This application claims priority to Taiwan Patent Application No. 091117124 entitled “Lamp Module and Back Light Device Having the Same”, filed Jul. 31, 2002.
The present invention generally relates to a lamp module and a back light device having the lamp module, and more particularly, to a lamp module used in a direct type back light device.
It has been difficult to miniaturize the volume and the weight of conventional cathode ray tube (CRT) devices, and therefore liquid crystal display (LCD) devices characterized by compact size and excellent image qualities have gradually taken the place of CRT devices. Different from the CRT devices, the LCD device itself does not emit light. A back light source is required in an LCD device to emit lights.
Usually, the back light devices are generally classified into two types: an edge type and a direct type. The edge type back light device includes a lamp typically arranged on an edge side of the LCD device, a light guide plate disposed on a side surface of the lamp, a diffusion film disposed on top of the light guide plate, and a reflection plate disposed on bottom of the light guide plate. The light guide plate scatters rays irradiating from the lamp so that rays are uniformly incident into the diffusion film. The reflection plate reflects rays back to the diffusion plate so that most of the rays from the lamp are uniformly incident to the LCD panel by the diffusion plate.
Comparatively, the direct type back light device does not require a light guide plate. Linear light is directed to the display area from a light source via a diffusion plate and a reflection plate. Therefore, the direct type back light device is widely used in large sized LCD devices because it has high light transmission and does not have a limitation in the size of the display area.
In a conventional direct type back light device, each lamp is individually disposed on the frame or the reflection plate directly. These lamps are unable to be firmly positioned and secured, which results in leakage light or leakage currents, and more seriously, in damage of cables of power. Moreover, arranging the lamps directly on the frame complicates the disassembly procedure of the back light device when it needs repair. The replacement of individual lamp is generally performed in a clean room to reduce contaminations because of the complicated procedure. For example, when a lamp of the conventional back light device used in a LCD television needs to be replaced, the entire back light device has to be disassembled in a clean room, which makes on-site replacement impossible and delays the repair.
Therefore, there is a need to provide a back light module used in a back light device to simplify the assembly procedure and reduce the cost of assembly.
It is one aspect of the present invention to provide a lamp module and a back light device having the lamp module that reduces the cost of assembly and simplifies the assembly procedure by using a resilient holder to arrange a lamp tube on a support unit.
It is another aspect of the present invention to provide a lamp module for a back light device. The lamp module provides a support unit, which can dissipate heat and support different numbers of lamp tubes based on a variety of design needs.
It is a further aspect of the present invention to provide a lamp module for use with a back light device of a liquid crystal display apparatus. Several lamp tubes are assembled into a module. When certain lamp tubes need to be replaced, on-site replacement of the lamp module is performed without delay of the repair time caused by carrying the back light device to a clean room environment for changing lamp tubes.
In one embodiment of the present invention, a lamp module includes a resilient holder, a lamp tube, and a support unit. The resilient holder has an accommodation portion, such as a cavity, which is provided to accommodate one end of the lamp tube. The support unit has a reception portion, such as a groove, which is provided to engage with the resilient holder. The resilient holder further includes a plug portion, a first clamp portion and a second clamp portion. The plug portion is arranged between the first and second clamp portions, and used to engage with the reception portion of the support unit.
When the resilient holder engages with the support unit, the plug portion is constrained by the first and second clamp portions. The first clamp portion has a thickness larger than that of the plug portion. Further, a ditch is positioned on one side of the support unit in order to dissipate heat. The lamp module further includes a heat conductive element disposed in the ditch to dissipate heat.
The foregoing aspects and many of the attendant advantages of this invention will become more readily appreciated as the same becomes better understood by reference to the following detailed description, when taken in conjunction with the accompanying drawings, wherein:
The present invention discloses a lamp module for use with a back light device of a flat monitor. The lamp module is modulized to simplify the assembly process so as to reduce the cost of assembly.
As shown in
The shape and the size of the plug portion 122 are varied according to the reception portion 160 so that the plug portion 122 is closely in contact with the rim 164 of the reception portion 160. The reception portion 160 can be a groove 160. For example, the width W122 and a thickness T122 of the plug portion 122 are varied according to the width W160 and thickness T160 of the groove 160. When the width W122 and thickness T122 respectively and substantially equal to the width W160 and thickness T160, the plug portion 122 tightly engages with the groove 160. The first and second clamp portions 124 and 126 contacting the support unit 16 enhance the engagement, and therefore the plug portion 122 is restricted. Furthermore, the first clamp portion 124, which has a thickness T124 larger than the thickness T122 of the plug portion 122, provides a clamp force with respect to the stationary function provided by the second clamp portion 126. Moreover, to enhance the strength of the resilient holder 12, the thickness T124 of the first clamp portion 124 is preferably about 1.5 to 2 times larger than the thickness T122 of the plug portion 122.
The resilient holder 12 can be made of rubber or any materials as appropriate and made by, for example, an injection mold process. The resilient holder 12 further includes a channel 128 for allowing a cable (not shown) to pass through it and connects the lamp tube 14, and therefore the arrangement and connection of the cable are readily achieved. It is noted that though the resilient holder 12 is in a U shape in this embodiment, but it is not limited to this shape. The lamp tube 14 can be but not limit to, for example, a cold cathode fluorescent lamp (CCFL). The type and the shape of the lamp tube 14 are not limited to those of the exemplary embodiment.
As shown in
Although specific embodiments have been illustrated and described, it will be obvious to those skilled in the art that various modifications may be made without departing from what is intended to be limited solely by the appended claims.
Number | Date | Country | Kind |
---|---|---|---|
91117124 A | Jul 2002 | TW | national |
Number | Name | Date | Kind |
---|---|---|---|
RE30367 | Belokin, Jr. | Aug 1980 | E |
4773111 | Hyner et al. | Sep 1988 | A |
4949350 | Jewell et al. | Aug 1990 | A |
5031187 | Orenstein et al. | Jul 1991 | A |
5115442 | Lee et al. | May 1992 | A |
5138528 | Altman et al. | Aug 1992 | A |
5193098 | Welch et al. | Mar 1993 | A |
5219785 | Welch et al. | Jun 1993 | A |
5256596 | Ackley et al. | Oct 1993 | A |
5328854 | Vakhshoori et al. | Jul 1994 | A |
5371661 | Simpson | Dec 1994 | A |
5594751 | Scott | Jan 1997 | A |
5764674 | Hibbs-Brenner et al. | Jun 1998 | A |
5893722 | Hibbs-Brenner et al. | Apr 1999 | A |
6044100 | Hobson et al. | Mar 2000 | A |
RE36961 | Nagano | Nov 2000 | E |
6169756 | Chirovsky et al. | Jan 2001 | B1 |
6183107 | Donato | Feb 2001 | B1 |
Number | Date | Country |
---|---|---|
809845 | Apr 1996 | JP |
Number | Date | Country | |
---|---|---|---|
20040037073 A1 | Feb 2004 | US |