KR101937824B1 - Organic light emitting device - Google Patents

Abstract

An organic light emitting device according to an embodiment includes: an organic light emitting element that outputs light; A light extracting film formed on the organic light emitting element; And an adhesive layer interposed between the light extracting film and the organic light emitting device to bond the organic light emitting device and the light extracting film.

Description

[0001] The present invention relates to an organic light emitting device,

An embodiment relates to an organic light emitting device.

[0002] An organic light emitting diode (OLED) display is a self-emission type display device having an organic light emitting diode that emits light and displays an image. Unlike a liquid crystal display, an organic light emitting display does not require a separate light source, so that the thickness and weight can be relatively reduced. In addition, organic light emitting display devices are attracting attention as next generation display devices for portable electronic devices because they exhibit high quality characteristics such as low power consumption, high luminance, and high response speed.

The OLED display includes a cathode electrode, an anode electrode, and an organic emission layer interposed between the cathode electrode and the anode electrode. When a voltage is applied to both the cathode electrode and the anode electrode, electrons and holes are injected from the cathode electrode and the anode electrode, respectively, and light is generated due to energy generated when the excitons formed by coupling in the organic light emitting layer drop to the ground state. The light emitted from the organic light emitting layer is reflected by the internal structure due to the difference in refractive index between the internal structures. As a result, a considerable amount of light is lost in the internal structure, resulting in low light extraction efficiency. In addition, since the optical paths are different, efficiency of each of red, green, and blue is different, and the wavelength is distorted, so that light having a desired wavelength can not be output.

The embodiment provides an organic light emitting device capable of improving light efficiency and outputting light of a uniform wavelength band.

An organic light emitting device according to an embodiment includes: an organic light emitting element that outputs light; A light extracting film formed on the organic light emitting element; And an adhesive layer interposed between the light extracting film and the organic light emitting device to bond the organic light emitting device and the light extracting film.

The adhesive layer may be a polymer material including an adhesive material, and the light extracting film may be attached to the adhesive layer after the adhesive layer is attached to the organic light emitting device.

The adhesive material may be OCA or PDMS.

The organic light emitting device includes a substrate, and a difference in refractive index between the substrate and the adhesive layer may be 5% or less.

The light extracting film may include a plurality of beads.

The beads may be acrylic beads, and the acrylic beads may have a size of 4 um to 20 um.

The beads are glass beads, and the glass beads may have a size of 50 nm to 2000 um.

The thickness of the light extracting film may be 50 [mu] m to 300 [mu] m.

The beads may have a concentration of 30% to 70%.

And a quantum dot film attached on the light extracting film.

And a quantum dot film formed between the light extracting film and the organic light emitting device.

The light extracting film may include a plurality of quantum dots and a plurality of beads.

The light extracting film incorporating the plurality of quantum dots and the plurality of beads may have a thickness of 150 to 1000 um.

The light extracting film incorporating the plurality of quantum dots and the plurality of beads may have a thickness of 150 to 1000 um.

The light extracting film may further include a first light extracting film and a second light extracting film, and a quantum dot film interposed between the first light extracting film and the second light extracting film.

The organic light emitting device according to the embodiment can improve the light efficiency by bonding the light extracting film to the adhesive layer having a refractive index within a certain range.

The organic light emitting device according to the embodiment can improve light efficiency by incorporating beads having a certain size range into a light extracting film.

The organic light emitting device according to the embodiment can further attach a quantum dot film to improve light efficiency and output light of a uniform wavelength band.

The organic light emitting device according to the embodiment can improve light efficiency and output light of a uniform wavelength band by attaching a light extracting film incorporating a plurality of quantum dots and a plurality of beads.

1 is a view showing an organic light emitting device according to a first embodiment.
2 is a graph showing the rate of increase in optical efficiency according to the thickness of the light extracting film.
3 is a view showing an organic light emitting device according to a second embodiment.
4 is a view showing an organic light emitting device according to the third embodiment.
5 is a diagram showing the light efficiency of the organic light emitting device of the first to third embodiments.
6 is a view showing an organic light emitting device according to a fourth embodiment.
FIG. 7 is a graph showing the intensity of light output from the organic light emitting device according to the fourth embodiment by wavelength.
FIG. 8 is a graph showing the intensity of light with respect to wavelength according to the thickness of the mixed film of the organic light emitting device according to the fourth embodiment.

Hereinafter, specific embodiments of the present invention will be described in detail with reference to the drawings. It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the inventive concept. Other embodiments falling within the scope of the inventive concept may readily be suggested, but are also considered to be within the scope of the present invention.

The same reference numerals are used to designate the same components in the same reference numerals in the drawings of the embodiments.

1 is a view showing an organic light emitting device according to a first embodiment.

Referring to FIG. 1, the organic light emitting device 1 according to the first embodiment may include an organic light emitting device 10, a light extracting film 20, and an adhesive layer 30.

The organic light emitting device 10 may include a first electrode 11, an organic light emitting layer 13, a second electrode 15, and a substrate 17.

The first electrode 11 may be an anode electrode or a cathode electrode. If the first electrode 11 is an anode electrode, the second electrode 15 may operate as a cathode electrode. If the first electrode 11 is a cathode electrode, the second electrode 15 may be an anode electrode Lt; / RTI >

The first electrode 11 may be formed of an alloy or a laminate of a metal having a low work function and containing a high work function including Ag, Mg, Al, Pt, Au, Ni, Nd, Ir, Cr, Li and Ca. A metal having a low work function is used for the first electrode 11 to lower a barrier formed between the first electrode 11 and the organic light emitting layer 13 to facilitate electron injection to secure a high current density .

The second electrode 15 may be formed of a transparent conductive material so as to transmit light from the organic light emitting layer 13. The second electrode 15 may be formed of ITO, ITZO, or IZO material. The second electrode 15 may be formed of a nanowire, a metal mesh, a nanotube, or a graphene.

The organic light emitting layer 13 may be formed between the first electrode 11 and the second electrode 15. The organic light emitting layer 13 may be formed of multiple layers including at least one of a hole injection layer, a hole transport layer, a light emitting layer, an electron transport layer, and an electron injection layer. Among the above-mentioned layers, the remaining layers except for the light emitting layer may be omitted in some cases.

When the organic light emitting layer 13 includes all the layers described above, the hole injection layer is disposed in a region in contact with the anode electrode, the electron injection layer is disposed in a region in contact with the cathode electrode, A hole transporting layer, a light emitting layer and an electron transporting layer may be sequentially stacked on the injection layer. The organic light emitting layer 13 may further include another layer as needed.

The substrate 17 may be positioned on the second electrode 15. The substrate 17 may serve as a base of the organic light emitting diode 10. Although the substrate 17 is stacked on the second electrode 15 in the drawing, the second electrode 15, the organic light emitting layer 13, and the first electrode 11 ) May be sequentially stacked to form the organic light emitting element 10.

The substrate 17 may comprise a glass or plastic material. The substrate 17 may be formed of a flexible substrate. When the substrate 17 is a glass substrate, the substrate 17 may have a refractive index of 1.48.

The light extracting film 20 may be attached to the organic light emitting device 10. The light extracting film 20 may be attached to the organic light emitting device 10 by the adhesive layer 30. The light extracting film 20 may be attached to the substrate 17 of the organic light emitting device 10. The light extracting film 20 may be attached to the substrate 17 through the adhesive layer 30. That is, the second electrode 15 may be formed on one surface of the substrate 17, and the adhesive layer 30 may be attached to the other surface of the substrate 17. The adhesive layer 30 may be applied to the front surface of the substrate 17 and adhered to the front surface of the light extracting film 20. Both surfaces of the adhesive layer 30 may have adhesiveness.

The light extracting film 20 may be adhered on the adhesive layer 30 after the adhesive layer 30 is adhered on the substrate 17. That is, the light extracting film 20 may be attached on the adhesive layer 30 after the adhesive layer 30 is attached on the substrate 17.

After the adhesive layer 30 is adhered on the substrate 17, pressure is applied to remove the gap that may exist between the adhesive layer 30 and the substrate 17, and then the light extracting film 20 is adhered to the adhesive layer 30 30 and then applying a pressure on the light extracting film 20 to remove a gap that may exist between the light extracting film 20 and the adhesive layer 30.

The adhesive layer 30 may have a refractive index. The refractive index of the adhesive layer 30 may be the same as that of the substrate 17. Alternatively, the adhesive layer 30 may have a refractive index within an error range with respect to the substrate 17. The error range of the refractive index between the adhesive layer 30 and the substrate 17 may be 5% or less based on the refractive index of the substrate 17.

The adhesive layer 30 may be formed of a polymer material including an adhesive material. The adhesive layer 30 may be formed of PDMS or OCA material. When the adhesive layer 30 is formed of PDMS or OCA material, the total area of the light extracting film 20 is smaller than the total area of the light extracting film 20, Can be uniformly adhered to the substrate (17), thereby reducing light loss caused by a difference in refractive index depending on a gap between the light extracting film (20) and the substrate (17).

When the adhesive layer 30 is formed of PDMS material, the refractive index of the adhesive layer 30 may be 1.45. When the adhesive layer 30 is formed of an OCA material, the refractive index of the adhesive layer 30 may be 1.475.

division Conventional Conventional attachment method Adhesion using PDMS Adhesion using OCA Luminous efficiency (lm / W) 31.6 43.08 46.36 49.37 Increase in optical efficiency (%) 100 136.3 146.7 156.2

Table 1 is a table showing the light efficiency to be increased when the adhesive layer 30 is used for bonding.

Table 1 shows that the light efficiency of the organic light emitting device without the conventional light extracting film 20 is 31.6 lm / W and the light efficiency of the organic light emitting device with the light extracting film 20 using the conventional adhesive tape is 43.08 lm / W, the optical efficiency of the organic light emitting device is 43.46 lm / W when the light extracting film 20 is attached using the PDMS. The light efficiency of the organic light emitting device is 46.7% higher than that of the conventional organic light emitting device. In addition, it can have a higher optical efficiency than the conventional method using an adhesive tape.

When the light extracting film 20 is attached using the OCA, the light efficiency of the organic light emitting device is 49.37 lm / W, which is 56.2% higher than the light efficiency of the conventional organic light emitting device. Light efficiency can be obtained.

That is, in the case of attaching the light extracting film 20 using the PDMS or OCA adhesive layer 30, the light efficiency is remarkably improved as compared with the organic light emitting device not using the conventional light extracting film 20, It is possible to have a higher optical efficiency than the method using an adhesive tape. Therefore, by attaching the light extracting film 20 using the PDMS or OCA adhesive layer 30, the power consumption can be reduced and the brightness can be improved.

In addition, when the light extracting film 20 is adhered using the adhesive layer 30, it can be seen from Table 2 that light output at a whole wavelength range is output.

Light source Blue light source Red light source Green light source Conventional (lm / w) 1.81 1.19 17.95 Adhesion using OCA (lm / w) 2.48 1.74 28.9 Increase in optical efficiency (%) 137 146.2 161

In the case of attaching to the organic light emitting device 10 that outputs light having a wavelength band of each of the light extracting films 20 using the adhesive layer 30 of OCA material, the organic light emitting device 10 ) Has a luminous efficiency increase rate of 37%, a luminous efficiency increase rate of 46.2% for the organic light emitting element 10 that outputs red light, and a luminous efficiency increase rate of 61% for the organic light emitting element 10 that outputs green light can confirm.

When the light extracting film 20 is adhered using the adhesive layer 30, a high light efficiency rise can be caused in the propagation zone, thereby causing an increase in the light efficiency of the white light caused by superposition of blue, red and green wavelength ranges There is an effect that can be.

The light extracting film 20 may include a plurality of beads. The plurality of beads may be uniformly distributed within the light extracting film 20. [

The beads may be acrylic beads or glass beads. The acrylic beads may have a size of 4 um to 20 um. The acrylic beads may have a refractive index of 1.49.

Table 3 shows the rate of optical efficiency increase depending on the size of the acrylic beads. At this time, the concentration of the acrylic beads was fixed to 30%.

Conventional 4um 20um Light efficiency (lm / w) 4.92 6.46 6.37 Increase in optical efficiency (%) 100 131.3 129.5

Referring to Table 3, when 4 μm acrylic beads are used, light efficiency of 31.3% can be obtained higher than when acrylic beads are not used, and 29.5% higher light efficiency can be obtained when using 20 μm acrylic beads.

The glass beads may have a size of 50 nm to 2000 um. The glass beads may have a refractive index of 1.36 to 1.44.

Table 4 shows the rate of optical efficiency increase according to the size of the glass beads. At this time, the concentration of the glass beads was fixed at 30%.

Conventional 50nm 500 nm 2000 nm Luminous efficiency (lm / W) 4.92 6.98 6.36 6.5 Increase in optical efficiency (%) 100 145.7 129.3 132.1

Referring to Table 4, when using 50 nm glass beads, light efficiency of 45.7% higher than when glass beads are not used, 29.3% higher light efficiency when using glass beads of 500 nm, If glass beads are used, a high optical efficiency of 32.1% can be obtained.

When the beads smaller than the above range are used, the light reflected on the beads is small, so that the effect of increasing the light efficiency can not be obtained. When the beads larger than the above range are used, the light efficiency increase effect can not be obtained due to the decrease of the transmittance.

When the light extracting film 20 includes acrylic beads or glass beads as described above, the light efficiency can be improved.

The light extracting film 20 may cause a high optical efficiency rise at a thickness within a certain range. The thickness of the light extracting film 20 may be 50 [mu] m to 300 [mu] m.

2 is a graph showing the rate of increase in optical efficiency according to the thickness of the light extracting film.

2A and 2B, the light extracting film 20 may have a light efficiency of 5.55 lm / W when the thickness of the light extracting film 20 is 50um and a light efficiency of 5.79 lm / W when the thickness of the light extracting film 20 is 100um. The light extraction efficiency of the light extracting film 20 may be as high as 6.05 lm / W when the thickness of the light extracting film 20 is 200 mum and the light efficiency of 6.98 lm / W when the thickness of the light extracting film 20 is 300 mum Lt; / RTI >

In addition, when the thickness of the light extracting film 20 is in the range of 50 袖 m to 300 袖 m, the light efficiency may be evenly increased in the waveguide.

If the thickness of the light extracting film 20 is less than 20 탆, a large cost is incurred in the manufacturing process and a high optical efficiency rise can not be caused. If the thickness of the light extracting film 20 is more than 300 탆, the thickness of the light extracting film 20 may not be sufficient to meet the requirement for a thin display device.

Further, the beads of the light extracting film 20 may cause a high optical efficiency rise at a concentration within a certain range. The glass beads may have a concentration of 30% to 70%. The concentration of the glass beads may be defined as the volume of the entire glass beads with respect to the volume of the light extracting film 20.

Table 5 shows the rate of increase of optical efficiency according to the concentration of glass beads. At this time, the beads were fixed with glass beads, and the size of the glass beads was fixed to 2000 nm.

Conventional 30% 50% 70% Luminous efficiency (lm / W) 4.92 6.5 6.67 6.33 Increase in optical efficiency (%) 100 132.1 135.6 128.7

Referring to Table 5, when the concentration of the glass beads is 30%, the light efficiency is 6.5 lm / W, which is 32.1% higher than that of the conventional art. When the concentration of the glass beads is 50%, the optical efficiency is 6.67 lm / W, which is 35.6% higher than the conventional optical efficiency. When the concentration of the glass beads is 70%, the light efficiency is 6.33 lm / W, which is 28.7% higher than that of the prior art.

When the concentration of the glass beads is less than 30%, the rise of the optical efficiency due to the glass beads decreases. When the concentration of the glass beads exceeds 70%, the transmittance decreases and the increase in the optical efficiency decreases.

3 is a view showing an organic light emitting device according to a second embodiment.

The organic light emitting device according to the second embodiment is the same as the first embodiment except that a quantum dot film is added as compared with the first embodiment. Therefore, in describing the second embodiment, the same reference numerals are assigned to the same components as those of the first embodiment, and a detailed description thereof is omitted.

Referring to FIG. 3, the organic light emitting device 1 according to the second embodiment may include the organic light emitting device 10, the light extracting film 20, and the quantum dot film 40.

The light extracting film 20 and the quantum dot film 40 may be sequentially stacked on the organic light emitting diode 10.

The organic light emitting device 10 and the quantum dot film 40 may be adhered to the light extracting film 20 by an adhesive layer 30.

The adhesive layer 30 may be formed of PDMS or OCA material. The adhesive layer 30 may include a first adhesive layer 31 and a second adhesive layer 33.

The first adhesive layer 31 may be interposed between the organic light emitting device 10 and the light extracting film 20 to attach the light extracting film 20 to the organic light emitting device 10. The first adhesive layer 31 may be applied to the entire surface of the light extracting film 20.

The second adhesive layer 33 may be interposed between the light extracting film 20 and the quantum dot film 40 to attach the quantum dot film 40 to the light extracting film 20. The second adhesive layer 33 may be applied to the entire surface of the light extracting film 20.

The first adhesive layer 31 and the second adhesive layer 33 may be formed of the same material.

The quantum dot film 40 may include a quantum dot. The quantum dots may be uniformly mixed in the quantum dot film 40.

The quantum dot is a nano-sized semiconductor material and exhibits a quantum confinement effect. Such a quantum dot absorbs light from an excitation source, and upon reaching an energy-excited state, emits energy corresponding to an energy band gap of the corresponding quantum dot. Accordingly, when the size or the material composition of the quantum dots is controlled, the corresponding energy band gap can be controlled, and various light can be emitted, thereby being used as an emitter of an electronic device.

The nano-sized semiconductor material may be selected from Group II-VI compounds, Group III-V compounds, Group IV-VI compounds, Group IV compounds, or mixtures thereof.

CdSeS, CdSeS, CdSeS, ZnSeS, ZnSeTe, ZnSTe, HgSeS, HgSeTe, HgSTe, CdZnS, HgSe, HgTe, ZnTe, ZnSe, ZnTe, ZnO, A trivalent compound such as CdZnSe, CdZnTe, CdHgS, CdHgSe, CdHgTe, HgZnS, HgZnSe, or a ternary compound such as HggZnTe, CdZnSeS, CdZnSeTe, CdZnSTe, CdHgSeS, CdHgSeTe, CdHgSTe, HgZnSeS, HgZnSeTe, HgZnSTe have.

The group III-V compound may be one of GaN, GaNAs, GaNSb, GaPAs, GaPSb, AlNP, AlNAs, GaN, GaN, GaN, GaN, GaN, AlN, AlN, AlN, InAlPb, InAlPb, InAlPb, InAlPb, InAlPb, InAlPb, InAlPb, InAlPb, InAlPb, InAlPb, InAlPb, InAlPb, InAlPb, InAlPb, , And the like.

The IV-VI compound may be at least one selected from the group consisting of ternary compounds such as SnSeS, SnSeS, SnSeTe, SnSTe, PbSeS, PbSeTe, PbSTe, SnPbS, SnPbSe and SnPbTe, SnPbSSe, SnPbSeTe , SnPbSTe, and the like.

The Group IV compound may be selected from the group consisting of single element compounds such as Si and Ge, or these element compounds such as SiC and SiGe.

In the case of the elemental compound, the trivalent compound, or the silane compound, the crystal structure thereof may be partially contained and exist in the same particle or in the form of an alloy.

4 is a view showing an organic light emitting device according to the third embodiment.

The organic light emitting device according to the third embodiment is the same as the first embodiment except that a quantum dot film is added in comparison with the first embodiment. Therefore, in describing the third embodiment, the same reference numerals are assigned to the components common to those of the first embodiment, and a detailed description thereof is omitted.

Referring to FIG. 4, the organic light emitting device 1 according to the third embodiment may include the organic light emitting device 10, the light extracting film 20, and the quantum dot film 40.

The quantum dot film 40 and the light extracting film 20 may be sequentially stacked on the organic light emitting device 10.

The organic light emitting device 10 and the light extracting film 20 may be bonded to the quantum dot film 40 by an adhesive layer 30.

The adhesive layer 30 may be formed of PDMS or OCA material. The adhesive layer 30 may include a first adhesive layer 31 and a second adhesive layer 33.

The first adhesive layer 31 may be interposed between the organic light emitting device 10 and the quantum dot film 40 to attach the quantum dot film 40 to the organic light emitting diode 10. The first adhesive layer 31 may be applied to the entire surface of the quantum dot film 20.

The second adhesive layer 33 may be interposed between the light extracting film 20 and the quantum dot film 40 to attach the quantum dot film 40 to the light extracting film 20. The second adhesive layer 33 may be applied to the entire surface of the quantum dot film 40.

The first adhesive layer 31 and the second adhesive layer 33 may be formed of the same material.

The quantum dot film 40 may include a quantum dot.

5 is a diagram showing the light efficiency of the organic light emitting device of the first to third embodiments, and Table 6 is a table showing the light efficiency of the organic light emitting device of the first to third embodiments.

Conventional First Embodiment Second Embodiment Third Embodiment Luminous efficiency (lm / W) 4.2 5.92 5.67 5.58 Increase in optical efficiency (%) 100 141 135 133

5 and 6, in the sequentially stacked structure of the light extracting film 20 and the quantum dot film 40 of the second embodiment, the organic light emitting device has a light efficiency of 5.67 lm / W, I have. The organic light emitting device in the sequential lamination structure of the quantum dot film 40 and the light extracting film 20 of the third embodiment has a light efficiency of 5.58 lm / W and thus has a light efficiency increase rate of 33% as compared with the conventional one.

5, the second embodiment and the third embodiment have a wide range of light distribution as compared to the conventional and first embodiments. Particularly, in the second embodiment and the third embodiment, the intensity of light is increased at a long wavelength, and relatively uniform light can be emitted as compared with the conventional and first embodiments.

The second embodiment and the third embodiment have a wide range of light distribution, thereby increasing the CRI (Color Rendering Index). The CRI represents the degree of change of the color of the object when the natural light (similar to black body radiation) having the same color temperature and the artificially produced illumination are irradiated to the same object, and the natural light, that is, the black body radiation, Indicating how close the illumination is to this. As the CRI approaches 100, the light emitting device implements white light close to natural light.

The CRI can be raised by the second and third embodiments, so that light similar to natural light can be emitted in a simple manner.

6 is a view showing an organic light emitting device according to a fourth embodiment.

The organic light emitting device according to the fourth embodiment is the same as the second embodiment except that a light extracting film is further added. Therefore, in describing the fourth embodiment, the same reference numerals are assigned to the components common to the second embodiment, and the detailed description is omitted.

6, the organic light emitting device 1 according to the fourth embodiment includes an organic light emitting device 10, a first light extracting film 21, a second light extracting film 23, and a quantum dot film 40 .

The first light extracting film 21, the quantum dot film 40 and the second light extracting film 23 may be sequentially stacked on the organic light emitting device 10.

The organic light emitting device 10, the first light extracting film 21, the quantum dot film 40 and the second light extracting film 23 may be adhered to each other by the adhesive layer 30.

The adhesive layer 30 may be formed of PDMS or OCA material. The adhesive layer 30 may include a first adhesive layer 31, a second adhesive layer 33, and a third adhesive layer 35.

The first adhesive layer 31 may be interposed between the organic light emitting device 10 and the first light extracting film 21 to attach the first light extracting film 21 to the organic light emitting device 10. [ have. The first adhesive layer 31 may be applied to the entire surface of the first light extracting film 21.

The second adhesive layer 33 may be interposed between the first light extracting film 21 and the quantum dot film 40 to attach the quantum dot film 40 to the first light extracting film 21. The second adhesive layer 33 may be applied to the entire surface of the quantum dot film 40.

The quantum dot film 40 may include a quantum dot.

The third adhesive layer 35 may be interposed between the quantum dot film 40 and the second light extracting film 23 to attach the second light extracting film 23 to the quantum dot film 40. The third adhesive layer 35 may be applied to the entire surface of the second light extracting film 23.

The light efficiency of the organic light emitting device 1 is improved by the first light extracting film 21, the second light extracting film 23 and the quantum dot film 40 and the CRI of emitted light is increased.

The first light extracting film 21 and the second light extracting film 23 may have the same optical characteristics. The first light extracting film 21 and the second light extracting film 23 may be attached to both sides of the quantum dot film 40 to protect the quantum dot film 40.

7 is a view showing an organic light emitting device according to a fifth embodiment.

The organic light emitting device according to the fifth embodiment is the same as the first embodiment except that the mixed film except for the light extracting film is applied as compared with the first embodiment. Therefore, in describing the fifth embodiment, the same reference numerals are assigned to the components common to those of the first embodiment, and a detailed description thereof will be omitted.

Referring to FIG. 7, the organic light emitting device 1 according to the fifth embodiment may include the organic light emitting device 10 and the mixed film 50.

The mixed film 50 may be adhered to the organic light emitting device 10 through the adhesive layer 30. The adhesive layer 30 is sandwiched between the organic light emitting device 10 and the immersion film 50 to fix the immersion film 50 to the organic light emitting device 10.

The inclusion film 50 may include beads 51 and quantum dots 53. The beads 51 and the quantum dots 53 may be uniformly mixed in the mixed film 50. The beads 51 may be glass beads or acrylic beads.

The light efficiency of the light generated from the organic light emitting element 10 is improved by the beads 51 and the quantum dots 53 included in the mixed film 50 and the light of a wide wavelength range can be outputted homogeneously . The above effect can be confirmed by FIG. 8 and Table 7.

Conventional Comparative Example 1 Comparative Example 2 Fifth Embodiment Luminous efficiency (lm / W) 2.32 3.11 3.24 3.57 Increase in optical efficiency (%) 100 134 139 153

8 and 7, the first comparative example shows an organic light emitting device including a light extraction film 20 in which beads are incorporated, and the second comparative example shows an organic light emitting device including a film incorporating a quantum dot .

The first comparative example has a luminous efficacy of 3.11 lm / W and has a luminous efficiency increase rate of 34% compared with an organic light emitting device which does not include a conventional film. The second comparative example has a luminous efficiency of 3.24 lm / As shown in FIG. On the other hand, the organic light emitting device including the mixed film 50 according to the fifth embodiment has a light efficiency of 3.57 lm / W and a luminous efficiency increase rate of 53% as compared with the prior art.

The intensity of the light according to the wavelength is smaller in the short wavelength range having the blue light than the first and second comparative examples. However, in the long wavelength range having red light, the intensity of light is larger than that of the first comparative example and the second comparative example. The intruding film 50 can reduce the intensity of light having a relatively large intensity in a short wavelength range and intensify light intensity in a long wavelength range, thereby obtaining uniformly light as a whole. That is, there is an effect that the CRI is increased by the inclusion film (50).

With respect to the overall optical efficiency, the optical efficiency of the fifth embodiment is much higher than that of the first and second comparative examples because the intensity of the light in the long wavelength range increases sharply instead of the light of the short wavelength range.

The impregnated film 50 may have a thickness within a certain range. The impregnated film 50 may have a thickness of 150 [mu] m to 1000 [mu] m. Preferably, the impregnated film 50 may have a thickness of 500 um. 9 shows the distribution of the output light according to the wavelength of the incident film.

Referring to FIG. 9, when the mixed film 50 has a range of 150 to 1000 um, the CRI rises. Particularly, when the mixed film 50 has a thickness of 500 um, homogeneous light is radiated to realize light having a high CRI.

While the present invention has been described with reference to exemplary embodiments, it is to be understood that the invention is not limited to the disclosed exemplary embodiments, but, on the contrary, It will be apparent to those skilled in the art that changes or modifications may fall within the scope of the appended claims.

1: organic light emitting device
10: Organic light emitting device
11: first electrode
13: Organic light emitting layer
15: second electrode
17: substrate
20: Light extraction film
30: Adhesive layer
40: Quantum dot film
50: Entrapment film
51: Glass beads
53: Quantum dot

Claims (15)

An organic light emitting element for outputting light;
A light extracting film formed on the organic light emitting element; And
And an adhesive layer interposed between the light extracting film and the organic light emitting device to bond the organic light emitting device and the light extracting film,
Wherein the light extracting film comprises acrylic beads,
Wherein the light extracting film comprises a first light extracting film and a second light extracting film,
Further comprising a quantum dot film interposed between the first light extracting film and the second light extracting film,
Wherein the adhesive layer is a polymer material comprising an adhesive material,
The acrylic beads have a size of 4 um to 20 um,
The adhesive material is PDMS,
Wherein the refractive index of the acrylic beads is 1.49 and the refractive index of the PDMS is 1.45. The method according to claim 1,
Wherein the light extracting film is attached to the adhesive layer after the adhesive layer is attached to the organic light emitting element. delete The method according to claim 1,
Wherein the organic light emitting device comprises a substrate,
Wherein a difference in refractive index between the substrate and the adhesive layer is 5% or less. delete delete delete The method according to claim 1,
Wherein the thickness of the light extracting film is 50 mu m to 300 mu m. The method according to claim 1,
Wherein the beads have a concentration of 30% to 70%. delete The method according to claim 1,
And a quantum dot film formed between the light extracting film and the organic light emitting device. The method according to claim 1,
Wherein the light extracting film further comprises a plurality of quantum dots,
Wherein at least one of the first light extracting film and the second light extracting film contains the acrylic beads and the quantum dots. 13. The method of claim 12,
Wherein the light extracting film in which the acrylic beads and the quantum dots are mixed in the first light extracting film and the second light extracting film has a thickness of 150 um to 1000 um.

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