KR-102962715-B1 - Display apparatus

KR102962715B1KR 102962715 B1KR102962715 B1KR 102962715B1KR-102962715-B1

Abstract

A display device according to one example of the present invention comprises: an OLED (organic light emitting device) substrate that generates incident light mixed with the blue incident light and the green incident light, wherein the structure comprises at least one blue light emitting unit that emits blue incident light and at least one green light emitting unit that emits green incident light; a first pixel, a second pixel, and a third pixel that emit a first color light, a second color light, and a third color light on the OLED substrate; a color conversion layer comprising quantum dots disposed on at least two of the first to third pixels and converting light incident from the OLED substrate into light of a predetermined color; and a first to third color filter disposed on the first to third pixels and absorbing or blocking light of a predetermined wavelength band; wherein the difference between the wavelength at the maximum transmittance of the second color filter and the center of gravity wavelength of the green incident light can be adjusted to be 18 nm or less.

Inventors

곽승연
강병준
김형준
심명선
이금희
이방린
이성훈
최병기
황규영

Assignees

삼성디스플레이 주식회사

Dates

Publication Date: 20260508
Application Date: 20200918

Claims (16)

An OLED (organic light emitting device) substrate comprising at least one blue light-emitting unit emitting blue incident light and at least one green light-emitting unit emitting green incident light; A first pixel, a second pixel, and a third pixel disposed on the OLED substrate and emitting incident light mixed with the blue incident light and the green incident light; A first color conversion layer and a second color conversion layer comprising quantum dots disposed in two or more of the first pixel, the second pixel and the third pixel, and converting light incident from the OLED substrate into light of a predetermined color; and A first color filter positioned on the first color conversion layer, which is disposed on the first pixel, the second pixel, and the third pixel to absorb or block light of a predetermined wavelength band, a second color filter positioned on the second color conversion layer, and a third color filter; Includes, The conversion value (R) of the spectral area (Area) in the wavelength range of 380 nm to 780 nm of the green incident light for the difference (Δλ) between the maximum transmittance wavelength (λg) of the second color filter and the center of gravity wavelength (λc) of the green incident light is 3.6 to 13, and Here, the area of the spectrum is determined by the following Equation 1, and [Formula 1] In the above Equation 1, f(x) is the spectrum of the green incident light normalized to a maximum light intensity of 1, and the center of gravity wavelength (λc) is the wavelength that divides the area of the spectrum of the green incident light in half, and The transformation value (R) is determined by the following Equation 3 [Equation 3] Display device.
In Article 1, The above OLED substrate has a tandem structure Display device.
In Article 1, The above OLED substrate comprises a first blue light-emitting unit, a green light-emitting unit, and a second blue light-emitting unit stacked sequentially. Display device.
In Paragraph 3, A first charge generation layer provided between the first blue light-emitting unit and the green light-emitting unit; and A second charge generating layer provided between the green light-emitting unit and the second blue light-emitting unit; further comprising Display device.
In Article 1, The above green light-emitting unit includes an organic-based green light-emitting layer, and The green light-emitting layer above includes a TADF (thermally activated delayed fluorescence) dopant. Display device.
In Article 1, The above green light-emitting unit includes an organic-based green light-emitting layer, and The above green light-emitting layer includes a phosphorescent dopant, and The above phosphorescent dopant satisfies T1(dopant) ≤ S1(dopant) ≤ T1(dopant) + 0.5 eV, where T1(dopant) is the triplet energy level (eV) of the phosphorescent dopant and S1(dopant) is the singlet energy level (eV) of the phosphorescent dopant. Display device.
In Article 6, The above phosphorescent dopant is an organometallic compound containing iridium (Ir). Display device.
In Article 6, The above phosphorescent dopant is an organometallic compound comprising platinum (Pt), osmium (Os), titanium (Ti), zirconium (Zr), hafnium (Hf), europium (Eu), terbium (Tb), thulium (Tm), rhodium (Rh), ruthenium (Ru), rhenium (Re), beryllium (Be), magnesium (Mg), aluminum (Al), calcium (Ca), manganese (Mn), cobalt (Co), copper (Cu), zinc (Zn), gallium (Ga), germanium (Ge), rhodium (Rh), palladium (Pd), silver (Ag), or gold (Au). Display device.
In Article 6, The above phosphorescent dopant is an organometallic compound having a square-planar coordination structure. Display device.
In Article 6, The phosphorescent dopant comprises a metal M and an organic ligand, wherein the metal M and the organic ligand form one, two, or three cyclometallated rings. Display device.
In Article 6, The phosphorescent dopant comprises a metal M and a tetracoordinate organic ligand capable of forming three or four cyclometallated rings, and The above metal M comprises platinum (Pt), osmium (Os), titanium (Ti), zirconium (Zr), hafnium (Hf), europium (Eu), terbium (Tb), thulium (Tm), rhodium (Rh), ruthenium (Ru), rhenium (Re), beryllium (Be), magnesium (Mg), aluminum (Al), calcium (Ca), manganese (Mn), cobalt (Co), copper (Cu), zinc (Zn), gallium (Ga), germanium (Ge), rhodium (Rh), palladium (Pd), silver (Ag), or gold (Au), and The above-mentioned tetracoordinate organic ligand comprises a benzimidazole group or a pyridine group. Display device.
In Article 1, The first color filter mentioned above is a blue and green cut filter, and The above second color filter is a blue cut filter. Display device.
In Article 1, The above-mentioned first color filter is an absorption type red color filter, and The above second color filter is an absorbent green color filter. Display device.
In Article 1, The above third color filter is a green cut filter or an absorbent blue color filter. Display device.
In Article 1, The display device further includes a fourth pixel, and the region of the fourth pixel is configured to express a color different from the region of the first pixel, the second pixel, and the third pixel. Display device.
In Article 15, The area of the fourth pixel above is a blank area, Display device.

Description

Display apparatus The disclosed embodiments relate to a display device. A display device is a device that visually displays data. Display devices are used as display units for small products such as mobile phones, as well as for large products such as televisions. A display device includes multiple pixels that receive electrical signals and emit light to display an image externally. Each pixel includes a light-emitting element; for example, in the case of an organic light-emitting display device, it includes an organic light-emitting diode (OLED) as the light-emitting element. Generally, an organic light-emitting display device forms thin-film transistors and organic light-emitting diodes on a substrate, and operates by the organic light-emitting diode emitting light on its own. In an organic light-emitting diode (OLED) display comprising multiple quantum dot color conversion elements and color filters, a blue-OLED substrate, a white-OLED substrate, or a green-OLED substrate can be used as a light source. FIG. 1 is a schematic perspective view illustrating a display device according to one embodiment of the present invention. FIG. 2 is a schematic plan view of a display device according to one embodiment of the present invention. FIG. 3 is a cross-sectional view schematically illustrating a display device according to one embodiment of the present invention. FIG. 4 is a cross-sectional view showing an enlarged portion of a display device according to one embodiment of the present invention. FIG. 5 is an enlarged view illustrating a color conversion layer and a color filter according to one embodiment of the present invention. FIG. 6 is a cross-sectional view showing more specifically the configuration of an OLED substrate that can be applied to a display device according to an exemplary embodiment. FIG. 7 is a graph showing the emission spectrum of green incident light generated from a green light-emitting unit according to one embodiment of the present invention and the output light that has passed through a first color filter to a third color filter. FIG. 8a is a graph showing the change in transmittance according to wavelength of the first to third color filters according to one embodiment of the present invention. Figure 8b is a graph showing the UHD (4K) color standard established by the International Telecommunication Union (ITU) in the CIE1931 chromaticity diagram. FIG. 9a is a graph showing the spectral shape and center of gravity wavelength of green incident light according to one embodiment of the present invention. Figure 9b is a graph in which the change in transmittance according to the wavelength of the second color filter is added to the graph of Figure 9a. FIG. 9c is a graph showing the spectral shape of green incident light according to one example. FIG. 9d is a graph showing the relationship between the transformed value according to one example, the color coordinates of the green region, and the transmittance of the blue incident light. FIG. 10 is a cross-sectional view of an OLED substrate and a color conversion unit according to another embodiment of the present invention. FIG. 11 is a cross-sectional view of an OLED substrate and a color conversion unit according to another embodiment of the present invention. FIG. 12 is a cross-sectional view of an OLED substrate and a color conversion unit according to another embodiment of the present invention. Hereinafter, a display device according to embodiments will be described in detail with reference to the attached drawings. The widths and thicknesses of the layers or regions depicted in the attached drawings may be slightly exaggerated for the clarity of the specification and convenience of explanation. Throughout the detailed description, the same reference numerals indicate the same components. The present invention is capable of various modifications and may have various embodiments; specific embodiments are illustrated in the drawings and described in detail in the detailed description. The effects and features of the present invention, and the methods for achieving them, will become clear by referring to the embodiments described below in detail together with the drawings. However, the present invention is not limited to the embodiments disclosed below but can be implemented in various forms. Hereinafter, embodiments of the present invention will be described in detail with reference to the attached drawings. When describing with reference to the drawings, identical or corresponding components are given the same reference numerals, and redundant descriptions thereof will be omitted. In the following embodiments, terms such as first, second, etc. are used not in a limiting sense, but for the purpose of distinguishing one component from another component. In the following examples, singular expressions include plural expressions unless the context clearly indicates otherwise. In the following embodiments, terms such as "include" or "hav