Backlight module and an optical slice unit support device thereof

The present invention provides a backlight module and a support device for a sheet-form optical element contained within the backlight module. The backlight module mainly includes a frame, a support device and the sheet-form optical element disposed within the frame. The support device includes a support portion and a positioning portion. The support portion has a support end and a connection end. The support end extends into the space within the frame, and supports the bottom end of the sheet-form optical element. The positioning portion has a first end, a second end and a bend portion connecting the first end with the second end. The first end connects to the connection end of the support portion, and an included angle exists between the first end and the support portion. The positioning portion of the support device is inset in the frame to provide a support force for the support portion.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates generally to a backlight module and a support device for an optical slice unit/a sheet-form optical element contained therein, and more particularly to a backlight module for a liquid crystal display (LCD) device and a support device for a sheet-form optical element contained therein.

2. Description of the Prior Art

Backlight modules are used extensively in liquid crystal display (LCD) devices, computers keyboards, cell phone buttons, billboards and other devices requiring light sources to provide the necessary flat light sources for these devices. Especially, the recent market demand for LCD devices has increased considerably. In order to match functional and exterior requirements of the LCD devices, the backlight module design for LCD devices has gradually become multidimensional.

FIG. 1shows a schematic view of a conventional LCD device. As shown inFIG. 1, the LCD device comprises a backlight module10, a liquid crystal (LC) panel15and a front frame1.7disposed on the backlight module10. The backlight module10comprises a bottom bezel21, a reflector23, a frame30, a light guide plate13, a light source module11and optical films59. The light guide plate13is disposed within the frame30, and the light source module11is disposed between the light guide plate13and the frame30and corresponds to a bottom end of the light guide plate13. The optical films59are disposed above the light guide plate13, and the reflector23and the bottom bezel21are disposed under the frame30and the light guide plate13.

When the assembly of the LCD device shown inFIG. 1is complete and is disposed uprightly, the light guide plate13has a gravity pressing against the bottom end of the frame30. In order to prevent the light guide plate13from sliding downward to press against or damage the light source module11, the side-wall end of the frame30extends inwardly to form a stop plate31. Through forming the stop plate31, the frame30immobilizes the light guide plate13and prevents the light guide plate13from sliding downward. Generally speaking, the stop plate31is integratedly formed with the frame30by employing injection molding. Consequently, the material of the stop plate31is usually the same as that of the frame30.

As users increasingly demand more visual effect, the dimensions of the LC panel15have increased as well. When the size of the LC panel15is increased, the size of the overall backlight module10and the light guide plate13have to increase accordingly. After the size of the light guide plate13is increased, the stop plate31shown inFIG. 1also needs to bear a larger load. However, when the stop plate31formed integratedly with the frame30and being plastic made bears a light guide plate13having larger dimensions, it is susceptible to structural damage due to insufficient bearing capacity, and further damages the light source module below.

SUMMARY OF THE INVENTION

It is an object of the present invention to provide a backlight module having a higher structural stability.

It is another object of the present invention to provide a backlight module having a simple and easy assembly process.

It is a further object of the present invention to provide a support device used in a backlight module for supporting and positioning an optical slice unit/a sheet-form optical element in the backlight module.

It is yet another object of the present invention to provide a support device used in a backlight module having a higher bearing capacity.

The backlight module in accordance with the present invention mainly includes a light source module, a frame, a support device and an optical slice unit/a sheet-form optical element. The sheet-form optical element is disposed within the frame. The support device engages partially with the frame and supports the bottom end of the sheet-form optical element. The light source module is preferably disposed corresponding to the bottom end of the sheet-form optical element, and is situated between the bottom side of the frame and the bottom end of the sheet-form optical element.

The support device comprises a support portion and a positioning portion. The support portion has a support end and a connection end. The support end extends into the space within the frame and supports the bottom end of the sheet-form optical element. The positioning portion extends from the connection end of the support portion to provide the support force necessary for the support portion. The positioning portion has a first end, a second end and a bend portion connecting the first end with the second end. The first end connects to the connection end of the support portion, and an included angle exists between the first end and the support portion. Moreover, the support device is preferably made of metal materials, and the thickness of the support device preferably ranges between 0.2 millimeter (mm) and 0.8 mm.

The positioning portion of the support device is inset in the frame, and the support portion extends from the frame into the space within the frame. The frame includes side walls, and the positioning portion is inset in the side wall. The side wall of the frame preferably has a positioning groove and an edge. The cross sectional shape of the positioning groove is similar to that of the positioning portion of the support device, and the positioning portion is contained within the positioning groove to be inset in the side wall. Through disposing the bend portion, the support device cannot disengage from the positioning groove and from the side wall through any other directions besides the original inset direction of the positioning portion. When the support portion of the support device receives an external force produced by the sheet-form optical element, the support portion passes on and distributes the received force to the frame through the positioning portion.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

The present invention provides a backlight module and a support device for an optical slice unit/a sheet-form optical element contained within the backlight module. For the preferred embodiment, the backlight module is used in a liquid crystal display (LCD) device. However, in other embodiments, the backlight module may be used in computer keyboards, cell phone buttons, billboards and other devices requiring flat light sources. Specifically speaking, the present invention further includes a LCD device using the backlight module. In the preferred embodiment, the LCD device in accordance with the present invention includes a color LCD device. However, in other embodiments, the LCD device according to the present invention may include a monochromatic LCD device. The above LCD device refers generally to display devices using liquid crystal (LC) panels, including LC monitors of household LCTVs, personal computers and laptops, and LC display screens of cell phones and digital cameras, etc.

As the embodiment shown inFIG. 2, the LCD device comprises a backlight module100, a LC panel150and an upper cover170. The backlight module100mainly includes a light source module110, a frame300, a support device700and an optical slice unit/a sheet-form optical element130. The sheet-form optical element130is disposed within the frame300. The support device700connects to the frame300and supports a bottom end of the sheet-form optical element. As shown inFIG. 2, the support device700is preferably inset partially into the frame300. The light source module110is preferably disposed corresponding to the bottom end of the sheet-form optical element, and is situated between the bottom side of the frame300and the bottom end of the sheet-form optical element130. In the preferred embodiment, the support device700positions the sheet-form optical element130and prevents the sheet-form optical element from moving downward to press against or damage the light source module110. Moreover, the LCD device may further include a bottom bezel210and a reflector sheet230. The bottom bezel210is disposed below the frame300and the sheet-form optical element130, and the reflector sheet230is disposed between the bottom bezel210and the sheet-form optical element130. In addition, the bottom bezel210may be used as a lamp reflector or a lamp cover to improve the efficiency of the light usage.

The light source module110preferably includes a lamp tube111and lamp tube holding members113. However, in other embodiments, the light source module110may use point light sources, such as light emitting diodes (LEDs). The sheet-form optical element130preferably includes a light guide panel. The above sheet-form optical element130includes planiform optical elements, such as optical plates or optical films. In the embodiment shown inFIG. 2, the sheet-form optical element130is a light guide panel having optical microstructures on the surface. In this embodiment, the optical microstructures having V-shaped cross sections are formed on the upper surface of the light guide panel; however, in other embodiments, the optical microstructures may be other-shaped prism structures formed on the lower surface of the light guide panel, or formed on the both sides of the light guide panel. In addition, the sheet-form optical element130may include a light guide panel having no microstructures thereon, the sheet-form optical element130may also include a diffusion film, brightness enhancing film, optical films590or other sheet-form optical element130.

As shown inFIG. 3aandFIG. 3b, the support device700includes a support portion710and a positioning portion730. The support portion710has a support end711and a connection end713. As shown inFIG. 3b, the support portion710includes an extending strip structure, and the support end711and the connection end713are situated at opposite ends respectively of the strip structure. The support end711extends into a space within the frame300and supports the bottom end of the sheet-form optical element130. The positioning portion730extends from the connection end713of the support portion710, and is preferably formed integratedly with the support portion710. The positioning portion730has a first end731, a second end732and a bend portion735connecting the first end731with the second end732. The first end731connects to the connection end713of the support portion710, and an included angle exists between the first end731and the support portion710. In the embodiment shown inFIG. 4a, the first end731of the positioning portion730is perpendicular to the support portion710. However, in other embodiments, an acute angle or an obtuse angle may exist between the first end731of the positioning portion730and the support portion710depending on the space limits or mechanics design requirements.

In the preferred embodiment, the support device700is integratedly formed. Moreover, the support device700is preferably made of metal materials. When a metal-made strip structure is used to make the support device700, the support portion710and the positioning portion730can be formed by employing bending, stamping or punching. In order to reach more desirable support strength, the thickness of the support device700is preferably between 0.2 millimeter (mm) and 0.8 mm. However, in other embodiments, the support device700may be formed by injection molding high strength polymer materials or other methods.

As shown inFIG. 3aandFIG. 4a, the positioning portion730of the support device700is inset in the frame300, and the support portion710extends from the frame300into the space within the frame300. In this preferred embodiment, the frame300includes side walls310, and the positioning portion730is inset in the side walls310. In other words, the support device700cannot disengage from the side wall310through any other directions besides the original inset direction of the positioning portion730. In this embodiment, the frame300has a pair of side walls310where the support devices700are inset therein respectively. The pair of the disposed support devices700support two ends respectively of the bottom end of the sheet-form optical element130to achieve and maintain stable support effect.

Furthermore, as shown inFIG. 4b, each of the side walls310of the frame300preferably has a positioning groove311and an edge313. The cross sectional shape of the positioning groove311is similar to that of the positioning portion730of the support device700, and the positioning portion730is contained within the positioning groove311to be inset in the side wall310. In this embodiment, since the light source module is disposed at the bottom end of the frame300, the edge313of the side wall310corresponds to one end of the light source module110. The positioning groove311has an open end315on the edge313of the side wall310. When the positioning portion730of the support device700is inset in the positioning groove311, the second end of the positioning portion730corresponds to the open end315. In addition, the support portion710of the support device700extends from the second end of the positioning portion730along the edge313of the side wall310into the space within the frame300.

As the embodiment shown inFIG. 4aandFIG. 4b, the side wall310has an inner-wall surface317within the positioning groove311. In other words, the inner-wall surface is formed on one side within the positioning groove311. Protruding parts319are formed on the inner-wall surface317. The protruding parts319touch against the positioning portion730of the support device700. Through disposing the protruding parts319, the positioning portion730is held firmly within the positioning groove311to prevent the positioning portion730from moving or rotating within the positioning groove311. Moreover, as shown inFIG. 4b, the inner-wall surface317is preferably the outer-side inner-wall surface corresponding to the positioning groove311. The above outer-side inner-wall surface refers to the inner-wall surface317closer to the outside of the frame300and further away from the sheet-form optical element130. Consequently, the protruding parts319formed on the outer-side inner-wall surface touch against the outside of the positioning portion730. However, in other embodiments, the protruding parts319may be formed on the inner-side inner-wall surface317, or formed respectively on the outer-side and inner-side inner-wall surface317.

Furthermore, the positioning groove311includes a gap320between the inner-wall surface317and the positioning portion730. In other words, the positioning portion730is disposed in the positioning groove311with a gap320formed between the inner-wall surface317and the positioning groove311since the protruding part319protrudes from the inner-wall surface317into the positioning groove311.

As shown inFIG. 4aandFIG. 4b, two protruding parts319are formed on the inner-wall surface317. One protruding part is formed close to the open end315of the positioning groove311. This protruding part319touches against the outer side of the first end731of the positioning portion730of the support device700. When the support portion710of the support device700receives an external force generated by the sheet-form optical element130, this protruding part319gives intensively an opposite reaction force to the first end731of the positioning portion730to prevent the support device700from rotating or linear displacement. However, in other embodiments, as shown inFIG. 4c, when the cross sectional shape of the positioning portion730of the support device700is the same as the positioning groove311, it is not needed to dispose the protruding parts319on the inner-wall surface317of the positioning groove311. Because the thickness of the positioning portion730is the same as the width of the positioning groove311, the inner-wall surface317of the positioning groove311has inherent capability for holding the positioning portion730and prevents the positioning portion730from shaking within the positioning groove311. When no protruding parts319are disposed, outer-side inner-wall surface also gives an opposite reaction force to the outer side of the positioning portion730to achieve force balance.

The positioning portion730of the support device700has a bend portion735for connecting the first end731with the second end732. In the embodiment shown inFIG. 3aandFIG. 3b, the bend portion735mainly includes an included-angle bending portion. In other words, an acute angle, a right angle or an obtuse angle exists between the first end731and the second end732. In the preferred embodiment, as shown inFIG. 4a, the included-angle bending portion forming the bend portion is a 90 degree right-angle bending portion. And the first end731extending direction of the positioning portion730is perpendicular to the second end732extending direction. In addition, the second end732extending direction of the positioning portion730is opposite to the support end711extending direction of the support portion710.

Through disposing the bend portion735, the support device700cannot disengage from the positioning groove311and from the side wall310through any other directions besides the original inset direction of the positioning portion730. When the support portion710of the support device700receives an external force produced by the sheet-form optical element130, the support portion710passes on and distributes the force to the frame300through the positioning portion730. As shown inFIG. 4a, when the external force produced by the sheet-form optical element130has a downward component force perpendicular to the support portion710, the second end732of the positioning portion730parallel to the support portion710provides a resistance force to balance the component force of this external force.

FIG. 5aandFIG. 5bshow another embodiment of the present invention. In this embodiment, the bend portion735also includes an included-angle bending portion. However, the difference from the previous embodiment is that the second end732extending direction of the positioning portion730is the same as the support end711extending direction of the support portion710. This design also enables the support device700to be inset in the positioning groove311, and to pass on and distribute the received external force to the frame300.

FIG. 6aandFIG. 6bshow a further embodiment of the present invention. In this embodiment, the bend portion735mainly includes a curved portion; in other words, a curved portion exists between the first end731and the second end732. In the preferred embodiment, as shown inFIG. 6aandFIG. 6b, the round angle forming the bend portion735is close to 180 degrees. And the first end731extending direction of the positioning portion730roughly parallels to the second end732extending direction. This design enables the support device700to be inset in the positioning groove311, and to pass on and distribute the received external force to the frame300.

From the foregoing, it shall be appreciated that specific embodiments of the invention have been described herein for purposes of illustration, but that various modifications and alterations may be made by those skilled in the art without deviating from the spirit and scope of the invention. For example, it shall be understood that there is no intention to limit the positioning portion730to the specific forms disclosed, but on the contrary, the invention is to cover all modifications, alternate constructions and equivalents falling within the spirit and scope of the invention. Accordingly, the invention is not limited except as by the appended claims.