Backlight module

The present invention provides a backlight module, which includes a backplane, a backlight source arranged inside the backplane, a reflector plate arranged inside the backplane, a light guide plate arranged on the reflector plate, and a mold frame mounted to the backplane. The mold frame forms a projection. The backplane forms a retention slot corresponding to the projection. The projection and the retention slot mate each other through interference fitting, whereby with the interference fitting between the projection and the retention slot, the mold frame is fixedly connected to the backplane. The backlight module uses a projection formed on the mold frame and a retention section formed in the backplane to mate the projection through interference fitting pawl section so as to fixedly mount the mold frame to the backplane through interference-fitting connection thereby showing a simple structure, being easy to assemble, effectively saving time, and thus controlling the cost.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to the field of liquid crystal displaying, and in particular to a backlight module.

2. The Related Arts

Liquid crystal display (LCD) has a variety of advantages, such as thin device body, low power consumption, and being free of radiation, and is thus widely used. Most of the LCDs that are currently available in the market are backlighting LCDs, which comprise a liquid crystal panel and a backlight module. The operation principle of the liquid crystal panel is that liquid crystal molecules are interposed between two parallel glass substrates and a plurality of vertical and horizontal fine electrical wires are arranged between the two glass substrates, whereby the liquid crystal molecules are controlled to change direction by application of electricity in order to refract light emitting from the backlight module for generating images. Since the liquid crystal panel itself does not emit light, light must be provided by the backlight module in order to normally display images. Thus, the backlight module is one of the key components of an LCD. The backlight module can be classified in two types, namely side-edge backlight module and direct backlight module, according to the position where light gets incident. The direct backlight module comprises a light source, such as a cold cathode fluorescent lamp (CCFL) or a light-emitting diode (LED), which is arranged at the back side of the liquid crystal panel to form a planar light source that directly provides lighting to the liquid crystal panel. The side-edge backlight module comprises a backlight source of LED light bar arranged at an edge of a backplane to be located rearward of one side of the liquid crystal panel. The LED light bar emits light that enters a light guide plate (LGP) through a light incident face of the light guide plate and is projected out through a light emergence face of the light guide plate, after being reflected and diffused, to thereby transmit through an optic film assembly and form a planar light source for the liquid crystal panel.

A conventional side-edge backlight module comprises a backplane, a backlight source arranged inside the backplane, a reflector plate arranged inside the backplane, a light guide plate arranged above the reflector plate, an optic film assembly arranged on the light guide plate, and a mold frame mounted to the backplane. The backplane and the mold frame are often fixed together through bolts. Such a process of assembling requires the use of a separate tool so that assembling and disassembling are both difficult and consume work hours.

SUMMARY OF THE INVENTION

An object of the present invention is to provide a backlight module, which comprises a backplane and a mold frame that are assembled and fixed together through interference-fitting connection, showing a simple structure and being easy to assemble.

To achieve the object, the present invention provides a backlight module, which comprises a backplane, a backlight source arranged inside the backplane, a reflector plate arranged inside the backplane, a light guide plate arranged on the reflector plate, and a mold frame mounted to the backplane. The mold frame forms a projection. The backplane forms a retention slot corresponding to the projection. The projection and the retention slot are mateable with each other through interference fitting, whereby with the interference fitting between the projection and the retention slot, the mold frame is fixedly connected to the backplane.

The projection has a cross-section that is of a trapezoidal shape.

The retention slot has a shape corresponding to the shape of the projection and the retention slot has a size that is smaller than size of the projection.

The backplane comprises a bottom board and a first side board.

The retention section is formed in the first side board.

The mold frame comprises a top board and a second side board.

The projection is formed on an end face of a free end of the second side board.

The backlight module further comprises a heat dissipation plate arranged under the reflector plate, a diffusion plate arranged on the light guide plate, and a prism plate arranged on the diffusion plate.

The backlight source comprises a linear light source.

The present invention also provides a backlight module, which comprises a backplane, a backlight source arranged inside the backplane, a reflector plate arranged inside the backplane, a light guide plate arranged on the reflector plate, and a mold frame mounted to the backplane, the mold frame forming a projection, the backplane forming a retention slot corresponding to the projection, the projection and the retention slot being mateable with each other through interference fitting, whereby with the interference fitting between the projection and the retention slot, the mold frame is fixedly connected to the backplane; and

wherein the projection has a cross-section that is of a trapezoidal shape;

wherein the retention slot has a shape corresponding to the shape of the projection and the retention slot has a size that is smaller than size of the projection;

wherein the backplane comprises a bottom board and a first side board;

wherein the retention section is formed in the first side board;

wherein the mold frame comprises a top board and a second side board;

wherein the projection is formed on an end face of a free end of the second side board;

further comprising a heat dissipation plate arranged under the reflector plate, a diffusion plate arranged on the light guide plate, and a prism plate arranged on the diffusion plate; and

wherein the backlight source comprises a linear light source.

The efficacy of the present invention is that the present invention provides a backlight module, which comprises a mold frame forming a projection and a backplane forming a retention section that mates the projection through interference fitting so as to fixedly mount the mold frame to the backplane through interference-fitting connection thereby showing a simple structure, being easy to assemble, effectively saving time, and thus controlling the cost.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring toFIG. 1, the present invention provides a backlight module, which comprises a backplane10, a backlight source20arranged inside the backplane10, a reflector plate30arranged inside the backplane10, a light guide plate40arranged on the reflector plate30, and a mold frame50mounted to the backplane10. The mold frame50forms a projection502. The backplane10forms a retention slot102corresponding to the projection502. The projection502and the retention slot102mate each other through interference fitting, whereby with the interference fitting between the projection502and the retention slot102, the mold frame50is fixedly connected to the backplane10.

In the instant embodiment, the projection502has a cross-section that is of a trapezoidal shape. The retention slot102has a shape corresponding to the shape of the projection502, but the retention slot102has a size that is slightly smaller than the size of the projection502. To assemble, the mold frame50is directly pressed down toward the backplane10to have the projection502fit into the retention slot102in such a way that interference fitting is established between the projection502and the retention slot102thereby fixedly connecting the mold frame50to the backplane10. The process of mounting is simple and time can be saved.

The backplane10comprises a bottom board12and a first side board14. The retention slot102is formed in the first side board14. The mold frame50comprises a top board52and a second side board54. The projection502is formed on an end face of a free end of the second side board54.

The backlight module according to the present invention also comprises a heat dissipation plate60arranged under the reflector plate30, a diffusion plate70arranged on the light guide plate40, and a prism plate80arranged on the diffusion plate70. The backlight source20comprises a linear light source, which emits light of which a portion directly transmits through an incidence surface of the light guide plate40to enter the interior of the light guide plate40and a remaining portion is reflected by the reflector plate30to get into the light guide plate40. The light propagates through the light guide plate40as being simultaneously subjected to total reflection and refraction and is further subjected to diffusion through the diffusion plate70and the prism plate80to thereby provide a uniformly distributed planar light source.

In summary, the present invention provides a backlight module, which comprises a mold frame forming a projection and a backplane forming a retention section that mates the projection through interference fitting so as to fixedly mount the mold frame to the backplane through interference-fitting connection thereby showing a simple structure, being easy to assemble, effectively saving time, and thus controlling the cost.