Light source assembly used for backlight module, backlight module and liquid crystal displayer

[0028] Example 1

[0029] This embodiment provides a light source assembly for a backlight module, such as figure 2 As shown, the light source assembly includes a substrate 1 and an LED chip 2 encapsulated on the substrate 1. The LED chip 2 is provided with an optical conversion part 3, and the optical conversion part 3 is used to emit light from the LED chip 2 Monochromatic light is converted to white light. Specifically, the LED chip 2 may be a blue LED chip or an ultraviolet LED chip. The optical conversion part 3 includes a glass box body 3a and a phosphor or phosphor powder 3b encapsulated in the glass box body 3a.

[0030] Wherein, the phosphor or phosphor 3b can be a quantum dot material phosphor or phosphor, for example, it can be CdS, ZnS, PbS, CdSe, ZnSe, PbSe, CdTe, CdTeSe, InP, AgInS, CuInS, CuInSe One or more. The phosphor or phosphor may also be a conventional phosphor or phosphor, for example, it may be nitride, oxynitride, silicate, sulfide, fluoride material, etc.

[0031] Further, as figure 2 As shown, the optical conversion part 3 is also provided with a filter film set 4, and the filter film set 4 is used to narrow the wavelengths of red, green and blue light in the white light emitted by the optical conversion part 3. range.

[0032] Specifically, such as image 3 As shown, the filter film set 4 includes a plurality of first type films 4a and a plurality of second type films 4b. In the direction away from the optical conversion part 3, starting from the first type film 4a, the first type The thin film 4a and the second type thin film 4b are alternately laminated.

[0033] Wherein, the first type film 4a is made of a material with a refractive index of 1.38 to 2.0, and the second type film 4b is made of a material with a refractive index of 1.7 to 2.6.

[0034] Wherein, in the multilayer first-type film 4a, the material of each first-type film 4a may be individually selected from MgF 2 , SiO 2 , Al 2 O 3 , HfO 2 , MgO, ZnO and Y 2 O 3 In the multilayer second-type film 4b, the material of each second-type film 4b can be individually selected from TiO 2 , Y 2 O 3 , HfO 2 , ZnO, CeO 2 Any one of ZnSe and ZnSe.

[0035] Wherein, the total number of layers of the first type film 4a and the second type film 4b can be set in the range of 20-100 layers.

[0036] Among them, in the multilayer first-type film 4a, the thickness of each first-type film 4a can be set to be unequal, and the thickness of each first-type film 4a is selected in the range of 12.5 to 125 nm, and the multilayer second-type film In 4b, the thickness of each second type film 4b can be set to be unequal, and the thickness of each second type film 4b is selected to be in the range of 12.5 to 125 nm.

[0037] Wherein, the multilayer first-type film 4a and the multilayer second-type film 4b may be sequentially formed on the glass box body 3a of the optical conversion part 3 through a sputtering process.

[0038] With the light source assembly provided in the above embodiment, after the white light emitted from the optical conversion part 3 passes through the filter film set 4, the wavelength range corresponding to the red light, the green light and the blue light in the white light can be narrowed. When the light source assembly is applied to the backlight module of a liquid crystal display, the color purity of each pixel can be improved without changing the bandpass wavelength range of each color resist in the color filter substrate, thereby increasing the color gamut.

[0039] In a more preferred solution, for the multilayer first type film 4a and the multilayer second type film 4b, if the refractive index of the second type film 4b located in the nth layer is set to be greater than that of the n-1th layer The refractive index of the first type film 4a, where n=2, 4, 6, 8,..., for example, the refractive index of the second type film 4b located in the second layer is set to be greater than that of the first type film located in the first layer The refractive index of the film 4a, the refractive index of the second type film 4b located in the fourth layer is set to be greater than the refractive index of the first type film 4a located in the third layer, and the refraction of the second type film 4b located in the sixth layer The rate is set to be greater than the refractive index of the first type film 4a located in the fifth layer, and so on. If the filter film set 4 is arranged in this way, the filter film set 4 has a better effect on narrowing the wavelength range corresponding to the red light, the green light and the blue light in the white light. Further, if the filter effect and the production cost are considered at the same time, when the total number of layers of the first type film 4a and the second type film 4b is set in the range of 50 to 70 layers, a higher cost performance can be obtained.

[0040] As a specific example, when the material of the first type of film 4a is selected to use Y 2 O 3 , The material of the second type of film 4b uses TiO 2 , The total number of layers of the first type film 4a and the second type film 4b is 60 layers, and the penetration pattern of the prepared filter film set 4 is as follows Figure 4 As shown in the figure, ML represents the penetration map of the filter film group 4, BL1 represents the spectrum of the white light generated by the backlight before passing through the filter film group 4, and BL2 represents the white light generated by the backlight passing through the filter film Spectrum after group 4. Such as Figure 4 In the filter film set 4, the bandpass wavelength range corresponding to blue light is 420~470nm, the bandpass wavelength range corresponding to green light is 515~560nm, and the bandpass wavelength range corresponding to red light is 615~680nm. The sheet set 4 mainly filters out the light in the 480-510nm and 570-610nm wavelength bands. Since the band-pass wavelength range of the filter film group 4 corresponding to blue, green and red light is narrower than the wavelength range of the blue, green and red light in the backlight source, the passage of the filter film group 4 can be narrowed. The wavelength range corresponding to red, green and blue light in the white light. From Figure 4 It can also be seen that compared to BL1, BL2 has a narrower wavelength range for blue, green and red light, especially the long-wavelength part of blue light, the short- and long-wavelength part of green light, and the red light. The band band part.

[0041] Example 2

[0042] This embodiment provides an edge-type backlight module, such as Figure 5 As shown, the backlight module includes a back plate 10 and a reflective sheet 20, a light guide plate 30 and an optical film set 40 which are sequentially arranged on the back plate 10. The backlight module also includes a light source assembly 50 which is arranged on the guide plate. Between the side of the light plate 30 and the side wall of the back plate 10. Among them, the light source assembly 50 adopts the light source assembly provided in the first embodiment. Refer to Figure 5 And combine figure 2 The light emitted by the LED chip 2 passes through the optical conversion part 3 and the filter film group 4 in sequence, and then enters the light guide plate 30, and then is emitted from the optical film group 40 above the light guide plate 30 and provided to the liquid crystal panel.

[0043] This embodiment also provides a direct type backlight module, such as Image 6 As shown, the backlight module includes a back plate 60 and a diffuser 70 and an optical film set 80 arranged on the back plate 60. The backlight module also includes a light source assembly 90, which is arranged on the back plate 60 and the diffuser 70 In between, the light source assembly 90 is also provided with a lens 91. Among them, the light source assembly 90 adopts the light source assembly provided in Embodiment 1. Refer to Image 6 And combine figure 2 , The light emitted by the LED chip 2 passes through the optical conversion part 3 and the filter film group 4 in sequence, and then exits from the lens 91, then passes through the diffuser 70 and the optical film group 80 in sequence, and is emitted from the optical film group 80 and provided to the liquid crystal panel.

[0044] This embodiment also provides a liquid crystal display device, such as Figure 7 As shown, the liquid crystal display device includes a liquid crystal panel 100 and a backlight module 200. The liquid crystal panel 100 is arranged opposite to the backlight module 200. The backlight module 200 provides a display light source to the liquid crystal panel 100 to make The liquid crystal panel 100 displays images. Wherein, the liquid crystal panel 100 includes an array substrate 101 and a filter substrate 102 arranged oppositely, and also includes a liquid crystal layer 103 located between the array substrate 101 and the filter substrate 102. Among them, the backlight module 200 adopts the edge-type backlight module or the direct-type backlight module provided in this embodiment.

[0045] In summary, the light source assembly and the backlight module and the liquid crystal display including the light source assembly provided by the embodiments of the present invention are provided with a filter film set, and the monochromatic light generated by the LED chip is obtained through the optical conversion part After the white light, the white light passes through the filter film set. The filter film set can narrow the wavelength range of the red, green and blue light in the generated white light, without changing the bands of the color resists in the color filter substrate. In the case of the pass wavelength range, the color purity of each pixel can be improved, thereby increasing the color gamut