JP2018141814A - Color correction filter and display device using the same - Google Patents

Abstract

When a white LED has three light emission peaks, the color reproducibility is poor because the light emission peaks of the respective colors are not sufficiently separated. To provide an inexpensive color correction film that efficiently separates green and red and improves color reproducibility, and a display device using the same. An invention made to solve the above problems is a color correction filter applied to a display device using a white LED as a backlight, and the white LED is a white LED having three emission peaks. Achieved by a color correction filter that is a three-wavelength white LED that combines three LEDs of red, green, and blue light emission to make a white light source, and the film has an absorption maximum in a wavelength region between 550 nm and 650 nm Is done. [Selection figure] None

Description

  The present invention relates to a color correction filter for a three-wavelength white LED using a combination of three LEDs emitting red, green, and blue light as a white light source, and a display device using the same.

Recently, an LED (Light Emitting Diode) having a wide color reproducibility area has been used as a light source of a backlight for a backlight of a liquid crystal display device used in a color television or a notebook personal computer.
As typical methods for white LED light sources, (1) a three-wavelength white LED type that combines three LEDs of red, green, and blue light emission to form a white light source, and (2) a near-ultraviolet or violet light-emitting LED There are three types: a three-wavelength white LED type composed of red, green and blue light emitting phosphors, and (3) a two-wavelength white LED type composed of a blue light emitting LED and a yellow light emitting phosphor. The method (1) has a wider color reproducibility area than a liquid crystal display device using a fluorescent lamp, but it is not preferable in terms of power consumption and manufacturing cost because it uses three LEDs. In the case of the method (2), there is a feature that a beautiful white color can be obtained by the same light emission method as that of the three-wavelength fluorescent lamp, but there is a problem that the light emission efficiency is poor. The method (3) has the highest light emission efficiency among the above three methods and is advantageous for power consumption, but has a problem of poor color reproducibility. A type of a three-wavelength white LED having a good color reproducibility is reported in Patent Document 1.
Since the two-wavelength white LED realizes white light by combining the blue light of the blue light emitting LED and a phosphor emitting yellow, which is a complementary color, the color reproducibility is poor because green and red cannot be separated. It has been proposed to provide an inexpensive color correction filter that efficiently separates green and red and improves color reproducibility, and a liquid crystal display device using the same (Patent Document 2).

  Although it is said that the color reproducibility is good for the type of the three-wavelength white LED, further color reproducibility is required because green and red are not sufficiently separated.

JP 2010-32820 A JP 2012-27298 A

When the white LED has three emission peaks, the color reproducibility is poor because the emission peaks of the respective colors are not sufficiently separated. In particular, in a three-wavelength white LED using a red light source, a green light source, and a blue light emitting LED as a white light source, the color reproducibility is poor because green and red are not sufficiently separated. It is an object of the present invention to provide an inexpensive color correction film that efficiently separates green and red and improves color reproducibility and a display device using the same.

The invention made to solve the above problems is
A color correction filter applied to a display device using a white LED as a backlight, wherein the white LED is a white LED having three emission peaks, and a white light source is formed by combining three LEDs of red, green, and blue light emission. Which is achieved by a color correction filter characterized in that the film has an absorption maximum in the wavelength region between 550 nm and 650 nm.

  Another invention made to solve the above problems is achieved by a display device having the color correction filter.

  The present invention has been made based on the above circumstances, and an object thereof is a color correction filter applied to a display device using a white LED as a backlight, and the white LED is red, green. This is a three-wavelength white LED that combines three blue light emitting LEDs to form a white light source, and can be realized by a color correction filter characterized in that the filter has an absorption maximum in a wavelength region between 550 nm and 650 nm. it can.

In the color correction filter of the present invention, the substrate constituting the filter may be a single layer or a multilayer. When the base material is a single layer, for example, a base material made of a transparent resin substrate containing a dye having an absorption maximum value in a wavelength region between 420 nm and 520 nm can be mentioned. In the case of a multilayer, for example, an overcoat made of a curable resin containing a dye having an absorption maximum in a wavelength region between 420 nm and 520 nm on a support such as a glass support or a base resin support. A resin layer such as an overcoat layer made of a curable resin or the like on a base material on which a transparent resin layer such as a layer is laminated, a transparent resin substrate including a dye having an absorption maximum in a wavelength region between 420 nm and 520 nm A laminated base material can be exemplified. In the wavelength region between 420 nm and 520 nm, from the viewpoints of manufacturing cost and ease of optical property adjustment, and further, it is possible to achieve the scratch-removing effect of the resin support and transparent resin substrate and the improvement of scratch resistance of the base material. A substrate in which a resin layer such as an overcoat layer made of a curable resin is laminated on a transparent resin substrate containing a dye having an absorption maximum value is particularly preferable.
The transparent resin layer and the transparent resin substrate laminated on a resin support, a glass support, or the like can be formed using a transparent resin. As transparent resin used for the said base material, 1 type may be individual and 2 or more types may be sufficient.
Such a resin is not particularly limited as long as it does not impair the effects of the present invention. For example, high-temperature vapor deposition is performed at a vapor deposition temperature of 100 ° C. or higher while ensuring thermal stability and filter formability. In order to obtain a filter capable of forming a dielectric multilayer film, a resin having a glass transition temperature (Tg) of preferably 110 to 380 ° C, more preferably 110 to 370 ° C, and still more preferably 120 to 360 ° C. . Further, it is particularly preferable that the glass transition temperature of the resin is 140 ° C. or higher because a filter film capable of depositing the dielectric multilayer film at a higher temperature can be obtained.

  Further, as the resin, the total light transmittance (JIS K7105) at a thickness of 0.1 mm is preferably 75 to 95%, more preferably 78 to 95%, and particularly preferably 80 to 95%. The resin which is can be used. When the total light transmittance is within such a range, the obtained substrate exhibits good transparency as an optical filter.

  Examples of the resin include cyclic polyolefin resins, aromatic polyether resins, polyimide resins, fluorene polycarbonate resins, fluorene polyester resins, polycarbonate resins, polyamide (aramid) resins, polyarylate resins, polysulfones. Resin, polyethersulfone resin, polyparaphenylene resin, polyamideimide resin, polyethylene naphthalate (PEN) resin, fluorinated aromatic polymer resin, (modified) acrylic resin, epoxy resin, allyl Examples include ester-based curable resins and silsesquioxane-based ultraviolet curable resins.

(1) Cyclic olefin resin The cyclic olefin resin is at least one selected from the group consisting of a monomer represented by the following formula (X ₀ ) and a monomer represented by the following formula (Y ₀ ). A resin obtained from one monomer or a resin obtained by hydrogenating the resin obtained above as required is preferred.

In the formula (X ₀ ), R ^{x1 to} R ^x4 each independently represents an atom or group selected from the following (i) to (viii), and k ^x , ^mx and p ^x are each independently 0 or positive Represents an integer.
(I) a hydrogen atom (ii) a halogen atom (iii) a trialkylsilyl group (iv) a substituted or unsubstituted carbon atom having 1 to 30 carbon atoms having a linking group containing an oxygen atom, a sulfur atom, a nitrogen atom or a silicon atom Hydrogen group (v) substituted or unsubstituted hydrocarbon group having 1 to 30 carbon atoms (vi) polar group (excluding (iv))
(Vii) R ^x1 and R ^x2 or R ^x3 and R ^x4 represent an alkylidene group formed by bonding to each other, and R ^{x1 to} R ^x4 not involved in the bonding are each independently the above (i) to Represents an atom or group selected from (vi);
(Viii) R ^x1 and R ^x2 or R ^x3 and R ^x4 represent a monocyclic or polycyclic hydrocarbon ring or heterocyclic ring formed by bonding to each other, and R ^{x1 to} R ^x4 not participating in the bond Each independently represents an atom or group selected from the above (i) to (vi), or represents a monocyclic hydrocarbon ring or heterocyclic ring formed by bonding R ^x2 and R ^x3 to each other. R ^{x1 to} R ^x4 not involved in the bond each independently represent an atom or group selected from the above (i) to (vi).

Wherein (Y _0), R ^y1 and R ^y2 are either each independently a represents an atom or group selected from (i) ~ (vi), represents the following (ix), k ^y and p ^y are each Independently represents 0 or a positive integer.
(Ix) R ^y1 and R ^y2 each represent a monocyclic or polycyclic alicyclic hydrocarbon, aromatic hydrocarbon or heterocyclic ring formed by bonding to each other.

(2) Aromatic polyether resin The aromatic polyether resin is at least one selected from the group consisting of a structural unit represented by the following formula (1) and a structural unit represented by the following formula (2). It preferably has a structural unit.

In formula (1), R < ¹ > -R < ⁴ > shows a C1-C12 monovalent organic group each independently, and ad shows the integer of 0-4 each independently.

Wherein (2), R ¹ to R ⁴ and a~d are the same as R ¹ to R ⁴ and a~d each independently the formula (1), Y is a single bond, -SO ₂ -, Or> C = O, R ⁷ and R ⁸ each independently represent a halogen atom, a monovalent organic group having 1 to 12 carbon atoms or a nitro group, and g and h each independently represents 0 to 4 Represents an integer, and m represents 0 or 1. However, when m is 0, R ⁷ is not a cyano group.

  The aromatic polyether-based resin may further include at least one structural unit selected from the group consisting of a structural unit represented by the following formula (3) and a structural unit represented by the following formula (4). preferable.

In formula (3), R ⁵ and R ⁶ each independently represent a monovalent organic group having 1 to 12 carbon atoms, Z represents a single bond, —O—, —S—, —SO ₂ —,> C = O, -CONH-, -COO- or a divalent organic group having 1 to 12 carbon atoms, e and f each independently represent an integer of 0 to 4, and n represents 0 or 1.

In the formula (4), R ⁷ , R ⁸ , Y, m, g and h are each independently synonymous with R ⁷ , R ⁸ , Y, m, g and h in the formula (2), and R ⁵ , R ⁶ , Z, n, e and f are independently the same as R ⁵ , R ⁶ , Z, n, e and f in the formula (3).

(3) Polyimide-based resin The polyimide-based resin is not particularly limited as long as it is a polymer compound containing an imide bond in a repeating unit. For example, in JP-A-2006-199945 and JP-A-2008-163107 It can be synthesized by the method described.

(4) Fluorene polycarbonate-based resin The fluorene polycarbonate-based resin is not particularly limited and may be any polycarbonate resin including a fluorene moiety. For example, the fluorene polycarbonate-based resin can be synthesized by a method described in JP-A-2008-163194. it can.

(5) Fluorene polyester-based resin The fluorene polyester-based resin is not particularly limited as long as it is a polyester resin containing a fluorene moiety, and is described in, for example, JP 2010-285505 A or JP 2011-197450 A. It can be synthesized by the method.

(6) Fluorinated aromatic polymer-based resin The fluorinated aromatic polymer-based resin is not particularly limited, and includes an aromatic ring having at least one fluorine, an ether bond, a ketone bond, a sulfone bond, an amide bond, and an imide. Any polymer containing a repeating unit containing at least one bond selected from the group consisting of a bond and an ester bond may be used. For example, the polymer can be synthesized by the method described in JP-A-2008-181121.

(7) Commercially available products Examples of commercially available transparent resins that can be used in the present invention include the following commercially available products. Examples of commercially available cyclic olefin-based resins include Arton manufactured by JSR Corporation, ZEONOR manufactured by Zeon Corporation, APEL manufactured by Mitsui Chemicals, Inc., and TOPAS manufactured by Polyplastics Corporation. Examples of commercially available polyethersulfone resins include Sumika Excel PES manufactured by Sumitomo Chemical Co., Ltd. Examples of commercially available polyimide resins include Neoprim L manufactured by Mitsubishi Gas Chemical Co., Ltd. Examples of commercially available polycarbonate resins include Pure Ace manufactured by Teijin Limited. Examples of commercially available fluorene polycarbonate resins include Iupizeta EP-5000 manufactured by Mitsubishi Gas Chemical Co., Ltd. Examples of commercially available fluorene polyester resins include OKP4HT manufactured by Osaka Gas Chemical Co., Ltd. As a commercial product of acrylic resin, there can be cited NIPPON CATALYST ACRYVIEWER Co., Ltd. Examples of commercially available silsesquioxane UV curable resins include Silplus manufactured by Nippon Steel Chemical Co., Ltd.
<Dye>
The dyes used in the present invention are described in detail below.
<Dye having absorption maximum in wavelength region between 550 nm and 650 nm>
The wavelength region between 550 nm and 650 nm is a wavelength region between the green and red LEDs, and the color reproducibility can be improved by increasing the absorption in the wavelength region between 550 nm and 650 nm.
Specific examples of the dye having an absorption maximum in the wavelength region between 550 nm and 650 nm are selected from the group consisting of squarylium dyes, cyanine dyes, subphthalocyanine dyes, perylene dyes, and porphyrin dyes. Mention may be made of pigments.
<Dye having absorption maximum in wavelength region between 420 nm and 520 nm>
The wavelength region between 420 nm and 520 nm is a wavelength region between the blue and green LEDs, and the color reproducibility can be improved by increasing the absorption in the wavelength region between 420 nm and 520 nm.
Specific examples of the dye having an absorption maximum in a wavelength region between 420 nm and 520 nm include semisquarium dye, cyanine dye, styryl dye, phenazine dye, pyridomethene-boron complex dye, and pyrazine- Examples thereof include a dye selected from the group consisting of boron complex dyes.
<Dye having absorption maximum in wavelength region of 680 nm or more>
The wavelength region of 680 nm or more is a wavelength region corresponding to the bottom of the red light emission of the white LED, and the color reproducibility can be improved by increasing the absorption in this wavelength region.
As a dye capable of achieving such absorption characteristics, a dye having an absorption maximum wavelength of 680 nm to 800 nm is preferable, and specific examples include squarylium dye, phthalocyanine dye, cyanine dye, hexaphyrin dye, and croconium dye. The pigment | dye chosen from the group which consists of can be mentioned.

  Examples of such a dye are described in JP2012-8532A, JP2013-218312A, JP2015-040895A, WO2013-054864, WO2015-025779, and the like. A dye capable of absorbing near infrared rays can be preferably used.

Examples of the dielectric multilayer film that can be used in the present invention include an aluminum vapor-deposited film, a noble metal thin film, a resin film in which metal oxide fine particles containing indium oxide as a main component and containing a small amount of tin oxide are dispersed, or having a different refractive index. Examples include dielectric multilayer films in which materials are alternately stacked.

  In the present invention, the dielectric multilayer film may be provided on one side or both sides of the resin substrate. When it is provided on one side, it is excellent in production cost and manufacturability, and when it is provided on both sides, it is possible to obtain an optical filter having high strength and less warpage.

    Among the dielectric multilayer films, a dielectric multilayer film in which materials having different refractive indexes are alternately stacked is more preferable.

As materials having different refractive indexes, materials having a refractive index range of 1.2 to 2.5 are usually selected. Examples of such materials include titanium oxide, zirconium oxide, tantalum pentoxide, niobium pentoxide, lanthanum oxide, yttrium oxide, zinc oxide, zinc sulfide, indium oxide, and the like as main components, and titanium oxide, tin oxide, and / or Alternatively, cerium oxide or the like containing a small amount (for example, 0 to 10% with respect to the main component), silica, alumina, lanthanum fluoride, magnesium fluoride, sodium hexafluoride sodium, or the like can be given.
The method for laminating materials having different refractive indexes is not particularly limited as long as a dielectric multilayer film in which these material layers are laminated is formed. For example, a dielectric multilayer film in which materials having different refractive indexes are alternately stacked is directly formed on the resin substrate by CVD, sputtering, vacuum deposition, ion-assisted deposition, or ion plating. be able to.
As the materials having different refractive indexes, two or more different materials may be alternately stacked, or the same materials having different refractive indexes may be alternately stacked by changing the film formation conditions.

  The thickness of each layer of materials having different refractive indexes is usually preferably from 0.1λ to 0.5λ, where λ (nm) is the wavelength to be blocked. When the thickness is within this range, the product of the refractive index (n) and the film thickness (d) (n × d) is calculated by λ / 4, and the thickness of each layer of the material having a different refractive index is obtained. The values are almost the same, and there is a tendency that the blocking and transmission of a specific wavelength can be easily controlled based on the relationship between the optical characteristics of reflection and refraction.

  In addition, the total number of layers of the high refractive index material layer and the low refractive index material layer in the dielectric multilayer film is 5 to 80 layers, preferably 10 to 60 layers.

  Further, the smaller the difference in refractive index between materials having different refractive indexes, the smaller the band that can be cut, which is preferable.

In addition, if the substrate is warped when the dielectric multilayer film is formed, the dielectric multilayer film is formed on both surfaces of the substrate or the substrate dielectric multilayer film is formed to solve this problem. A method of irradiating the surface with electromagnetic waves such as ultraviolet rays can be used. In addition, when irradiating electromagnetic waves, you may irradiate during formation of a dielectric multilayer, and you may irradiate separately after formation.
<Display device>
A display element provided with the said cured film for display elements is also suitably contained in this invention. As a method for manufacturing a display element, first, a pair (two) of transparent substrates having a transparent conductive film (electrode) on one side is prepared, and the radiation-sensitive resin composition is formed on the transparent conductive film of one of the substrates. Is used to form a spacer or a protective film or both in accordance with the method described above. Subsequently, an alignment film having liquid crystal alignment ability is formed on the transparent conductive film and the spacer or protective film of these substrates. These substrates are arranged facing each other with a certain gap (cell gap) so that the liquid crystal alignment direction of each alignment film is orthogonal or antiparallel, with the surface on which the alignment film is formed inside. A liquid crystal is filled in the cell gap defined by the surface of the substrate (alignment film) and the spacer, and the filling hole is sealed to constitute a liquid crystal cell. Then, the display element of the present invention is bonded to both outer surfaces of the liquid crystal cell such that the polarizing direction is aligned or orthogonal to the liquid crystal alignment direction of the alignment film formed on one surface of the substrate. can get.

As another method, a pair of transparent substrates on which a transparent conductive film, an interlayer insulating film, a protective film, a spacer, or both, and an alignment film are formed are prepared in the same manner as described above. After that, along the edge of one substrate, an ultraviolet curable sealant is applied using a dispenser, and then the liquid crystal is dropped in the form of fine droplets using a liquid crystal dispenser, and the two substrates are bonded together under vacuum. . Then, both the substrates are sealed by irradiating the sealing agent part with ultraviolet rays using a high-pressure mercury lamp. Finally, the display device of the present invention is obtained by attaching polarizing plates to both outer surfaces of the liquid crystal cell.
The color correction filter obtained in the present invention may be disposed on the backlight of the LED light source, and the color reproducibility of the display device can be improved by being disposed above.

  Below, the synthesis example of resin used by this invention is explained in full detail.

<Synthesis example>
<Resin synthesis example 1>
8-methyl-8-methoxycarbonyltetracyclo represented by the following formula (a) [4.4.0.1 ^2,5 . 1 ^7,10 ] Dodec-3-ene (hereinafter also referred to as “DNM”) 100 parts, 18 parts of 1-hexene (molecular weight regulator) and 300 parts of toluene (solvent for ring-opening polymerization reaction) were substituted with nitrogen. The vessel was charged and the solution was heated to 80 ° C. Next, 0.2 parts of a toluene solution of triethylaluminum (0.6 mol / liter) as a polymerization catalyst and a toluene solution of methanol-modified tungsten hexachloride (concentration 0.025 mol / liter) were added to the solution in the reaction vessel. 9 parts was added and this solution was heated and stirred at 80 ° C. for 3 hours to cause a ring-opening polymerization reaction to obtain a ring-opening polymer solution. The polymerization conversion rate in this polymerization reaction was 97%.

1,000 parts of the ring-opening polymer solution thus obtained was charged into an autoclave, and 0.12 part of RuHCl (CO) [P (C ₆ H ₅ ) ₃ ] ₃ was added to the ring-opening polymer solution. Then, the hydrogenation reaction was performed by heating and stirring for 3 hours under the conditions of hydrogen gas pressure of 100 kg / cm ² and reaction temperature of 165 ° C.

After cooling the obtained reaction solution (hydrogenated polymer solution), the hydrogen gas was released. This reaction solution was poured into a large amount of methanol to separate and recover the coagulated product, and dried to obtain a hydrogenated polymer (hereinafter also referred to as “resin A”). The obtained resin A had a number average molecular weight (Mn) of 32,000, a weight average molecular weight (Mw) of 137,000, and a glass transition temperature (Tg) of 165 ° C.
<Example 1>
In a container, 100 parts by weight of the resin A obtained in Synthesis Example 1, a squarylium-based dye represented by the following formula (A) as a dye having an absorption maximum in a wavelength region between 550 nm and 650 nm (absorption maximum wavelength in dichloromethane) (576 nm) 0.04 parts by mass and further methylene chloride were added to obtain a solution (ex1) having a resin concentration of 20% by weight. Subsequently, the obtained solution was cast on a smooth glass plate, dried at 20 ° C. for 8 hours, and then peeled off from the glass plate. The peeled coating film was further dried at 100 ° C. under reduced pressure for 8 hours to obtain a color correction filter composed of a resin substrate having a thickness of 0.1 mm, a length of 60 mm, and a width of 60 mm.

(A)
<Comparative Example 1>
In the same manner as in Example 1, a solution (ex1) having a resin concentration of 20% by weight not containing a dye having an absorption maximum in each wavelength region was obtained. Subsequently, the obtained solution was cast on a smooth glass plate, dried at 20 ° C. for 8 hours, and then peeled off from the glass plate. The peeled coating film was further dried at 100 ° C. under reduced pressure for 8 hours to obtain a substrate having a thickness of 0.1 mm, a length of 60 mm, and a width of 60 mm.

  The spectral transmittance of this substrate was measured, and the transmittance at the absorption maximum wavelength, the absorption maximum wavelength, and the transmittance in the visible light wavelength region were determined. The results are shown in Table 1.

<Evaluation of color reproducibility>
The filters obtained in Example 1 and Comparative Example 1 were evaluated for color reproducibility.

  It was bonded to the front of a commercially available liquid crystal display device (trade name, LC-15B1-S, manufactured by Sharp Corporation) that does not have the filter and pigment obtained in Example 1 and Comparative Example 1.

    The chromaticity coordinates at the center of the screen of this liquid crystal display device are measured with a spectral radiance meter (CS-2000 type, manufactured by Konica Minolta Sensing Co., Ltd.) to obtain the chromaticity coordinates of red, green, and blue. The area of the triangle obtained by tying was obtained.

    The color reproducibility of the liquid crystal display device with the color correction filter installed is the triangular area obtained by connecting the chromaticity coordinates, and the triangular area obtained by connecting the chromaticity coordinates of the liquid crystal display device without the color correction filter installed. Evaluation was made by comparing the area as 100. In addition, it can be considered that a color reproduction range is so large that the area of this triangle is large. The results are shown in Table 4.

    From Table 1, it was found that the color reproducibility can be improved by installing the color correction filter obtained in Example 1 as compared with the filter of Comparative Example 1.

    It can be considered that the above results are brought about by absorbing unnecessary light in the liquid crystal display device by the color correction filter of the present invention. For this reason, it is considered that the color purity and contrast of the liquid crystal display device are also improved.

Claims (12)

  A color correction filter applied to a display device using a white LED as a backlight, wherein the white LED is a white LED having three emission peaks, and the film has an absorption maximum in a wavelength region between 550 nm and 650 nm. A color correction filter comprising: The color correction filter according to claim 1, comprising at least one dye selected from the group consisting of a squarylium dye, a cyanine dye, a subphthalocyanine dye, a perylene dye, and a porphyrin dye. filter.   The color correction filter according to claim 1, wherein the color correction filter further includes a dye having an absorption maximum value in a wavelength region between 420 nm and 520 nm. The color correction filter according to claim 3 is at least one selected from the group consisting of semi-squarylium dyes, cyanine dyes, styryl dyes, phenazine dyes, pyridomethene-boron complex dyes, and pyrazine-boron complex dyes. The color correction filter according to any one of claims 1 to 3, further comprising a pigment.   The color correction filter according to claim 1, further comprising a dye having an absorption maximum value in a wavelength region of 680 nm or more. 6. The color correction filter according to claim 1, wherein the color correction filter has at least one dye selected from the group consisting of a squarylium dye, a phthalocyanine dye, a cyanine dye, a hexaphyrin dye, and a croconium dye. The color correction filter according to any one of the above. The color correction filter according to any one of claims 1 to 6, wherein the color correction filter is formed of a transparent resin substrate. The color correction filter according to claim 1, wherein the color correction filter has a dielectric multilayer film on a transparent resin substrate. 9. The color correction filter according to claim 7, wherein the transparent resin substrate is a norbornene-based resin substrate.   A color correction filter comprising: the dye according to claim 2 selected from claim 2, claim 4, and claim 6; and the dielectric multilayer film according to claim 8.   The display apparatus using the color correction filter as described in any one of Claims 1-10.   11. The white LED according to claim 1, wherein the white LED is a three-wavelength white LED that combines three LEDs of red, green, and blue light emission to form a white light source. The described color correction filter.