CN116209927A

CN116209927A - Optical filter material, display module and manufacturing method thereof

Info

Publication number: CN116209927A
Application number: CN202180027943.1A
Authority: CN
Inventors: 李威; 骆欣涛
Original assignee: Huawei Technologies Co Ltd
Current assignee: Huawei Technologies Co Ltd
Priority date: 2021-09-30
Filing date: 2021-09-30
Publication date: 2023-06-02
Also published as: WO2023050365A1

Abstract

The application provides a light filtering material, a display module and a manufacturing method thereof. The filter material comprises: a substrate, and pigments and scattering particles dispersed within the substrate. The pigment is used for absorbing light rays of a blue light wave band, and the scattering particles are used for scattering the light rays of the blue light wave band, so that the scattering degree of the light rays of the blue light wave band in the filter material is larger than the scattering degree of the light rays of the red light wave band and the green light wave band in the filter material. By adding the scattering particles into the filter material, the scattering particles can increase the scattering degree of the light rays of the blue light wave band so as to increase the transmission optical path of the light rays of the blue light wave band in the filter material, and the transmission optical path of the light rays of the red light wave band and the light rays of the green light wave band in the filter material can not be influenced, so that the transmittance of the light rays of the red light wave band and the light rays of the green light wave band can not be obviously reduced. Therefore, the absorptivity of the light in the blue light band can be increased without affecting the transmittance of the light in the red light band and the green light band.

Description

Optical filter material, display module and manufacturing method thereof

Technical Field

The application relates to the technical field of display, in particular to a light filtering material, a display module and a manufacturing method thereof.

Background

The filter film refers to a film layer that attenuates light intensity or changes spectral composition. The main uses are to reduce or increase the color temperature, change the wavelength, shade unwanted light, change the color of light, etc. The color filter film plays a very important role in display devices such as organic light emitting diode (organic light emitting diode, OLED) display modules and the like.

In the related art, a color filter film may be disposed in the display module to enable the display module to implement color display. In some display modules, a yellow filter film can be further arranged, and the yellow filter film can be used as a compensation filter for filtering out redundant blue light in the display module, so that the display module has a wider color gamut. However, the yellow filter film in the related art can not affect the transmittance of the red-green light band (450-780 nm) while improving the spectral absorptivity of the blue light band, so that the absorptivity of the blue light band and the transmittance of the red-green light band of the display module cannot be both achieved, and the overall power consumption of the display module is adversely affected.

Disclosure of Invention

The application provides a light filtering material, a display module and a manufacturing method thereof, which are used for solving the influence of a yellow light filtering material on the transmittance of red-green light wave bands.

In a first aspect, embodiments of the present application provide a filter material that may include: the light-emitting device comprises a substrate, and pigment and scattering particles dispersed in the substrate, wherein the pigment is used for absorbing light rays of a blue light wave band, and the scattering particles are used for scattering the light rays of the blue light wave band, so that the scattering degree of the light rays of the blue light wave band in the filter material is greater than the scattering degree of the light rays of a red light wave band and a green light wave band in the filter material.

In particular implementations, the degree of scattering of light in each colorband in the filter may be characterized by detecting the haze of light in each colorband, with greater haze indicating a greater degree of scattering of light. Alternatively, the degree of scattering of the light of each colorband in the filter may be reflected by measuring the transmission optical path length of the light of each colorband, where a longer transmission optical path length of the light indicates a higher degree of scattering of the light.

In this embodiment of the application, through adding scattering particles in the filter material, scattering particles can increase the scattering degree of the light of the blue light wave band in the filter material to increase the transmission optical path of the light of the blue light wave band in the filter material, equivalently increased the concentration of pigment in the filter material, can increase the absorptivity of the filter material to the light of the blue light wave band. And because the scattering particles have no scattering effect or weak scattering effect on the light rays of the red light wave band and the green light wave band, the scattering particles can not influence the transmission optical path of the red light wave band and the green light wave band in the filter material, namely the transmittance of the light rays of the red light wave band and the green light wave band can not be obviously reduced. Therefore, the filter material provided by the embodiment of the application can increase the absorptivity of the light rays in the blue light wave band on the basis of not affecting the transmittance of the light rays in the red light wave band and the green light wave band. In addition, since the filter material has less influence on the light rays of the red light band and the green light band, the absorptivity of the light rays of the blue light band can be further improved by increasing the thickness of the filter material or increasing the concentration of the pigment.

In the embodiments of the present application, the substrate may be a liquid, a colloid, or a solid. When the substrate is liquid or colloid, the substrate mixed with pigment and scattering particles can be coated on the surface of the object, and after curing, a filter layer is formed on the surface of the object. When the substrate is solid, the substrate mixed with the pigment and the scattering particles may serve as a filter layer, which may be directly attached to the surface of the object. In addition, the formed filter layer may be subjected to a patterning process such that the filter layer covers a specific region of the surface of the body. In practical applications, the substrate may be made of an organic resin material, or the substrate may be made of other materials, which is not limited herein.

In this embodiment, when the substrate is liquid or colloid, the pigment and the scattering particles may be uniformly mixed in the substrate by a physical manner, for example, a mechanical stirring manner may be adopted, and by adjusting physical parameters such as viscosity, the pigment and the scattering particles may be uniformly mixed in the substrate, so that stability of a system formed by the substrate, the pigment and the scattering particles is better. In addition, the pigment and the scattering particles can be uniformly mixed in the substrate by adopting a chemical mode, and optionally, the filter material can further comprise: a dispersant dispersed in the substrate, the dispersant being capable of adjusting the degree of dispersion of the scattering particles in the substrate. Pigment, scattering particles and dispersing agent are added into a base material, the dispersing agent can be wrapped on the surface of the scattering particles, the scattering particles can not be gathered together, and the dispersing agent has the property of hydrophilism and lipophilicity, so that one end of the dispersing agent can be connected with the scattering particles, and the other end of the dispersing agent can be connected with the base material, the effect of adjusting the dispersion degree of the scattering particles in the base material is achieved, and the pigment and the scattering particles are uniformly mixed in the base material. Alternatively, the dispersant may be an organofunctional group, or the dispersant may be other materials, not limited herein.

In particular implementations, a laser diffraction particle size analyzer (laser diffraction particle diffusion) can be used to detect the degree of scattering particles dispersed in the substrate. The degree of scattering particles dispersed in the substrate can be indirectly reflected by the relationship between the median particle diameter (D50) and the true particle diameter. The median particle diameter may represent a particle diameter value corresponding to a cumulative distribution percentage of the scattering particles in the base material of 50%, and represents 50% of the scattering particles having a particle diameter larger than the particle diameter value and 50% of the scattering particles having a particle diameter smaller than the particle diameter value. The true particle size is the average of all scattering particles before placement into the substrate. If the median particle size of the scattering particles within the substrate is similar to the true particle size, a relatively uniform dispersion of the scattering particles in the substrate is indicated. If the median particle size of the scattering particles within the substrate is much larger than the true particle size, this means that there are many scattering particles in the substrate that are clustered together, and that the scattering particles in the substrate are poorly dispersed. In the embodiment of the application, the difference between the median particle diameter and the true particle diameter of the scattering particles in the substrate is smaller than 25%, so that the scattering particles can be uniformly dispersed in the substrate.

In specific implementations, the pigment may be an organic material or an inorganic material, or other materials may be used as the pigment, which is not limited herein. In order to make the absorptivity of the filter material to light in the blue band high, the pigment concentration may be set to be more than 10%.

In some embodiments of the present application, the scattering particles may be made of transparent materials. Alternatively, the scattering particles may include: silica, aluminum oxide, titanium oxide, zirconium oxide, indium tin oxide, antimony doped tin dioxide, organosiloxane, polystyrene, polyamide or polymethyl methacrylate. Other materials having a scattering effect may be used as the scattering particles, and are not limited herein.

In practical applications, in the above-mentioned filter material provided in the embodiments of the present application, the diameter of the scattering particles may be smaller than 3 μm, for example, the diameter of the scattering particles may be smaller than 1 μm. Thus, the scattering particles can play a role in Mie scattering (belonging to one of Rayleigh scattering) so that the scattering degree of light rays in the blue light wave band is higher than that of light rays in the red light wave band and the green light wave band. Therefore, the scattering particles can make the transmission optical path of the light rays in the blue light wave band larger than the transmission optical path of the light rays in the red light wave band and the green light wave band when the light rays pass through the filter materials with the same thickness. That is, in the embodiment of the present application, by adding scattering particles with a diameter smaller than 3 μm to the substrate, absorption of light in the blue light band by the pigment in the filter material can be specifically increased, and absorption of light in the red light band and the green light band can be reduced. The light transmittance of the blue light wave band can be reduced on the basis that the light transmittance of the red light wave band and the green light wave band is not affected.

In embodiments of the present application, the scattering particles may be spherical in shape, although other shapes, such as ellipsoids or irregular shapes, are also possible. It will be appreciated that when the diameter of the scattering particles is non-spherical, the diameter of the scattering particles may be the distance between the two points of the scattering particles that are furthest apart.

In one possible implementation, the haze of the light in the blue band in the filter material is in the range of 30% -50%; the haze of the light rays in the green light wave band in the filter material is less than 20%, and the haze of the light rays in the red light wave band in the filter material is less than 10%. Therefore, the scattering degree of the filter material on the blue light wave band is higher, and the scattering degree of the filter material on the red light wave band and the green light wave band is lower.

In a second aspect, embodiments of the present application further provide a display module, where the display module may include: the light emitting device comprises a substrate, a plurality of light emitting devices positioned on the substrate, and a filter layer positioned on one side of the light emitting devices away from the substrate. The plurality of light emitting devices includes: the filter layer comprises a plurality of openings, each opening corresponds to one blue light emitting device, and the orthographic projection of the opening on the substrate and the orthographic projection of the corresponding blue light emitting device on the substrate have overlapping areas. The filter layer includes: a substrate, and pigments and scattering particles located within the substrate. Alternatively, the substrate in the filter layer may be solid, thereby stabilizing the structure of the filter layer. The pigment is used for absorbing light rays in the blue light band. The scattering particles are used for scattering light rays of a blue light wave band, so that the scattering degree of the light rays of the blue light wave band in the filter layer is larger than the scattering degree of the light rays of the red light wave band and the green light wave band in the filter layer.

In this embodiment of the application, through set up the filter layer in display module assembly, the filter layer can be on the basis that does not influence the transmissivity of the light of red light wave band and green light wave band, increases the absorptivity to the light of blue light wave band, therefore, unnecessary blue light wave band in the filter layer can filter out display module assembly to make display module assembly have wider colour gamut, promote display module assembly's whole display effect, and reduce display module assembly's consumption. In addition, the filter film layer is provided with an opening at the position corresponding to the blue light-emitting device, so that the blue light emitted by the blue light-emitting device can be directly emitted, and the redundant blue light wave band light rays in the red light-emitting device and the green light-emitting device are filtered, so that the normal display effect of the display module is not affected.

Alternatively, in the embodiment of the present application, the thickness of the filter layer may be in a range of 1 μm to 10 μm, so that the absorptivity of the filter layer in the blue band is high. Of course, the thickness of the filter layer may be greater than 10 μm or less than 1 μm, and may be set according to practical situations, and the thickness of the filter layer is not limited here. In addition, the absorption rate of the filter layer to the blue light band can be adjusted by adjusting the concentration of pigment and scattering particles in the filter layer. In the embodiment of the application, the thickness of the filter layer may be in a range of 1 μm to 10 μm, so that the filter layer can have higher absorptivity to a blue light wave band.

In an embodiment of the present application, the display module may be an organic light emitting diode display module. In the organic light emitting diode display module, the light emitting device may include an organic light emitting diode, which may include an anode, a cathode, and a light emitting layer between the anode and the cathode. The filter layer is arranged in the organic light-emitting diode display module, so that redundant light rays of a blue light wave band in the organic light-emitting diode display module can be filtered, and the filter layer is provided with an opening at a position corresponding to the blue light-emitting device, so that the blue light emitted by the blue light-emitting device can be directly emitted, and redundant light rays of the blue light wave band in the red light-emitting device and the green light-emitting device are filtered, and the problem of blue deviation in a screen-off state can be solved on the basis that normal display of the organic light-emitting diode display module is not affected.

In one possible implementation manner, the display module may further include: the packaging layer covers the plurality of light emitting devices, the touch control layer is positioned on one side of the packaging layer, which is away from the substrate, and the filter layer is positioned on one side of the touch control layer, which is away from the substrate. The packaging layer can block water vapor and oxygen and prevent the light-emitting device from being corroded by the water vapor and the oxygen. The touch control layer is arranged inside the display module, so that the display module has a touch control function. The filter layer is arranged on one side of the touch control layer, which is away from the substrate, so that the filter layer can be prevented from influencing the packaging effect of the light emitting device and the touch control effect of the filter layer can be prevented.

In addition, the organic light emitting diode display module may further include: and the optical adhesive layer is positioned between the polaroid and the filter layer. The reflectivity of the organic light-emitting diode display module can be reduced by arranging the polaroid, and the display contrast of the organic light-emitting diode display module is improved.

In another embodiment of the present application, the display module may be a micro light emitting diode display module, and in the micro light emitting diode display module, a color conversion method may be used to implement color display. In practice, the blue light emitting device may include: blue micro light emitting diode. The red light emitting device includes: the LED comprises a blue micro light emitting diode and a first color conversion layer covering the blue micro light emitting diode, wherein the first color conversion layer is used for converting light rays of a blue light wave band into light rays of a red light wave band. The green light emitting device includes: the light source comprises a blue micro light emitting diode and a second color conversion layer covering the blue micro light emitting diode, wherein the second color conversion layer is used for converting light rays of a blue light wave band into light rays of a green light wave band, and the light filtering layer is positioned on one side, away from the substrate, of the first color conversion layer and the second color conversion layer.

In this embodiment, through set up the filter layer in miniature emitting diode display module assembly to, the filter layer is located first color conversion layer and second color conversion layer and deviates from one side of substrate base plate, and the filter layer is equipped with the opening in the position department that corresponds to blue light emitting device. Therefore, the blue light emitted by the blue light emitting device can be directly emitted, and redundant blue light wave band light rays in the red light emitting device and the green light emitting device are filtered. Therefore, the filter layer can absorb blue light leaked from positions of the red light emitting device and the green light emitting device, so that the purity of emergent light of the red light emitting device and the green light emitting device is increased, and the display color gamut is improved. Therefore, the problems of blue shift in the screen-off state and color shift in the normal display process can be solved on the basis of not affecting the normal display of the micro light-emitting diode display module.

In a third aspect, an embodiment of the present application further provides a method for manufacturing a display module, where the method may include:

providing a substrate provided with a plurality of light emitting devices; wherein the plurality of light emitting devices includes: at least one red light emitting device, at least one green light emitting device, and at least one blue light emitting device;

A substrate mixed with pigment and scattering particles is adopted to manufacture a filter layer on a plurality of light-emitting devices; the pigment is used for absorbing light rays of a blue light wave band, and the scattering particles are used for scattering the light rays of the blue light wave band, so that the scattering degree of the light rays of the blue light wave band in the filter layer is greater than the scattering degree of the light rays of the red light wave band and the green light wave band in the filter layer;

and removing a part of the region in the filter layer to form an opening in a region corresponding to the blue light emitting device.

In this embodiment of the application, through forming the filter layer on light emitting device, the filter layer can be on the basis that does not influence the transmissivity of red light wave band and green light wave band's light, and the increase is to the absorptivity of blue light wave band's light, therefore, the unnecessary blue light wave band's light in the display module assembly can be filtered to the filter layer to make the display module assembly have wider colour gamut, promote display module assembly's whole display effect, and reduce display module assembly's consumption. In addition, an opening is formed in the region, corresponding to the blue light-emitting device, of the filter layer, so that blue light emitted by the blue light-emitting device can be directly emitted, and redundant blue light wave bands in the red light-emitting device and the green light-emitting device are filtered, so that the normal display effect of the display module is not affected.

In some embodiments of the present application, the above-mentioned use of a filter material, the above-mentioned use of a substrate mixed with pigment and scattering particles, to fabricate a filter layer over a plurality of light emitting devices, may include:

providing a filter layer formed by a substrate mixed with pigment and scattering particles;

the filter layer is attached over the plurality of light emitting devices.

When the base material in the filter material is solid, the base material mixed with pigment and scattering particles can be used as a filter layer, and the filter layer can be directly attached to the light-emitting device, so that the manufacturing process is simpler.

In other embodiments of the present application, the above-mentioned manufacturing of a filter layer on a plurality of light emitting devices using a substrate mixed with pigment and scattering particles may include:

mixing pigments and scattering particles in a liquid or colloidal state of a substrate;

coating a substrate mixed with pigment and scattering particles over a plurality of light emitting devices;

the substrate coated over the plurality of light emitting devices is cured to obtain a filter layer.

The filter layer is formed on the light-emitting device by adopting a coating process and a curing process, and the manufacturing process is more compatible with the manufacturing process of other film layers in the display module, so that the manufacturing cost is saved.

In one possible implementation, the pigment and scattering particles may be uniformly mixed within the substrate in the following manner:

mode one: the pigment and the scattering particles may be homogeneously mixed in the substrate by physical means. The pigment and the scattering particles can be placed in the base material, and the pigment and the scattering particles are uniformly dispersed in the base material by adopting a mechanical stirring mode.

Mode two: the pigment and the scattering particles may be chemically mixed homogeneously in the substrate. Placing a pigment, scattering particles and a dispersing agent in a substrate; wherein the dispersing agent is used for adjusting the dispersion degree of the scattering particles in the substrate.

The description of the technical effects that may be provided by any one of the possible designs in the above manufacturing method may refer to the description of the technical effects that may be provided by any one of the possible designs in the above first aspect or the second aspect, and the repetition is omitted.

It will be appreciated that the data in each of the above possible implementations of the present application, such as, for example, data of median particle diameter and true particle diameter of the scattering particles, concentration of pigment, diameter of the scattering particles, haze of each color band, thickness of the filter layer, etc., are all understood to be within the scope defined in the present application for values within engineering measurement errors at the time of measurement.

Drawings

FIG. 1a is a schematic diagram of a visible spectrum of a yellow filter material in the related art;

FIG. 1b is an enlarged partial schematic view of the dashed box Q1 in FIG. 1 a;

FIG. 1c is an enlarged partial schematic view of the dashed box Q2 in FIG. 1 a;

fig. 2 is a schematic structural diagram of a filtering material according to an embodiment of the present disclosure;

FIG. 3 is a schematic illustration of the effect of particles of different diameters on the scattering properties of light;

FIG. 4 is a graph showing the relationship between haze and wavelength when the diameter of scattering particles is about 0.1. Mu.m;

FIG. 5 is a diagram showing the comparison of the filtering effect of a filter material without scattering particles and with scattering particles;

fig. 6 is a schematic structural diagram of a display module provided in an embodiment of the present application;

fig. 7 is another schematic structural diagram of a display module provided in an embodiment of the present application;

fig. 8 is a flowchart of a method for manufacturing a display module according to an embodiment of the present application.

Reference numerals:

10-a filter layer; 101-a substrate; 102-pigment; 103-scattering particles; 20-a substrate base; 21R-red light emitting device; 21G-green light emitting device; 21B-blue light emitting device; 211-blue micro light emitting diode; 212-a first color conversion layer; 213-a second color conversion layer; 22-an encapsulation layer; 23-a touch layer; 24-a polarizing layer; 25-an optical adhesive layer; 26-cover plate; light rays of Y1-blue light wave band; light in the Y2-green band; y3-light of red light wave band; u-opening.

Detailed Description

For the purpose of making the objects, technical solutions and advantages of the present application more apparent, the present application will be described in further detail with reference to the accompanying drawings.

It should be noted that the same reference numerals in the drawings of the present application denote the same or similar structures, and thus a repetitive description thereof will be omitted. The words expressing the positions and directions described in the present application are described by taking the drawings as an example, but can be changed according to the needs, and all the changes are included in the protection scope of the present application. The drawings of the present application are merely schematic representations, not to scale.

Fig. 1a is a schematic view of a visible light spectrum of a yellow filter in the related art, fig. 1b is a partially enlarged schematic view of a dashed box Q1 in fig. 1a, and fig. 1c is a partially enlarged schematic view of a dashed box Q2 in fig. 1 a. In the figure, a curve L1 is a visible light spectrum of a yellow filter material with a thickness h1, and a curve L2 is a visible light spectrum of a yellow filter material with a thickness h2, wherein h1 is smaller than h2. As shown in fig. 1a to 1c, the transmittance of the yellow filter material in the blue light band of 350nm to 480nm is low, that is, the absorptivity of the yellow filter material in the blue light band is high. However, if the thickness of the yellow filter is increased, for example, when the thickness of the yellow filter is increased from h1 to h2 in the figure, the curve changes from L1 to L2, and it is seen that the transmittance of the yellow filter in the blue light band is decreased, but at this time, the transmittance of the yellow filter in the red-green light band is also decreased. Therefore, the yellow filter material has an effect on the transmittance of the red-green light band (450 nm to 780 nm) while reducing the transmittance of the blue light band, and the larger the thickness of the yellow filter material is, the larger the effect of the yellow filter material on the transmittance of the red-green light band is.

Based on the above, in order to solve the influence of the yellow filter material on the transmittance of the red-green light wave band, the embodiment of the application provides a filter material, a display module and a manufacturing method thereof. The following detailed description refers to the accompanying drawings.

The optical filter material provided in the embodiment of the present application may be applied to a display module, for example, the optical filter material may be applied to an organic light emitting diode display module or a micro light emitting diode (micro light emitting diode, micro LED) display module, or the optical filter material may be applied to other types of display modules, which is not limited herein. The optical filter material can filter out redundant light rays in a blue light wave band in the display module to solve the problems of display color gamut reduction, screen color shift and the like of the display module caused by blue light leakage. The display module in the embodiment of the application can be applied to display equipment such as mobile phones, tablet computers, notebook computers and intelligent watches, and can enable the display equipment to have good display effect and user experience.

An embodiment of the present application provides a filter material, fig. 2 is a schematic structural diagram of the filter material provided in the embodiment of the present application, as shown in fig. 2, where the filter material in the embodiment of the present application may include: a base material 101, and a pigment 102 and scattering particles 103 dispersed in the base material 101. The light in the blue wavelength band is shown by an arrow Y1, and the pigment 102 can be used for absorbing the light Y1 in the blue wavelength band, wherein the light Y1 in the blue wavelength band is shown by an arrow Y1 changing from a solid line to a broken line, and is absorbed after passing through the pigment 102. The scattering particles 103 are used for scattering the light Y1 in the blue light band, so that the scattering degree of the light Y1 in the blue light band in the filter is greater than the scattering degree of the light in the red light band and the green light band in the filter, that is, the scattering particles 103 do not affect the transmission optical paths of the light in the red light band and the green light band in the filter.

In this embodiment of the present application, by adding the scattering particles 103 in the filter material, the scattering degree of the light Y1 in the blue light band in the filter material may be increased by the scattering particles 103, so as to increase the transmission optical path of the light Y1 in the blue light band in the filter material, which is equivalent to increasing the concentration of the pigment 102 in the filter material, and may increase the absorptivity of the filter material to the light Y1 in the blue light band. Moreover, since the scattering particles 103 have no scattering effect or weak scattering effect on the light rays of the red light wave band and the green light wave band, the scattering particles 103 do not influence the transmission optical paths of the red light wave band and the green light wave band in the filter material, that is, the transmittance of the light rays of the red light wave band and the green light wave band is not obviously reduced. Therefore, the filter material provided by the embodiment of the application can increase the absorptivity of the light Y1 in the blue light wave band on the basis of not affecting the transmittance of the light in the red light wave band and the green light wave band. In addition, since the filter material has less influence on the light rays of the red light band and the green light band, the absorptivity of the light ray Y1 of the blue light band can be further improved by increasing the thickness of the filter material or increasing the concentration of the pigment 102.

With continued reference to fig. 2, in embodiments of the present application, the substrate 101 may be a liquid, a gel, or a solid. When the substrate 101 is a liquid or a gel, the substrate 101 mixed with the pigment 102 and the scattering particles 103 may be coated on the surface of the object, and after curing, a filter layer may be formed on the surface of the object. When the base material 101 is solid, the base material 101 in which the pigment 102 and the scattering particles 103 are mixed may be used as a filter layer, and the filter layer may be directly attached to the surface of the object. In addition, the formed filter layer may be subjected to a patterning process such that the filter layer covers a specific region of the surface of the body. In practical applications, the substrate 101 may be made of an organic resin material, or the substrate 101 may be made of other materials, which is not limited herein.

In this embodiment, when the substrate 101 is a liquid or a colloid, the pigment 102 and the scattering particles 103 may be uniformly mixed in the substrate 101 by a physical method, for example, a mechanical stirring method may be adopted, and by adjusting physical parameters such as viscosity, the pigment 102 and the scattering particles 103 may be uniformly mixed in the substrate 101, so that stability of a system formed by the substrate 101, the pigment 102 and the scattering particles 103 is better. In addition, the pigment 102 and the scattering particles 103 may be uniformly mixed in the substrate 101 by chemical means, and optionally, the above-mentioned filter material may further include: a dispersant (not shown in fig. 2) dispersed within the substrate 101, the dispersant being capable of adjusting the degree of dispersion of the scattering particles 103 in the substrate 101. The pigment 102, the scattering particles 103 and the dispersing agent are added into the base material 101, the dispersing agent can be coated on the surface of the scattering particles 103, the scattering particles 103 can not be gathered together, and the dispersing agent has the properties of hydrophilicity and lipophilicity, so that one end of the dispersing agent can be connected with the scattering particles 103, and the other end of the dispersing agent can be connected with the base material 101, so that the effect of adjusting the dispersion degree of the scattering particles 103 in the base material 101 is achieved, and the pigment 102 and the scattering particles 103 are uniformly mixed in the base material 101. Alternatively, the dispersant may be an organofunctional group, or the dispersant may be other materials, not limited herein.

In specific implementations, the material of the pigment 102 may be an organic material or an inorganic material, or other materials may be used for the pigment 102, which is not limited herein. In order to make the absorptivity of the filter material to light in the blue band high, the concentration of the pigment 102 may be set to be more than 10%.

In some embodiments of the present application, the scattering particles may be made of transparent materials. Alternatively, the scattering particles may include: silica, aluminum oxide, titanium oxide, zirconium oxide, indium tin oxide, antimony doped tin dioxide, organosiloxane, polystyrene, polyamide or polymethyl methacrylate (polymethyl methacrylate, PMMA). Other materials having a scattering effect may be used as the scattering particles, and are not limited herein.

In practical applications, in the above-mentioned filter material provided in the embodiments of the present application, the diameter of the scattering particles may be smaller than 3 μm, for example, the diameter of the scattering particles may be smaller than 1 μm. Thus, the scattering particles can have the effect of Mie scattering (Mie scattering), which is one of Rayleigh scattering, so that the scattering degree of light rays in the blue light band is higher than that in the red light band and the green light band. Therefore, the scattering particles can make the transmission optical path of the light rays in the blue light wave band larger than the transmission optical path of the light rays in the red light wave band and the green light wave band when the light rays pass through the filter materials with the same thickness. That is, in the embodiment of the present application, by adding scattering particles with a diameter smaller than 3 μm to the substrate, absorption of light in the blue light band by the pigment in the filter material can be specifically increased, and absorption of light in the red light band and the green light band can be reduced. The light transmittance of the blue light wave band can be reduced on the basis that the light transmittance of the red light wave band and the green light wave band is not affected.

Fig. 3 is a schematic view showing the influence of particles of different diameters on the scattering property of light, wherein (1) in fig. 3 shows the haze of light of different wavelengths when the particle diameter is smaller than 1 μm, (2) in fig. 3 shows the haze of light of different wavelengths when the particle diameter is between 1 μm and 3 μm, (3) in fig. 3 shows the haze of light of different wavelengths when the particle diameter is between 3 μm and 4 μm, and (4) in fig. 3 shows the haze of light of different wavelengths when the particle diameter is between 5 μm and 7 μm. The haze may reflect the degree of scattering of light, wherein the greater the haze, the higher the degree of scattering of light. As is apparent from (1) to (4) in fig. 3, the particle diameter changes and the scattering effect of the particles on light of different wavelengths also changes. As can be seen from (1) in fig. 3, when the particle diameter is smaller than 1 μm, the particles may undergo rayleigh scattering, and the haze in the blue band is significantly larger than those in the red and green bands, i.e., the scattering degree in the blue band is significantly stronger than those in the red and green bands. As can be seen from (2) to (4) in fig. 3, when the particle diameter is greater than 1 μm, the haze of the blue light band is similar to the haze of the red light band and the green light band, i.e., the scattering degree of the particles to the blue light band is similar to the scattering degree of the red light band and the green light band. Therefore, it can be further proved that in the embodiment of the application, by adding the scattering particles with the diameter smaller than 1 μm into the substrate, the absorption of the pigment in the filter material to the light in the blue light band can be specifically increased, and the absorption to the light in the red light band and the light in the green light band can be reduced. The light transmittance of the blue light wave band can be reduced on the basis that the light transmittance of the red light wave band and the green light wave band is not affected.

FIG. 4 is a schematic diagram showing the relationship between haze and wavelength when the diameter of the scattering particles is about 0.1 μm, and as shown in FIG. 4, the haze of the blue light band can reach about 40% when the diameter of the scattering particles is about 0.1 μm, and the haze of the red light band and the green light band is only about 10%, further demonstrating that when the diameter of the scattering particles is less than 1 μm, the scattering degree of the blue light band can be significantly stronger than the scattering degree of the red light band and the green light band, and demonstrating that the feasibility of the embodiment of the present application is higher.

In a specific implementation, in the optical filter material provided by the embodiment of the application, the haze of the light rays of the blue light wave band in the optical filter material can be in a range of 30% -50%, and the haze of the light rays of the green light wave band in the optical filter material can be less than 20%; the haze of light in the red band in the filter may be less than 10%. Therefore, the scattering degree of the filter material on the blue light wave band is higher, and the scattering degree of the filter material on the red light wave band and the green light wave band is lower.

Fig. 5 is a diagram showing a comparison of the filtering effect between the filter material provided with no scattering particles and the filter material provided with scattering particles, and fig. 5 (1) is a diagram showing the filter material provided with no scattering particles, and in fig. 5 (1), the pigment 102 is dispersed in the base material 101 of the filter material. Fig. 5 (2) shows a filter material provided with scattering particles. In fig. 5 (2), pigment 102 and scattering particles 103 are dispersed in a base material 101 of the filter, and the haze of light Y1 in the blue wavelength band in the filter is 40%, the haze of light Y2 in the green wavelength band in the filter is 10%, and the haze of light Y3 in the red wavelength band in the filter is 5% as an example. In the embodiment, a pigment 102 capable of reducing the transmittance of light Y1 in the blue wavelength band and transparent scattering particles 103 having a refractive index of less than 1.5 and a diameter of less than 0.1 μm may be added to the substrate 101 having a refractive index of about 1.5, and the substrate 101, the pigment 102, and the scattering particles 103 may be mixed to form a blend system, or a filter layer having the pigment 102 or the scattering particles 103 may be formed. By adjusting the concentration of the scattering particles 103, the haze in the blue band can be 40%, the haze in the green band can be 10%, and the haze in the red band can be 5%. The filter material in (1) in fig. 5 has the same structure as the filter material in (2) in fig. 5 except that no scattering particles are provided.

As shown in fig. 5 (1), the transmittance of the light Y1 in the blue wavelength band after passing through the filter is about 2%, the transmittance of the light Y2 in the green wavelength band after passing through the filter is about 96%, and the transmittance of the light Y3 in the red wavelength band after passing through the filter is about 96%. As shown in (2) of fig. 5, the transmittance of the light Y1 in the blue wavelength band after passing through the filter is about 1.2%, the transmittance of the light Y2 in the green wavelength band after passing through the filter is about 95.8%, and the transmittance of the light Y3 in the red wavelength band after passing through the filter is about 95.8%. As can be seen from comparing (1) with (2) in fig. 5, by adding the scattering particles 103 to the filter layer, the transmittance of the blue light band can be greatly reduced, for example, the transmittance of the blue light band is reduced from 2% to 1.2%. The amplitude of the decrease of the transmittance of the red light wave band and the green light wave band is very small and is reduced to 95.8 from 96%, which further proves that the light transmittance of the blue light wave band can be reduced on the basis that the transmittance of the light of the red light wave band and the green light wave band is not affected by adding the scattering particles 103 to the substrate 101.

Based on the same technical concept, the embodiment of the application also provides a display module, which may be an organic light emitting diode display module or a micro light emitting diode display module, or may be other types of display modules, which is not limited herein. The display module in the embodiment of the application can be applied to display equipment such as mobile phones, tablet computers, notebook computers, intelligent watches and the like.

Fig. 6 is a schematic structural diagram of a display module provided in an embodiment of the present application, and fig. 7 is another schematic structural diagram of a display module provided in an embodiment of the present application, as shown in fig. 6 and fig. 7, a display module in an embodiment of the present application may include: a substrate 20, a plurality of light emitting devices located over the substrate 20, and a filter layer 10 located on a side of the light emitting devices facing away from the substrate 20. The plurality of light emitting devices in the display module may include: at least one red light emitting device 21R, at least one green light emitting device 21G, and at least one blue light emitting device 21B. The filter layer 10 includes a plurality of openings U, each corresponding to one of the blue light emitting devices 21B, the front projection of the opening U on the substrate 20 having an overlapping area with the front projection of the corresponding blue light emitting device 21B on the substrate.

In the embodiment of the present application, the substrate may be solid, so that the structure of the filter layer may be relatively stable. In a specific implementation, the filter layer may be made of the above filter material, and when the material in the above filter material is liquid or colloid, the substrate mixed with pigment and scattering particles may be coated on the light emitting device, and after curing, the filter layer may be formed on the light emitting device. When the base material in the above-mentioned filter material is solid, the base material mixed with pigment and scattering particles may be used as a filter layer, and the filter layer may be directly attached to the light emitting device.

Referring to fig. 2, the filter layer may include: the light source comprises a substrate 101, a pigment 102 and scattering particles 103, wherein the pigment 102 is positioned in the substrate 101, the pigment 102 is used for absorbing light Y1 in a blue light wave band, the scattering particles 103 are used for scattering the light Y1 in the blue light wave band, and the scattering degree of the light Y1 in the blue light wave band in a filter layer is larger than the scattering degree of the light in a red light wave band and a green light wave band in the filter layer. In a specific implementation, the scattering particles may include: silica, aluminum oxide, titanium oxide, zirconium oxide, indium tin oxide, antimony doped tin dioxide, organosiloxane, polystyrene, polyamide or polymethyl methacrylate. The diameter of the scattering particles may be less than 3 μm, for example, the diameter of the scattering particles may be less than 1 μm. The implementation of the optical filter layer may refer to the implementation of the optical filter material, and the repetition is not repeated.

In this embodiment of the application, through set up the filter layer in display module assembly, the filter layer can be on the basis that does not influence the transmissivity of the light of red light wave band and green light wave band, and the increase is to the absorptivity of the light of blue light wave band, therefore, the unnecessary light of blue light wave band in the display module assembly can be filtered to the filter layer to make display module assembly have wider colour gamut, promote display module assembly's whole display effect, and reduce display module assembly's consumption. In addition, the filter film layer is provided with an opening at the position corresponding to the blue light-emitting device, so that the blue light emitted by the blue light-emitting device can be directly emitted, and the redundant blue light wave band light rays in the red light-emitting device and the green light-emitting device are filtered, so that the normal display effect of the display module is not affected.

Alternatively, in the embodiment of the present application, the thickness of the filter layer may be in a range of 1 μm to 10 μm, so that the absorptivity of the filter layer in the blue band is high. Of course, the thickness of the filter layer may be greater than 10 μm or less than 1 μm, and may be set according to practical situations, and the thickness of the filter layer is not limited here. In addition, the absorption rate of the filter layer to the blue light band can be adjusted by adjusting the concentration of pigment and scattering particles in the filter layer.

In an embodiment of the present application, the display module may be an organic light emitting diode display module. In the organic light emitting diode display module, the light emitting device may include an organic light emitting diode, which may include an anode, a cathode, and a light emitting layer between the anode and the cathode.

As shown in fig. 6, in the organic light emitting diode display module, the light emitting efficiency and the lifetime of the blue light emitting device 21B are low, so that a corresponding structure is provided in the organic light emitting diode display module to increase the transmittance of blue light and improve the overall display effect of the organic light emitting diode display module. However, the structure also causes the transmittance of blue light in the reflected ambient light to be increased, so that the overall effect of the organic light emitting diode display module is blue when the screen is closed. In this embodiment, through setting up filter layer 10 in organic light emitting diode display module assembly, can filtering unnecessary blue light wave band's light in the organic light emitting diode display module assembly to, filter layer 10 is equipped with opening U in the position department that corresponds to blue light emitting device 21B, thereby can make the blue light that blue light emitting device 21B flew out can directly be penetrated, and unnecessary blue light wave band's light in filtering red light emitting device 21R and the green light emitting device 21G, thereby can be on the basis that does not influence the normal display of organic light emitting diode display module assembly, solve the problem of unblanking under the screen state.

With continued reference to fig. 6, the organic light emitting diode display module may further include: the filter layer 10 may be disposed on a side of the touch layer 23 facing away from the substrate 20, and the package layer 22 covering the plurality of light emitting devices, and the touch layer 23 disposed on a side of the package layer 22 facing away from the substrate 20. The encapsulation layer 22 may block moisture and oxygen from the light emitting device. By arranging the touch layer 23 inside the display module, the display module can have a touch function. The filter layer 10 is disposed on the side of the touch layer 23 facing away from the substrate 20, so that the filter layer 10 can be prevented from affecting the packaging effect of the light emitting device and preventing the touch effect of the filter layer 10.

In addition, the organic light emitting diode display module may further include: a polarizer 24, and an optical cement layer 25 between the polarizer 24 and the filter layer 10. The polarizer 24 can reduce the reflectivity of the organic light emitting diode display module and improve the display contrast of the organic light emitting diode display module.

In another embodiment of the present application, the display module may be a micro light emitting diode display module, in which a color conversion method may be used to implement color display, as shown in fig. 7, the blue light emitting device 21B may include: blue micro light emitting diode 211. The red light emitting device 21R may include: the blue micro light emitting diode 211, and a first color conversion layer 212 covering the blue micro light emitting diode 211, the first color conversion layer 212 is configured to convert light of a blue light band into light of a red light band, so that the red light emitting device 21R emits light of the red light band. The green light emitting device 21G may include: the blue micro light emitting diode 211, and a second color conversion layer 213 covering the blue micro light emitting diode 211, the second color conversion layer 213 being for converting light of a blue light band into light of a green light band, thereby causing the green light emitting device 21G to emit light of the green light band. Alternatively, the first color conversion layer 212 and the second color conversion layer 213 may be materials such as phosphor or quantum dots.

However, because the blue-violet light band component exists in the ambient light, in the state that the micro light emitting diode display module is at the screen-off state, the blue-violet light band component still can cause the photoluminescent material in each blue micro light emitting diode to be excited, so that the screen-off reflectivity of the micro light emitting diode display module is increased, and the display contrast of the display module is reduced. In addition, in the red light-emitting device and the green light-emitting device, after the blue excitation light emitted by the blue micro light-emitting diode passes through the color conversion layer, part of the blue excitation light still exists, so that part of blue light is mixed in the light emitted by the red light-emitting device and the green light-emitting device, the display color bias of the display module is caused, and the display color gamut is lower.

In this embodiment, as shown in fig. 7, by disposing the filter layer 10 in the micro light emitting diode display module, and the filter layer 10 is located on one side of the first color conversion layer 212 and the second color conversion layer 213 facing away from the substrate 20, the filter layer 10 is provided with an opening U at a position corresponding to the blue light emitting device 21B. Thereby, the blue light emitted from the blue light emitting device 21B can be directly emitted, and the excessive blue light wave band light in the red light emitting device 21R and the green light emitting device 21G can be filtered. Thus, the filter layer 10 can absorb blue light leaked at the positions of the red light emitting device 21R and the green light emitting device 21G, increase the purity of outgoing light of the red light emitting device 21R and the green light emitting device 21G, and improve the display color gamut. Therefore, the problems of blue shift in the screen-off state and color shift in the normal display process can be solved on the basis of not affecting the normal display of the micro light-emitting diode display module.

In addition, as shown in fig. 7, the micro light emitting diode display module may further include: a touch layer 23 on the side of the filter layer 10 facing away from the substrate 20, and a cover plate 26 on the side of the touch layer 23 facing away from the substrate. By providing the touch layer 23, the micro light emitting diode display module can have a touch function. By providing the cover plate 26, the internal structure of the micro led display module can be protected. In the manufacturing process, the touch layer 23 may be formed on the surface of the cover plate 26, and then, the cover plate 26 is installed on the side of the filter layer 10 facing away from the substrate 20 with the surface of the side of the cover plate 26 having the touch layer 23 facing the substrate 00, so that, in fig. 7, the touch layer 23 is disposed on the side of the filter layer 10 facing away from the substrate 20.

Based on the same technical concept, the embodiment of the present application further provides a method for manufacturing a display module, and fig. 8 is a flowchart of the method for manufacturing a display module provided in the embodiment of the present application, as shown in fig. 8, where the method for manufacturing a display module may include:

s301, providing a substrate provided with a plurality of light emitting devices; wherein the plurality of light emitting devices includes: at least one red light emitting device, at least one green light emitting device, and at least one blue light emitting device;

S302, adopting a base material mixed with pigment and scattering particles to manufacture a filter layer on a plurality of light-emitting devices; alternatively, the filter layer may be directly formed on the surface of the light emitting device, or may be formed on the surface of another film layer over the light emitting device. The pigment is used for absorbing light rays of a blue light wave band, and the scattering particles are used for scattering the light rays of the blue light wave band, so that the scattering degree of the light rays of the blue light wave band in the filter layer is greater than the scattering degree of the light rays of the red light wave band and the green light wave band in the filter layer;

and S303, removing part of the area in the filter layer to form an opening in the area corresponding to the blue light emitting device.

In this embodiment of the application, through forming the filter layer on light emitting device, the filter layer can be on the basis that does not influence the transmissivity of the light of red light wave band and green light wave band, increases the absorptivity to the light of blue light wave band, therefore, unnecessary blue light wave band in the display module assembly can be filtered to the look filter layer to make the display module assembly have wider colour gamut, promote the whole display effect of display module assembly, and reduce display module assembly's consumption. In addition, through carrying out the patterning to the filter layer, set up the opening in the position department that corresponds to blue light emitting device to can make the blue light that blue light emitting device emergent can directly go out, and unnecessary blue light wave band in filtering red light emitting device and the green light emitting device can not influence the normal display effect of display module assembly.

In some embodiments of the present application, the step S302 may include:

the filter layer is attached over the plurality of light emitting devices.

When the base material is solid, the base material mixed with pigment and scattering particles can be used as a filter layer, and the filter layer can be directly attached to the light-emitting device, so that the manufacturing process is simpler.

In other embodiments of the present application, the step S302 may include:

Alternatively, the substrate coated over the plurality of light emitting devices may be cured by photo-curing or thermal curing. The filter layer is formed on the light-emitting device by adopting a coating process and a curing process, and the manufacturing process is more compatible with the manufacturing process of other film layers in the display module, so that the manufacturing cost is saved.

In practice, the pigment and scattering particles may be homogeneously mixed within the substrate in the following manner:

Mode one: the pigment and the scattering particles may be homogeneously mixed in the substrate by physical means. The pigment and the scattering particles can be placed in the base material, and the pigment and the scattering particles are uniformly dispersed in the base material by adopting a mechanical stirring mode. In addition, physical parameters such as viscosity can be adjusted during mechanical stirring to promote uniform mixing of pigment and scattering particles in the substrate.

Mode two: the pigment and the scattering particles may be chemically mixed homogeneously in the substrate. Placing a pigment, scattering particles and a dispersing agent in a substrate; wherein the dispersing agent is used for adjusting the dispersion degree of the scattering particles in the substrate. The dispersing agent can be coated on the surface of the scattering particles, so that the scattering particles can not be aggregated together, and the dispersing agent has the properties of hydrophilicity and lipophilicity, so that one end of the dispersing agent can be connected with the scattering particles, and the other end of the dispersing agent can be connected with the base material, thereby achieving the effect of adjusting the dispersion degree of the scattering particles in the base material, and realizing that the pigment and the scattering particles are uniformly mixed in the base material. Alternatively, the dispersant may be an organofunctional group, or the dispersant may be other materials, not limited herein.

While preferred embodiments of the present application have been described, additional variations and modifications in those embodiments may occur to those skilled in the art once they learn of the basic inventive concepts. It is therefore intended that the following claims be interpreted as including the preferred embodiments and all such alterations and modifications as fall within the scope of the application.

It will be apparent to those skilled in the art that various modifications and variations can be made to the embodiments of the present application without departing from the spirit and scope of the embodiments of the present application. Thus, if such modifications and variations of the embodiments of the present application fall within the scope of the claims and the equivalents thereof, the present application is intended to encompass such modifications and variations.

Claims

A filter material, comprising: a substrate, and pigment and scattering particles dispersed within the substrate;

the pigment is used for absorbing light rays of a blue light wave band;

the scattering particles are used for scattering light rays of a blue light wave band, so that the scattering degree of the light rays of the blue light wave band in the filter material is greater than the scattering degree of the light rays of the red light wave band and the green light wave band in the filter material.
The filter material of claim 1, wherein the scattering particles comprise: silica, aluminum oxide, titanium oxide, zirconium oxide, indium tin oxide, antimony doped tin dioxide, organosiloxane, polystyrene, polyamide or polymethyl methacrylate.
The filter material of claim 1 or 2, wherein the scattering particles have a diameter of less than 3 μm.
The filter material of claim 1, wherein the haze of the blue band light in the filter material is in the range of 30% to 50%; the haze of the light rays of the green light wave band in the filter material is less than 20%; the haze of the light rays in the red light wave band in the filter material is less than 10%.
The filter material of any one of claims 1-4, further comprising: a dispersant dispersed within the substrate;

the dispersing agent is used for adjusting the dispersion degree of the scattering particles in the substrate;

the difference between the median particle diameter and the true particle diameter of the scattering particles within the substrate is less than 25%; the median particle size is a particle size value corresponding to the cumulative distribution percentage of the scattering particles in the base material reaching 50%, and the actual particle size is an average value of all the scattering particles before being placed in the base material.
The filter material of any of claims 1-5, wherein the pigment is present in a concentration of greater than 10%.
The filter material of any one of claims 1-6, wherein the substrate is a liquid, a gel, or a solid.
A display module, comprising: the light emitting device comprises a substrate, a plurality of light emitting devices and a filter layer, wherein the light emitting devices are arranged on the substrate;

the plurality of light emitting devices includes: at least one red light emitting device, at least one green light emitting device, and at least one blue light emitting device;

The filter layer comprises a plurality of openings; each opening corresponds to one blue light emitting device, and the orthographic projection of the opening on the substrate has an overlapping area with the orthographic projection of the corresponding blue light emitting device on the substrate;

the filter layer includes: a substrate, and pigment and scattering particles within the substrate; the pigment is used for absorbing light rays of a blue light wave band; the scattering particles are used for scattering light rays of a blue light wave band, so that the scattering degree of the light rays of the blue light wave band in the filter layer is larger than the scattering degree of the light rays of the red light wave band and the green light wave band in the filter layer.
The display module of claim 8, wherein the light emitting device comprises an organic light emitting diode;

the display module assembly still includes: the packaging layer covers the plurality of light emitting devices, and the touch control layer is positioned on one side of the packaging layer away from the substrate;

the filter layer is positioned on one side of the touch layer, which is away from the substrate base plate.
The display module assembly of claim 8 or 9, further comprising: and the optical adhesive layer is positioned between the polaroid and the filter layer.
The display module of claim 8, wherein the blue light emitting device comprises: blue micro light emitting diode;

the red light emitting device includes: the LED comprises a blue micro light-emitting diode and a first color conversion layer covering the blue micro light-emitting diode, wherein the first color conversion layer is used for converting light rays of a blue light wave band into light rays of a red light wave band;

the green light emitting device includes: the light emitting device comprises a blue micro light emitting diode and a second color conversion layer covering the blue micro light emitting diode, wherein the second color conversion layer is used for converting light rays of a blue light wave band into light rays of a green light wave band;

the filter layer is positioned on one side of the first color conversion layer and the second color conversion layer, which is away from the substrate.
A display module according to any one of claims 8 to 11, wherein the thickness of the filter layer is in the range 1 μm to 10 μm.
A display module according to any one of claims 8 to 12, wherein the scattering particles comprise: silica, aluminum oxide, titanium oxide, zirconium oxide, indium tin oxide, antimony doped tin dioxide, organosiloxane, polystyrene, polyamide or polymethyl methacrylate.
A display module according to any one of claims 8 to 13, wherein the scattering particles have a diameter of less than 3 μm.
A display module according to any one of claims 8 to 14, wherein the substrate is a solid.
The manufacturing method of the display module is characterized by comprising the following steps:

providing a substrate provided with a plurality of light emitting devices; wherein the plurality of light emitting devices includes: at least one red light emitting device, at least one green light emitting device, and at least one blue light emitting device;

a substrate mixed with pigment and scattering particles is adopted to manufacture a filter layer on the plurality of light-emitting devices; the pigment is used for absorbing light rays of a blue light wave band, and the scattering particles are used for scattering the light rays of the blue light wave band, so that the scattering degree of the light rays of the blue light wave band in the filter layer is greater than the scattering degree of the light rays of the red light wave band and the green light wave band in the filter layer;

and removing part of the area in the filter layer to form an opening in the area corresponding to the blue light emitting device.
The method of manufacturing of claim 16, wherein said using a substrate mixed with pigment and scattering particles to create a filter layer over said plurality of light emitting devices comprises:

Providing a filter layer formed by a substrate mixed with pigment and scattering particles;

attaching the filter layer over the plurality of light emitting devices.
The method of manufacturing of claim 16, wherein said using a substrate mixed with pigment and scattering particles to create a filter layer over said plurality of light emitting devices comprises:

mixing the pigment and the scattering particles in a liquid or colloidal state of a substrate;

coating the substrate mixed with the pigment and the scattering particles over the plurality of light emitting devices;

curing the substrate coated on the plurality of light emitting devices to obtain the filter layer.
The method of claim 18, wherein the pigment and the scattering particles are uniformly mixed within the substrate by:

disposing the pigment and the scattering particles within the substrate;

and uniformly dispersing the pigment and the scattering particles in the base material by adopting a mechanical stirring mode.
The method of claim 18, wherein the pigment and the scattering particles are uniformly mixed within the substrate by:

Placing the pigment, the scattering particles and the dispersing agent in the substrate; wherein the dispersing agent is used for adjusting the dispersion degree of the scattering particles in the base material.