CN203811949U - Backlight module and liquid crystal display device - Google Patents

Abstract

The utility model provides a backlight module and a liquid crystal display device, and relates to the technical field of liquid crystal display. The liquid crystal display device comprises a first polarizing film, a display panel and the backlight module. The display panel is positioned below the first polarizing film, and the backlight module is positioned below the display panel. The backlight module comprises a light guide plate. The light guide plate is made of zero zero-birefringence polymers materials, and prism-shaped structures are arranged at the bottom of the light guide plate; a light source and a reflective film are arranged on a side surface of the light guide plate, and the sides, except for the side which faces the light guide plate, of the light source are surrounded by the reflective film; a reflection type polarizer is arranged between the light source and the light guide plate; a reflective plate is arranged below the light guide plate. The backlight module and the liquid crystal display device have the advantage that the utilization rate of emergent light of the backlight module can be improved.

Description

Backlight module and liquid crystal display device

technical field

The utility model relates to the technical field of liquid crystal display, in particular to a backlight module and a liquid crystal display device.

Background technique

The display panel in the liquid crystal display device cannot emit light itself, and the display panel can only form different gray scales by controlling the brightness of the light passing through, which needs the support of the backlight module. Usually the light emitted by the backlight module is natural light, including polarized light in various polarization directions. The display panel is provided with a polarizer on the side close to the backlight module, so the light that the display panel can accept is only polarized light in a certain polarization direction. The polarized light in other polarization directions cannot pass through the polarizer, which causes waste of the polarized light in this polarization direction, so that the utilization rate of the light emitted by the backlight module is low.

Utility model content

The utility model provides a backlight module and a liquid crystal display device, which can improve the utilization rate of light emitted by the backlight module.

On the one hand, the utility model provides a backlight module, comprising: a light guide plate, the light guide plate is made of a zero-zero birefringence polymer material, the bottom surface of the light guide plate is a prism-shaped structure; the side surface of the light guide plate A light source and a reflective film are provided, and the light source is surrounded by the reflective film except for the side facing the light guide plate; a reflective polarizer is arranged between the light source and the light guide plate; A reflector is provided below.

Specifically, the light source is LED or CCFL.

Specifically, the reflective plate is a specular reflective plate.

On the other hand, the utility model also provides a liquid crystal display device, comprising: a first polarizer, a display panel located under the first polarizer, a backlight module located under the display panel; the backlight module It includes: a light guide plate, the light guide plate is made of zero-zero birefringence polymer material, the bottom surface of the light guide plate is a prism structure; the side of the light guide plate is provided with a light source and a reflection film, and the light source is directed towards One side of the light guide plate is surrounded by the reflection film; a reflective polarizer is arranged between the light source and the light guide plate; a reflection plate is arranged under the light guide plate.

Specifically, a second polarizer is arranged between the display panel and the light guide plate;

The direction of the transmission axis of the reflective polarizer is the same as the direction of the transmission axis of the second polarizer.

Specifically, the light source is LED or CCFL.

Preferably, the reflective plate is a specular reflective plate.

In the backlight module and the liquid crystal display device provided by the utility model, the reflective polarizer in the backlight module and the circular reflection of the reflective film can convert the second polarized light in the natural light emitted by the light source into the first polarized light, and the first polarized light After being transmitted through the reflective polarizer and guided by the light guide plate made of zero-zero birefringence material, it is still the first polarized light. Compared with the existing technology, most of the light in the light source can be converted to be used by the display panel Light with a specific polarization direction, thereby improving the utilization rate of light emitted by the backlight module.

Description of drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the accompanying drawings that need to be used in the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description These are only some embodiments of the utility model, and those skilled in the art can also obtain other drawings based on these drawings without creative work.

Fig. 1 is a schematic structural view of a backlight module in an embodiment of the present invention;

FIG. 2 is a schematic structural view of a light source and a reflective polarizer in the backlight module of FIG. 1;

3 is a schematic structural view of a liquid crystal display device in an embodiment of the present invention;

FIG. 4 is a schematic structural diagram of another liquid crystal display device in an embodiment of the present invention.

Detailed ways

The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. example. Based on the embodiments of the present utility model, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the scope of protection of the present utility model.

As shown in Figure 1, the embodiment of the present utility model provides a backlight module, including: a light guide plate 11, the light guide plate 11 is made of zero zero birefringence polymer (Zero Zero-Birefringence Polymers) material, the bottom surface of the light guide plate 11 It is a prism-like structure; the side of the light guide plate 11 is provided with a light source 12 and a reflective film 13, and the light source 12 is surrounded by the reflective film 13 except the side facing the light guide plate 11; a reflective polarizer is arranged between the light source 12 and the light guide plate 11 device 14; a reflection plate 15 is provided below the light guide plate 11.

When the backlight module provides the backlight, as shown in Figure 2, the light source 12 is turned on, and the light emitted by the light source 12 is natural light, which can be divided into light with two polarization directions, the first polarized light and the second polarized light, as shown in Figure 2. Arrows and non-shaded arrows represent the propagation directions of the first polarized light and the second polarized light respectively, and a reflective polarizer 14 is arranged between the light source 12 and the light guide plate 11, and the reflective polarizer 14 can transmit light in one polarization direction. , light reflection of another polarization direction, the first polarized light in the natural light emitted by the light source 6 can pass through the reflective polarizer 14, the second polarized light is reflected by the reflective polarizer 14, and the reflected second polarized light passes through the reflective film 12 and reflective polarizer 14 after multiple cycles of reflection, the second polarized light can be converted into the first polarized light, and the conversion rate is high, the first polarized light transmitted from the reflective polarizer 14 enters the light guide plate 11, guides The light plate 11 is made of a zero-zero birefringence polymer material, and the zero-zero birefringence polymer material exhibits isotropic properties under the condition of being subjected to an external force and not being subjected to an external force, and is made of a zero-zero birefringence polymer material The light guide plate 11 can guide the light without changing or slightly changing the polarization state of the light. The prism-like structure on the bottom surface of the light guide plate 11 can reflect the first polarized light, which is transmitted from the reflective polarizer 14 on the side of the light guide plate 11. The first polarized light enters the light guide plate 11 and is reflected by the prism structure so that the first polarized light can be emitted from the front of the light guide plate 11, and the reflection plate 15 below the light guide plate 11 can reflect first polarized light. The backlight module in this embodiment only emits the first polarized light, so the polarizer between the display panel and the light guide plate in the prior art can be omitted, and the display panel directly uses the first polarized light emitted by the backlight module. Of course, a polarizer can also be arranged between the light guide plate and the display panel, and the transmission axis direction of the reflective polarizer is set to be consistent with the transmission axis direction of the polarizer, so that the first polarized light can directly pass through the polarizer, Thus used by the display panel.

In the backlight module provided by the utility model, the circular reflection effect of the reflective polarizer and the reflective film in the backlight module can convert the second polarized light in the natural light emitted by the light source into the first polarized light, and the first polarized light is transmitted through the reflective type After the polarizer and the light guide plate made of zero-zero birefringence material guide the light, it is still the first polarized light. Compared with the existing technology, most of the light in the light source is converted into a specific polarization direction that can be used by the display panel light, thereby improving the utilization rate of the light emitted by the backlight module.

Specifically, the light source 12 may be a light emitting diode (Light Emitting Diode, LED for short) or a cold cathode fluorescent lamp (Cold Cathode Fluorescent Lamp, CCFL for short) or the like.

Preferably, as shown in FIG. 1 , the reflective plate 15 may be a specular reflective plate. When the specular reflector reflects polarized light, it does not change or slightly changes the polarization state of the light, so that the polarized light entering the light guide plate after reflection has the same polarization direction as the original polarized light, so as to ensure that the light utilization rate will not be reduced.

As shown in Figure 3, the utility model also provides a kind of liquid crystal display device, comprising: a first polarizer 21, a display panel 2 positioned below the first polarizer 21, a backlight module positioned at the bottom of the display panel 2; the backlight module It includes: a light guide plate 11, the light guide plate 11 is made of zero-zero birefringence polymer material, the bottom surface of the light guide plate 11 is a prism-like structure; One side is surrounded by a reflective film 13; a reflective polarizer 14 is provided between the light source 12 and the light guide plate 11; a reflective plate 15 is provided below the light guide plate 11.

When the backlight module provides the backlight, as shown in Figure 2, the light source 12 is turned on, and the light emitted by the light source 12 is natural light, which can be divided into light with two polarization directions, the first polarized light and the second polarized light, as shown in Figure 2. Arrows and non-shaded arrows represent the propagation directions of the first polarized light and the second polarized light respectively, and a reflective polarizer 14 is arranged between the light source 12 and the light guide plate 11, and the reflective polarizer 14 can transmit light in one polarization direction. , light reflection of another polarization direction, the first polarized light in the natural light emitted by the light source 6 can pass through the reflective polarizer 14, the second polarized light is reflected by the reflective polarizer 14, and the reflected second polarized light passes through the reflective film 12 and reflective polarizer 14 after multiple cycles of reflection, the second polarized light can be converted to the first polarized light, and the conversion rate is high, the light emitted by the light source can pass through the reflective polarizer 14, and the transmitted light Both are the first polarized light, the first polarized light transmitted from the reflective polarizer 14 enters the light guide plate 11, the light guide plate 11 is made of zero-zero birefringence polymer material, and the zero-zero birefringence polymer material is subjected to external force and no Under the condition of external force, they all show isotropic properties, and the light guide plate 11 made of zero-zero birefringence polymer material can guide light without changing or slightly changing the polarization state of light. The prism-shaped structure on the bottom surface of the light plate 11 can reflect the first polarized light, and the first polarized light transmitted from the reflective polarizer 14 on the side of the light guide plate 11 enters the light guide plate 11, and the reflection by the prism-shaped structure can make the first polarized light pass through the light guide plate. 11 , the reflection plate 15 under the light guide plate 11 can reflect the first polarized light emitted from the light guide plate 11 toward the reflection plate 15 . The backlight module in this embodiment only emits the first polarized light, so the polarizer between the display panel 2 and the light guide plate 11 in the prior art can be omitted, and the display panel 2 directly utilizes the first polarized light emitted by the backlight module.

In the liquid crystal display device provided by the utility model, the circular reflection effect of the reflective polarizer and the reflective film in the backlight module can convert the second polarized light in the natural light emitted by the light source into the first polarized light, and the first polarized light is transmitted through the reflective type After the polarizer and the light guide plate made of zero-zero birefringence material guide the light, it is still the first polarized light. Compared with the existing technology, most of the light in the light source is converted into a specific polarization direction that can be used by the display panel light, thereby improving the utilization rate of the light emitted by the backlight module.

Optionally, in addition to the above structure of omitting the polarizer between the display panel and the light guide plate, as shown in FIG. 4 , a second polarizer 22 is arranged between the display panel 2 and the light guide plate 11; The direction of the transmission axis of 14 is the same as the direction of the transmission axis of the second polarizer 22 . The polarized light emitted by the backlight module can directly pass through the second polarizer 22 and be used by the display panel.

Specifically, the light source 12 can be LED or CCFL.

Preferably, as shown in FIG. 3 , the reflective plate 15 may be a specular reflective plate. When the specular reflector reflects polarized light, it does not change or slightly changes the polarization state of the light, so that the polarized light entering the light guide plate after reflection has the same polarization direction as the original polarized light, so as to ensure that the light utilization rate will not be reduced. .

The above-mentioned liquid crystal display device can specifically be: any product or component with a liquid crystal display function such as a liquid crystal panel, a mobile phone, a tablet computer, a television set, a monitor, a notebook computer, a digital photo frame, a navigator, and the like.

In the liquid crystal display device provided by the utility model, the circular reflection effect of the reflective polarizer and the reflective film in the backlight module can convert the second polarized light in the natural light emitted by the light source into the first polarized light, and the first polarized light is transmitted through the reflective type After the polarizer and the light guide plate made of zero-zero birefringence material guide the light, it is still the first polarized light. Compared with the existing technology, most of the light in the light source is converted into a specific polarization direction that can be used by the display panel light, thereby improving the utilization rate of the light emitted by the backlight module.

The above is only a specific embodiment of the present utility model, but the scope of protection of the present utility model is not limited thereto. Anyone familiar with the technical field can easily think of changes or changes within the technical scope disclosed by the utility model Replacement should be covered within the protection scope of the present utility model. Therefore, the protection scope of the present utility model should be based on the protection scope of the claims.

Claims (7)

1. A backlight module, characterized in that, comprising: A light guide plate, the light guide plate is made of a zero-zero birefringence polymer material, and the bottom surface of the light guide plate is a prism-like structure; The side of the light guide plate is provided with a light source and a reflective film, and the light source is surrounded by the reflective film except for the side facing the light guide plate; A reflective polarizer is arranged between the light source and the light guide plate; A reflection plate is arranged below the light guide plate. 2. The backlight module according to claim 1, characterized in that, The light source is LED or CCFL. 3. The backlight module according to claim 1, characterized in that, The reflector is a specular reflector. 4. A liquid crystal display device, characterized in that, comprising: a first polarizer, a display panel located below the first polarizer, and a backlight module located below the display panel; The backlight module includes: A light guide plate, the light guide plate is made of a zero-zero birefringence polymer material, and the bottom surface of the light guide plate is a prism-like structure; The side of the light guide plate is provided with a light source and a reflective film, and the light source is surrounded by the reflective film except for the side facing the light guide plate; A reflective polarizer is arranged between the light source and the light guide plate; A reflection plate is arranged below the light guide plate. 5. The liquid crystal display device according to claim 4, wherein: A second polarizer is arranged between the display panel and the light guide plate; The direction of the transmission axis of the reflective polarizer is the same as the direction of the transmission axis of the second polarizer. 6. The liquid crystal display device according to claim 4 or 5, characterized in that, The light source is LED or CCFL. 7. The liquid crystal display device according to claim 4 or 5, characterized in that, The reflector is a specular reflector.