. The main body 2010 is provided with a power switch 2001 and a keyboard 2002. Since the light emitting device E1 uses an organic EL element, it is possible to display an easy-to-see screen with a wide viewing angle.

  FIG. 6 shows a configuration of a mobile phone to which the light emitting device E1 according to the above-described embodiment is applied. The cellular phone 3000 includes a plurality of operation buttons 3001, scroll buttons 3002, and a light emitting device E1 as a display device. By operating the scroll button 3002, the screen displayed on the light emitting device E1 is scrolled.

  FIG. 7 shows a configuration of a portable information terminal (PDA: Personal Digital Assistant) to which the light emitting device E1 according to the above-described embodiment is applied. The information portable terminal 4000 includes a plurality of operation buttons 4001, a power switch 4002, and a light emitting device E1 as a display device. When the power switch 4002 is operated, various kinds of information such as an address book and a schedule book are displayed on the light emitting device E1.

  Electronic devices to which the light emitting device according to the present invention is applied include those shown in FIGS. 5 to 7, digital still cameras, televisions, video cameras, car navigation devices, pagers, electronic notebooks, electronic papers, calculators. , Word processors, workstations, videophones, POS terminals, printers, scanners, copiers, video players, devices equipped with touch panels, and the like.

  In the embodiment described above, the optical structure of each light emitting element has been described for the case where the integer m is 1 in the above formula (3), but the present invention is not limited to this, and the integer m is The present invention can also be applied when the number is two or more.

DESCRIPTION OF SYMBOLS 10 ... 1st board | substrate, 11 ... Circuit element thin film, 12 ... Reflective layer, 15 ... Pixel electrode, 16 ... OLED layer, 22 ... Counter electrode, 30 ... Sealing layer, 32 ... Light shielding film 40 …… Red color filter, 41 …… Green color filter, 42 …… Blue color filter, 50 …… Second substrate, 301 …… Interlayer insulating film, 302 …… Transparent layer, 330 …… Vertical conduction 360, contact hole, 370, insulating film, E1, light emitting device, U1, red light emitting element, U2, green light emitting element, U3, blue light emitting element.

Claims (6)

A light emitting device comprising a red light emitting element, a blue light emitting element, and a green light emitting element, and a substrate on which a circuit element is formed,
Each of the red light emitting element, the blue light emitting element, and the green light emitting element is
A light reflecting layer formed on the substrate;
A transparent layer formed on the light reflecting layer;
A pixel electrode formed on the transparent layer;
A light emitting layer formed on the transparent layer and the pixel electrode;
A counter electrode formed on the light emitting layer;
A vertical conduction part for conducting the circuit element and the pixel electrode;
The distance between the light reflection layer and the counter electrode is D, the phase shift in reflection at the light reflection layer is φ _L , the phase shift in reflection at the counter electrode is φ _U , and the distance between the light reflection layer and the counter electrode is When the peak wavelength of the generated standing wave is λ, and an integer equal to or less than 2 is m, the following formula D = {(2πm + φ _L + φ _U ) / 4π} λ
Having an optical structure satisfying
The length from the interface between the vertical conduction part and the pixel electrode to the counter electrode is the distance D from which the red peak wavelength is obtained when m = 0 in the equation, and the length when m = 1 in the equation. It is set to a value up to the distance D at which the blue peak wavelength is obtained,
A light emitting device characterized by that.   The light emitting device according to claim 1, wherein the light emitting layer is integrally formed with the same film thickness in the red light emitting element, the green light emitting element, and the blue light emitting element.   3. The light emitting device according to claim 1, wherein the vertical conduction portion is formed of Al, Cr, Mo, Ti, TiN, W, Cu, or an alloy containing these as a main component.   4. The pixel electrode is formed of a transparent conductive film, and the film thickness of the pixel electrode is the same in the red light emitting element, the green light emitting element, and the blue light emitting element. The light emitting device according to any one of the above.   5. The light emitting device according to claim 1, wherein an insulating layer is formed between the vertical conduction portion and the counter electrode. An electronic apparatus comprising the light emitting device according to any one of claims 1 to 5.

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