KR101927206B1 - Quantum rod luminescent display device - Google Patents

Abstract

The present invention provides a liquid crystal display comprising: a first substrate on which a plurality of pixel regions are defined; A first electrode formed on each pixel region of the first substrate; And a plurality of quantum rods formed on the first electrode and having a plurality of quantum rods oriented in one direction in parallel with the first substrate surface or a plurality of quantum rods oriented perpendicularly to the first substrate plane. A quantum rod layer; A second electrode formed on the quantum rod layer; A second substrate facing the first substrate; And a backlight unit provided on an outer surface of the first substrate.

Description

[0001] The present invention relates to a quantum rod luminescent display device,

BACKGROUND OF THE INVENTION 1. Field of the Invention [0002] The present invention relates to a quantum rod light emitting display device, and more particularly, to a quantum rod light emitting display device having an improved lifetime with low voltage and high efficiency.

2. Description of the Related Art Flat panel displays having excellent characteristics such as thinning, lightening, and low power consumption have been widely developed and applied to various fields.

As a representative flat panel display device, a liquid crystal display device has been widely used and widely used.

However, referring to FIG. 1 (a diagram showing a schematic sectional configuration of a general liquid crystal display device), a liquid crystal display device includes first and second substrates (not shown), an alignment film (not shown), a color filter layer A liquid crystal panel 10 including a liquid crystal layer (not shown), a backlight unit 20 including a plurality of optical films 22, and upper and lower polarizers 31 and 32.

That is, the liquid crystal display device 1 requires a large number of optical films 22 and polarizers 31 and 32 for gray level implementation, and a color filter layer (not shown) is formed in a separate liquid crystal panel ).

Therefore, the light emitted from the light source (not shown) of the backlight unit 20 is mostly lost while passing through the optical film 22, the color filter layer (not shown) and the polarizing plates 31 and 32, have.

That is, when the amount of light emitted from the light source (not shown) of the backlight unit 20 is 100, the amount of light finally transmitted through the liquid crystal display device 1 is about 5 to 10, There are many difficulties in implementing low power consumption required for products.

Accordingly, a new flat panel display device capable of solving the problem of low transmittance and high power consumption of such a liquid crystal display device is recently required.

Meanwhile, an organic electroluminescent device has been proposed, which does not require a separate polarizing plate, a color filter layer and an optical film in response to demands of the time.

Such an organic electroluminescent display is a device that injects electric charge into an organic light emitting layer formed between a cathode, which is an electron injection electrode, and an anode, which is a hole injection electrode, and pairs electrons and holes and then extinguishes light.

Such an organic electroluminescent device can be formed not only on a flexible substrate such as a plastic but also has excellent color sensitivity due to self-luminescence and can be driven at a lower voltage (10 V or less) than a liquid crystal display device, Is relatively small.

However, such an organic electroluminescent device has a large difference in the lifetime of the organic light emitting material of the organic light emitting layer, and the blue light emitting material has a relatively small lifetime, which is smaller than the lifetime of a typical display device .

Referring to FIG. 2 (an enlarged view of the organic light emitting layer and the light emitting auxiliary layer formed on the upper and lower portions of the organic light emitting layer in the general organic electroluminescent device), the organic electroluminescent device has a hole and electron A hole injection layer 52, a hole transport layer 54, an electron transport layer 56, and an electron injection layer 58 are formed on the lower and upper portions of the organic light emitting layer 50 in order to increase the recombination probability And the light emitting layer 60 substantially consists of five thin films. In order to form such multilayer light-emission assisting layers 52, 54, 56 and 58, a lot of processing time is required, and the material cost is also increased, which ultimately raises the manufacturing cost.

Accordingly, there is a demand for a flat panel display device having a high transmittance, capable of driving a low power consumption, having a low manufacturing cost, and having a lifetime at the level of a liquid crystal display device.

SUMMARY OF THE INVENTION The present invention has been conceived to solve the above-mentioned problems, and it is an object of the present invention to provide a polarizing plate, a polarizing plate and a plurality of optical films which do not require a large transmission efficiency and can be driven with low power consumption, And it is an object of the present invention to provide a display device having a low cost and a life time of about the liquid crystal display device.

A quantum rod light emitting display device according to an embodiment of the present invention includes a first substrate on which a plurality of pixel regions are defined; A first electrode formed on each pixel region of the first substrate; And a plurality of quantum rods formed on the first electrode and having a plurality of quantum rods oriented in one direction in parallel with the first substrate surface or a plurality of quantum rods oriented perpendicularly to the first substrate plane. A quantum rod layer; A second electrode formed on the quantum rod layer; A second substrate facing the first substrate; And a backlight unit provided on an outer surface of the first substrate.

The quantum rod layer is patterned for each pixel region, and the pixel region is divided into first, second, and third pixel regions emitting red, green, and blue, and the quantum rod layer includes first, second, The second substrate may be provided with red, green, and blue color filter patterns corresponding to the first, second, and third pixel regions, respectively.

In addition, the pixel region is divided into first, second, and third pixel regions that emit red, green, and blue light, and the quantum rod layer has quantum regions of the same size on the entire display region having the plurality of pixel regions, And a red, green and blue color filter pattern corresponding to the first, second and third pixel regions is formed on the second substrate.

The first substrate is provided with first, second and third pixel regions which exhibit red, green and blue. The quantum rod layer has quantum rods of the same size in each pixel region. Green, and blue color filter patterns corresponding to the first, second, and third pixel regions, respectively.

A gate line and a data line crossing the first substrate to define the pixel regions; And a thin film transistor connected to the gate wiring and the data wiring. The first electrode is connected to the drain electrode of the thin film transistor.

The plurality of quantum rods are aligned in one direction in parallel with the first substrate surface,

The first and second reference lines, the polarization ratio PR _h in the horizontal direction and the polarization ratio PR _v in the vertical direction are PR _h = I _h / (I _h + I _v ) and PR _v = I _v / (I _h + I _v ), the polarization ratio PR _{h in} the horizontal direction or the polarization ratio PR _v in the vertical direction is larger than 0.5 and smaller than 1, 0.5 < PR _h (or PR _v ) < 1.

The quantum rod is composed of only a core or a shell surrounding the core and the core. The shell has a shape having a minor axis and a major axis, and a ratio of the minor axis to the major axis is 1: 1.1 to 1:30 Wherein the core of the quantum rod has one of a spherical shape, an elliptical shape, a polyhedron shape, and a rod shape, and the shell has a cut surface cut in a minor axis direction of the quantum rod, And the like.

In addition, the shell has a single layer or a multi-layer structure, and the shell is made of an alloy, an oxide-based material, or an impurity-doped material.

The core is characterized in that it is made of semiconductors, alloys or mixed materials of Group II-VI, III-V, III-VI, VI-IV and IV on the periodic table. In the case of a III-V group, it may be made of one selected from the group consisting of InP, InN (HfSe, HgTe, and CdZnSe), or a mixture of two or more materials selected from the group consisting of CdSe, CdS, CdTe, ZnO, ZnSe, ZnS, ZnTe, , Or a material in which one or more of two or more materials are made of GaN, InSb, InAsP, InGaAs, GaAs, GaP, GaSb, AlP, AlN, AlAs, AlSb, CdSeTe and ZnCdSe. , PbSe, PbTe, PbS, PbSnTe, and Tl ₂ SnTe ₅ , or a material in which two or more materials are mixed.

The backlight unit generates blue or ultraviolet light having a short wavelength of 430 nm or less. The backlight unit includes a reflection plate, a light guide plate disposed on the reflection plate, a light source disposed on a side of the light guide plate, And a plurality of optical sheets positioned at the upper portion of the light guide, or a reflective plate, a light source positioned above the reflection plate, a diffusion plate positioned above the light source, And is a direct-type backlight unit comprising a plurality of optical sheets.

The present invention is characterized in that only a quantum rod layer arranged in one direction between a first electrode and a second electrode is provided to improve the transmittance of a liquid crystal display device, thereby enabling low power consumption driving, .

Further, since the fluorescence efficiency is high without forming a separate light-emission assisting layer in the upper and lower portions of the quantum rod layer, the number of the light-emission-assisting layers can be reduced even if the multilayer light- The contrast processing time can be shortened and the manufacturing cost can be reduced.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a schematic sectional view of a general liquid crystal display device. Fig.
BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to an organic electroluminescent device, and more particularly,
Figure 3 illustrates a general form of a quantum rod;
Fig. 4 is a view showing the state of electrons and majors before and after application of an electric field and a form of a quantum rod; Fig.
5 is a sectional view of a quantum rod light emitting device according to the first embodiment of the present invention.
6 is a sectional view of a quantum rod light emitting device according to a second embodiment of the present invention.
7 is a view schematically showing only a first substrate and a quantum rod in a quantum rod light emitting device according to the first embodiment of the present invention.
8 is a cross-sectional view schematically showing only a first substrate and a quantum rod in a quantum rod light emitting display device in which a quantum rod is arranged so as to form a tilt angle larger than 0 degrees with respect to a first substrate surface as a comparative example;
9A is a sectional view of a quantum rod light emitting display device according to a first modification of the first and second embodiments of the present invention.
FIG. 9B is a sectional view of a quantum rod light emitting display device according to a second modification of the first and second embodiments of the present invention; FIG.
10 is an enlarged view of the vicinity of a quantum rod layer in a quantum rod light emitting display device according to still another modification of the first and second embodiments of the present invention.

Hereinafter, a quantum rod light emitting display device according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

First, the quantum rod constituting the quantum rod layer which is the most characteristic constitution of the quantum rod light emitting device according to the present invention will be briefly described.

3 is a diagram showing a general form of a quantum rod.

As shown, the quantum rod 156 comprises a core 157 and a shell 158 surrounding the core 157. The quantum rod 156 may include a core 157 and a shell 158 surrounding the core 157. The quantum rod 156 may be omitted from the core 158. In this case, 157).

The core 157 may have a spherical shape, an elliptical shape, a polyhedron shape, or a rod shape, and the shape of the core 157 may be spherical.

On the other hand, when the quantum rod 156 is formed of only the core 157, the core 157 has an elliptical shape or a rod shape.

In addition, when the quantum rod 156 includes a shell 158 that surrounds the core 157, the core 157 may have any of spherical, ellipsoidal, polyhedral, and rod-like shapes, The cutter 158 has a rod shape with a long axis and a short axis. The cut surface cut in the minor axis direction of the quantum rod 156 can take any one of a circle, an ellipse, and a polygonal shape.

In addition, the shell 158 may have a single layer or a multilayer structure, and is formed of a material in which any one or a mixture of two or more materials selected from an alloy, an oxide-based material, or an impurity-doped material is mixed.

At this time, the shell 158 is characterized in that the ratio of the major axis to the minor axis has a range of 1: 1.1 to 1:30, so that the shell 158 can have various ratios.
In addition, the core 157, which is a component of the quantum rod 156 having such a configuration, may be a semiconductor, an alloy, or a mixture thereof of II-VI, III-V, III-VI, IV- &Lt; / RTI &gt;
When the core 157 of the quantum rod 156 is made of Group II-VI of the periodic table, any one of CdSe, CdS, CdTe, ZnO, ZnSe, ZnS, ZnTe, HgSe, HgTe, CdZnSe, CdSeTe and ZnCdSe Or a mixture of two or more substances.
In the case where the core 157 of the quantum rod 156 is made of Group III-V of the periodic table, the InP, InN, GaN, InSb, InAsP, InGaAs, GaAs, GaP, GaSb, AlP, AlN, AlAs, Any one material or a mixture of two or more materials may be used.
If the core 157 of the quantum rod 156 is made of a group VI-IV of the periodic table, it may be formed of any one material selected from the group consisting of PbSe, PbTe, PbS, PbSnTe and Ti ₂ SnTe ₅ , Lt; / RTI &gt;

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The material and the quantum rod 156 having a major axis to minor axis ratio are characterized in that the fluorescence wavelength is varied according to the size of the core 157 even though it is composed of the core 157 of the same material.

That is, as the size of the core 157 becomes smaller, it emits fluorescence of a shorter wavelength, and as the size becomes larger, fluorescence of a longer wavelength is generated.

Thus, the quantum rod is characterized in that it can nearly fluoresce the light of the desired visible region by adjusting the size of the core 157.

The quantum rod 156 made of the above-described material is formed on the core 157 itself or on the core 157 (as shown in FIG. 4 (the electron and the major state before and after the application of the electric field to the quantum rod) Is formed with a long axis and a short axis.

Therefore, before the electric field is applied in the long axis direction of the shell 158 or the core 157 having the long axis and the short axis, electrons and holes are coupled into the core 157, Electrons e and holes h are spatially separated in the core 157 or between the core 157 and the shell 158 when an electric field is applied in the longitudinal direction of the core 157 to induce separation of the band gap. The amount of light emitted or the amount of light emitted from the quantum rod 156 can be adjusted, so that light emitted from the quantum rod layer made of such a quantum rod can realize a gray level.

Here, the band gap refers to the highest energy level of the valence band, which is called the highest occupied molecular orbital (HOMO), and is called the lowest unoccupied molecular orbital (LUMO) at the lowest energy level of the conduction band , Which means energy difference between HOMO level and LUMO level.

Another characteristic of the quantum rod 156 having such a configuration is that its quantum yield is theoretically 100%, so that it can generate very high fluorescence.

 A sectional structure of a quantum rod light emitting device according to an embodiment of the present invention using the quantum rod having the above-described characteristics will be briefly described.

Hereinafter, a quantum rod light emitting device according to the present invention serving as a display device by providing a quantum rod having the above-described characteristics will be described.

5 and 6 are cross-sectional views of a quantum rod light emitting device according to the first and second embodiments of the present invention, respectively, showing three neighboring pixel regions, and only the pixel region P is a thin film transistor (Tr). Here, for convenience of description, a region where the thin film transistor is provided in each pixel region is defined as a switching region TrA. At this time, in the first and second embodiments of the present invention, only the arrangement direction of the plurality of quantum rods 156 provided in the quantum rod layer 155 is different, and the other components have the same configuration, The first embodiment will be mainly described, and the first and second embodiments will be described respectively only for the portions having different points.

The quantum rod light emitting device 101 according to the first embodiment of the present invention includes a first electrode 150 formed separately for each pixel region P and a second electrode 150 formed on the entire display region for displaying an image, A first substrate 110 having a first electrode 160 and a quantum rod layer 155 interposed between the first and second electrodes 150 and 160 and a second substrate 170 facing the first substrate A quantum rod panel 102 made up of a light source, and a backlight unit 180.

In the quantum rod light emitting display device 101 according to the first embodiment of the present invention having such a configuration, when the quantum rod layer 155 absorbs light emitted from the backlight unit 180, electrons and holes are recombined internally And the light is made to fluoresce.

At this time, the quantum rod light emitting display device 101 applies voltages to the first and second electrodes 150 and 160 located below and above the quantum rod layer 155, ) Of the quantum rod layer 155 by adjusting the recombination rates of electrons and holes in each of the plurality of quantum rods 156 constituting the quantum rod layer 155 to display the gray level, 155 can generate red, green and blue colors by forming the quantum rods 156 in different sizes for different pixel regions P emitting red, green and blue colors, so that full color images can be displayed.

First, in a quantum rod light emitting display device 101 according to an embodiment of the present invention having such a configuration, a first substrate (first substrate) 150 having the first and second electrodes 150 and 160 and a quantum rod layer 155 110 will be described.

For example, aluminum (Al), an aluminum alloy (AlNd), copper (Al), or the like, having low resistance characteristics, on the first substrate 110 made of a transparent insulating substrate such as a transparent glass substrate or a flexible substrate. (Not shown) extending in the first direction are formed of one or more materials selected from the group consisting of copper (Cu), copper alloy, molybdenum (Mo), and molybdenum alloy (MoTi).

A gate electrode 108 is formed in the switching region TrA in each pixel region P above the first substrate 110 and connected to the gate wiring (not shown).

An inorganic insulating material such as silicon oxide (SiO ₂ ) or silicon nitride (SiNx) is formed on the entire surface of the first substrate 110 over the gate wiring (not shown) and the gate electrode 108, Respectively.

In the switching region TrA above the gate insulating film 115, an active layer 120a of pure amorphous silicon and an upper portion of the active layer 120a are formed corresponding to the gate electrode 108, A source electrode 133 and a drain electrode 136 which are spaced apart from each other and which are in contact with the ohmic contact layer 120b are formed on the semiconductor layer 120, Respectively. At this time, the active layer 120a is exposed between the source electrode 133 and the drain electrode 136 which are spaced apart from each other.

The gate electrode 108, the gate insulating film 115, the semiconductor layer 120, the source electrode 133, and the drain electrode (not shown) sequentially stacked in the switching region TrA provided in each pixel region P 136 constitute a thin film transistor Tr.

A data line 130 intersecting the gate line (not shown) and defining the pixel region P extends in the second direction and is connected to the source electrode (not shown) of the thin film transistor Tr 133, respectively.

At this time, a dummy pattern 121 composed of the first and second semiconductor patterns 121a and 121b is formed under the data line 130 using the same material as the active layer 120a and the ohmic contact layer 120b However, this is an example of the manufacturing process, and the dummy pattern 121 may be omitted.

In the figure, the thin film transistor Tr includes an active layer 120a made of amorphous silicon and a semiconductor layer 120 of the ohmic contact layer 120b, and a bottom electrode (gate electrode) Type bottom gate type. However, it is also possible to provide a polysilicon semiconductor layer, a gate insulating film, a gate electrode, and a semiconductor layer contact hole for exposing the semiconductor layer by providing a semiconductor layer made of polysilicon A top gate type having a structure in which an interlayer insulating film and source and drain electrodes which are in contact with the semiconductor layer of polysilicon through the semiconductor layer contact holes and are spaced apart from each other are sequentially layered.

When a top gate type thin film transistor having the above-described structure is provided, the gate wiring (not shown) is provided on the gate insulating film on which the gate electrode is formed, and the data wiring is provided on the interlayer insulating film.

Next, a protective layer 140 having a flat surface is formed on the data line 130 and the source and drain electrodes 133 and 136. A drain contact hole 143 is formed in the passivation layer 140 to expose the drain electrode 136 of each thin film transistor Tr for each pixel region P.

A first electrode (not shown) is formed on the passivation layer 140 and is in contact with the drain electrode 136 of the thin film transistor Tr through the drain contact hole 143 in each pixel region P 150 are formed.

A gate line (not shown) and a gate line (not shown) are formed on the first electrode 150 and the protective layer 140 exposed between the first electrode 150 and the data line 130 A buffer pattern 152 is formed to overlap the edge of the first electrode 150.

A quantum rod layer 155 formed of a plurality of quantum rods 156 is formed on the first electrode 150 in each pixel region P surrounded by the buffer pattern 152.

At this time, the quantum rod layer 155 may be provided with a quantum rod 156 having cores (157 of FIG. 3) of different sizes for each pixel region P emitting red, green, and blue, A quantum rod 156 having the same size core (157 in FIG. 3) may be provided.

When the quantum rod layer 155 is provided as the quantum rod 156 having the same size core (157 in FIG. 3) in the entire display region, the second substrate 170 is provided with the quantum rod layer 155 A color filter layer (not shown) having a shape in which red, green, and blue color filter patterns are sequentially repeated is provided.

In the quantum rod light emitting display device 101 according to the first and second embodiments of the present invention, in the case of the first embodiment, the quantum rod layer 155 has a plurality of The quantum rods 156 of the first substrate 110 are arranged in one direction in parallel with the surface of the first substrate 110 on the entire surface of the display region of the first substrate 110, The plurality of quantum rods 156 are arranged on the first substrate 110 in a state where the major axes are perpendicular to the first substrate 110.

The degree to which the long axes of the quantum rods 156 are well aligned in one direction, that is, the degree of orderliness, can be determined by measuring the polarization ratio. That is, the polarization ratio of the quantum rod layer 155 can be determined by irradiating the horizontally or vertically polarized light toward the quantum rod layer 155 and measuring the amount of light passing through the photomask (not shown).

When the light intensity from the light source (not shown) is I, the light with only the horizontal component is I _h , and the light with only the vertical component is I _v , if the directionality of the quantum rod 156 is not normally given , And the polarization ratio (PR)

PR = (I _h - I _v ) / (I _h + I _v ).

The plurality of quantum rods 156 in the quantum rod layer 155 are arranged in a single direction, that is, horizontally aligned on the first substrate 110. In this case, When arranged in the horizontal or vertical direction with respect to a virtual reference axis, the polarization ratios PR _h and PR _v in the horizontal and vertical directions are respectively defined as follows.

PR _h = I _h / (I _h + I _v ),

PR _v = I _v / (I _h + I _v )

The reason why the plurality of quantum rods 156 in the quantum rod layer 155 are well aligned in one direction is that the polarization ratio PR _h in the horizontal direction or the polarization ratio PR _v in the vertical direction is larger than 0.5 and smaller than 1 That is, 0.5 <PR _h or PR _v <1.

When a plurality of quantum rods 156 are arranged horizontally with respect to the surface of the first substrate 110 as in the first embodiment, the long axes of the quantum rods 156 may be arranged in one direction Or the long axis perpendicular to the surface of the first substrate 110, as in the second embodiment, absorbs the light emitted from the backlight unit 180 more effectively, thereby allowing a larger amount of fluorescence, To improve the characteristics, and further to realize low power consumption while having high brightness characteristics.

As shown in FIG. 7 (a diagram schematically showing only the first substrate and the quantum rod in the quantum rod light emitting device according to the first embodiment of the present invention), the quantum rod layer (FIG. 5 The plurality of quantum rods 156 arranged in the first substrate 110 and the plurality of quantum rods 156 disposed in the first substrate 110 are parallel to the first substrate 110, 110) plane.

On the other hand, FIG. 8 (a cross-sectional view schematically showing only the first substrate and the quantum rod in the quantum rod light emitting display device according to the comparative example in which the quantum rods are arranged so as to form a tilt angle larger than 0 degrees with the first substrate surface as a comparative example) The quantum rod 256 arranged so as to form a tilt angle? Greater than 0 degrees with respect to the surface of the first substrate 210 has an area projected on the first substrate surface 210 is larger than that of the quantum rod shown in FIG. It can be seen that a small area is provided in comparison with the quantum rod light emitting device (101 of FIG. 5) according to the first embodiment of the present invention which is disposed in parallel to the first substrate surface 110.

5, when the light emitted from the backlight unit 180 passes through the first substrate 110 and is incident into the quantum rod layer 155, the light is incident on each quantum rod 156 Since the amount of light is maximized, the absorption rate of light for each quantum rod 156 is maximized, so that the fluorescence effect of each quantum rod 156 can be maximized, so that transmission and luminance characteristics can be improved.

When the quantum rod 156 is disposed on the first substrate 110 so as to be parallel to the surface of the first substrate 110 so that the area of the quantum rod 156 is maximized when the first substrate 110 is projected on the characteristic of the quantum rod 156, The rate can also be improved.

In comparison with the quantum dot light emitting display device using the quantum dot as another comparative example, when the size of the core is the same on the characteristic of the quantum rod 156, the area for receiving light is broader than the quantum dot having the spherical shape, Since the quantum rod 156 is arranged so as to be parallel to the surface of the first substrate 110 in order to maximize the light receiving area as in the first embodiment of the present invention, the recombination rate of holes and electrons It can be seen that it increases remarkably.

Further, it can be seen that the recombination rate of holes and electrons remarkably increases compared with the comparative example (see FIG. 8) in which the tilt angle is set to be larger than 0 degree, which is not parallel to the plane of the first substrate 110, have.

In the quantum rod light emitting display element 101 (FIG. 5) and the comparative example quantum dot light emitting display element (not shown), the recombination of holes and electrons does not proceed in the quantum rod layer 155 itself, ) And a quantum dot (not shown), so that light is recombined with holes and electrons in response to light incident on each quantum rod 156.

Accordingly, the quantum rod 156 compared to the quantum dot (not shown) having a spherical shape has much better recombination rate of holes and electrons, and even if the quantum rod 156 of the same size is parallel to the first substrate 110 And it is found that the first embodiment of the present invention in which the long axes thereof are arranged in one direction has an excellent effect in terms of the highest recombination rate.

It is obvious that the recombination rate of holes and electrons is high, and the luminance characteristic is improved because the efficiency of fluorescence increases.

6, in the case of the quantum rod light emitting device 101 according to the second embodiment of the present invention, the quantum rod 156 provided in the quantum rod layer 155 is formed on the surface of the first substrate 110 And also in the case of having such a configuration, the light absorption rate is maximized, and the luminance characteristic can be improved.

When the quantum rods 156 are arranged perpendicular to the surface of the first substrate 110, the density of the quantum rods 156 per unit area is the largest, and the mobility in the long axis direction of the quantum rods 156 is larger than the mobility in the short axis direction Big.

Therefore, when the longitudinal axes of the plurality of quantum rods 156 are arranged perpendicular to the surface of the first substrate 110 such that the plurality of quantum rods 156 have a large density per unit area as in the second embodiment of the present invention, Since the recombination time of electrons and holes is increased, the recombination rate per unit time is improved, thereby improving the luminance characteristic and a relatively large number of quantum rods per unit area can be arranged, Can be improved.

5 and 6, a plurality of quantum rods 156 may be arranged in the quantum rod layer 155 in one direction parallel to the first substrate 110, ) Plane. The alignment method is, for example, a voltage application method, an orientation method using an alignment film, an alignment method using a self-aligned monomer, or an alignment method using a reactive mesogenic material. In this case, the alignment method is mentioned as an example. In addition to the four alignment methods mentioned above, the quantum rod 156 can be oriented in one direction by various alignment methods.

On the other hand, when the quantum rod 156 having the cores (157 in FIG. 3) having different sizes is provided for each pixel region P representing the red, green and blue colors, the quantum rod 156, The wavelength of the fluorescent light is changed according to the size of the core (157 in FIG. 3). The shorter the size of the core (157 in FIG. 3), the shorter wavelength fluorescence is generated.

Accordingly, in this case, it is necessary to form the quantum rod layer 155a having the largest core (157 in FIG. 3) size (diameter) corresponding to the pixel region P which should exhibit red, and to display green and blue A quantum rod (156 in FIG. 3) having a size smaller than the size of the core (157 in FIG. 3) of the quantum rod (156 in FIG. 3) provided in the pixel region (P) The quantum rod layers 155b and 155c are formed.

In the first and second embodiments of the present invention shown in FIGS. 5 and 6, the quantum rod layer 155 is formed separately for each pixel region P, The quantum rod layer 155 is a display region in which a plurality of pixel regions P are provided, as shown in the sectional view of the quantum rod light emitting display device according to the first modification of the first and second embodiments of the present invention) In this case, the buffer pattern 152 provided at the boundary between the pixel regions P is omitted.

Referring to FIGS. 5 and 6, the first and second embodiments of the present invention include a second substrate 170 corresponding to the first substrate 110 having such a configuration, The substrate 170 may be a transparent insulating substrate such as the first substrate 110, or may be made of a glass material or a plastic material having a flexible property, or may be a sheet or a film made of a polymer material.

On the inner surface of the second substrate 170, a black matrix 173 is formed to correspond to the boundary of the pixel region P and the portion where the thin film transistor Tr is formed.

The black matrix 173 must be provided to prevent light leakage when the quantum rod layer 155 is formed on the entire display region (see FIG. 9A). The quantum rod layer 155 may be formed in each pixel region P) may be omitted.

In the first and second embodiments of the present invention, only the black matrix 173 is provided on the inner surface of the second substrate 170. However, when the quantum rod layer 155 is provided in each pixel region P (156 in Fig. 3) having a core (157 in Fig. 3) having the same size as the quantum rod (156 in Fig. 3) (A sectional view of the display device), for the purpose of full color implementation, the red, green and blue colors are sequentially and repeatedly applied to three neighboring pixel regions P corresponding to the region surrounded by the black matrix 173 And the color filter layer 155 corresponding to the blue color filter patterns 175a, 175b, and 175c may be provided.

Although not shown, an overcoat layer (not shown) may be provided on the entire surface of the second substrate 170 above the black matrix 173 and the color filter layer 155.

5 and 6, the quantum rod layer 155 provided on the first substrate 110 has a different size for each pixel region P that should exhibit red, green, and blue colors, The color filter layer (not shown) provided on the second substrate 170 may be omitted for realizing the high luminance characteristic, or alternatively, the quantum rod 156 may be omitted in FIG. 9B It may be provided for realizing a better color reproduction rate as in the second modification shown in the figure.

In the first and second embodiments of the present invention and modifications thereof, it is shown that only the quantum rod layer 155 is provided between the first electrode 150 and the second electrode 160, (The enlarged view of the vicinity of the quantum rod layer in the quantum rod light emitting display device according to another modification of the first and second embodiments of the present invention), the first electrode 150 and the quantum rod layer An electron injection layer 158 may be further provided between the quantum rod layer 155 and the second electrode 160 as a fluorescent auxiliary layer, .

5 and 6, a backlight unit (not shown) for supplying light to the quantum rod layer 155 is formed on the lower surface of the quantum rod panel 102 having such a configuration, more precisely on the outer surface of the first substrate 110, (Not shown).

The backlight unit 180 includes a light source 182, a reflection plate 185, a light guide plate 187 placed on the reflection plate 185, and a plurality of optical sheets 190 disposed on the light guide plate 187, .

In this case, the light source 182 generates light of a short wavelength range, for example, blue visible light or UV light, which is smaller than 450 nm in the characteristics of the present invention. The CCFL (cold cathode fluorescent lamp) ) Or a light emit diode (LED), and in the drawing, the fluorescent lamp is shown as an example.

The light source 182 is positioned at one side of the light guide plate 187 so as to face the light incident portion of the light guide plate 187. When the light source 182 is a fluorescent lamp, the lamp guide (not shown) .

The light guide plate 187 spreads the light incident from the light source 182 evenly into the light guide plate 187 while advancing the light through the light guide 182 several times, .

At this time, the light guide plate 187 may include a pattern (not shown) having a specific shape on the back surface to supply a uniform surface light source to the quantum rod panel 102.

In order to guide the light incident into the light guide plate 187, a pattern (not shown) of a specific shape may be formed of an elliptical pattern, a polygon pattern, a hologram pattern, And such a pattern is formed on the lower surface of the light guide plate 187 by a printing method or an injection method.

The reflection plate 185 is disposed on the back surface of the light guide plate 187 and reflects the light that has passed through the back surface of the light guide plate 187 toward the quantum rod panel 102 to improve the brightness of light.

The optical sheet 190 provided on the light guide plate 187 includes a diffusion sheet 188 and at least one light condensing sheet 189.

The backlight unit 180 having such a configuration is an edge type in which the light source 182 is provided on the side surface of the light guide plate 187 and the surface light source is incident on the quantum rod panel 102 by the light guide plate 187 However, the backlight unit 180 may be a direct-type type.

Although not shown in the drawing, a direct drive type backlight unit (not shown) is provided with a driving substrate for LEDs in which fluorescent lamps are arranged as a plurality of light sources at regular intervals or on which a plurality of LEDs are arranged, And a diffusion plate is provided on the top of the light guide plate in place of the light guide plate, and a plurality of optical sheets are provided on the diffusion plate.

Since the quantum rod light emitting display device 101 according to the first and second embodiments or modifications thereof having such a configuration does not require a polarizing plate for lowering the luminance characteristic, the brightness characteristic is lowered by the provision of the polarizing plate There is an advantage that a high luminance characteristic and a low power consumption characteristic compared with a liquid crystal display device in which power consumption is increased by providing a brighter light source to improve the lowered luminance characteristic.

The quantum rod 156 disposed in the quantum rod layer 155 may be arranged in parallel with the first substrate 110 and may have a configuration in which the long axes thereof are oriented in one direction, And maximize the recombination rate per unit time, the light emitted from the backlight unit 180 is absorbed and fluoresced more efficiently, The luminance characteristics and the low power consumption characteristics of the quantum rod light emitting display device compared to the quantum dot light emitting display device or the quantum rod light emitting display device in which the quantum rods are arranged in disorder are improved.

In addition, since the quantum rod display device 101 according to the first and second and third embodiments of the present invention does not require a polarizing plate or the like and further can omit a color filter layer, It is possible to reduce the number of parts, thereby reducing the manufacturing cost.

The present invention is not limited to the above-described embodiments, and various changes and modifications may be made without departing from the spirit of the present invention.

101: Quantum rod light emission display device 102: Quantum rod panel
110: first substrate 108: gate electrode
115: gate insulating film 120: semiconductor layer
120a: active layer 120b: ohmic contact layer
121: dummy patterns 121a and 121b: first and second dummy patterns
130: data line 133: source electrode
136: drain electrode 140: protective layer
143: drain contact hole 150: first electrode
152: buffer pattern 155: quantum road layer
155a, 155b, and 155c: quantum rod layers that fluoresce red, green, and blue, respectively
160: second electrode 170: second substrate
173: Black matrix 180: Backlight unit
182: light source 183: lamp guide
185: reflector 187: light guide plate
188: diffusion sheet 188: condensing sheet
190: optical sheet P: pixel area
Tr: thin film transistor TrA: switching region

Claims (19)

A first substrate on which a plurality of pixel regions are defined;
A first electrode formed on the first substrate for each pixel region;
A plurality of quantum rods formed on the first electrode and having a plurality of quantum rods oriented in one direction in parallel with one surface of the first substrate or a plurality of quantum rods oriented perpendicularly to one surface of the first substrate A quantum rod layer;
A second electrode formed on the quantum rod layer;
A second substrate facing the first substrate;
A backlight unit provided on an outer surface of the first substrate,
/ RTI &gt;
Wherein the quantum rod comprises a core comprising electrons and holes,
The electrons and the holes may be coupled to or separated from each other depending on the presence or absence of an electric field formed by the first and second electrodes,
Wherein the light emitted from the backlight unit is controlled in the amount of light and / or the amount of light emission in the quantum rod layer.
The method according to claim 1,
The pixel region is divided into first, second, and third pixel regions that emit red, green, and blue, respectively,
Wherein the quantum rod layer is formed by patterning the first, second, and third pixel regions,
Wherein the quantum rod layer comprises the quantum rods having the cores of different sizes for the first, second and third pixel regions.
3. The method of claim 2,
And the second substrate is provided with red, green, and blue color filter patterns corresponding to the first, second, and third pixel regions, respectively.
The method according to claim 1,
The pixel region is divided into first, second, and third pixel regions that emit red, green, and blue, respectively,
Wherein the quantum rod layer is disposed on a front surface of the first substrate including the first electrode without distinguishing between the first, second, and third pixel regions.
5. The method of claim 4,
Wherein the quantum rod layer comprises the quantum rods including the cores of the same size in each of the first, second and third pixel regions,
Wherein the second substrate is provided with red, green, and blue color filter patterns corresponding to the first, second, and third pixel regions, respectively.
◈ Claim 6 is abandoned due to the registration fee. The method according to claim 1,
A gate line and a data line crossing the first substrate to define the pixel regions;
Wherein the first electrode is connected to the drain electrode of the thin film transistor, and the first electrode is connected to the drain electrode of the thin film transistor.
The method according to claim 1,
The plurality of quantum rods are oriented in one direction in parallel with one surface of the first substrate,
The polarization ratio PR _h in the horizontal direction and the polarization ratio PR _v in the vertical direction of the first reference line are expressed as PR _h = I _h / (I _{h + I v), PR v =} I v / (I h + I v) when defined as, i.e., has a smaller value than the polarization ratio PR _v is greater than 0.5 1 of the polarization ratio PR _h or the direction perpendicular to the horizontal direction , And 0.5 < PR _h (or PR _v ) < 1.
The method according to claim 1,
The quantum rod includes:
The core is made of only the core,
Or a shell surrounding the core and the core,
Wherein the shell has a shape having a minor axis and a major axis, and a ratio of the minor axis to the major axis is 1: 1.1 to 1:30.
◈ Claim 9 is abandoned upon payment of registration fee. 9. The method of claim 8,
Wherein the core of the quantum rod has one of a spherical shape, an elliptical shape, a polyhedral shape, and a rod shape,
Wherein the cut surface of the quantum rod cut in the minor axis direction has a shape of a circle, an ellipse, or a polygonal shape.
◈ Claim 10 is abandoned due to the registration fee. 10. The method of claim 9,
Wherein the shell comprises a single layer or a multi-layer structure.
◈ Claim 11 is abandoned due to registration fee. 11. The method of claim 10,
Wherein the shell is made of an alloy, an oxide-based material, or an impurity-doped material.
◈ Claim 12 is abandoned due to registration fee. 9. The method of claim 8,
Wherein the core is made of a semiconductor, an alloy, or a mixed material of group II-VI, III-V, III-VI, IV-VI and IV in the periodic table.
◈ Claim 13 is abandoned due to registration fee. 13. The method of claim 12,
The core of the quantum rod may be made of any one of CdSe, CdS, CdTe, ZnO, ZnSe, ZnSe, HgSe, HgTe, CdZnSe, CdSeTe, ZnCdSe, &Lt; / RTI &gt;
In the case of the III-V group, the second electrode is made of any one material selected from the group consisting of InP, InN, GaN, InSb, InAsP, InGaAs, GaAs, GaP, GaSb, AlP, AlN, AlAs and AlSb,
If made of a Ⅵ-Ⅳ group, PbSe, PbTe, PbS, PbSnTe , Ti 2 SnTe 5 by any one of or made or is characterized by a quantum rod-luminescence display device consisting of two or more materials are mixed material.
The method according to claim 1,
Wherein the backlight unit generates blue or ultraviolet light having a short wavelength of 430 nm or less.
◈ Claim 15 is abandoned due to registration fee. The method according to claim 1,
The backlight unit includes:
An edge type backlight unit including a reflective plate, a light guide plate disposed on the reflective plate, a light source positioned on a side surface of the light guide plate, and a plurality of optical sheets positioned on the light guide plate,
Or a direct-type backlight unit comprising a reflection plate, a light source positioned above the reflection plate, a diffusion plate located above the light source, and a plurality of optical sheets located on the diffusion plate.
3. The method of claim 2,
Wherein the quantum rod layer positioned corresponding to the first pixel region has a first size of the core,
Wherein the quantum rod layer positioned corresponding to the second pixel region has a second size smaller than the first size,
And the quantum rod layer located corresponding to the third pixel region has a third size where the core is smaller than the second size.
The method according to claim 1,
The quantum rod oriented perpendicularly to one surface of the first substrate
Wherein a density per unit area of the quantum rod is greater than that of the quantum rod oriented parallel to one surface of the first substrate.
The method according to claim 1,
The light emitted from the backlight unit is absorbed by the quantum rod layer to couple the electrons and the holes,
Wherein a coupling ratio of the electron and the hole is varied according to the intensity of the electric field.
3. The method of claim 2,
And a buffer pattern is provided at the boundaries of the first, second, and third pixel regions.

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