TW202113405A - A backlight module and a display device - Google Patents

Abstract

A backlight module comprises a frame, a diaphragm unit disposed on the frame, and a light unit located between the frame and the diaphragm unit. The frame includes a bottom wall and a plurality of support columns on the bottom wall and spaced apart from each other, wherein the height of the support column is gradually increased from the center of the bottom wall toward the periphery. The diaphragm unit is disposed on the frame and is supported by the support column. The diaphragm unit forms a downwardly concave curved surface along with the height of the support columns, and can transfer the light emitted from the light emitting unit into a planar light source. According to the height of the support columns being gradually increased from the center of the bottom wall to the periphery, the diaphragm unit forms a downwardly concave curved surface, thereby greatly reducing the warpage phenomenon of the diaphragm unit and improving the uniformity of the chromatic aberration. This invention further provides a display device including the backlight module.

Description

Backlight module and display device

The invention relates to an optical device, in particular to a backlight module and a display device.

In order to make the LCD panel of the LCD display its picture clearly, in addition to the ambient light from the outside, a set of backlight modules including light-emitting elements are generally installed on the back of the LCD panel to provide the backlight, especially Large-area liquid crystal panels require the use of direct-lit backlight modules that include many light-emitting elements to provide sufficient backlight sources.

However, although the aforementioned direct-lit backlight module can provide the backlight source required by a large-area liquid crystal panel, the area of the optical film used in the direct-lit backlight module corresponds to the large size of the liquid crystal panel, and the optical film It is stacked up and down, and only the peripheral edges are placed flat on the frame. In addition, due to the processing of the material and the material characteristics of the material itself, the optical films are easily affected by heat or gravity. The warpage phenomenon is caused. As the degree of warpage is higher, the color of the light emitted will obviously deviate from the normal white light, which will affect the function of the uniformity of chromatic aberration of the optical films, and cannot meet the display requirements of high-saturated color images.

Therefore, the object of the present invention is to provide a backlight module that can reduce the warpage of the optical film.

The backlight module of the present invention includes a frame, a film unit arranged on the frame, and a light-emitting unit located between the frame and the film unit. The frame includes a bottom wall and a plurality of supporting columns arranged on the bottom wall at intervals, wherein the height of the supporting columns is gradually increased from the center of the bottom wall to the peripheral edge. The diaphragm unit is arranged on the frame and supported by the supporting pillars. The diaphragm unit forms a downwardly concave curved surface with the height of the supporting pillars, and can emit light from the light-emitting unit Converted into a flat light source.

Another technical means of the present invention is that the bottom wall has a plurality of positioning grooves, and the supporting columns are respectively inserted and positioned in the positioning grooves.

Another technical means of the present invention is that the supporting columns are arranged on the bottom wall in a matrix.

Another technical means of the present invention is that the top surface of the support column is coated with an adhesive, and the membrane unit is fixed on the support column via the adhesive.

Another technical means of the present invention is that the frame further includes a surrounding wall extending upward from the periphery of the bottom wall, and the periphery of the diaphragm unit is positioned on the surrounding wall.

Another technical means of the present invention is that the backlight module further includes a reflection unit disposed on the bottom wall of the frame, the reflection unit has a plurality of first perforations arranged at intervals, and the support pillars pass through the The first perforation supports the diaphragm unit.

Another technical means of the present invention is that the light-emitting unit includes a circuit board arranged between the bottom wall of the frame and the reflecting unit, and a plurality of light-emitting elements arranged on the circuit board at intervals, and the reflecting unit also has A plurality of second perforations are arranged at intervals, and the light emitting elements respectively pass through the second perforations.

Another technical means of the present invention is that the circuit board of the light-emitting unit has a plurality of through holes arranged at intervals, and the through holes correspond to the first through holes of the reflecting unit for the frame. The supporting pillars are respectively arranged correspondingly.

Another object of the present invention is to provide a display device including the aforementioned backlight module and a display panel arranged on the backlight module.

The effect of the present invention is that, as the height of the support column is gradually higher from the center of the bottom wall to the peripheral edge, the diaphragm unit will form a downwardly concave curved surface with the height of the support column. The warpage of the diaphragm unit is reduced, so that the light can be prevented from being affected by the warping phenomenon when the light is emitted, and the color of the light is close to the normal white light, thereby improving the uniformity of chromatic aberration to meet the display requirements of high-saturated color images.

The features and technical content of the related patent applications of the present invention will be clearly presented in the following detailed description of the preferred embodiments with reference to the drawings. Before detailed description, it should be noted that similar components are denoted by the same numbers.

1 is a preferred embodiment of the backlight module of the present invention, which includes a frame 2, a light-emitting unit 3 arranged on the frame 2, a reflective unit 4 arranged on the light-emitting unit 3, and a The diaphragm unit 5 on the reflecting unit 4. The diaphragm unit 5 is used to convert the light emitted by the light-emitting unit 3 into a planar light source, where the diaphragm unit 5 may include a brightness enhancement film, an upper fin, a lower fin, a diffuser, a color conversion film, etc. All kinds of optical films have to be selected according to actual needs and increase or decrease in quantity.

1 and 2, the frame 2 includes a bottom wall 21, a surrounding wall 22 extending upward from the periphery of the bottom wall 21, and a plurality of supporting columns 23 spaced apart and arranged in a matrix on the bottom wall 21. Wherein, as shown in FIG. 2, the bottom wall 21 has a plurality of positioning grooves 211, and the supporting posts 23 are respectively inserted and positioned in the positioning grooves 211 to be coupled to the bottom wall 21. Of course, the bottom end of the supporting column 23 may be coated with glue to be fixed in the positioning groove 211, or it may be pressed tightly in the positioning groove 211 in a tight-fitting manner. It should be particularly noted that in this preferred embodiment, whether along the X direction or the Y direction, the height of the support column 23 is gradually increased from the center of the bottom wall 21 to the direction of the surrounding wall 22 .

Referring to FIG. 3, the light-emitting unit 3 includes a circuit board 31 arranged on the bottom wall 21 of the frame 2 and a plurality of light-emitting elements 32 arranged on the circuit board 31 at intervals. Wherein, the circuit board 31 has a plurality of through holes 311 arranged at intervals for the supporting pillars 23 of the frame 2 to be respectively penetrated.

The reflecting unit 4 has a plurality of first perforations 41 arranged at intervals and a plurality of second perforations 42 arranged at intervals. The first perforations 41 correspond to the through holes 311 on the circuit board 31. The supporting pillars 23 of the frame 2 respectively pass through the through holes 311 and the first through holes 41, and the light emitting elements 32 of the light emitting unit 3 respectively pass through the first holes of the reflecting unit 4 Two perforations 42 make the circuit board 31 and the reflection unit 4 stable and adhere to the bottom wall 21 of the frame 2.

3, when the preferred embodiment is assembled, the light-emitting unit 3 is first arranged on the bottom wall 21 of the frame 2, and the supporting column 23 passes through the corresponding hole on the circuit board 31孔311. Then, the reflecting unit 4 is further arranged so that the supporting column 23 passes through the corresponding first through hole 41 on the reflecting unit 4, and the light-emitting element 32 of the light-emitting unit 3 passes through the upper part of the reflecting unit 4. Corresponding second perforation 42.

1 and 3, when the light-emitting unit 3 and the reflecting unit 4 have been firmly installed on the bottom wall 21 of the frame 2, the diaphragm unit 5 is installed on the frame 2 and is supported by the supporting column 23 support the top. In this embodiment, the periphery of the diaphragm unit 5 is positioned on the surrounding wall 22, and the rest is supported by the supporting pillar 23. It should be noted that the top surface of the supporting column 23 is coated with an adhesive, and the membrane unit 5 is fixed and bonded to the supporting column 23 through the adhesive. Of course, the top edge of the surrounding wall 22 of the frame 2 can also be coated with an adhesive, so that the periphery of the membrane unit 5 is also adhered to the surrounding wall 22 to improve the bonding stability. Since the height of the support column 23 is gradually higher from the center of the bottom wall 21 to the peripheral edge, when the diaphragm unit 5 is set up, the diaphragm unit 5 will follow the support from the peripheral edge to the center. The height of the pillar 23 gradually decreases to form a downwardly concave curved surface, as shown in FIG. 1.

It should be further explained that the support column 23 is of a plug-in design, which can be easily adjusted in height, and can be replaced with a support column 23 of different heights according to the requirements of different sizes or degrees of depression. The supporting pillars 23 are arranged in a matrix, which can provide sufficient supporting force to each part of the diaphragm unit 5, so that the diaphragm unit 5 is in a stable and gradually recessed shape, without localized problems. Lack of the support of the support pillar 23 and too sag, which affects the uniformity of light emission.

In addition, the arrangement of the reflecting unit 4 can reflect the light of the light-emitting element 32 to enter the diaphragm unit 5, avoiding the leakage of energy of the light-emitting element 32, and can improve the brightness of the light. The reflection unit 4 is designed with a first perforation 41 for the support pillar 23 to pass through, which can limit the movement of the reflection unit 4 and prevent the reflection unit 4 from shifting and shielding the backlight module of the present invention during the movement process. The situation of the light-emitting element 32 is described.

Because of the direct-lit backlight module, there must be sufficient light mixing space between the light-emitting element 32 and the diaphragm unit 5. Therefore, the diaphragm unit 5 needs to be supported by the supporting column 23 to make the diaphragm unit 5 There is a certain distance between the unit 5 and the light emitting element 32. However, the diaphragm unit 5 is prone to partial upward warping (waving) due to thermal expansion or gravity, which affects the uniformity of the diaphragm unit 5 and causes aggravation of chromatic aberration. In the present invention, by designing the height of the support column 23 to be low in the center and high in the outside, the central position of the diaphragm unit 5 is slightly recessed downward, and the diaphragm unit 5 is offset by gravity. The tendency of expansion or other factors to bulge upwards can effectively avoid the problem of local warpage of the diaphragm unit 5.

Refer to FIG. 4, which shows the variation curve of the color difference value with the degree of warpage of the diaphragm unit 5, where the color difference value uses the chromaticity diagram as the color reference, and the measured color is related to the color of the light emitted by the backlight module. Numerical values, the chromaticity diagram shows all the chromaticities that are visible to ordinary people, and the color gamut of various areas is called the color gamut of human vision. The color gamut of all visible chromaticities on the CIE drawing is the shape of a horseshoe shown in color. The curved boundary of the color gamut is called the "spectral locus" and corresponds to monochromatic light. The wavelength is marked with nanometers, and the white color is located in the center of the color gamut. It should be noted that, FIG. 4 compares the color difference values measured in the area of the light-emitting surface of the backlight module that deviates most from the white position. It can be seen from FIG. 4 that when the warpage value of the diaphragm unit 5 is lower, the corresponding color difference value is lower. That is to say, if the warpage value of the diaphragm unit 5 can be reduced, it can avoid the effect of warpage during the light emission and make the light color approach the normal white light, thereby improving the uniformity of chromatic aberration and making the overall light color more It is uniform to meet the display requirements of high-saturated color images.

Referring to FIG. 5, when a display panel 6 is arranged above the aforementioned backlight module, it is a display device including the backlight module.

In summary, the backlight module and the display device of the present invention adjust the height of the support column 23 of the frame 2 to make it appear in an arrangement gradually lowering from the outside to the center, and the diaphragm unit 5 is arranged at When the frame 2 is on, it can naturally present a state where the center is slightly recessed downward, and gravity is used to offset the phenomenon that the diaphragm unit 5 may locally bulge upward, effectively avoiding the problem of local warpage of the diaphragm unit 5, It can avoid the influence of warping phenomenon when the light is emitted, and the color of the light can be close to the normal white light, thereby improving the overall chromatic aberration uniformity and optimizing the optical taste.

However, the above are only preferred embodiments of the present invention, and should not be used to limit the scope of implementation of the present invention, that is, simple equivalent changes and modifications made in accordance with the scope of the patent application of the present invention and the description of the invention, All are still within the scope of the invention patent.

2: frame 21: bottom wall 211: positioning slot 22: Surround the wall 23: Support column 3: Light-emitting unit 31: circuit board 311: Piercing Hole 32: luminous parts 4: reflection unit 41: The first perforation 42: second piercing 5: Diaphragm unit 6: Display panel

FIG. 1 is a schematic cross-sectional side view, which is a preferred embodiment of the backlight module of the present invention; Figure 2 is a partial perspective view to assist in explaining the structure of a frame in Figure 1; Figure 3 is a partial enlarged view of the enlarged state of the frame in Figure 1 Figure 4 is a graph illustrating the variation of chromatic aberration with the degree of warpage of a diaphragm unit; and FIG. 5 is a schematic cross-sectional side view, which is a preferred embodiment of the display device of the present invention.

2: frame

21: bottom wall

22: Surround the wall

23: Support column

3: Light-emitting unit

4: reflection unit

5: Diaphragm unit

Claims (9)

A backlight module, including: A frame, including a bottom wall, and a plurality of supporting columns arranged on the bottom wall at intervals, wherein the height of the supporting columns is gradually increased from the center of the bottom wall to the peripheral edge; A diaphragm unit arranged on the frame and supported by the support pillars, the diaphragm unit will form a downwardly concave curved surface with the height of the support pillars; and A light-emitting unit is located between the frame and the diaphragm unit, and the diaphragm unit can convert the light emitted by the light-emitting unit into a planar light source. According to the backlight module described in item 1 of the scope of patent application, the bottom wall has a plurality of positioning grooves, and the supporting pillars are respectively inserted and positioned in the positioning grooves. According to the backlight module described in item 1 of the scope of patent application, the supporting pillars are arranged in a matrix on the bottom wall. According to the backlight module described in claim 1, wherein the top surface of the supporting column is coated with an adhesive, and the film unit is fixed on the supporting column via the adhesive. According to the backlight module of claim 1, wherein the frame further includes a surrounding wall extending upward from the periphery of the bottom wall, and the periphery of the diaphragm unit is positioned on the surrounding wall. The backlight module according to any one of items 1 to 5 of the scope of patent application further includes a reflection unit disposed on the bottom wall of the frame, the reflection unit having a plurality of first perforations arranged at intervals, and the supporting column The diaphragm unit is propped up through the first perforations respectively. According to the backlight module described in item 6 of the scope of patent application, the light-emitting unit includes a circuit board arranged between the bottom wall of the frame and the reflecting unit, and a plurality of light-emitting elements arranged on the circuit board at intervals The reflecting unit also has a plurality of second perforations arranged at intervals, and the light-emitting elements respectively pass through the second perforations. The backlight module according to item 7 of the scope of patent application, wherein the circuit board of the light-emitting unit has a plurality of through holes arranged at intervals, and the through holes correspond to the first through holes of the reflecting unit. , For the supporting pillars of the frame to be penetrated respectively. A display device includes a backlight module as described in any one of items 1 to 8 of the scope of patent application, and a display panel arranged on the backlight module.

Images