JP2007053115A - Display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a self luminance display device which can raise a peak spectral strength of each luminous color without establishing an optical distance of a resonator of each color corresponding to red, green and blue. <P>SOLUTION: A display device is provided with a plurality of display elements in which an organic layer containing a luminous layer is held between a first electrode of an optical reflecting material and a second electrode, and either of a second electrode or the organic layer is composed to become a resonance part of the resonator structure which resonates a light generated at the luminous layer, and is composed to emit lights of red, green and blue. When a phase shift caused when a light generated at the luminous layer is reflected at both sides of the resonator is Φradian, an optical distance of the resonator is L', a peak spectral length of green out of lights generated from the luminous layer is λ, out of integers m satisfying a formula (2L)/λ+ϕ/(2π)=m (m is an integer), L' shall be set so that a formula (2L')/λ+ϕ/(2π)=m1+4 in which 4 is added on an integer m1 where L becomes a positive minimum value. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a display device, and more particularly, to a self-luminous display device such as an organic electroluminescence element.

  An element using electroluminescence of organic material (hereinafter referred to as “organic EL element”) is formed by laminating an organic hole transport layer and an organic light emitting layer between a first electrode and a second electrode. It has attracted attention as a self-luminous display element that is provided with an organic layer and can emit light with high luminance by low-voltage direct current drive.

  FIG. 1 shows a cross-sectional view of a main part of a transmissive organic EL element among such organic EL elements. The organic EL element shown in FIG. 1 is formed by laminating a transparent electrode 2, an organic buffer layer 3, an organic hole transport layer 4, an organic light emitting layer 5, and a metal electrode 6 in order from the lower layer on a transparent substrate 1. Light h generated in the organic light emitting layer 5 is extracted from the substrate 1 side.

  However, in the organic EL element shown in FIG. 1, the spectrum of the light h of each color generated and extracted from the organic light emitting layer 5 having each emission color has a wide peak width as shown in FIG. For light h, the peak wavelength is lower. For this reason, when a display device capable of color display is configured using this organic EL element, a color reproduction range sufficient to display a television image, for example, cannot be obtained.

  Therefore, in order to solve this problem, a dielectric mirror layer (not shown) is provided between the substrate 1 and the transparent electrode 2, so that the dielectric mirror layer, the organic buffer layer 3, and the organic hole transport layer 4. It has been considered to provide a resonator structure including the organic light emitting layer 5 and the metal electrode 6. In the organic EL element having this resonator structure, the light h generated in the organic light emitting layer 5 reciprocates between the dielectric mirror layer and the metal electrode 6, and only the light having the resonance wavelength is amplified from the substrate 1 side. It is taken out. For this reason, the light h having a spectrum with a high peak intensity and a narrow width can be extracted, and the color reproduction range of a display device including the organic EL element can be expanded.

  However, when the peak width of the spectrum of the extracted light h is narrowed like the organic EL element having the resonator structure as described above, the wavelength of the light h is greatly shifted when the light emitting surface is viewed from an oblique direction. The emission angle dependency of the emission characteristics is increased. For this reason, it is necessary to prevent the spectrum width of the light extracted from the organic EL element from becoming too narrow. However, this organic EL element is not designed in consideration of the viewing angle dependency as described above, and a sufficient color reproduction range cannot be maintained in a wide viewing angle.

In addition, in such an organic EL element, it is necessary to optimize the resonator structure for each color light h to be extracted, which is troublesome.
Further, in the organic EL element shown in FIG. 1, the external light entering from the outside of the element is reflected by the metal electrode 6, so that the external light reflectance is high and the contrast under the external light is low. As a technique for preventing this, Japanese Patent Laid-Open No. 9-127855 discloses an organic EL display device having a configuration in which a quarter wavelength plate and a linear polarizing plate are combined on the display surface side as shown in FIG. It is disclosed. That is, this organic EL display device is arranged by combining the quarter wavelength plate 8 and the linear polarizing plate 9 on the substrate 1 side in the organic EL element having the same configuration as described with reference to FIG. It prevents external light reflection. In addition, the metal electrode serving as the reflective surface is replaced with a transparent electrode, a light absorption layer is provided on the transparent electrode side opposite to the organic layer, and external light reflection is prevented by absorbing external light with this light absorption layer Has also been proposed. However, in the display device having such a configuration, since the extraction and reflection of the emitted light generated in the display device are hindered, the luminance is reduced to about 50%.

  Furthermore, a configuration has been proposed in which color filters that transmit red (R), green (G), and blue (B) colors are arranged on each light emitting pixel of the same color. However, the display element having such a configuration cannot suppress reflection of outside light in the same wavelength range as the emission color of each pixel, even if reflection of outside light other than the emission color can be suppressed.

Japanese Patent Laid-Open No. 9-127858

Accordingly, an object of the present invention is to provide a self-luminous display element capable of maintaining a sufficient color reproduction range over a wide viewing angle.
Another object of the present invention is to provide a self-luminous display element capable of reducing external light reflection and improving contrast without causing a reduction in luminance.
Still another object of the present invention is to provide a self-light-emitting device capable of maintaining a sufficient color reproduction range at a wide viewing angle and reducing external light reflection without causing a decrease in luminance and improving contrast. It is to provide a display device of a type.

  In order to achieve the above object, in the present invention, a light emitting layer is sandwiched between a first electrode made of a light reflecting material and a second electrode made of a transparent material, and at least one of the second electrode and the light emitting layer is A display element configured to be a resonance part of a resonator structure is characterized in that the resonance part is configured as follows.

The first display element has a phase shift that occurs when the light generated in the light emitting layer is reflected at both ends of the resonating unit as Φ radians, the optical distance of the resonating unit is L, and the light out of the light generated in the light emitting layer is extracted. When the peak wavelength of the spectrum of the desired light is λ, the optical distance L of the resonance part is configured to be a positive minimum value in a range satisfying the following expression (1).
(2L) / λ + Φ / (2π) = m (m is an integer) (1)

  In the first display element having such a configuration, since the optical distance L of the resonance part satisfies Expression (1), light in the vicinity of the wavelength λ causes multiple interference in the resonance part. In addition, since the optical distance L of the resonance part is configured to be a positive minimum value in a range that satisfies the formula (1), the spectrum of the extracted light is within a range where light of wavelength λ interferes with multiple interference. It is kept in the widest width. For this reason, in this display element, the peak intensity is increased by the multiple interference while the spectrum of the extracted light keeps a certain width. Therefore, in this display element, even when the viewing angle is shifted, the shift amount of the wavelength λ is suppressed to be small, and the color purity is improved in a wide viewing angle range.

Further, the second display element has a phase shift that occurs when light generated in the light emitting layer is reflected at both ends of the resonating portion as Φ radians, an optical distance of the resonating portion as L ′, and a peak of a green light spectrum. When the wavelength is λ, the optical distance L so as to satisfy the following formula (3) obtained by adding 4 to the integer m1 where L is a positive minimum value among the integer m satisfying the following formula (2). 'Is set.
(2L) / λ + Φ / (2π) = m (m is an integer) (2)
(2L ′) / λ + Φ / (2π) = m1 + 4 (3)

  In the second display element having such a configuration, light of each wavelength corresponding to red (R), green (G), and blue (B) has multiple interference in the resonance part. For this reason, the peak intensity of the spectrum of each luminescent color can be increased without setting the optical distance L ′ of the resonance portion for each color. Therefore, the optical distance L ′ of the resonance part can be made common in each display element corresponding to each emission color.

The third display element has a phase shift that occurs when light generated in the light emitting layer is reflected at both ends of the resonance part by Φ radians, an optical distance of the resonance part by L ′, and a peak wavelength of the spectrum of green light. In the case of λ, the optical value is set so as to satisfy the following formula (5) obtained by adding an integer q of 10 or more to the integer m1 where L is the positive minimum value among the integer m satisfying the following formula (4). A distance L ′ is set.
(2L) / λ + Φ / (2π) = m (m is an integer) (4)
(2L ′) / λ + Φ / (2π) = m1 + q (5)

  In such a display element, multiple wavelengths of light in each of the red (R), green (G), and blue (B) regions cause multiple interference in the resonance part. For this reason, in a color display device configured using this display element, the optical distance L ′ of the resonance part can be made common in each display element corresponding to each emission color. Moreover, since the light of each emission color extracted by multiple interference is composed of a plurality of peaks, the overall spectrum width of the extracted light h is apparently widened. Therefore, in this display element, even when the viewing angle is shifted, the shift amount of the wavelength λ is suppressed to be small, and the color purity is improved in a wide viewing angle range.

The fourth display element of the present invention is characterized in that a color filter that resonates at the resonance portion and transmits light extracted from the second electrode is provided above the second electrode.
In the display element having such a configuration, when the wavelength of light that is resonated at the resonance unit and extracted from the second electrode is a target wavelength, out of the external light irradiated from the second electrode side, Only light passes through the color filter and reaches the resonance part. Here, since this resonator is a resonator filter for the target wavelength, the transmittance for the target wavelength range is very high, that is, the reflectance for the light in the target wavelength range is very low. For this reason, reflection of external light in the same wavelength range as the target wavelength transmitted through the color filter can be suppressed in this resonance part. On the other hand, outside light outside the target wavelength range is prevented from entering the element by the color filter, and reflection from the color filter is suppressed. As a result, reflection of external light including light in the target wavelength range is prevented without hindering extraction of emitted light in the target wavelength range from the second electrode side.

Further, the fifth to seventh display elements are characterized by a configuration in which the fourth display element and the first to third display elements are respectively combined.
According to another invention for achieving the above object, a light emitting layer is sandwiched between the first electrode and the second electrode, and light from the first electrode and the second electrode is extracted. In the display element configured such that at least one of the light emitting layer and the light emitting layer becomes a resonance part of a resonator structure, the resonance part is configured similarly to the first to seventh display elements.

  According to still another aspect of the invention for achieving the above object, a first electrode made of a light reflecting material, a light emitting layer and a second electrode made of a transparent material are sequentially laminated on a substrate, and the second electrode and the light emitting device. In the display element configured such that at least one of the layers becomes the resonance part of the resonator structure, the resonance part is configured similarly to the first to seventh display elements.

  According to still another aspect of the invention for achieving the above object, a first electrode made of a light reflecting material, a light emitting layer and a second electrode made of a transparent material are sequentially laminated on a substrate, and the second electrode and the light emitting device. In the display element configured such that at least one of the layers becomes the resonance part of the resonator structure, the resonance part is configured similarly to the first to seventh display elements. Typically, the light emitting layer is configured to be a resonance part of the resonator structure, or the second electrode is configured to be a resonance part of the resonator structure.

  Still another invention for achieving the above object is that a light emitting layer is sandwiched between a first electrode made of a light reflecting material and a second electrode made of a transparent material. In a display element configured so that at least one of the resonators is a resonator part of the resonator structure, when the optical distance of the resonator part is L, the peak wavelength of the spectrum of the light extracted when the viewing angle changes, The difference from the peak wavelength of the internal emission spectrum (for example, the spectrum of light extracted without causing multiple interference of the light emitted from the organic light emitting layer 13c in the embodiment described later) is the half width (FWHM) of the internal emission spectrum. The optical distance L is set so as to be within half.

  As described above, according to the display element of claim 1 of the present invention, the intensity of the peak wavelength λ of this light is reduced to multiple interference while keeping the spectrum of the light extracted from the emitted light to a certain width. So that the resonator structure is optimized. Therefore, it is possible to obtain a display element in which the color purity is improved by suppressing the shift amount of the wavelength λ of the extracted light to be small in a wide viewing angle range. As a result, the color reproduction range of a display device using this display element can be expanded in a wide viewing angle range.

  Moreover, according to the display element of Claim 2, it becomes possible to resonate the emitted light of each wavelength corresponding to red (R), green (G), and blue (B) in the same resonance part. For this reason, it is not necessary to set the optical distance L of the resonance part of the display element for each emission color, and the optical distance L of the resonance part can be made common.

  Furthermore, according to the display element of claim 3, it is possible to cause multiple interference of emitted light having a number of peak wavelengths in the red (R), green (G), and blue (B) regions in the same resonance portion. become. For this reason, it is not necessary to set the optical distance L of the resonance part of the display element for each emission color, and the optical distance L of the resonance part can be made common. In addition, since the extracted light of each color can have a plurality of fine peaks, the overall spectrum width of each light can be widened. Therefore, it is possible to obtain a display element in which the color purity is improved by suppressing the shift amount of the wavelength λ of the extracted light to be small in a wide viewing angle range. As a result, the color reproduction range of a display device using this display element can be expanded in a wide viewing angle range.

  Further, according to the display element of claim 4, by arranging the resonator structure and the color filter in combination, it does not interfere with emission of light having a desired wavelength out of the emitted light, and coincides with this. Therefore, it is possible to prevent reflection of outside light in the entire wavelength range including light having a wavelength to be transmitted. Therefore, it is possible to greatly improve the contrast under external light while ensuring the luminance of the emitted light.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. Here, an embodiment of a display element in which the present invention is applied to an organic EL element will be described.
FIG. 4 shows an organic EL device according to the first embodiment of the present invention. The organic EL element shown in FIG. 4 is a so-called top emission type organic EL element. On the substrate 11, the first electrode 12, the organic layer 13, the translucent reflective layer 14, and the second electrode 15 are sequentially formed from the lower layer. It has a stacked configuration.
The board | substrate 11 is comprised with a transparent glass substrate, a semiconductor substrate, etc., for example, and may be flexible.

  The first electrode 12 is used as an anode electrode also serving as a reflective layer, and is made of a light reflective material such as platinum (Pt), gold (Au), chromium (Cr), or tungsten (W). . Moreover, it is preferable that this 1st electrode 12 is set to the range whose film thickness is 100 nm-300 nm.

  The organic layer 13 is formed, for example, by sequentially laminating an organic light emitting layer 13c serving also as a buffer layer 13a, a hole transport layer 13b, and an electron transport layer from the lower layer. In addition, you may provide an electron carrying layer as a layer different from the organic light emitting layer 13c. The buffer layer 13a is a layer for preventing leakage, such as m-MTDATA [4,4 ', 4 "-tris (3-methylphenylphenylamino) triphenylamine], 2-TNATA [4,4', 4" -tris. (2-naphtylphenylamino) triphenylamine] and the like. The buffer layer 13a may be omitted as long as the leak does not interfere with the buffer layer 13a. In addition, the hole transport layer 13b is, for example, α-NPD [N, N′-di (1-naphthyl) -N, N′-diphenyl- [1,1′-biphenyl] -4,4′-diamine]. Composed. The organic light emitting layer 13c is composed of light emitting materials having emission colors of red (R), green (G), and blue (B). For example, Alq3 (triskinolinol is used as a light emitting material having an emission color of G. Aluminum complex) is used.

  Each of these layers constituting the organic layer 13 is preferably set such that the buffer layer 13a is 15 nm to 300 nm, the hole transport layer 13b is 15 nm to 100 nm, and the organic light emitting layer 13c is 15 nm to 100 nm. However, the film thickness of the organic layer 13 and each layer constituting the organic layer 13 is set so that the optical film thickness becomes a value described later.

  The translucent reflective layer 14 constitutes a cathode electrode, and is made of, for example, magnesium (Mg), silver (Ag), or an alloy thereof. The translucent reflective layer 14 is preferably set to a thickness in the range of 5 nm to 50 nm.

Further, the second electrode 15 is made of a material generally used as a transparent electrode, such as indium tin oxide (ITO) or an oxide of indium and zinc. The second electrode 15 has a thickness in the range of 30 nm to 1000 nm. Further, a passivation film (not shown) made of a transparent dielectric is provided on the second electrode 15. This transparent dielectric preferably has a refractive index comparable to that of the material constituting the second electrode 15. As such a material, silicon oxide (SiO ₂ ), silicon nitride (SiN), or the like can be used. For example, the film is formed with a film thickness of 500 nm to 10000 nm.

In this organic EL element, the first electrode 12 made of a light reflecting material, the organic layer 13 and the translucent reflective layer 14 constitute a resonator structure, and the organic layer 13 serves as a resonance part. For this reason, the optical distance L between the first electrode 12 and the translucent reflective layer 14, that is, the optical film thickness of the resonance part made of the organic layer 13 is set so as to satisfy the following formula (6), In particular, the optical distance L _{min that} is a minimum positive value is employed. However, the phase shift generated when the light h generated in the organic light emitting layer 13c is reflected by the first electrode 12 and the semitransparent reflective layer 14 is Φ radians, and the light h to be extracted from the light h emitted from the organic light emitting layer 13c. Let λ be the peak wavelength of the spectrum.
(2L) / λ + Φ / (2π) = m (m is an integer) (6)

And the film thickness of each layer which comprises the organic layer 13 is set so that this may be satisfy | filled. Here, the optical distance L of the resonance part is determined by the refractive indexes n1, n2, and the refractive indexes n1, n2, and the like of each layer constituting the organic layer 13 (in this first embodiment, the buffer layer 13a, the hole transport layer 13b, and the organic light emitting layer 13c). .., Nk and film thicknesses d1, d2,..., Dk are obtained as in the following formula (7).
L = n1 * d1 + n2 * d2 + ... + nk * dk (7)

As a calculation example of L, the buffer layer 13a is made of 2-TNATA, the hole transport layer 13b is made of α-NPD, the organic light emitting layer 13c is made of Alq3, and their thicknesses are d1 = 32 nm, d2 = 30 nm, d3, respectively. = 50 nm and λ = 535 nm, n1 = 1.9, n2 = 1.8, and n3 = 1.7.
L = 1.9 × 32 + 1.8 × 30 + 1.7 × 50 = 200 nm
It becomes.

  Also, Φ is derived as follows. That is, first, a reflective layer (Cr, etc.) or a semi-transparent reflective layer (Mg, Ag, Mg-Ag alloy, etc.) is formed to a thickness of 200 nm or more on a substrate (for example, Si substrate), and spectroscopic ellipsometry measurement is performed. The refractive index n and absorption coefficient k of these reflective layers or translucent reflective layers are determined using an apparatus (for example, manufactured by SOPRA).

The phase shift on the reflective layer side can be calculated using n, k and the refractive index n of the organic layer in contact with the reflective layer (for example, Principles of Optics, Max Born and Emil Wolf, 1974). (For example, PERGAMON PRESS).
Similarly, the phase shift on the side of the semitransparent reflective layer also includes n, k, the refractive index n of the organic layer in contact with the semitransparent reflective layer, the film thickness of the semitransparent reflective layer, and the transparent films above it. The refractive index and the film thickness can be used for calculation. The refractive index of the organic layer and each transparent film can also be measured using a spectroscopic ellipsometry measuring device.
The sum of the above two phase shifts is Φ.
An example of the value of Φ is Φ = −4.7 radians for λ = 535 nm.

  In the organic EL element configured as described above, a resonator structure is configured by the first electrode 12, which is a reflection layer, the organic layer 13, and the semitransparent reflection layer 14, and the organic layer 13 which is a resonance part becomes a narrow band filter. Only the light h in the vicinity of the peak wavelength λ of the spectrum to be extracted is enhanced by multiple interference and extracted from the second electrode 15 side. For this reason, the light h having a spectrum with a high peak intensity is extracted. Moreover, the film thickness of the organic layer 13 (optical distance L of the resonance part) is the minimum positive value among the values in which the resonator structure is constituted by the first electrode 12, the organic layer 13, and the semitransparent reflection layer 14. Therefore, the spectrum of the extracted light h is kept in the widest range within the range where the light of wavelength λ interferes.

  FIG. 5 shows a simulation example of the spectrum of each light extracted from the organic EL element having each emission color designed in this manner (here, m = 0 in the equation (6)). Further, chromium was used for the first electrode 12 and silver-magnesium alloy was used for the translucent reflective layer 14. FIG. 6 is a spectrum simulation example showing the characteristics of each organic layer 13 designed in the same manner as a single filter. The spectrum shown in this figure and the light emitted from the organic light emitting layer 13c were extracted without causing multiple interference. The spectrum shown in FIG. 5 is obtained by multiplying the spectrum of light, that is, the internal emission spectrum shown in FIG.

  As a comparative example, FIG. 8 shows a simulation example of each spectrum of light extracted from an organic EL element that satisfies the formula (6) but the optical distance L does not become a positive minimum value (here, m = 1). Show. The organic EL element of this comparative example is configured in the same manner as the first organic EL element except for the optical distance L of the resonance part, and the organic EL element that emits light in the red (R) region is the buffer layer 13a. The organic EL element that emits light in the green (G) region has a buffer layer 13a of 190 nm, and the organic EL element that emits light in the blue (B) region has a buffer layer 13a of 150 nm. The film thickness of the organic layer 13 was adjusted. FIG. 9 is a spectrum simulation example showing the characteristics of each organic layer as a single filter designed in the same manner as in this comparative example. The spectrum shown in this figure and the light emitted from the organic light emitting layer 13c are subjected to multiple interference. The spectrum shown in FIG. 8 is obtained by multiplying the spectrum of the extracted light, that is, the internal emission spectrum shown in FIG.

  As can be seen by comparing these figures, by setting the film thickness of the organic layer 13 as in the first embodiment, the spectral width of the light h extracted from the organic EL element can be increased while causing multiple interference. It becomes possible to keep it to some extent. For this reason, in the organic EL element of the first embodiment, even when the viewing angle is shifted, the shift amount of the wavelength λ can be suppressed small, and the color purity can be improved in a wide viewing angle range.

  FIG. 10 shows the viewing angle dependency of the organic EL element (m = 0) according to the first embodiment, and the green (G) measured at angles of 0 ° (front), 30 °, and 60 ° with respect to the display surface. ) Of light having a wavelength of. FIG. 11 is a graph showing the viewing angle dependency of the organic EL element (m = 1) of the comparative example.

  As can be seen by comparing FIG. 10 and FIG. 11, in the organic EL device according to the first embodiment, the peak of the spectrum is hardly shifted even when the viewing angle is shifted by 30 °, and is shifted by 60 °. However, the peak of the spectrum is within a shift of about 10 nm. On the other hand, in the organic EL element of the comparative example, as shown in FIG. 11, the peak of the spectrum when the viewing angle is shifted by 60 ° is shifted to the short wavelength side by about 30 nm, and the color is changed. I understand. From this, in the organic EL device according to the first embodiment, the amount of shift of the peak position of the spectrum of the extracted light h can be suppressed to be smaller than that of the organic EL device according to the comparative example even when the viewing angle is increased. Was confirmed.

This is due to the following reason. That is, when viewed from an oblique direction θ radians with respect to the light emitting surface, the equation (6) can be rewritten as the following equation (8).
(2L) / λ ′ × cos θ + Φ / (2π) = m (m is an integer) (8)
Here, if λ ′ = λ + Δλ (λ is the peak wavelength of the spectrum of the filter characteristic when the light emitting surface is viewed from the front), Δλ = (1−cos θ) λ is obtained from Equation (8), and the resonator structure is It can be seen that the shift amount Δλ of the peak of the spectrum of the filter characteristics depends only on the viewing angle, regardless of the integer m that defines the film thickness of the organic layer to constitute.

  However, for the reason described later, when m is small, the spectrum of the filter characteristic is gentle and broad, that is, broad, and therefore the peak shift amount of the extracted light spectrum is small. For this reason, in the organic EL device according to the first embodiment, the color purity can be improved in a wide viewing angle range. As a result, a direct-view color display device configured using this organic EL element can ensure a sufficient color reproduction range at a wide viewing angle.

The reason why the spectrum of the filter characteristic becomes broader when m is smaller as described above is as follows. When the sum of the phase shifts of the reflected light generated by the anode electrode, that is, the first electrode 12 and the cathode electrode, that is, the semitransparent reflective layer 14 is Φ radians, the optical distance of the organic layer 13 is L, and the wavelength of the light is λ. When the amount of phase delay for one multiple interference is δ,
δ = 2π · 2L / λ + Φ (9)
It is. here,
δ = 2π · m (m is an integer) (10)
Λ that satisfies is the peak wavelength of the narrowband filter. If this is λ _max , from equations (9) and (10)
2L / λ _max + Φ / 2π = m (m is an integer) (11)
Get. As the optical distance L of the organic layer 13 becomes smaller in Equation (9), the change amount of δ with respect to the change amount of λ decreases. As can be understood, the smaller the m, the broader the spectrum width of the narrowband filter. become.

  FIG. 12 shows chromaticity coordinates (the present invention) of light extracted from the organic EL element according to the first embodiment measured by a chromatic photometer (BM-7 manufactured by Topcon Corporation). As comparative examples, chromaticity coordinates (CRT) of a CRT (cathode-ray tube) and chromaticity coordinates (conventional) corresponding to the spectrum of light extracted from the conventional organic EL element described with reference to FIG. 1 are shown. Here, in FIG. 12, the curved line portion of the outermost line indicates a spectrum locus, and the straight line portion indicates a pure boundary. As can be seen by comparing these chromaticity coordinates, the chromaticity coordinates of the organic EL device according to the first embodiment have a color reproduction range significantly larger than that of the conventional one, and are almost the same color as the CRT. It was confirmed that the reproduction range was secured.

  FIG. 13 shows an organic EL device according to the second embodiment of the present invention. The organic EL element shown in FIG. 13 is the same as that of the organic EL element according to the first embodiment shown in FIG. 4 except that the translucent reflective layer 14, the second electrode 15, and the upper end interface of the second electrode 15 (for example, the atmospheric layer) And a resonator structure. The reflectivity at the interface between the end face of the second electrode 15 and the atmospheric layer is as large as about 10%. Here, the effect of a resonator having the second electrode 15 made of a transparent material as a resonance part is used.

For this reason, the distance between the atmospheric layer and the translucent reflective layer 14, that is, the optical distance L of the resonating portion including the second electrode 15 (here, L ₂ is distinguished from the first embodiment) is as follows. An optical distance satisfying the following equation (13) in which 4 is added to m (which is written as m1) where L ₁ is a positive minimum value among m satisfying the equation (12) of L ₂ is adopted. However, the phase shift that occurs when the light h generated in the organic light emitting layer 13c is reflected at both ends of the resonance part (second electrode 15) is Φ radians, and the peak wavelength of the light spectrum is λ. When a passivation film made of a transparent dielectric material having a refractive index equivalent to that of the second electrode 15 is provided on the second electrode 15, the passivation film and the second electrode 15 are connected to the resonance portion. Become.
(2L ₁ ) / λ + Φ / (2π) = m (m is an integer) (12)
(2L ₂ ) / λ + Φ / (2π) = m1 + 4 (13)

As shown in FIG. 14, the resonating portion designed in this way (that is, the second electrode 15) multiplexes light of each wavelength corresponding to each region of red (R), green (G), and blue (B). It becomes something to interfere. Therefore, for each color, it is not necessary to set the optical distance L ₂ of the resonant section, in each of the organic EL elements corresponding to the respective emission colors, a common optical distance L ₂ of the resonant section of a second electrode 15 Can be

  FIG. 15 shows an organic EL element according to the third embodiment of the present invention. The organic EL element shown in FIG. 15 is the same as that of the organic EL element according to the first embodiment shown in FIG. 4 at the translucent reflective layer 14, the second electrode 15, and the upper end interface (for example, the atmospheric layer) of the second electrode 15. This constitutes a resonator structure.

The distance between the atmospheric layer and the translucent reflective layer 14 of this organic EL element, that is, the optical distance L of the resonance part composed of the second electrode 15 (here, L is distinguished from the first and second embodiments). ₃ ) is an integer q of 10 or more, preferably 18 or more, with respect to m satisfying the following formula (14), especially L ₁ having a positive minimum value (denoting m as m1) An optical distance L ₃ that satisfies the formula (15) obtained by adding the integer q1 is used. However, the phase shift that occurs when the light h generated in the organic light emitting layer 13c is reflected at both ends of the resonance part (second electrode 15) is Φ radians, and the peak wavelength of the light spectrum is λ. When a passivation film made of a transparent dielectric material having a refractive index equivalent to that of the second electrode 15 is provided on the second electrode 15, the passivation film and the second electrode 15 are connected to the resonance portion. Become.
(2L ₁ ) / λ + Φ / (2π) = m (m is an integer) (14)
(2L ₃ ) / λ + Φ / (2π) = m1 + q (15)

As shown in FIG. 16, the resonating unit designed in this way (that is, the second electrode 15) multiplexes multiple wavelengths of light in each of the red (R), green (G), and blue (B) regions. It will be something to let you. For this reason, similarly to the second embodiment, it is not necessary to set the optical distance L ₃ of the resonance part for each color, and in each organic EL element corresponding to each emission color, the optical distance L ₃ of the resonance part is set. Can be shared. Moreover, as shown in FIG. 17, since the light h extracted by multiple interference (light in the green (G) region in FIG. 17) has a plurality of fine peaks, the entire extracted light h The effective spectral width is substantially widened. For this reason, like the organic EL device according to the first embodiment, the color purity can be improved in a wide viewing angle range. As a result, a direct-view color display device configured using this organic EL element exhibits sufficient color reproducibility over a wide viewing angle.

  The second embodiment and the third embodiment can be applied in combination with the first embodiment or independently. Further, the configuration of the resonance unit described in the second embodiment and the third embodiment can be applied to the resonance unit including the organic layer 13. However, the resonance part described in the second embodiment and the third embodiment includes the second electrode 15 having a relatively high degree of freedom in the direction of increasing the film thickness, considering that the film thickness is relatively increased. It is suitable for the configuration as a resonance part. The structure of the resonance part described in the first embodiment can also be applied to a resonance part composed of the second electrode 15 (and the passivation film on the upper part thereof).

  Further, each of the above embodiments is not limited to application to a top emission type organic EL element as shown in FIG. For example, the anode electrode is composed of the first electrode 12 made of a metal film having a high work function, but the anode electrode is formed by overlaying a transparent conductive film on top of a reflective film such as a dielectric multilayer film or aluminum (Al). A layer structure may be used. In this case, this reflective film becomes the first electrode in the present invention. And a transparent conductive film comprises a part of resonance part.

  As shown in FIG. 18, the first electrode 12 is a cathode electrode made of a light reflecting material, the second electrode 15 is an anode electrode made of a transparent electrode, and the organic light emitting layer 13c and holes are sequentially formed from the first electrode 12 side. The present invention can also be applied to a configuration in which the transport layer 13b and the buffer layer 13c are stacked. In this case, the organic layer 13 and the second electrode 15 are combined into one resonance part, and the light generated in the organic light emitting layer 13c is transmitted to the lower end of the organic layer 13 (the boundary surface with the first electrode 12) and the second electrode 14. Reflected at the top edge of the surface (boundary surface with the atmospheric layer). In such a configuration, a translucent reflective layer (not shown) made of a material having a high work function such as Pt, Au, or Cr is provided between the organic layer 13 and the second electrode 15. It can also be applied to those. In this case, the structure of the resonance part is the same as that of the first to third embodiments.

  Furthermore, although the description with reference to the drawings is omitted, the present invention is not limited to the top emission type organic EL element, and can also be applied to a transmission type organic EL element using the transparent substrate 11. is there. Further, the present invention can be applied to an organic EL element connected to a thin film transistor on the substrate 11.

  FIG. 19 is a cross-sectional view of a principal part showing an organic EL element according to the fourth embodiment of the present invention. The organic EL element shown in FIG. 19 has a configuration in which a color filter is further provided to the top emission organic EL element according to the first embodiment shown in FIG. That is, with the organic layer 13 as a resonance part, a resonator structure is configured by the reflective layer composed of the first electrode 12, the organic layer 13, and the semitransparent reflective layer 14, and on the semitransparent reflective layer 14, the second electrode ( A color filter 20 is arranged via a transparent electrode 15 and a passivation film 16.

  In particular, the color filter 20 transmits only light h in the vicinity of the peak wavelength λ of the spectrum desired to be extracted from the organic EL element. That is, an element that emits light in the red (R) region is provided with a color filter 20R that transmits only light in the red (R) region, and green (B) is provided in an element that emits light in the green (G) region. A color filter 20G that transmits only light in the region is provided, and an element that emits light in the blue (B) region is provided with a color filter 20B that transmits only light in the blue (B) region.

  Then, as described in the first embodiment, the optical distance L of the resonance portion made of the organic layer 13 is maintained at the widest range in the range where the light h in the vicinity of the peak wavelength λ of the extracted light is subjected to multiple interference. Designed to lean. Furthermore, it is desirable to match the wavelength range of the light h desired to be extracted from each organic layer 13 with the wavelength range where the transmittance of each color filter 20 is high.

In the organic EL element having such a configuration, only the light H _{1 in the} vicinity of the peak wavelength λ of the spectrum to be extracted from the organic EL element is colored out of the external light H irradiated from the display surface side (that is, the color filter 20 side). It passes through the filter 20 and reaches the resonance part (here, the organic layer 13), and external light having other wavelengths is prevented from entering the inside of the element from the color filter 20.

Here, since this resonance part (that is, the organic layer 13) is a narrow band filter that transmits light in the vicinity of the peak wavelength λ to be extracted, the transmittance for the external light H _{1 in the} vicinity of the peak wavelength λ is very high. That is, the reflectance with respect to the external light H ₁ is very low. Therefore, the reflection of the external light H _{1 in the} vicinity of the peak wavelength λ that has entered from the color filter 20 is suppressed in the organic layer 13, and is prevented from being transmitted through the color filter 20 and emitted to the outside again.

  FIG. 20 shows a simulation result of the external light reflectance of an organic EL element having a structure in which no color filter is arranged (that is, the organic EL element shown in FIG. 4). In FIG. 20, B represents external light reflection of a blue (B) light emitting organic EL element, G represents external light reflection of a green (G) light emitting organic EL element, and R represents red (G) light emission. The external light reflection of the organic EL element is shown. As shown in FIG. 20, it can be seen that each organic EL element has a low external light reflectance near the peak wavelength λ of each emission color. That is, in the blue light-emitting organic EL element, the reflection of external light in the blue (B) region is suppressed to a low level, and in the red light-emitting and green light-emitting organic EL elements as well, outside the wavelength region intended for display. Light reflection is suppressed.

  FIG. 21 shows the transmission characteristics of the color filters (20R, 20G, 20B) arranged in each organic EL element. In FIG. 21, B represents the transmission characteristics of the color filter disposed in the blue (B) light emitting organic EL element, and G represents the transmission characteristics of the color filter disposed in the green (G) light emitting organic EL element. R represents the transmission characteristics of a color filter disposed in an organic EL element emitting red (R) light. As shown in FIG. 21, each color filter has a high transmittance around the peak wavelength λ of each emission color.

Here, when the external light reflectance of the organic EL element shown in FIG. 4 in which no color filter is arranged is R (λ) and the transmittance of the color filter is T (λ), the color filter is provided. The external light reflectance Rt (λ) of the organic EL element shown in FIG. 19 is expressed as the following formula (16).
Rt (λ) = T (λ) × R (λ) × T (λ) (16)

  FIG. 22 shows a simulation result obtained by synthesizing the graphs of FIGS. 20 and 21 based on the equation (16) as the external light reflectance of the organic EL element shown in FIG. In FIG. 22, B represents external light reflection of a blue (B) light emitting organic EL element, G represents external light reflection of a green (G) light emitting organic EL element, and R represents red (G) light emission. The external light reflection of the organic EL element is shown. As shown in FIG. 22, it can be seen that each organic EL element can suppress the external light reflectance in a wide wavelength region including the peak wavelength λ of each emission color.

  On the other hand, light h in the vicinity of the peak wavelength λ to be extracted out of the emitted light generated in the organic layer 13 passes through the narrow band filter (organic layer 13) as it is, and further passes through the color filter 20 and is extracted as display light. It is. For this reason, the luminance of the emitted light generated in the organic EL element is regulated only by the transmittance of the color filter. However, each organic EL element is provided with a color filter having a high transmittance of light in the vicinity of the peak wavelength λ to be extracted from the emitted light generated in the organic EL element. For this reason, the reduction in the extraction efficiency of emitted light due to the arrangement of the color filter can be suppressed to a low level, and the reduction in luminance can be minimized.

  As a result, the organic EL element reflects external light H including light in the vicinity of the peak wavelength λ without disturbing the extraction of light h in the vicinity of the peak wavelength λ to be extracted out of the emitted color. Is prevented. Therefore, it is possible to greatly improve the contrast under external light while ensuring the luminance of the emitted light.

In addition, in this organic EL element, the wavelength range that is resonated and extracted by the organic layer 13 is matched with the wavelength range with high transmittance in each color filter 20, so that the wavelength transmitted through the color filter 20 is the same. Reflection of the outside light H _{1 in} the range can be effectively suppressed in the organic layer 13.
In addition, as in the first embodiment, the light h extracted from the organic EL element can be subjected to multiple interference, but the spectrum width can be kept to a certain extent, so that the color can be adjusted within a wide viewing angle range. The purity can also be improved.

  In the fourth embodiment, the organic EL element having a configuration in which a color filter is further provided to the top emission type organic EL element according to the first embodiment shown in FIG. 4 has been described. However, the present invention is not limited to this, and the organic EL elements having the respective configurations described in the first embodiment, the second embodiment, or the third embodiment may be provided with a color filter. However, the color filter disposed in each organic EL element has the transmittance characteristics as described above.

  And in the organic EL element of the structure which provided the color filter with respect to each structure demonstrated in 2nd Embodiment, the contrast under external light is improved significantly, ensuring the brightness | luminance of emitted light similarly to the above-mentioned. In addition, it is possible to obtain the same effect as that of the second embodiment, that is, the effect that the optical distance L of the resonance unit corresponding to each emission color can be shared.

  In addition, in the organic EL element having the color filter provided for each component described in the third embodiment, the contrast under the external light is greatly improved while ensuring the luminance of the emitted light as described above. In addition, it is possible to obtain the same effect as that of the third embodiment, that is, the effect that the color purity can be improved in a wide viewing angle range.

  When the organic EL element according to the fourth embodiment is also applied to an organic EL element having a structure for extracting emitted light from the substrate side, for example, as shown in FIG. A second electrode 32, a translucent reflective layer 33 also serving as an anode electrode, an organic layer 34 composed of a buffer layer 34a, a hole transport layer 34b and an organic light emitting layer 34c, and a first electrode 35 serving as a cathode electrode also serving as a reflective layer. The color filter 20 selected as appropriate is placed in combination on the opposite side of these layers with the transparent substrate 31 in between. The color filter 20 may be disposed between the transparent substrate 31 and the second electrode 32.

It is principal part sectional drawing which shows the structure of the conventional organic EL element. It is a basic diagram which shows the spectrum of each color taken out from the conventional organic EL element. It is a basic diagram which shows the structural example of the conventional display element aiming at prevention of external light reflection. It is principal part sectional drawing which shows the organic EL element by 1st Embodiment of this invention. It is a basic diagram which shows the example of a simulation of the spectrum of each light taken out from the organic EL element by 1st Embodiment of this invention. It is a basic diagram which shows the example of a spectrum simulation which shows the filter characteristic of the organic layer single-piece | unit in the organic EL element by 1st Embodiment of this invention. It is a basic diagram which shows the example of a simulation of the internal light emission spectrum in the organic EL element by 1st Embodiment of this invention. It is a basic diagram which shows the example of a simulation of the spectrum of each light taken out from the conventional organic EL element. It is a basic diagram which shows the example of a spectrum simulation which shows the filter characteristic of the organic layer single-piece | unit in the conventional organic EL element. It is a basic diagram which shows the viewing angle dependence of the organic EL element (G light emission) by 1st Embodiment of this invention. It is a basic diagram which shows the viewing angle dependence of the conventional organic EL element (G light emission). It is a basic diagram which shows the chromaticity coordinate of the organic EL element by 1st Embodiment of this invention, and its comparative example. It is principal part sectional drawing which shows the organic EL element by 2nd Embodiment of this invention. It is a basic diagram which shows the example of a spectrum simulation which shows the filter characteristic of the organic layer single-piece | unit in the organic EL element by 2nd Embodiment of this invention. It is principal part sectional drawing which shows the organic EL element by 3rd Embodiment of this invention. It is a basic diagram which shows the example of a spectrum simulation which shows the filter characteristic of the organic layer single-piece | unit in the organic EL element by 3rd Embodiment of this invention. It is a basic diagram which shows the example of a simulation of the spectrum of the light extracted from the organic EL element (G light emission) by 3rd Embodiment of this invention. It is principal part sectional drawing which shows the other organic EL element to which this invention is applied. It is principal part sectional drawing which shows the organic EL element by 4th Embodiment of this invention. It is a basic diagram which shows the example of a spectrum simulation which shows the external light reflection characteristic in the case of the organic EL element by 4th Embodiment of this invention when there is no color filter. It is a basic diagram which shows the spectrum which shows the transmission characteristic of each color filter provided in the organic EL element by 4th Embodiment of this invention. It is a basic diagram which shows the example of a spectrum simulation which shows the external light reflection characteristic in the organic EL element by 4th Embodiment of this invention. It is principal part sectional drawing which shows the other structural example of the organic EL element by 4th Embodiment of this invention.

Explanation of symbols

  12, 35 ... first electrode, 13, 34 ... organic layer, 13c, 34c ... organic light emitting layer, 14, 33 ... translucent reflective layer, 15, 32 ... second electrode, 20 ... color filter

Claims (15)

An organic layer including a light emitting layer is sandwiched between a first electrode made of a light reflecting material and a second electrode made of a transparent material, and at least one of the second electrode and the organic layer emits light in the light emitting layer. In a display device including a plurality of display elements each configured to be a resonance part of a resonator structure that resonates light, each configured to emit red, green, or blue light,
The phase shift that occurs when the light generated in the light emitting layer is reflected at both ends of the resonating unit is Φ radians, the optical distance of the resonating unit is L ′, and the green light out of the light emitted from the light emitting layer When the peak wavelength of the spectrum is λ, the formula (2L) / λ + Φ / (2π) = m (m is an integer)
An expression in which L is an integer m1 in which L is a positive minimum value among integers m satisfying (2L ′) / λ + Φ / (2π) = m1 + 4
The optical distance L ′ is set so as to satisfy the above. An organic layer including a light emitting layer is sandwiched between a first electrode made of a light reflecting material and a second electrode made of a transparent material, and at least one of the second electrode and the organic layer emits light in the light emitting layer. In a display device including a plurality of display elements each configured to be a resonance part of a resonator structure that resonates light, each configured to emit red, green, or blue light,
On the opposite side of the second electrode from the light emitting layer side, a color filter that resonates at the resonance portion and transmits light extracted from the second electrode side is provided.
The phase shift that occurs when the light generated in the light emitting layer is reflected at both ends of the resonating unit is Φ radians, the optical distance of the resonating unit is L ′, and the green light out of the light emitted from the light emitting layer When the peak wavelength of the spectrum is λ, the formula (2L) / λ + Φ / (2π) = m (m is an integer)
An expression in which L is an integer m1 in which L is a positive minimum value among integers m satisfying (2L ′) / λ + Φ / (2π) = m1 + 4
The optical distance L ′ is set so as to satisfy the above. An organic layer including a light emitting layer is sandwiched between the first electrode and the second electrode, and at least one of the first electrode and the second electrode from which light is extracted and at least one of the organic layers is In a display device including a plurality of display elements each configured to be a resonance part of a resonator structure that resonates light emitted from the light emitting layer, each configured to emit red, green, or blue light,
The phase shift that occurs when the light generated in the light emitting layer is reflected at both ends of the resonating unit is Φ radians, the optical distance of the resonating unit is L ′, and the green light out of the light emitted from the light emitting layer When the peak wavelength of the spectrum is λ, the formula (2L) / λ + Φ / (2π) = m (m is an integer)
An expression in which L is an integer m1 in which L is a positive minimum value among integers m satisfying (2L ′) / λ + Φ / (2π) = m1 + 4
The optical distance L ′ is set so as to satisfy the above. An organic layer including a light emitting layer is sandwiched between the first electrode and the second electrode, and at least one of the first electrode and the second electrode from which light is extracted and at least one of the organic layers is In a display device including a plurality of display elements each configured to be a resonance part of a resonator structure that resonates light emitted from the light emitting layer, each configured to emit red, green, or blue light,
Light extracted from the side of the first electrode and the second electrode from which the light is extracted, on the side opposite to the light-emitting layer side, which is resonated by the resonating unit and from which the light is extracted And a color filter that passes through
The phase shift that occurs when the light generated in the light emitting layer is reflected at both ends of the resonating unit is Φ radians, the optical distance of the resonating unit is L ′, and the green light out of the light emitted from the light emitting layer When the peak wavelength of the spectrum is λ, the formula (2L) / λ + Φ / (2π) = m (m is an integer)
An expression in which L is an integer m1 in which L is a positive minimum value among integers m satisfying (2L ′) / λ + Φ / (2π) = m1 + 4
The optical distance L ′ is set so as to satisfy the above. A first electrode made of a light reflecting material, an organic layer including a light emitting layer, and a second electrode made of a transparent material are sequentially stacked on the substrate, and at least one of the second electrode and the organic layer emits light from the light emitting layer. In a display device comprising a plurality of display elements each configured to be a resonating part of a resonator structure that resonates the emitted light, each configured to emit red, green, or blue light,
The phase shift that occurs when the light generated in the light emitting layer is reflected at both ends of the resonating unit is Φ radians, the optical distance of the resonating unit is L ′, and the green light out of the light emitted from the light emitting layer When the peak wavelength of the spectrum is λ, the formula (2L) / λ + Φ / (2π) = m (m is an integer)
An expression in which L is an integer m1 in which L is a positive minimum value among integers m satisfying (2L ′) / λ + Φ / (2π) = m1 + 4
The optical distance L ′ is set so as to satisfy the above. A first electrode made of a light reflecting material, an organic layer including a light emitting layer, and a second electrode made of a transparent material are sequentially stacked on the substrate, and at least one of the second electrode and the organic layer emits light from the light emitting layer. In a display device comprising a plurality of display elements each configured to be a resonating part of a resonator structure that resonates the emitted light, each configured to emit red, green, or blue light,
Above the second electrode, a color filter that resonates at the resonance unit and transmits light extracted from the second electrode side is provided,
The phase shift that occurs when the light generated in the light emitting layer is reflected at both ends of the resonating unit is Φ radians, the optical distance of the resonating unit is L ′, and the green light out of the light emitted from the light emitting layer When the peak wavelength of the spectrum is λ, the formula (2L) / λ + Φ / (2π) = m (m is an integer)
An expression in which L is an integer m1 in which L is a positive minimum value among integers m satisfying (2L ′) / λ + Φ / (2π) = m1 + 4
The optical distance L ′ is set so as to satisfy the above. A resonator structure in which a first electrode made of a light reflecting material, an organic layer including a light emitting layer, and a second electrode made of a transparent material are sequentially laminated on a substrate, and the organic layer resonates light emitted from the light emitting layer. In a display device comprising a plurality of display elements each configured to emit red, green or blue light,
The phase shift that occurs when the light generated in the light emitting layer is reflected at both ends of the resonating unit is Φ radians, the optical distance of the resonating unit is L ′, and the green light out of the light emitted from the light emitting layer When the peak wavelength of the spectrum is λ, the formula (2L) / λ + Φ / (2π) = m (m is an integer)
An expression in which L is an integer m1 in which L is a positive minimum value among integers m satisfying (2L ′) / λ + Φ / (2π) = m1 + 4
The optical distance L ′ is set so as to satisfy the above. A resonator structure in which a first electrode made of a light reflecting material, an organic layer including a light emitting layer, and a second electrode made of a transparent material are sequentially laminated on a substrate, and the organic layer resonates light emitted from the light emitting layer. In a display device comprising a plurality of display elements each configured to emit red, green or blue light,
Above the second electrode, a color filter that resonates at the resonance unit and transmits light extracted from the second electrode side is provided,
The phase shift that occurs when the light generated in the light emitting layer is reflected at both ends of the resonating unit is Φ radians, the optical distance of the resonating unit is L ′, and the green light out of the light emitted from the light emitting layer When the peak wavelength of the spectrum is λ, the formula (2L) / λ + Φ / (2π) = m (m is an integer)
An expression in which L is an integer m1 in which L is a positive minimum value among integers m satisfying (2L ′) / λ + Φ / (2π) = m1 + 4
The optical distance L ′ is set so as to satisfy the above. A resonator in which a first electrode made of a light reflecting material, an organic layer including a light emitting layer, and a second electrode made of a transparent material are sequentially laminated on the substrate, and the second electrode resonates light emitted from the light emitting layer. In a display device including a plurality of display elements each configured to be a resonance part of a structure, each configured to emit red, green, or blue light,
The phase shift that occurs when the light generated in the light emitting layer is reflected at both ends of the resonating unit is Φ radians, the optical distance of the resonating unit is L ′, and the green light out of the light emitted from the light emitting layer When the peak wavelength of the spectrum is λ, the formula (2L) / λ + Φ / (2π) = m (m is an integer)
An expression in which L is an integer m1 in which L is a positive minimum value among integers m satisfying (2L ′) / λ + Φ / (2π) = m1 + 4
The optical distance L ′ is set so as to satisfy the above. A resonator in which a first electrode made of a light reflecting material, an organic layer including a light emitting layer, and a second electrode made of a transparent material are sequentially laminated on the substrate, and the second electrode resonates light emitted from the light emitting layer. In a display device including a plurality of display elements each configured to be a resonance part of a structure, each configured to emit red, green, or blue light,
Above the second electrode, a color filter that resonates at the resonance unit and transmits light extracted from the second electrode side is provided,
The phase shift that occurs when the light generated in the light emitting layer is reflected at both ends of the resonating unit is Φ radians, the optical distance of the resonating unit is L ′, and the green light out of the light emitted from the light emitting layer When the peak wavelength of the spectrum is λ, the formula (2L) / λ + Φ / (2π) = m (m is an integer)
An expression in which L is an integer m1 in which L is a positive minimum value among integers m satisfying (2L ′) / λ + Φ / (2π) = m1 + 4
The optical distance L ′ is set so as to satisfy the above. An organic layer including a light emitting layer is sandwiched between a first electrode made of a light reflecting material and a second electrode made of a transparent material, and at least one of the second electrode and the organic layer emits light in the light emitting layer. In a display device including a plurality of display elements each configured to be a resonance part of a resonator structure that resonates light, each configured to emit red, green, or blue light,
When the wavelength of light that is resonated and extracted by the resonance unit is a target wavelength, the resonance unit transmits external light in the target wavelength range so as to prevent reflection of external light in the target wavelength range. Composed and
The phase shift that occurs when the light generated in the light emitting layer is reflected at both ends of the resonating unit is Φ radians, the optical distance of the resonating unit is L ′, and the green light out of the light emitted from the light emitting layer When the peak wavelength of the spectrum is λ, the formula (2L) / λ + Φ / (2π) = m (m is an integer)
An expression in which L is an integer m1 in which L is a positive minimum value among integers m satisfying (2L ′) / λ + Φ / (2π) = m1 + 4
The optical distance L ′ is set so as to satisfy the above. An organic layer including a light emitting layer is sandwiched between the first electrode and the second electrode, and at least one of the first electrode and the second electrode from which light is extracted and at least one of the organic layers is In a display device including a plurality of display elements each configured to be a resonance part of a resonator structure that resonates light emitted from the light emitting layer, each configured to emit red, green, or blue light,
When the wavelength of light that is resonated and extracted by the resonance unit is a target wavelength, the resonance unit transmits external light in the target wavelength range so as to prevent reflection of external light in the target wavelength range. Composed and
The phase shift that occurs when the light generated in the light emitting layer is reflected at both ends of the resonating unit is Φ radians, the optical distance of the resonating unit is L ′, and the green light out of the light emitted from the light emitting layer When the peak wavelength of the spectrum is λ, the formula (2L) / λ + Φ / (2π) = m (m is an integer)
An expression in which L is an integer m1 in which L is a positive minimum value among integers m satisfying (2L ′) / λ + Φ / (2π) = m1 + 4
The optical distance L ′ is set so as to satisfy the above. A first electrode made of a light reflecting material, an organic layer including a light emitting layer, and a second electrode made of a transparent material are sequentially stacked on the substrate, and at least one of the second electrode and the organic layer emits light from the light emitting layer. In a display device comprising a plurality of display elements each configured to be a resonating part of a resonator structure that resonates the emitted light, each configured to emit red, green, or blue light,
When the wavelength of light that is resonated and extracted by the resonance unit is a target wavelength, the resonance unit transmits external light in the target wavelength range so as to prevent reflection of external light in the target wavelength range. Composed and
The phase shift that occurs when the light generated in the light emitting layer is reflected at both ends of the resonating unit is Φ radians, the optical distance of the resonating unit is L ′, and the green light out of the light emitted from the light emitting layer When the peak wavelength of the spectrum is λ, the formula (2L) / λ + Φ / (2π) = m (m is an integer)
An expression in which L is an integer m1 in which L is a positive minimum value among integers m satisfying (2L ′) / λ + Φ / (2π) = m1 + 4
The optical distance L ′ is set so as to satisfy the above. A resonator structure in which a first electrode made of a light reflecting material, an organic layer including a light emitting layer, and a second electrode made of a transparent material are sequentially laminated on a substrate, and the organic layer resonates light emitted from the light emitting layer. In a display device comprising a plurality of display elements each configured to emit red, green or blue light,
When the wavelength of light that is resonated and extracted by the resonance unit is a target wavelength, the resonance unit transmits external light in the target wavelength range so as to prevent reflection of external light in the target wavelength range. Composed and
The phase shift that occurs when the light generated in the light emitting layer is reflected at both ends of the resonating unit is Φ radians, the optical distance of the resonating unit is L ′, and the green light out of the light emitted from the light emitting layer When the peak wavelength of the spectrum is λ, the formula (2L) / λ + Φ / (2π) = m (m is an integer)
An expression in which L is an integer m1 in which L is a positive minimum value among integers m satisfying (2L ′) / λ + Φ / (2π) = m1 + 4
The optical distance L ′ is set so as to satisfy the above. A resonator in which a first electrode made of a light reflecting material, an organic layer including a light emitting layer, and a second electrode made of a transparent material are sequentially laminated on the substrate, and the second electrode resonates light emitted from the light emitting layer. In a display device including a plurality of display elements each configured to be a resonance part of a structure, each configured to emit red, green, or blue light,
When the wavelength of light that is resonated and extracted by the resonance unit is a target wavelength, the resonance unit transmits external light in the target wavelength range so as to prevent reflection of external light in the target wavelength range. Composed and
The phase shift that occurs when the light generated in the light emitting layer is reflected at both ends of the resonating unit is Φ radians, the optical distance of the resonating unit is L ′, and the green light out of the light emitted from the light emitting layer When the peak wavelength of the spectrum is λ, the formula (2L) / λ + Φ / (2π) = m (m is an integer)
An expression in which L is an integer m1 in which L is a positive minimum value among integers m satisfying (2L ′) / λ + Φ / (2π) = m1 + 4
The optical distance L ′ is set so as to satisfy the above.

Images