Patent ID: 12210183

In the drawings:100, backlight module;101, central area;102, peripheral area;103, edge area;110, light guide plate;110a, first surface;110b, second surface;110c, light incident surface;120, light source;130, light absorbing and reflecting film layer;131, magnesium layer;132, amorphous silicon layer;133, silicon dioxide layer;134, light absorbing and reflecting structure;135, gap;140, first reflective sheet;150, second reflective sheet;151, hollow portion;160, first driving structure;180, backplate;200, display device;210, display panel.

DETAILED DESCRIPTION OF EMBODIMENTS

It should be understood that the terms used herein, the specific structures and function details disclosed herein are intended for the mere purposes of describing specific embodiments and are representative. However, this application may be implemented in many alternative forms and should not be construed as being limited to the embodiments set forth herein.

As used herein, terms “first”, “second”, or the like are merely used for illustrative purposes, and shall not be construed as indicating relative importance or implicitly indicating the number of technical features specified. Thus, unless otherwise specified, the features defined by “first” and “second” may explicitly or implicitly include one or more of such features. Terms “multiple”, “a plurality of”, and the like mean two or more. In addition, terms “up”, “down”, “left”, “right”, “vertical”, and “horizontal”, or the like are used to indicate orientational or relative positional relationships based on those illustrated in the drawings. They are merely intended for simplifying the description of the present disclosure, rather than indicating or implying that the device or element referred to must have a particular orientation or be constructed and operate in a particular orientation. Therefore, these in terms are not to be construed as restricting the present disclosure. For those of ordinary skill in the art, the specific meanings of the above terms as used in the present application can be understood depending on specific contexts.

Hereinafter this application will be described in further detail with reference to the accompanying drawings and some optional embodiments.

Embodiment 1

FIG.1shows a schematic diagram of a backlight module according to a first embodiment of the present application. Referring toFIG.1, the present application discloses a backlight module. The backlight module100includes a light guide plate110, a light source120, a light absorbing and reflecting film layer130, and a first reflective sheet140. The light guide plate110is used to provide a surface light source120for the display panel, and has a first surface110a, a second surface110b, and a light incident surface110c. The first surface110ais a light emitting surface. The light incident surface110cconnects the first surface110aand the second surface110b. The light source120is disposed on the light incident surface110cof the light guide plate110for providing the light guide plate110with a linear light source120. The light absorbing and reflecting film layer130is disposed on the second surface110bof the light guide plate110for absorbing light and reflecting blue light. The first reflective sheet140is disposed on a side of the light absorbing and reflecting film layer130facing away from the light guide plate110.

The light absorbing and reflecting film layer130is a film layer that can absorb light and then reflect blue light. It has spectral selectivity and can absorb light of other colors almost uniformly and reflect blue light.

In this application, in an edge-type backlight module100, the second surface110bof the light guide plate110is provided with a light absorbing and reflecting film layer130, which absorbs light of some wavelengths and then reflects blue light, thereby increasing the proportion of blue light in the display panel to compensate for the yellowing problem of the panel display. In this solution, since the light absorbing and reflecting film layer130is disposed under the light guide plate110, it will not affect the transmittance of the display panel, and may also reduce the loss of light as much as possible when otherwise passing through more film layers. More importantly, it may absorb excess light and reflect blue light to enhance the display effect of the display panel, so as to overcome the problem of yellowing of the display panel without affecting the transmittance.

It may be appreciated that the backlight module100in this embodiment may be an edge-type backlight module100. The linear light source120of the light source120is converted into a surface light source120by the light guide plate110, and the first reflective sheet140disposed on the second surface110bof the light guide plate110mainly reflects the light leaked from the light guide plate110. In particular, the backlight module100may further include structures such as a backplate, a prism sheet, and a diffusion sheet. The backplate is disposed on the side of the first reflective sheet140facing away from the light guide plate110. The prism sheet is disposed on the first surface110aof the light guide plate110, and the diffusion sheet is disposed above the prism sheet.

Refer toFIG.2, there is shown a schematic diagram illustrating a first light absorbing and reflecting film layer according to the present application. The light absorbing and reflecting film layer130adopts a multi-film layer stacked structure. The light absorbing and reflecting film layer130includes a magnesium layer131, an amorphous silicon layer132, and a silicon dioxide layer133. The magnesium layer131is disposed on the silicon dioxide layer133. The silicon dioxide layer133is disposed on the amorphous silicon layer132. The side of the magnesium layer131facing away from the silicon dioxide layer133is adjacent to the light guide plate110. The side of the amorphous silicon layer132facing away from the silicon dioxide layer133is adjacent to the first reflective sheet140.

In this embodiment, the light absorbing and reflecting film layer130adopts a structure composed of magnesium, amorphous silicon (a-si), and silicon dioxide, and it may be configured as a whole-layer structure or as multiple light absorbing and reflecting structures134, with each light absorbing and reflecting structure134is a stacked structure using the above three materials stacked together. That is, by changing the area of the light absorbing and reflecting film layer130or changing the quantity and density of the light absorbing and reflecting structures134, the amount of reflected blue light can be adjusted to achieve the required reflection of blue light.

The light absorbing and reflecting film layer130may not only absorb light of some wavelengths, but also produce by adjustments the light that meets the preset requirements, such as blue light, red light, green light, etc. depending on selection. In particular, by controlling the thickness of the amorphous silicon layer132, the tuned absorption and resonance can be achieved. In different thickness combinations of the amorphous silicon layer132and the silicon dioxide layer133, reflection of different colors may be achieved, such as blue light, red light, green light, etc.

In the present application, the thickness of each film layer of the light absorbing and reflecting film layer130is in particular as follows: the thickness of the amorphous silicon layer132is 25 nm-40 nm, the thickness of the silicon dioxide layer133is 185 nm-200 nm, and the thickness of the magnesium layer131is 160 nm. The thickness ranges each include endpoint values, and the thickness of the magnesium layer131may be assumed within +10 nm. In this solution, the light absorbing and reflecting film layer130may absorb light of other colors and reflect blue light. The yellowing problem of the display panel may be solved by enhancing blue light or filtering out yellow light. In the exemplary technology, a yellow light filtering structure is disposed on the first surface110aof the light guide plate110, that is, on the side of the light-emitting surface of the light guide plate110. Although it can overcome the yellowing problem caused by too much yellow light and insufficient blue light on the one hand, the yellow light filtering structure would also absorb part of the light, resulting in more light loss, thereby causing the problem of greater light loss. In contrast, in the present application, by disposing the light absorbing and reflecting film layer130on the second surface110bof the light guide plate110, light does not need to pass through the light absorbing and reflecting film layer130.

Referring toFIG.3, there is shown a schematic diagram of a second light absorbing and reflecting film layer according to the present application. In another implementation, the magnesium layer131in the light absorbing and reflecting film layer130may also be removed. In particular, the light absorbing and reflecting film layer130includes an amorphous silicon layer132and a silicon dioxide layer133. The silicon dioxide layer133is disposed on the amorphous silicon layer132. The side of the silicon dioxide layer133facing away from the amorphous silicon layer132is adjacent to the light guide plate110. The side of the amorphous silicon layer132facing away from the silicon dioxide layer133is adjacent to the first reflective sheet140. The thickness of the amorphous silicon layer132lies in the range of 10 nm-30 nm, and the thickness of the silicon dioxide layer133lies in the range of 140 nm-160 nm.

After the magnesium layer131is removed, the light absorbing and reflecting film layer130also has the same function as the light absorbing and reflecting film layer130formed by the above-mentioned three layers of materials, except that there are differences in their thicknesses and reflection efficiencies. It can also improve the yellowing problem of the display panel to a certain extent, improve the display effect of the panel to meet customer needs, improve the performance and quality of the display panel, and improve user experience and satisfaction.

In this embodiment, the intensity of the emitted blue light can be adjusted by changing the area of the light absorbing and reflecting film layer130.

In one embodiment, the light emitting surface of the backlight module100is divided into a central area101and a peripheral area102. The peripheral area102is disposed to surround the central area101. The central area101corresponds to the central display area of the display panel, and the peripheral area102corresponds to the peripheral display area of the display panel. In order to solve the problem of unevenness of yellowing between the central display area and the peripheral display area of the display panel, in this embodiment, the area of the light absorbing and reflecting film layer in the central area101may be set differently than the area of the light absorbing and reflecting film layer in the peripheral area102. For example, the area of the light absorbing and reflecting film layer130in the peripheral area102may be relatively larger, so that more blue light can be reflected.

In addition to using the method of different areas, the configuration of the multiple film layers of the light absorbing and reflecting film layer130may also be different in different areas. For example, the thicknesses of the silicon dioxide layer133and the amorphous silicon layer132in the light absorbing and reflecting film layer130of the central area101may be thinner. For another example, the light absorbing and reflecting film layer130in the central area101may only use two film layers, that is, the silicon dioxide layer133and the amorphous silicon layer132, while the light absorbing and reflecting film layer130in the peripheral area102may use three film layers, that is, the amorphous silicon layer132, the silicon dioxide layer133, and the magnesium layer131.

In another embodiment, the light absorbing and reflecting film layer130may be divided into a plurality of individual light absorbing and reflecting structures134, where each light absorbing and reflecting structure134at least includes the amorphous silicon layer132and the silicon dioxide layer133. In one case, the three-layer film structure including the magnesium layer131, the amorphous silicon layer132, and the silicon dioxide layer133may be selected. In other cases, the two-layer film structure including the amorphous silicon layer132and the silicon dioxide layer133may be selected.

In this solution, the intensity of the reflected blue light may be controlled by controlling the density or number of the light absorbing and reflecting structures134. For example, the density of the light absorbing and reflecting structures134in the peripheral area102may be higher, the distance between each other may be smaller, and the number may be larger, while the density of the light absorbing and reflecting structures134in the central area101may be smaller. For the central area101, a plurality of light absorbing and reflecting structures134may be arranged evenly, while for the peripheral area102, the density of a plurality of light absorbing and reflecting structures134can be gradually increased along the direction extending from the central area101to the peripheral area102, so as to overcome the yellowing phenomenon of the peripheral area102.

Apart from adopting the solution based on quantity and density, the thicknesses of the film layers of each light absorbing and reflecting structure134may also be made different. In particular, the thickness of each layer of the light absorbing and reflecting film layer130in the central area101may be set to be relatively thinner, while the thickness of each film layer of the light absorbing and reflecting film layer130may gradually increase in the direction extending toward the edges.

The light emitting surface of the backlight module100may be slightly larger than the display area of the display panel. The area of the backlight module100beyond the display area, that is, the area corresponding to the non-display area of the display panel is the edge area103. A whole layer of light absorbing and reflecting film layer130may be formed in the edge area103, and multiple light absorbing and reflecting structures134may be used in the central area101and the peripheral area102to form an array distribution.

It may be appreciated that the above ways of changing the area, number, density and thickness of each film layer of the light absorbing and reflecting structure(s)134may be used in combination or alone, the purpose of which is to overcome the problem of uneven yellowing in different areas of the display panel and the occurrence of transitions at the junction of different areas of the display panel. In the field, parameters such as the number, density, thickness, and area of the light absorbing and reflecting structure(s)134may be reasonably set based on actual conditions, so as to address the problem of yellowing of the display panel.

Embodiment 2

FIG.4is a schematic diagram illustrating a backlight module according to a second embodiment of the present application. Referring toFIG.4, as a second embodiment of the present application, a backlight module100is disclosed. The backlight module100includes a light guide plate110, a light source120, a light absorbing and reflecting film layer130, a first reflective sheet140, a second reflective sheet150, and a backplate180.

The second reflective sheet150is disposed between the light guide plate110and the light absorbing and reflecting film layer130. The light absorbing and reflecting film layer130includes a plurality of light absorbing and reflecting structures134arranged in an array. Each light absorbing and reflecting structure134at least includes an amorphous silicon layer132and a silicon dioxide layer133. Each light absorbing and reflecting structure134is used to absorb light and reflect blue light. The second reflective sheet150includes a plurality of hollow portions151. The plurality of light absorbing and reflecting structures134are disposed in one-to-one correspondence with the plurality of hollow portions151. The first reflective sheet140is disposed on the backplate180.

The first reflective sheet140and the second reflective sheet150may be made of the same material, but the difference is that the second reflective sheet150defines a plurality of hollow portions151, which are disposed corresponding to the light absorbing and reflecting structures134, respectively.

Compared with the previous embodiment, this embodiment includes two layers of reflective sheets. The main consideration is that the light absorbing and reflecting film layer130will absorb part of the light, resulting in a slight decrease in the brightness of the backlight, although for the first embodiment the power consumption of the backlight module100may be increased to solve this problem. However, in order to further consider the problem of low power consumption in this embodiment, two layers of reflective sheets are used to solve this problem. The second reflective sheet150is directly attached to the second surface110bof the light guide plate110, so that most of the light emitted from the second surface110bof the light guide plate110is reflected by the second reflective sheet150to enhance the brightness of the backlight module100. The remaining part of the light would be absorbed by the light absorbing and reflecting film layer130which then reflects blue light, which is in turn emitted from the first surface110aof the light guide plate110.

It may be understood that the first reflective sheet140and the second reflective sheet150are both opaque and capable of reflecting light, and the hollow portion151of the second reflective sheet150is able to transmit light, and is may be provided with a transparent material or completely hollowed out without any material.

In one embodiment, the light absorbing and reflecting structures134may be respectively disposed in the hollow portions151; that is, the second reflective sheet150and the light absorbing and reflecting film layer130may be combined into one to form a composite film layer.

In particular, the backlight module100may include a central area101and a peripheral area102. The peripheral area102is arranged around the central area101. The density of the plurality of light absorbing and reflecting structures134arranged in the central area101may be smaller than the density of the plurality of light absorbing and reflecting structures134arranged in the peripheral area102.

In this embodiment, the position of each hollow portion151of the second reflective sheet150may be arranged according to the actual distribution of the light absorbing and reflecting structures134. The shape of the hollow portion151may be designed according to the shape of the light absorbing and reflecting structure134, for example, its projection on the first reflective sheet140may be a circle, a square, or the like. In particular, array arrangements such as circular array or linear array, etc. may be possible.

Embodiment 3

FIG.5is a schematic diagram of a backlight module according to a third embodiment of the present application. As shown inFIG.5, the backlight module100includes a light guide plate110, a light source120, a light absorbing and reflecting film layer130, a first reflective sheet140, a second reflective sheet150, and a first driving structure160.

The second reflective sheet150is disposed between the light guide plate110and the light absorbing and reflecting film layer130. The light absorbing and reflecting film layer130includes a plurality of light absorbing and reflecting structures134arranged in an array. Each light absorbing and reflecting structure134at least includes an amorphous silicon layer132and a silicon dioxide layer133. The light absorbing and reflecting structure134is used to absorb light and reflect blue light. The second reflective sheet150includes a plurality of hollow portions151, and the plurality of light absorbing and reflecting structures134are disposed in one-to-one correspondence with the plurality of hollow portions151. The first driving structure160is used to drive the light absorbing and reflecting film layer130to move relative to the second reflective sheet150so that the facing area A between each light absorbing and reflecting structure134and the respective hollow portion151changes. When the facing area A between each light absorbing and reflecting structure134and the respective hollow portion151is reduced, the intensity of blue light reflected by the light absorbing and reflecting structure134becomes smaller.

This embodiment differs from the previous embodiment in that the previous embodiment can only determine the intensity of the reflected blue light at the beginning of design. In this embodiment, however, real-time adjustment of blue light is achieved by providing a driving structure to change the exposed area of each light absorbing and reflecting structure134from the respective hollow portion151. That is, on the basis of the second embodiment, the light absorbing and reflecting film layer130and the second reflective sheet150are designed as a two-layer structure and are movable relative to each other. Through the control of the first driving structure160, the light absorbing and reflecting film layer130is moved, so that each hollow portion151and the respective light absorbing and reflecting structure134are no longer directly facing each other, but partially overlap, and the overlapping area between the hollow portion151and the light absorbing and reflecting structure134can be adjusted through the control of the first driving structure160. As mentioned above, the area of the non-hollow portion151of the second reflective sheet150is opaque. Therefore, the area of each light absorbing and reflecting structure134exposed at the position of the respective hollow portion151is adjusted in real time thereby adjusting the intensity of the reflected blue light in real time according to different degrees of yellowing.

This solution mainly uses a driving mechanism to control the area of eacg light absorbing and reflecting structure exposed at the position of the respective hollow portion151of the second reflective sheet150to achieve a controllable effect, thereby improving the panel display effect. Without losing the panel transmittance and increasing the backlight power consumption, this can to a certain extent improve the yellowing display phenomenon that may occur on panels, improve the display effect of the panel to meet customer needs, improve the performance and quality of the display, and improve user experience and satisfaction.

Referring toFIG.6, there is shown a schematic diagram of a first driving structure and a light absorbing and reflecting film layer according to the present application. The first driving structure160includes a driving mechanism, a first bearing and a second bearing. The first bearing and the second bearing are respectively arranged on both sides of the light absorbing and reflecting film layer130. When the light absorbing and reflecting film layer130moves from the second bearing in the direction of the first bearing, the first bearing serves as a transmission shaft, and the second bearing serves as a driven shaft. When the light absorbing and reflecting film layer130moves from the first bearing to the second bearing, the first bearing serves as the driven shaft and the second bearing serves as the transmission shaft. The driving mechanism may drive the first bearing and the second bearing to rotate simultaneously or in a time-sharing manner to drive the light absorbing and reflecting film layer to move.

It may be appreciated that a part of light absorbing and reflecting film layer130needs to be rolled up on the first bearing and the second bearing, so that during the rotation of the first bearing or the second bearing, the light absorbing and reflecting film layer130is driven may be move. In actual use, in particular, the distance by which that the light absorbing and reflecting film layer130moves is very small, which is related to the width of the hollow portion151. It is merely needed to realize the configuration that each light absorbing and reflecting structure134completely occupies the respective hollow portion151until the same light absorbing and reflecting structure134does not overlap the hollow portion151at all; that is, it is merely needed to move by a distance of the width of one hollow portion151.

In order to prevent the light absorbing and reflecting film layer130from breaking, the light absorbing and reflecting film layer130structure may be arranged on a transparent film, such as film glue or other transparent films. One or two layers of transparent films may be arranged, and an array of light absorbing and reflecting structures134may be arranged on the transparent film(s). In particular, the movement of the light absorbing and reflecting film layer130may be controlled by rolling the transparent film(s) up on the first bearing and the second bearing.

In this embodiment, the light absorbing and reflecting film layer130and the first reflective sheet140may be configured as a composite structural film layer. That is, the first reflective sheet140may be provided with a groove or a through slot at the position corresponding to each light absorbing and reflecting structure134, where there is no film layer here. Thus, the light absorbing and reflecting structure134may be arranged in the groove, thus forming the first reflective sheet140integrated with the light absorbing and reflecting structure134, so that the first reflective sheet140is drivingly connected to the first bearing and the second bearing to achieve the function of controlling the movement of the light absorbing and reflecting structure134.

In another embodiment, the backlight module100may further include a second driving structure. The second driving structure may be consistent with the first driving structure. The second driving structure is used to drive the second reflective sheet150to move relative to the light absorbing and reflecting film layer130, so that the facing area A between each light absorbing and reflecting structure134and the respective hollow portion151changes. The second driving structure may be consistent with that of the first driving structure160. The difference is that the second driving structure is used to drive the second reflective sheet150to move. The movement of the second reflective sheet150may also change the area of each light absorbing and reflecting structure, thereby adjusting the intensity of the reflected blue light.

In this embodiment, the number, density, thickness and other designs of the light absorbing and reflecting structures134provided in any of the above embodiments can be used in combination to better solve the yellowing problem of the display panel.

Embodiment 4

Referring toFIG.7, there is shown a schematic diagram illustrating a display device according to the present application. This application further discloses a display device. The display device200includes a display panel210and the backlight module100described in any of the above embodiments. The backlight module100provides a light source for the display panel210.

In this application, in an edge-type backlight module, the second surface of the light guide plate is provided with a light absorbing and reflecting film layer, which absorbs light of some wavelengths and then reflects blue light to enhance the proportion of blue light in the display panel, thus making up for the yellowing problem of the panel display. In this solution, since the light absorbing and reflecting film layer is arranged below the light guide plate, it will not affect the transmittance of the display panel, and it may also reduce the loss of light as much as possible when otherwise passing through more film layers. More importantly, it can absorb excess light and reflect blue light to enhance the display effect of the display panel, so as to overcome the problem of yellowing of the display panel without affecting the transmittance.

It should be noted that the inventive concept of this application can be formed into many embodiments, but the length of the application document is limited and so these embodiments cannot be enumerated one by one. The technical features can be arbitrarily combined to form a new embodiment, and the original technical effect may be enhanced after the various embodiments or technical features are combined.

The foregoing description is merely a further detailed description of this application made with reference to some specific illustrative embodiments, and the specific implementations of this application will not be construed to be limited to these illustrative embodiments. For those having ordinary skill in the technical field to which this application pertains, numerous simple deductions or substitutions may be made without departing from the concept of this application, which shall all be regarded as falling in the scope of protection of this application.