KR101564067B1 - Light emitting diode display for display back light unit using matrials for improving color reproduction range - Google Patents

Abstract

According to the present invention, there is provided a white light emitting diode device for realizing an advantage of a color gamut index of a white device using R, G, and B primary LEDs on a PC-LED in a BLU white LED device for LCD. The white light emitting diode device includes white light through a blue LED chip and a phosphor, and includes a phosphor and an absorbing material capable of absorbing a wavelength of a specific region and separating the spectra of green and red light regions, It is possible to improve the color recall index, which is a disadvantage of the PC-LED.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a light-emitting diode device for a display backlight unit (BLU)

The present invention relates to an auxiliary agent or an improvement agent capable of improving the color reproducibility index in manufacturing a light emitting diode element for a display backlight unit (BLU), and a light emitting diode including the same.

Along with the development of multimedia devices such as TVs, notebooks, mobile phones, etc., the demand for flat panel displays has increased, and the spread of LCDs has been activated.

A white light emitting diode (hereinafter, referred to as LED) device which has a high luminance, a long life and does not emit heat has attracted attention as a backlight source of an LCD display instead of a conventional CCFL. A white LED is implemented by arranging a blue (B) LED chip, a green (G) LED chip and a red (R) LED chip as a white light source for a conventional back light unit (BLU). As described above, the white LED device using the three primary color chips of R, G and B is relatively excellent in the color rendering index and has an advantage that the overall output light can be controlled by adjusting the light amount of blue, green and red LEDs. However, since the LED elements have different electrical characteristics to drive and control the LEDs of the individual colors, circuit driving becomes complicated, thereby increasing manufacturing costs. In addition, in the case of the LED device, there are disadvantages in that it is difficult to control the color temperature caused by using the R, G, and B primary color LEDs and a deviation occurs depending on the temperature.

To overcome these disadvantages, development of a phosphor-converted LED (PC-LED) for emitting a phosphor by using a blue LED as an excitation source has been proposed. For example, white light can be realized by mixing red phosphor with InGaN-based blue LED using Garnet, Silicate, Nitride series down-conversion light emitting yellow phosphor and silicone and epoxy resin. This method has the advantages of simple circuit configuration and low cost, but the color reproduction ratio index is not good on NTSC due to the relatively low light intensity and color reproduction range in the long wavelength. In case of LED light source including blue LED chip and yellow phosphor, the color recall index of YAG-based phosphor is about 73% compared to NTSC even when R, G and B color filters are applied as back light unit (BLU) , And about 68% even in the case of using a silicate yellow phosphor. In order to satisfy various color characteristics when applying BLU for LCD, a method of mixing green and red phosphors on a blue LED chip is required, and in order to improve the color recall index, a method of increasing the color purity of each phosphor A phosphor having a reduced half width is proposed. However, since there are a limited number of phosphors satisfying these requirements, an additional method for displaying an improved color reproduction index index is required to manufacture a high-quality and low-cost LCD display.

In addition, Korean Registration No. 0906566 provides an LCD backlight unit (BLU) using an absorbing film to enhance the purity of green and red wavelengths by absorbing light in a wavelength range of 578 to 598 nm, thereby improving the color recall index have. The above method employs a commercially available absorbing film. The absorbing film is adhered to the bottom surface of the prism sheet located above the upper surface of the light guide plate in the LCD backlight unit, or attached to the bottom surface of the diffusion plate. However, the above-described method is merely a methodological aspect using a commercialized film, and it is troublesome to attach an additional absorbing film when applied to a BLU. In addition, the above method has a limitation of the chromaticity arithmetic index by absorbing only the spectrum in the range of 578 to 598 nm, and there is a problem that the optical brightness drop rate remarkably increases in the spectrum when the phosphor is excited by the excitation source of blue LED.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a color reproducibility index which is one of the problems of a PC-LED (Phosphor converted LED) The present invention provides a white LED device capable of improving the purity and emission intensity of green and red regions by separating wavelengths of green and red regions by removing a spectrum of a specific wavelength by using an absorbing modifier .

The present invention relates to a device for realizing white light by a blue LED chip including a light source and at least one fluorescent substance capable of converting wavelength of blue light from the blue LED chip to a red to green region, And a color reproducibility improving agent that absorbs the region of 490 to 520 nm and the region of 550 to 590 nm in a white light emitting diode device.

The color gamut modifier _{Nd 2 O 3, NdAlO 3,} Nd 2 TiO 5, Nd 2 Ti 2 O 7, NdTiO 3, Sr 3 Nd 4 O 9, Nd 2 Si 2 O 7, CaNd 4 Si 3 O 13, NdB ₃ O ₆ , and Nd _{0 .1} La ₂ CaB ₁₀ O ₁₉ ; Zn-popyrinth, 1,3-bisdicyanovinylindane, C ₂₁ H ₂₂ N ₃ OClO ₄ , C ₃₇ H ₃₉ ClN ₂ O ₉ , C ₃₂ H ₃₁ N ₂ O ₃ ClO ₄ , C ₃₁ H ₃ O ₂ At least one organic compound selected from the group consisting of O ₇ S ₂ Na, C ₃₁ H ₃ O _{2 2} O ₇ S ₂ , and C ₂₃ H ₂₃ N ₂ O ₂₁ ; Or mixtures thereof.

The color reproducibility improving agent may be (a) completely or partially dispersed in a molding member or a casing for encapsulating and sealing the blue LED chip and the phosphor, or (b) may be contained in the upper part of the phosphor contained in the blue LED chip have.

In the above (a), a mixture of a color reproducibility improving agent, a phosphor and a molding member; Or a mixture of a color reproducibility improving agent, a fluorescent substance and an exterior material is applied to the inside or the top of the blue LED chip, the color reproduction ratio improving agent may be wholly or partly dispersed in the molding member or the exterior material.

In the above (b), a color reproducibility improving agent may be included in a method of applying a mixture of a color reproducibility improving agent and a molding member on a phosphor included in or on a blue LED chip.

In addition, the phosphor may include at least one selected from the group consisting of a yellow phosphor, a green phosphor, and a red phosphor.

According to the present invention, the spectral separation effect of the green and red wavelength regions is improved by using the color reproducibility improving agent, which is an absorption improving material, in the specific light region, more specifically, in the light absorption of the region of 490 to 520 nm and 560 to 580 nm It is possible to provide a light emitting diode having improved color reproduction rate index.

FIG. 1 shows a comparison of a white light source implementation spectrum and a simulation result of an increase in color recall ratio index on NTSC for the problem to be solved by the present invention.
FIG. 2 illustrates a structure of a surface-mounted white light emitting diode according to an embodiment of the present invention. Referring to FIG.
FIG. 3 illustrates another structure of a white light emitting diode in a surface mount type according to another embodiment of the present invention.
FIG. 4 is a view illustrating a structure of application of an absorption enhancing material to a white light emitting diode in a surface mount type according to another embodiment of the present invention.
FIG. 5A shows a spectrum according to Example 1. FIG.
5B is a graph of NTSC according to the first embodiment.
FIG. 6A shows a spectrum according to Example 2. FIG.
6B shows an NTSC graph according to the second embodiment.
7 shows an NTSC graph according to the third embodiment.
8 shows an NTSC graph according to the fourth embodiment.
9 shows an NTSC graph according to the fifth embodiment.
10 shows the results of reduction of the half-width of the phosphor when NdAlO _{3 was} added in Experimental Example 1 and Example 1, respectively.

The terminology used herein is for the purpose of describing exemplary embodiments only and is not intended to be limiting of the invention. The singular expressions include plural expressions unless the context clearly dictates otherwise. In this specification, the terms "comprises, " or" having ", and the like, are intended to specify the presence of stated features, integers, Components, or combinations thereof, as a matter of convenience, without departing from the spirit and scope of the invention.

In addition, the present invention can be variously modified and can take various forms, so that specific embodiments are exemplified and will be described in detail below. It should be understood, however, that the invention is not intended to be limited to the particular forms disclosed, but on the contrary, is intended to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the invention.

The light emitting diode described in the specification of the present invention includes a light emitting diode element or a light emitting element.

Hereinafter, a white LED according to a specific embodiment of the present invention will be described in detail.

According to an embodiment of the present invention, there is provided a device for realizing white light by a blue LED chip including a light source and at least one phosphor capable of converting wavelength of blue light from the blue LED chip into a red to green region, And a color reproducibility improving agent that absorbs the region of 490 to 520 nm and 550 to 590 nm in the interior or the upper portion of the chip.

The white light emitting diode device of the present invention includes a blue LED chip including a light source; At least one phosphor capable of converting wavelengths of blue light from the blue LED chip from green to red; And a color reproducibility improving agent that absorbs 490 to 520 nm and 550 to 590 nm regions.

The color reproducibility improving agent mentioned in the present invention means an absorption improving material containing a specific wavelength for increasing the color reproducibility index, and the range of manifesting the characteristic may be different depending on the absorbing material. In addition, the color reproducibility improving agent includes an adjuvant or an improvement agent capable of improving the color reproducibility index in manufacturing a light emitting diode device for a display backlight unit (BLU). Preferably, the absorption peak area of the color reproducibility improving agent is between 490 and 520 nm and between 550 and 590 nm.

Accordingly, the present invention is characterized by providing a light-emitting diode having an improved color reproduction index using a material that absorbs a specific region, more specifically, an improvement material that absorbs the 490 to 520 nm and 550 to 580 nm regions. The absorption of the spectrum of the specific region by the absorbing material can give an effect of spectral separation between the green region and the red region, and thus the role of the absorption filter used can be expected.

The color reproducibility improving agent that provides such a characteristic may be an inorganic compound or an organic compound, and the inorganic compound may be any Nd-containing inorganic compound centered on Nd. The color reproducibility improving agent may be used as a part or whole of organic / inorganic compounds. More preferably an inorganic compound which is centered around the Nd are _{Nd 2 O 3, NdAlO 3,} Nd 2 TiO 5, Nd 2 Ti 2 O 7, NdTiO 3, Sr 3 Nd 4 O 9, Nd 2 Si 2 O 7, CaNd ₄ Si ₃ O ₁₃ , NdB ₃ O ₆ , and Nd _{0 .1} La ₂ CaB ₁₀ O ₁₉ . The organic compound may be Zn-porphyrins (C ₂₀ H ₁₄ N ₄ Zn), 1,3-bisdicyanovinylindane, C ₂₁ H ₂₂ N ₃ OClO ₄ , C ₃₇ H ₃₉ ClN ₂ O ₉ , C ₃₂ H ₃₁ N ₂ O ₃ ClO ₄ , C ₃₁ H ₃ O _{2 2} O ₇ S ₂ Na, C ₃₁ H ₃ O _{2 2} O ₇ S ₂ , and C ₂₃ H ₂₃ N ₂ O ₂₁ < / RTI >

In addition, the above-mentioned conventional Korean Registration No. 0906566 absorbs the spectrum of the 578 to 598 nm region, but in the case of the present invention, by absorbing the spectrum of 550 to 590 nm and 490 to 520 nm region including the color reproducibility improving agent, It is possible to provide a higher level of color recall index. In addition, in the case of applying the conventional method to the BLU, a separate additional process for attaching an absorbing film is required. However, in the case of the present invention, since the blue LED chip includes an enhancer for absorbing a region of 490 to 520 nm and 550 to 590 nm, It is applicable.

In the conventional method, the optical brightness drop rate is remarkably large in the spectrum when the phosphor is excited by the excitation source of blue LED, but in the present invention, the optical brightness of the phosphor is equal to that of the absorption portion. That is, the above-described conventional method still has a problem of lowering the optical brightness which is important on the phosphor-converted LED, and the present invention has secured such a problem. In the case where the improvement of the color recall index on NTSC occurs simultaneously with the decrease in optical brightness, it is impossible to apply the technique as a commercialized technology. Therefore, it is essential to overcome such a problem.

Meanwhile, the light emitting diode of the present invention includes a blue LED chip having a main wavelength of 450 to 455 nm and at least one or more phosphors excited by the blue LED chip and used for emitting light. It is preferable that the phosphor includes at least one selected from the group consisting of a yellow phosphor, a green phosphor and a red phosphor. The range of the luminous color according to the inclusion of the phosphor is yellow light emitted from the green region to the red region, and a white LED element including an absorbing material is provided inside or above the blue LED chip.

At this time, as described above, the peak of the wavelength absorbed by the color reproducibility improving agent which is the absorption improving material is in the range of 490 to 520 nm and 550 to 580 nm. According to the present invention, when the peak of the wavelength absorbed by the color reproduction rate improver exceeds the above range, the green region and the red region light are insufficiently lighted, so that the overall light efficiency and the color imbalance may occur.

FIG. 1 shows a comparison of a white light source implementation spectrum and a simulation result of an increase in color recall ratio index on NTSC for the problem to be solved by the present invention.

As shown in FIG. 1, the spectrum of the specific region proposed in the present invention is removed through simulation. As a result, the color recall index on the PC-LED greatly increases from 73% to 89%. That is, according to the present invention, it is possible to provide an improvement in the color recall index on the PC-LED spectrum.

The absorbing material may be wholly or partly dispersed in the molding member or the covering material or included in the upper portion of the fluorescent material when the absorbing material is contained in the interior or upper part of the blue LED chip. In order to achieve the object of the present invention, a method of mixing a phosphor, an encapsulant and an absorbing material on a blue LED chip, a method of mixing a phosphor and a sealing agent, applying a blue LED chip, And the like. The encapsulant includes a blue LED chip well known in the art and a molding member or sheath for encapsulating and sealing the phosphor. The molding member may be made of a colorless or colored light transmitting resin. More specific details will be given in the examples.

More specifically, the color reproducibility improving agent may be (a) dispersed wholly or partly in a molding member or a casing for encapsulating and sealing the blue LED chip and the phosphor, or (b) Can be included in the upper part.

In (a), a mixture of the color reproducibility improving agent, the phosphor and the molding member; Or a mixture of a color reproducibility improving agent, a fluorescent substance and an exterior material is applied to the inside or the top of the blue LED chip, the color reproduction ratio improving agent may be wholly or partly dispersed in the molding member or the exterior material.

The phosphor in (b) may be prepared by applying a mixture of a phosphor and a molding member or a mixture of a color reproducibility improving agent, a phosphor and a molding member to the inside or the top of the blue LED chip before applying the mixture of the color reproducibility improving agent and the molding member ≪ / RTI > Further, according to the above-described method, the molding material is partially or wholly dispersed in the phosphor or the phosphor and the color reproducibility improving agent or the phosphor.

The content of the color reproducibility improving agent may be 5 to 90% by weight, more preferably 20 to 50% by weight, based on the total weight of the phosphor and the color reproducibility improving agent (absorption improving material) or the total weight of the phosphor. Generally, when the content of the color reproducibility improving agent is less than 50% by weight, the effect of increasing the color recall index on the NTSC is hardly manifested. If the content is more than 90% by weight, the optical brightness may greatly decrease. However, the content of the color reproducibility improving agent in the present invention may vary depending on the kind thereof, and therefore, the weight of the color improving agent is not limited to the above-mentioned weight, and the absorption improving material may exceed the weight of the phosphor depending on the type of color reproducibility improving agent.

The phosphor may include at least one selected from the group consisting of a yellow phosphor, a green phosphor, and a red phosphor. The types of the phosphors are not particularly limited, and general materials used for light emitting diodes can be used, and the kind thereof is not particularly limited. In addition, the phosphor may be included in the remainder of the total weight of the phosphor and the color reproducibility improving agent, and the ratio of each phosphor may be appropriately controlled when one or more of the phosphors is used in combination. For example, when the yellow phosphor, the green phosphor, and the red phosphor are mixed, the phosphor to be used may be mixed at a weight ratio of 45:45:10.

In addition, the white light emitting diode of the present invention may include, in addition to the above components, a reflective cup well known in the art, a lead frame of a positive electrode and a negative electrode, a bonding wire, a casing for molding the entire periphery of the LED chip, And the structure thereof is not limited. Also, the content range of the molding member is not limited, and can be used as is well known in the art based on the total weight of the phosphor and the color reproducibility improving agent (absorbing material) or the total weight of the phosphor.

The light emitting diode device of the present invention having such a configuration exhibits high color rendering properties and can be efficiently used as a light source for producing a high quality LCD display.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. The form of the embodiment described below is provided as a reference example for explaining the details of the present invention. Therefore, the embodiments of the present invention can be modified into various other forms, and the scope of the present invention is not limited to the embodiments described below.

2 is a view illustrating a structure of a surface-mounted white light emitting diode according to an embodiment of the present invention. FIG. 2 shows an example in which the color reproducibility improving agent is dispersed in the casing together with the phosphor in whole or in part.

2, the white light emitting diode includes an InGaN light emitting diode chip 110 and a reflector (not shown) for reflecting the light emitted from the light emitting diode chip 110 above the white light emitting diode A bonding wire 140 for electrically connecting the light emitting diode chip 110 to the lead frame 130 of the positive and negative electrodes and a bonding wire 140 for electrically connecting the entire periphery of the light emitting diode chip 110, And a color reproduction rate improver for absorbing a specific wavelength and a phosphor 160 that is totally or partially dispersed in the exterior material 150. The color reproduction rate improver 150 may be a colorless or colored light transmission resin. Although the color reproducibility improving agent is not shown in the drawing, it is dispersed in the casing together with the phosphor in whole or in part.

3 is a view illustrating another structure of a surface-mounted white light emitting diode according to another embodiment of the present invention. In the case of Fig. 3, the color reproducibility improving agent is dispersed in the molding member together with the phosphor in whole or in part.

3, the light emitting device includes a light emitting diode chip 110, a substrate 121 for supporting the light emitting diode chip 110 and reflecting the light emitted from the light emitting diode chip 110 in the upward direction, Two electrically isolated electrode layers 131 for providing power to the LED chip 110 and a wire 140 for electrically connecting the LED chip 110 and the electrode layer 131 to each other, A phosphor 160 which is wholly or partly dispersed in a molding member 151 made of a colorless or colored light transmitting resin that molds the diode chip 110 and a color gamut improvement agent are included. In the light emitting device shown in FIG. 3, one wire 140 electrically connects the light emitting diode chip 110 and one electrode layer 131. The light emitting diode chip 110 is directly electrically connected to the other electrode layer 131.

Preferably, in the case of the light emitting device using the light emitting diode, the phosphor is excited by the compound semiconductor to use a phosphor having a center wavelength of 490 to 700 nm, and includes a phosphor and a color reproducibility improving agent for absorbing a specific region, Accordingly, a light emitting diode using the same can be provided. Referring to FIG. 3, the phosphor 160 and the color reproducibility improver may be partially or wholly dispersed in the molding member 151, and the phosphor converts a part of blue light emitted from the LED chip into light having a yellow region wavelength . In addition, although the color reproducibility improving agent is not shown in the drawing, it is dispersed in the casing together with the phosphor in whole or in part. That is, when a yellow phosphor is used for a blue LED chip, the converted light has a spectrum in which light is mixed in a range from a green region to a red region. This is because the purity of the spectrum corresponding to green and red is not high and the color recall ratio index is low only by virtue of the above application. Accordingly, the color reproducibility improver absorbs the wavelengths of the specific wavelength of the converted yellow light, more specifically, the wavelengths of 490 to 520 nm and 550 to 580 nm, and separates the green and red spectrum Purity and light intensity can be increased and the role of the color filter which is used in the past can be expected.

FIG. 4 is a view illustrating a structure in which a color reproduction rate improver is additionally applied to a white light emitting diode of a surface mounting type according to another embodiment of the present invention to form a layer. In the case of FIG. 4, the color reproducibility improver is dispersed in the molding member together with the phosphor in whole or in part, and then the color reproducibility improving agent is further applied onto the phosphor.

The structure and the shape of the white light emitting diode shown in FIG. 4 are the same as those of the white light emitting diode shown in FIG. 3, and a molding member 151 made of a colorless or colored light transmitting resin for molding the light emitting diode chip 110 The phosphor 160 is completely or partially dispersed. In addition, a color reproducibility improver 161, which absorbs a specific region, is further included in the mold material and is applied and mounted on the phosphor 160, thereby providing a light emitting diode using the same.

4, the phosphor 160 and the color reproducibility improving agent may be partially or wholly dispersed in the molding member 151, and may have a shape in which the color reproducibility improving agent is additionally coated on the phosphor have. Additional structural features are shown in Fig. When the color reproducibility improving agent is further applied to the upper portion of the phosphor, there is no limitation on the thickness, but it may preferably be 50% to 30% of the thickness of the inside of the LED chip.

Hereinafter, the present invention will be described in more detail with reference to the following examples. However, the scope of the present invention is not limited to the following examples.

≪ Example 1 >

Color recall  The spectrum due to the dispersion due to the addition of the modifier and NTSC Color recall

Green and yellow phosphors were mixed with red phosphors and NdAlO ₃ was added as a color reproducibility improving agent to improve the absorption spectrum to confirm the change of the optical spectrum and NTSC. At this time, NdAlO ₃ was used as a color reproducibility improving agent. The use ratio of NdAlO _{3 was} 30 wt%, the green phosphor was 31.5 wt%, the yellow phosphor was 31.5 wt%, and the red phosphor was 7 wt%. The phosphor was mixed with 1200 parts by weight of a molding material, And applied on the blue LED chip. FIG. 5A shows a spectrum according to Example 1. FIG. 5B shows a graph of NTSC according to the first embodiment. 5A and 5B, the NTSC increased from 72.63% to 77.99% as NdAlO ₃ was added. Addition of NdAlO ₃ also caused absorption in the spectrum of the yellow region, resulting in the separation of the green and red region spectra.

≪ Example 2 >

Color recall  Remedy Coating layer  The spectra of formation and NTSC Color recall

50% of the inner thickness of the blue LED chip was coated by blending 45% by weight of the green phosphor, 45% by weight of the yellow phosphor, and 10% by weight of the red phosphor with 1200 parts by weight of the molding material. Then, 30 parts by weight of NdAlO ₃ , which is a color reproducibility improving agent, and 1200 parts by weight of a molding material are mixed with 100 parts by weight of the total amount of the phosphors, and 50% of the thickness of the blue LED chip is further coated on the phosphor to form an absorbent material layer After that, the changes of optical spectrum and NTSC were confirmed.

FIG. 6A shows a spectrum according to Example 2. FIG. 6B shows an NTSC graph according to the second embodiment. 6A and 6B, as the NdAlO ₃ was further applied, the blue region was reduced to be close to the standard NTSC, and the green and red regions were increased to increase the NTSC from 72.63% to 75.36%. Addition of NdAlO ₃ also caused absorption in the spectrum of the yellow region, resulting in the separation of the green and red region spectra.

≪ Example 3 >

Color recall  Depending on the amount of modifier added NTSC Color recall  Difference

The change of NTSC according to the ratio of NdAlO ₃ , which is a color recall ratio improving agent, is shown. NdAlO ₃ is mixed and applied to the mold member together with the phosphor as in Example 1, and the ratio is as shown in Table 1 below. At this time, the total ratio of NdAlO ₃ and the phosphor was 100 wt%, and the ratio of NdAlO ₃ was changed to 0, 30, 50, and 70 wt%. 7 shows an NTSC graph according to the third embodiment.

According to the results shown in Table 1 and FIG. 7, the NTSC value increased from 72.63% to 77.99% as the ratio of NdAlO _{3 to} the phosphor varied from 0%, 30%, 50% and 70% by weight.

<Example 4>

Color recall  Depending on the application amount of the improving agent NTSC Color recall  Difference

The change of NTSC according to the application ratio of NdAlO ₃ , which is a color reproduction ratio improving agent, is shown. As in Example 2, green and yellow phosphors and red phosphors were included in the mold member, and 50% of the blue LED chip inner thickness was coated thereon. NdAlO ₃ was mixed with the mold member in the same amounts as in Table 2, and then 50 % Was further applied to form a color reproducibility improving agent layer, and then the change of the optical spectrum and NTSC was confirmed.

At this time, the content ratios of the detailed phosphors and absorbing materials are shown in Table 2 below. 8 shows an NTSC graph according to the fourth embodiment.

In the results of Table 2 and FIG. 8, the NTSC value increased from 73.47% to 76.65% as the ratio of NdAlO ₃ was changed to 30, 50 and 70% by weight.

&Lt; Example 5 >

representative Color recall  Depending on the type of improvers NTSC Color recall  Difference

The difference of the color recall index according to the kind of the color recall ratio improving agent was suggested. The color reproducibility improving agent is mixed and applied to the mold member together with the phosphors as in Example 1, and the types and ratios thereof are shown in Table 3 below. At this time, the total ratio of the color reproducibility improving agent and the phosphor was 100% by weight, and the ratio of the color reproducibility improving agent was 30% by weight. 9A and 9B show a spectrum and an NTSC graph according to the fifth embodiment.

<Experimental Example 1>

In the production of a light emitting diode, Comparative Example 1 was used in the case of containing only a conventional general phosphor. With respect to Comparative Example 1 and Example 1, the full width at half maximum of the phosphor according to the addition of NdAlO _{3 as a} color reproducibility improving agent was measured. The half-width measurement method is according to a conventional method.

FIG. 10 shows the results of reduction of the half-width of the phosphor when NdAlO _{3 was} added to Comparative Example 1 and Example 1. FIG. 10, the half width of the first embodiment of the present invention is about 39, whereas the half width of the first comparative example is as large as 54. According to these results, it was confirmed that the color purity can be increased by reducing the full width at half maximum of Example 1 of the present invention.

110: Light emitting diode chip
120: reflective cup
121: reflective substrate
130: lead frame
131: electrode layer
140: Bonding wire
150: Outer material
151: Molding member
160: Phosphor
161: Improvement of color reproduction rate

Claims (6)

A blue LED chip including a light source and at least one phosphor capable of converting wavelength of blue light from the blue LED chip to a red region,
And a color reproducibility improver for absorbing a region of 490 to 520 nm and 550 to 590 nm in or above the blue LED chip,
The color gamut modifier _{Nd 2 O 3, NdAlO 3,} Nd 2 TiO 5, Nd 2 Ti 2 O 7, NdTiO 3, Sr 3 Nd 4 O 9, Nd 2 Si 2 O 7, CaNd 4 Si 3 O 13, NdB _At least one Nd-containing inorganic compound selected from the group consisting of Nd _0.1 O ₃ O ₆ , and Nd _0.1 La ₂ CaB ₁₀ O ₁₉ ; Zn-popyrinth, 1,3-bisdicyanovinylindane, C ₂₁ H ₂₂ N ₃ OClO ₄ , C ₃₇ H ₃₉ ClN ₂ O ₉ , C ₃₂ H ₃₁ N ₂ O ₃ ClO ₄ , C ₃₁ H ₃ O ₂ At least one organic compound selected from the group consisting of O ₇ S ₂ Na, C ₃₁ H ₃ O _{2 2} O ₇ S ₂ , and C ₂₃ H ₂₃ N ₂ O ₂₁ ; Or a mixture thereof,
The color reproducibility improving agent may be (a) completely or partially dispersed in a molding member or a casing for encapsulating and sealing the blue LED chip and the phosphor, or (b) included in the upper part of the phosphor included in the interior or upper part of the blue LED chip White light emitting diode device.
delete delete The method according to claim 1, wherein (a) is a mixture of a color reproducibility improving agent, a phosphor and a molding member; Wherein the color reproduction rate improver is wholly or partly dispersed in the molding member or the exterior material by a method of applying the mixture of the color reproducibility improving agent, the phosphor and the exterior material to the inside or the top of the blue LED chip.
The white light emitting diode device according to claim 1, wherein the color reproducibility improving agent is included in the method (b) by applying a mixture of the color reproducibility improving agent and the molding member onto the phosphor contained in the interior or the upper portion of the blue LED chip.
The white light emitting diode device according to claim 1, wherein the phosphor comprises at least one selected from the group consisting of a yellow phosphor, a green phosphor and a red phosphor.

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