TW201514587A - Backlight module device - Google Patents

Abstract

A backlight module device comprises: an optical diffusion module, a light mixing chamber, a plurality of light guide elements, and a plurality of light sources. The light mixing chamber has at least a light mixing chamber bottom surface, and at least a light mixing chamber side. The optical diffusion module, the light mixing chamber bottom surface and the light mixing chamber side form a light mixing space. The light guide element has at least a light incident plane. The light guide element is disposed with a light beam deflection structure at other external surfaces or inside the light guide element except the light incident plane. The light beam deflection structure could deflect the light beam to conduct the inside of the light guide element to allow the light beam exiting the external surface of the light guide element. The plurality of light guide elements respectively retain proper distances with respect to the optical diffusion module and the light mixing chamber bottom surface and is disposed in the light mixing space. At least a light source is disposed near the light mixing chamber side and at the light incident plane near the light guide element.

Description

Backlight module device

The present invention relates to a backlight module device, and more particularly to a backlight module device that requires uniform illumination, weight reduction, and thinness.

Conventionally, a backlight module device mainly uses a cold cathode fluorescent lamp (CCFL) or a light-emitting diode (LED) as its light source. Since the light-emitting diode LED has energy saving and environmental protection characteristics compared with the cold cathode tube CCFL, in recent years, the light-emitting diode LED has gradually replaced the cold cathode tube CCFL as a main light-emitting element. However, the light-emitting diode LED belongs to a point light source with high directivity. To achieve the required uniform illumination, it must be diffused or mixed by the backlight module device; currently, there are mainly: Edge Lighting backlight module. Group and Direct Lighting backlight modules.

The side-illuminated backlight module is a plurality of LED light sources, which form a light bar, form a line light source, and then diffuse or mix light through the light guide plate, and then project to the optical diffusion module. Because the area of the light guide plate is large, the thickness needs to be minimized to reduce the weight and cost of the light guide plate. However, in a thinner light guide plate, in order to achieve uniform diffusion or light mixing, the LED light sources can only be arranged in a relatively dense manner, so the number and cost of LEDs cannot be reduced.

The direct type backlight module is formed by an array of multiple LED light sources. The surface light source is directly projected onto the optical diffusion module. Although the direct-lit backlight module has no light guide plate arrangement, to achieve uniform diffusion or light mixing, one of the arrays of LED light sources is arranged in a relatively dense manner, so the number and cost of LEDs cannot be reduce. Another way is to increase the distance between the optical diffusion module and the bottom surface of the light mixing cavity, so that the light has a sufficient distance to mix light, which makes the direct-lit backlight module difficult to be thinned.

An object of the present invention is to provide a backlight module device capable of reducing the number of light sources, reducing the weight of the light guiding device, and improving the problem of thinning.

The invention provides a backlight module device, comprising: an optical diffusion module. a light mixing cavity; having at least one bottom surface of the light mixing cavity and at least one side of the light mixing cavity. The optical diffusion module, the bottom surface of the light mixing cavity, and the side of the light mixing cavity form a light mixing space. A plurality of light guiding elements are included, the light guiding elements having at least one light incident surface. The light guiding element is provided with a light redirecting structure on the other outer surface or inside the light guiding element in addition to the light incident surface. The light redirecting structure can steer the light conducted inside the light guiding element to pass the light out of the outer surface of the light guiding element. The plurality of light guiding elements are respectively disposed at an appropriate distance from the bottom surface of the optical diffusion module and the light mixing cavity, and are disposed in the light mixing space. The method includes at least one light source disposed adjacent to a side of the light mixing cavity and adjacent to a light incident surface of the light guiding element.

According to an embodiment of the invention, the distance between the plurality of light guiding elements and the optical diffusing module may be different. The plurality of light guiding elements may be different from the bottom surface of the light mixing chamber. The distance between the light guiding element and the adjacent light guiding elements may not be the same.

According to an embodiment of the invention, the shape of the light guiding element may be three-dimensional Strips, plates or rods in space. The surface of the light guiding element may be a flat surface or a curved surface in space. The cross section of the light guiding element may be a quadrilateral, a polygon, a circle, an ellipse, a triangle or a combination of the above.

According to an embodiment of the invention, the light redirecting structure is disposed on the outer surface of the light guiding element or inside the light guiding element, and may be a plurality of convex or concave mesh points, spheres, prisms (Prism) , Cone, cylinder, lateral serration, or the composite geometry described above.

According to an embodiment of the invention, the light redirecting structure on the light guiding element is disposed near the outer surface or the inner region of the light guiding element at a certain side position to form a main light emission, and another reverse direction. To shine.

According to an embodiment of the present invention, the primary or secondary illumination may be projected onto the bottom surface of the light mixing cavity and reflected by the bottom surface of the light mixing cavity, and the projection width projected onto the optical diffusion module is enlarged and formed. Returning to the reflection phenomenon on the side surface of the light guiding element, and traversing the surface of the light guiding element, hitting the light turning structure, resulting in a composite diffusion or reflection phenomenon.

Compared with the prior art, the present invention increases the distance between the light guiding elements due to the expansion of the projection width and the composite diffusion and reflection effects. Therefore, the weight of the light guiding element can be reduced, the number of light sources can be reduced, or the distance between the optical diffusion module and the bottom surface of the light mixing cavity can be shortened, and the backlight module device of the present invention can be made thinner.

According to an embodiment of the invention, the light on the light guiding element is turned to the surface of the structure, and a turning or reflecting device may be added; the turning or reflecting device may be a coating, a matte surface or a bite; or alternatively, another A component that can be assembled.

11‧‧‧Backlight module device

12‧‧‧Optical diffusion module

13‧‧‧Hybrid cavity

13a‧‧‧Bottom of the mixing chamber

13b‧‧‧mixing cavity side

14‧‧‧Light guiding elements

14a‧‧‧light incident surface

14b‧‧‧ spacing

14c‧‧‧ spacing

14d‧‧‧ spacing

15‧‧‧Light source

16‧‧‧Hybrid space

17‧‧‧Light turn structure

18a‧‧‧Main light

18a1‧‧‧The main type of primary light

18a2‧‧‧Main light type II

18a3‧‧‧The third type of main light

W18a‧‧‧Main illuminating projection width

W18a1‧‧‧ main illumination first type projection width

W18a2‧‧‧Main illumination second type projection width

18b‧‧‧second light

18b1‧‧‧second light first type

18b2‧‧‧second light to shine the second type

18b3‧‧‧ secondary light type III

W18b‧‧‧ secondary illuminating projection width

W18b1‧‧‧ secondary illumination of the first type of projection width

W18b2‧‧‧ secondary illumination second type projection width

19‧‧‧Steering or reflectors

Figure 1 is an exploded perspective view of an embodiment of the present invention.

Figure 2 is a schematic cross-sectional view showing an embodiment of the present invention.

Fig. 3 is a schematic view showing the outer shape and cross section of a light guiding member according to an embodiment of the present invention.

Figure 4 is a schematic view of a light redirecting structure in accordance with an embodiment of the present invention.

Fig. 5 is a cross-sectional view showing the light-emitting direction of a light guiding element according to an embodiment of the present invention.

Figure 6 is a schematic cross-sectional view of a light path according to an embodiment of the present invention.

Figure 7 is a cross-sectional view showing another light path of an embodiment of the present invention.

Figure 8 is a cross-sectional view showing another light path of an embodiment of the present invention.

Figure 9 is a cross-sectional view showing another light path of an embodiment of the present invention.

Figure 10 is a cross-sectional view showing another light path of an embodiment of the present invention.

Figure 11 is a cross-sectional view showing another light path of an embodiment of the present invention.

Figure 12 is a schematic cross-sectional view of a steering or reflecting device in accordance with an embodiment of the present invention.

FIG. 1 is an exploded perspective view of an embodiment of the present invention. The backlight module device 11 of the embodiment includes: an optical diffusion module 12 having light diffusion properties, which may be a single or multiple optical elements such as a diffusion plate, a diffusion film, a brightness enhancement film, and a light transmission layer. Compounded. There is a light mixing cavity 13 having at least one light mixing cavity bottom surface 13a and at least one light mixing cavity side surface 13b; the light mixing cavity 13 may be integrally formed or combined. The surface of the bottom surface 13a of the light mixing chamber has light reflecting or diffusing properties; and may also be coated or attached on the surface thereof. A light reflecting or diffusing property is achieved. The surface of the side surface 13b of the light mixing cavity may be either light-reflective or diffusive. The backlight module device 11 of the embodiment further has a plurality of light guiding elements 14. The light guiding element 14 has at least one light incident surface 14a; at least one light source 15 is disposed adjacent to the side surface 13b of the light mixing chamber and adjacent to the light incident surface 14a of the light guiding element 14 for injecting light into the light guiding element. 14 internal.

2 is a schematic cross-sectional view showing an embodiment of the present invention. The optical diffusion module 12 of the embodiment, the bottom surface 13a of the light mixing cavity, and the side surface 13b of the light mixing cavity form a light mixing space 16 so that light can be mixed in the light mixing space 16 and finally optically. The diffusion module 12 emits light uniformly. The plurality of light guiding elements 14 are respectively disposed at an appropriate distance from the optical diffusion module 12 and the bottom surface 13a of the light mixing chamber, and are disposed in the light mixing space 16. The light guiding element 14 and the optical diffusion module 12 form a spacing 14b. The light guiding element 14 and the bottom surface 13a of the light mixing chamber form another spacing 14c. The light guiding element 14 forms another distance 14d between the adjacent light guiding elements 14. The plurality of light guiding elements 14 may be different from the distance 14b of the optical diffusing module 12, respectively. The plurality of light guiding elements 14 may be different from the pitch 14c of the bottom surface 13a of the light mixing chamber. The distance between the plurality of light guiding elements 14 and the adjacent light guiding elements 14 may be different from each other.

As shown in FIG. 3, it is a schematic diagram of the outer shape and cross section of the light guiding element 14 according to an embodiment of the present invention. The outer shape of the light guiding element 14 of the present embodiment may be a strip shape, a plate shape or a rod shape in a three-dimensional space. The surface of the light guiding element 14 may be a flat surface or a curved surface in space. The cross section of the light guiding element 14 may be quadrilateral, polygonal, circular, elliptical, triangular or a combination of the above. The light guiding elements 14 may have different shapes, surfaces, cross sections, and the like.

As shown in FIG. 4, it is a schematic diagram of a light redirecting structure according to an embodiment of the present invention. this In addition to the light incident surface 14a, the light guiding element 14 of the embodiment is provided with a light redirecting structure 17 on the other outer surface or inside the light guiding element 14. The light redirecting structure 17 may be a plurality of convex or concave mesh dots, spheres, prisms, cones, cylinders, lateral serrations, or composite structures as described above. Formed. Therefore, the light redirecting structure 17 can steer the light conducted inside the light guiding element 14 to pass the light out of the surface of the light guiding element 14.

As shown in FIG. 5, it is a schematic cross-sectional view of a light guiding direction of a light guiding element 14 according to an embodiment of the present invention. When the light redirecting structure 17 on the light guiding element 14 of the present embodiment is disposed on the outer surface or the inner region near the +Y side position, the main light emitting 18a formed is in the -Y direction, and the secondary light emitting 18b is toward +Y direction. The general light steering structure 17 is designed to minimize the luminous flux of the secondary illumination 18b, typically in percentages between about 0% and 30% of the total luminous flux. The main light emission 18a and the light emission angle of the secondary light emission 18b may be full-circumference light rays that are connected to 360 degrees.

FIG. 6 is a schematic cross-sectional view of a light path according to an embodiment of the present invention. The light redirecting structure 17 is disposed adjacent to the +Y side position of the light guiding element 14. Thus, the secondary illumination 18b is in the +Y direction, and its light 18b can be directly projected onto the optical diffusion module 12 to form a projection width of W18b. The main light 18a is in the -Y direction, and the first type of light 18a1 is projected onto the bottom surface 13a of the light mixing chamber, and is reflected by the bottom surface 13a of the light mixing chamber to reach the optical diffusion module 12 to form a projection width of W18a1. Since the traveling path of the light 18a1 is a distance of reflection and round-trip, the path length is about 1.5 to 3 times that of the traveling path of the light 18b, so W18a1 is also about 1.5 to 3 times that of W18b.

FIG. 7 is a schematic cross-sectional view showing another light path according to an embodiment of the present invention. The main illuminating 18a second type of light 18a2 is that its illuminating angle gradually approaches the positive-Y square By the reflection of the bottom surface 13a of the light mixing chamber, the light 18a2 is returned to the light guiding element 14 on the side surface in the +X or -X direction, so that a reflection phenomenon of another set of larger projection widths W18a2 can be formed.

FIG. 8 is a schematic cross-sectional view showing another light path according to an embodiment of the present invention. The main light 18a of the third type of light 18a3 is that the light-emitting angle is very close to the positive-Y direction, and the light 18a3 will return and pass through the surface of the light-guiding element 14 in the -Y direction through the reflection of the light-mixing cavity bottom surface 13a, and then hit. The light turns to structure 17, creating more complex diffuse or reflective phenomena that contribute to the elimination of dark bands of light and uniform mixing.

Therefore, in comparison with the prior art, the present invention increases the distance 14d between the light guiding elements 14 due to the expansion of the projection width (W18a1, W18a2) and the composite diffusion or reflection effect (18a3). Therefore, the number and weight of the light guiding elements 14 can be reduced, and the number of the light sources 15 can also be reduced. Alternatively, the distance between the optical diffusion module 12 and the bottom surface 13a of the light mixing chamber can be shortened, so that the backlight module 11 can be assembled. Thin.

FIG. 9 is a schematic cross-sectional view showing another light path according to an embodiment of the present invention. The light redirecting structure 17 is disposed near the +Y side of the light guiding element 14, and the main light emitting 18a is in the -Y direction, and when the +Y direction has no secondary light emitting 18b, the light path is 18a1, 18a2, 18a3, etc. It is also possible to obtain an expansion of the projection width (W18a1, W18a2) and a composite diffusion or reflection effect (18a3).

FIG. 10 is a schematic cross-sectional view showing another light path according to an embodiment of the present invention. The light redirecting structure 17 is disposed adjacent to the -Y side of the light guiding element 14. Thus, the main light 18a is in the +Y direction, and the light 18a can be directly projected onto the optical diffusion module 12 to form the projection width of the W18a. The secondary illumination 18b is in the -Y direction, and its three types of light 18b1, 18b2, 18b3, respectively, can obtain W18b1, W18b2 projection width, and 18b3 composite diffusion or reflection phenomenon. Therefore, in this embodiment, the weight of the light guiding member 14 can be reduced, the number of the light guiding members 14 and the light source 15 can be reduced, or the effect of thinning can be achieved.

FIG. 11 is a schematic cross-sectional view showing another light path according to an embodiment of the present invention. The light redirecting structure 17 is disposed adjacent to the -Y side of the light guiding element 14. When the main light 18a is in the +Y direction and there is no secondary light 18b in the -Y direction, the effect of reducing the weight of the light guiding element 14 and reducing the number of the light sources 15 can still be obtained.

As shown in FIG. 12, it is a schematic cross-sectional view of a steering or reflecting device 19 according to an embodiment of the present invention. The light on the light guiding element 14 is turned to the surface of the structure 17, and a turning or reflecting means 19 can be additionally provided; the turning or reflecting means 19 can be a coating, a matte or a bite; or another component that can be assembled . In this way, the luminous flux of the secondary luminescence can be made to approach zero.

11‧‧‧Backlight module device

12‧‧‧Optical diffusion module

13‧‧‧Hybrid cavity

13a‧‧‧Bottom of the mixing chamber

13b‧‧‧mixing cavity side

14‧‧‧Light guiding elements

14a‧‧‧light incident surface

15‧‧‧Light source

Claims (10)

A backlight module device includes: an optical diffusion module. a light mixing cavity; having at least one bottom surface of the light mixing cavity and at least one side of the light mixing cavity. The optical diffusion module forms a light mixing space with the bottom surface of the light mixing cavity and the side of the light mixing cavity. a plurality of light guiding elements; the light guiding element having at least one light incident surface. The light guiding element is provided with a light redirecting structure on the other outer surface or inside the light guiding element in addition to the light incident surface. The light redirecting structure can steer the light conducted inside the light guiding element to pass the light out of the outer surface of the light guiding element. The plurality of light guiding elements are respectively disposed at an appropriate distance from the bottom surfaces of the optical diffusion module and the light mixing cavity, and are disposed in the light mixing space. At least one light source is disposed adjacent to a side of the light mixing cavity and adjacent to a light incident surface of the light guiding element. According to the backlight module device of claim 1, the distance between the plurality of light guiding elements and the optical diffusing module may be different. The plurality of light guiding elements may be different from the bottom surface of the light mixing chamber. The distance between the plurality of light guiding elements and the adjacent light guiding elements may not be the same. According to the backlight module device of claim 1, the outer shape of the light guiding element may be a strip shape, a plate shape or a rod shape in a three-dimensional space. The surface of the light guiding element, It can be a plane or a surface in space. The cross section of the light guiding element may be a quadrilateral, a polygon, a circle, an ellipse, a triangle or a combination of the above. The light guiding elements may have different shapes, surfaces, cross sections, and the like. According to the backlight module device of claim 1, the light redirecting structure is disposed on the outer surface or inside of the light guiding element, and may be a plurality of convex or concave mesh points, a sphere (Sphere), a prism (Prism), Cone (Cone), cylinder (Cylinder), lateral serration, or the composite geometry described above. The backlight module device of claim 1, wherein the light guiding structure of the light guiding element is disposed on an outer surface or an inner region near the (+Y) side of the optical diffusion module, and the main light emitting direction is to be mixed. The (-Y) direction of the bottom surface of the cavity, the secondary illumination direction is the (+Y) direction of the optical diffusion module. The backlight module device of claim 5, wherein the secondary light emission toward the optical diffusion module (+Y) direction may be no light. The backlight module device of claim 1, wherein the light guiding structure of the light guiding element is disposed on an outer surface or an inner region near a bottom surface (-Y) side of the light mixing chamber, and the main light emitting direction is optical diffusion. The (+Y) direction of the module, the secondary illumination direction is the (-Y) direction to the bottom of the mixing cavity. The backlight module device of claim 7, wherein the secondary light emission toward the bottom surface (-Y) of the light mixing chamber may be no light. According to the backlight module device of claim 1, the illumination angle of the primary illumination and the secondary illumination may be a full-circumference illumination that is connected to 360 degrees. According to the backlight module device of claim 1, the non-light emitting surface of the light guiding element can be additionally provided with a turning or reflecting device. The steering or reflecting device can be a coating, matte or bite; or another component that can be assembled.