TWM552672U - LED module and its backlight device - Google Patents

Description

Light-emitting diode module and backlight device thereof

The present invention is a technology for designing an optical component, and particularly relates to a light-emitting diode module and a backlight thereof which can reduce the bright band problem of a direct-lit backlight device.

With the advancement of technology, the traditional cathode ray tube TV has been eliminated by the market because of its large size. Instead, it is a thin TV, such as a liquid crystal display. Since the liquid crystal display does not actively emit light, it is necessary to have a light-emitting device as a light source required for display, which is generally referred to as a backlight device. In the design of the backlight device, there are roughly two types, one is a side light type, and the other is a direct type. Taking the light-emitting diode as a light source as an example, although the edge-lit backlight device has the advantages of being thin and low in cost, it has uneven brightness, for example, the main display area in the middle is dark, and the edge is rather bright. In the direct type backlight device, the light emitting diode is disposed under the liquid crystal panel to form a side light source. Although it is necessary to use a larger number of light-emitting diodes than the edge-lit backlights, since the direct-type backlights have better light utilization efficiency than the edge-lit backlights, they are currently widely used, for example, in large Size on the LCD display.

Please refer to FIG. 1 , which is a cross-sectional view of a conventional direct type backlight module. The direct type backlight module 1 mainly has a casing 10 . The casing 10 has a slope 11 around the casing 10 and has a reflective structure thereon. The housing 10 has an accommodating space 100 therein, and has a plurality of LED modules 12, each of which has a light-emitting diode 120 and an optical component 121, which is a lens. . Since the direct type backlight module 1 needs to install a considerable number of light emitting diodes 120, sufficient backlight can be generated, but this inevitably increases the cost. In order to solve this problem, the light divergence angle which can be enlarged by the optical element 121 (lens) above the light-emitting diode 120 is, for example, about ±150 degrees, and the number of the light-emitting diodes 120 can be reduced. Although the manner shown in FIG. 1 can enlarge the light-emitting range of the direct-type backlight module 1, the light-emitting diodes 120 are all oriented toward a high-power design, and after the diffusion of the optical element 121, the optical path A in FIG. The energy of the upper and lower edges of the backlight module 1 penetrating the reflective paper 13 is too strong, resulting in a distinct bright band. Therefore, how to eliminate the bright group problem caused by the optical path A without affecting the uniformity of the backlight is a problem to be solved in the future.

Although in the conventional technique, or in the inclined surface 11 of Fig. 1, an adsorbing material is provided for adsorbing light or perforating, allowing light to pass, to reduce the problem of the surrounding bright band, it also reduces the efficiency of use of light. In summary, there is a need for a light-emitting diode module and a backlight thereof to solve the problems caused by conventional techniques.

The present invention provides a light-emitting diode module and a backlight thereof, which utilizes optical elements disposed between a reflective slope and a light-emitting diode to expand a light beam exceeding a certain angle (θ) through optical characteristics thereof. To reduce the bright band at the edge of the LED module.

In one embodiment, the present disclosure provides a light emitting diode module including a light emitting diode element and a first optical element. The light emitting diode element has an optical axis, and the light emitting diode element has a first light emitting range centered on the optical axis. The first optical component is disposed on one side of the light emitting diode element for receiving a light beam in the first light emitting range that exceeds a specific angle (θ) around the optical axis, and expands the light beam into a first Two illumination range.

In one embodiment, the present disclosure provides a backlight device including a housing and at least one LED module. The housing has an accommodating space, and the accommodating space has at least one inclined surface around the accommodating space. The at least one light emitting diode module is disposed in the accommodating space adjacent to the at least one inclined surface, and each of the light emitting diode modules further has a light emitting diode element and a first optical component. The light emitting diode element has an optical axis, and the light emitting diode element has a first light emitting range centered on the optical axis. The first optical component is disposed on one side of the light emitting diode element for receiving a light beam in the first light emitting range that exceeds a specific angle (θ) around the optical axis, and expands the light beam into a first Two illumination range.

In an embodiment, the LED component further includes a light emitting diode and a second optical component. The light emitting diode is configured to generate an initial light emitting range centered on the optical axis. The second optical component is overlaid on the LED to receive the initial illumination range and expand into the first illumination range.

In an embodiment, the first optical element has a distance from the optical axis that is less than or equal to 20 mm. The first optical element has a height h, where h is less than or equal to the product of tan(90-θ) and the distance.

In an embodiment, the first optical component has a light receiving surface and a light emitting surface, and the light receiving surface receives the light beam exceeding a certain angle, and the light emitting surface is expanded by the first optical component to the second light emitting range. Leaving the first optical element. Wherein, the light incident surface is a plane or a concave surface. The illuminating surface is a convex surface, wherein the convex surface further has a plurality of microstructured surfaces arranged in an array. In an embodiment, the microstructured surface is a convex surface.

Please refer to FIG. 2A to FIG. 2D , which are a plan view, a partial enlargement and a BB cross-sectional view of the direct type backlight device of the present invention. In this embodiment, the backlight device 2 has a housing 20 and at least one LED module 21 . The housing 20 has an accommodating space 200 therein, and the periphery of the housing 20 is formed by connecting at least one inclined surface 22. The slope 22 can be a reflective surface, but is not limited thereto. Each of the LED modules 21 further includes a light emitting diode element 210 and a first optical element 211. The light emitting diode element 210 has an optical axis 90. In this embodiment, the LED component 210 further has a light emitting diode 212 and a second optical component 213. The light field generated by the light-emitting diode 212 has an initial light-emitting range 900 centered on the optical axis 90, which is the original light-emitting range of the light-emitting diode 212. In an embodiment, the initial illumination range is between approximately ±110 and ±120 degrees, but is not limited thereto. The second optical component 213 is disposed over the LED 212. In this embodiment, the LED 212 is disposed in a chamber inside the second optical component 213 for receiving the initial The illumination range 900 is expanded and expanded into the first illumination range 901. In an embodiment, the second optical component 213 is a lens. The positional relationship between the light-emitting diode 212 and the second optical element 213 can be determined according to actual needs, and is also well known to those skilled in the art, and thus is not limited by the contents shown in the drawings. The first illumination range 901 can be between ±70 and ±80 degrees. In an embodiment, the first illumination range 901 is between approximately ±75 degrees.

The first optical component 211 is disposed between the LED component 210 and the corresponding slope 22 for receiving a beam of the first illumination range 901 that exceeds the optical axis 90 by a specific angle (θ). And expanding the beam into a second illumination range 902. The particular angle (θ) is between about 70 and 85 degrees, and in one embodiment, the particular angle is 78 degrees. After the light beam larger than the specific angle (θ) is reflected by the inclined surface 22, a bright band is generated at the edge of the light-emitting surface of the backlight device 2. This embodiment is provided through the arrangement of the first optical element 211 to eliminate or slow down the problem of the bright band.

It can be seen in FIG. 2B that in the first illumination range 901, the optical path is greater than the specific angle, for example, a light beam of 78 degrees passes through the first optical element 211, and after entering the first illumination element 211, further The first optical element 211 expands to form a second illumination range 902. In the present creation, since the optical path exceeding the specific angle (θ) is not directly projected onto the inclined surface 22 to cause reflection, it is first optically modulated by the first optical element 211 to be expanded, and then projected onto the inclined surface 22. Therefore, the energy of each of the light beams projected to the inclined surface 22 is weaker than the energy directly projected to the inclined surface 22 without passing through the first optical element 211, and therefore, even if reflected from the inclined surface 22, since the light intensity has been lowered, It is possible to reduce the problem of bright band caused by the direct-type backlight device having a secondary lens reflecting light from the inclined surface 22. It should be noted that the first light-emitting element 211 can be disposed at one of the four circumferences 91-94 of the casing 20 as needed, or any combination. In the embodiment, the first optical element 211 is disposed at The circumference of the casing is 91~94.

As shown in FIG. 2B and FIG. 2D, the figure is a schematic view of the first optical component of the present invention. In the embodiment, the first optical component 211 has a light receiving surface 2110 and a light emitting surface 2111, and the light receiving surface 2110 receives the excess. A light beam of a specific angle (θ) is expanded into the second light-emitting range 902 via the first optical element 211, and then exits the first optical element 211 from the light-emitting surface 2111. In an embodiment, the light incident surface 2110 is a flat surface, and the light exit surface 2111 is a convex surface structure. In another embodiment, the light incident surface 2110 can be a concave structure. Please refer to FIG. 3, which is a perspective view of another embodiment of the first optical component of the present invention. In this embodiment, the light-emitting surface of the first optical element 211 is a convex surface 214, and the surface of the convex surface 214 further has a plurality of microstructured surfaces 215 arranged in an array, such as a sub-convex surface, to form a plurality of sub-surfaces. The convex first optical element 211, through such a design, each of the sub-convex surfaces can expand the corresponding light beam, thereby increasing the light-expanding effect of the light beam entering the first optical element 211.

Next, the positional relationship between the first optical element of the present creation and the light-emitting diode will be described. As shown in FIG. 2D, the central axis 91 of the first optical element 211 has a distance d from the optical axis 90. The height h of the lens of the first optical element 211 is determined by the specific angle θ and the distance d. In an embodiment, the height h is determined by the specific angle θ being less than or equal to 78 degrees and the distance d. In an embodiment of the present creation, the height h is less than or equal to the product of tan(90-θ) and the distance d, where θ is the specific angle value, and the distance d is less than or equal to 20 mm. In one embodiment, the first optical element 211 is a thin piece having a thickness t between 3 and 5 mm. The first optical element 211 obtained by the above-described parameter design is placed in a direct backlight device having a secondary lens (second optical element 213) to apply the display, and the large-angle secondary optical lens can be effectively eliminated. The resulting problem of bright clusters around.

Please refer to FIG. 4 , which is a schematic diagram of the comparison of the masses caused by the LED module of the present invention and the LED module without using the present invention under the same backlight device. The light-emitting diode module of the present invention is disposed in the A side region of FIG. 4, and the conventional light-emitting diode module shown in FIG. 1 is disposed in the B-side region. According to the effect test of the light-emitting brightness, it can be found that when the light-emitting diode module 21 in the A-side region is projected onto the inclined surface 22, the bright-band region generated at the boundary is compared with the conventional light-emitting diode module 12 in the B-side region. The resulting bright band area is gentle and has a small range; in addition, in the A side, it is also apparent that there is no position where the brightness is particularly concentrated, and in the area where the B side is close to the inclined surface 22, there are obvious bright band areas C and D. . Therefore, by using the optical element disposed between the reflective slope and the light-emitting diode by the present invention, the light beam exceeding a certain angle (θ) is expanded by the optical characteristic thereof, and the edge of the light-emitting diode module can be reduced. Bright band effect.

However, the specific embodiments described above are only used to illustrate the features and functions of the present invention, and are not intended to limit the scope of implementation of the present invention, without departing from the spirit and technology of the present invention. The equivalent changes and modifications made by the present disclosure are still covered by the scope of the following patent application.

1‧‧‧Direct type backlight module
10‧‧‧shell
11‧‧‧Bevel
100‧‧‧ accommodating space
12‧‧‧Lighting diode module
120‧‧‧Lighting diode
121‧‧‧Optical components
2‧‧‧Direct type backlight
20‧‧‧shell
200‧‧‧ accommodating space
21‧‧‧Lighting diode module
210‧‧‧Lighting diode components
211‧‧‧First optical component
2110‧‧‧Into the glossy surface
2111‧‧‧Glossy surface
212‧‧‧Lighting diode
213‧‧‧Second optical component
214‧‧ ‧ convex
215‧‧‧Microstructured surface
22‧‧‧Slope
90‧‧‧ optical axis
91~94‧‧‧around the shell
900‧‧‧Initial illumination range
901‧‧‧First illumination range
902‧‧‧Second illumination range θ‧‧‧specific angle
A, B‧‧‧ side areas
C, D‧‧‧ bright belt area

FIG. 1 is a schematic view of a conventional direct type backlight device. 2A is a top plan view of the direct type backlight device of the present invention. 2B is a top plan view showing the optical path of the light-emitting diode module in the partial region of the direct-type backlight device of the present invention. 2C is a cross-sectional view showing the CC of the direct type backlight device of the present invention shown in FIG. 2A. 2D is a schematic view showing the positional relationship between the light emitting diode module and the first optical component in the direct type backlight device of the present invention. 3 is a perspective view of another embodiment of the first optical component of the present invention. FIG. 4 is a schematic diagram showing the comparison of the masses caused by the LED module of the present invention and the LED module without the use of the present invention under the same backlight device.

20‧‧‧shell

21‧‧‧Lighting diode module

210‧‧‧Lighting diode components

211‧‧‧First optical component

2110‧‧‧Into the glossy surface

2111‧‧‧Glossy surface

212‧‧‧Lighting diode

213‧‧‧Second optical component

22‧‧‧Slope

Θ‧‧‧specific angle

Claims (16)

A light emitting diode module comprising: a light emitting diode element having an optical axis, the light emitting diode element having a first light emitting range centered on the optical axis; and a first optical component One side of the light emitting diode element receives a light beam in the first light emitting range that exceeds a specific angle centered on the optical axis, and expands the light beam into a second light emitting range. The illuminating diode module of claim 1, wherein the illuminating diode component further comprises: a illuminating diode for generating an initial illuminating range centered on the optical axis; A second optical component is overlying the LED to receive the initial illumination range and expand it into the first illumination range. The light-emitting diode module of claim 1, wherein the first optical element has a distance from the optical axis, the distance being less than or equal to 20 mm. The illuminating diode module of claim 3, wherein the first optical element has a height h, wherein h is less than or equal to the product of tan(90-θ) and the distance, wherein the θ is the specific Angle value. The light-emitting diode module of claim 1, wherein the first optical component has a light-receiving surface and a light-emitting surface, and the light-receiving surface receives the light beam exceeding a certain angle through the first optical component. After extending to the second illumination range, the light exiting surface exits the first optical element. The light-emitting diode module of claim 5, wherein the light-incident surface is a plane or a concave surface. The light-emitting diode module of claim 5, wherein the light-emitting surface is a convex surface. The illuminating diode module of claim 7, wherein the convex surface further comprises a plurality of microstructured surfaces arranged in an array. A backlight device includes: a housing having an accommodating space, wherein the accommodating space has at least one inclined surface; and at least one illuminating diode module disposed in the accommodating space, and the at least one Each of the light emitting diode modules further has: a light emitting diode element having an optical axis, the light emitting diode element having a first light emitting range centered on the optical axis; and a first An optical component disposed between the light emitting diode component and the corresponding inclined surface for receiving a light beam in the first light emitting range that exceeds a specific angle centered on the optical axis, and expanding the light beam into a second light emitting range. The backlight device of claim 9, wherein the LED component further comprises: a light emitting diode for generating an initial light emitting range centered on the optical axis; and a second optical And an element covering the LED body for receiving the initial illumination range and expanding the first illumination range. The backlight device of claim 9, wherein the first optical element has a distance from the optical axis, the distance being less than or equal to 20 mm. The backlight device of claim 11, wherein the first optical element has a height h, wherein h is less than or equal to a product of tan(90-θ) and the distance, wherein the θ is the specific angle value. The backlight device of claim 9, wherein the first optical element has a light receiving surface and a light emitting surface, and the light receiving surface receives the light beam exceeding a specific angle, and expands into the first optical element The second illuminating range is followed by the illuminating surface away from the first optical element. The backlight device of claim 13, wherein the light incident surface is a plane or a concave surface. The backlight device of claim 13, wherein the light emitting surface is a convex surface. The backlight device of claim 15, wherein the convex surface further comprises a plurality of microstructured surfaces arranged in an array.