Patent Application
20050265022
1. Field of the Invention
This invention relates to a backlight module, and particularly to a backlight module that is easy to assemble, test and disassemble.
2. Description of the Prior Art
Generally, a backlight module refers to a device element capable of providing light source from the back of a product, which has being widely used in various products relative to information, communication and consumer goods, such as liquid crystal displays (LCD), film scanners, slide projectors and so on. The backlight module mainly includesinlcudes an incident light source, a light-guide plate, a diffusion sheet, a prism sheet and a brightness enhancement film (BEF). Put simply, its principle is that a self-luminous light from a light source, for example, a cold cathode fluorescent lamp (CCFL) and a light-emitting diode (LED), is conducted in by a light-guide plate to produce an even surface light source. Meanwhile, to keep the products competitive in future markets, the backlight module needs to take several product evolution directions into account: lighter weight, miniaturization, lower power consumption, higher brightness and lower cost.
Reference is made to
However, during assembling of the conventional backlight module 1a, a step of turning over the plastic frame 10a is required, and it is thus obvious that the assembly process is not smooth. Furthermore, the rigid frame 11a and the plastic frame 10a are arranged with a mutual securing engagement structure. After the rigid frame 11a is engaged and secured with the plastic frame 10a, it is to disassemble, which is a disadvantageous to the improvement of production efficiency. If there is any need for maintenance and repair or the the diffusion sheet 15a or the prism sheet 16a needs to be replaced, the rework process is cumbersome and the products are prone to damage; the structure is thus disadvantageous to the improvement of product yield. The above-mentioned product damage includes scoring and scratches on the diffusion sheet 15a, the prism sheet 16a, the light-guide plate 12a and the reflective sheet 14a, which adversly affect the overall brilliancy, thus reducing the value of the products. Moreover, depending on different design requirements, the number and the assembling sequence of the diffusion sheets 15a and the prism sheets 16a to be assembled may be not the same. In the event that a polarizing sheet, a intensifier sheet and other elements are added for purpose of adaptation of further optical characteristic, and it is desired to perform a test process to verify the elements are assembled in right sequence and registered properly, similar problems occur during the test process. Dissassembly of the engaged rigid frame 11a and plastic frame 10a is difficult, and the products are potentially damaged during disassembly and reassembly of the elements. Additionally, in the assembled structure of the conventional backlight module 1a, the stop sheet 101a is arranged on the optical films; thus the upward and even light output obtained from the effect of those optical films is subject to reduced light output area due to blocking by the stop sheet 101a. The conventional backlight module 1a is obviously unable to be made more cheaply.
Accordingly, this invention is provided to remove the above disadvantages with a reasonable design.
The main object of the invention is to provide a backlight module, which can reduce turnover steps, allowing the products to be easily and smoothly assembled and improves production efficiency to further reduce production costs.
An another object of the invention is to provide a backlight module, which allows convenient checking that the module is properly assembled. The the module is additionally easily repaired, further improving production efficiency and reducing production costs.
Yet another object of the invention is to provide a backlight module, which can avoid product damage during disassembly of the engaged rigid and plastic frames and eliminate defects to reduce further scrap possibility and production costs.
Yet another object of the invention is to provide a backlight module, which can increase a light output area, to achieve efficient utilization of the backlight module, thus further reducing production costs.
In order to achieve the above object, the present invention provides a backlight module, consisting of mutually engaged rigid and plastic frames, of which the plastic frame is arranged at its top with a stop sheet protruding inward along the inner perimeter, a light-guide plate and a light-emitting element arranged between the rigid and plastic frames, and a group of optical elements arranged on the stop sheet. The module is further coupled with a glass substrate positioned on the group of optical elements, thereby allowing the products to be easily and smoothly assembled. The group of optical elements can be conveniently checked and the rigid and plastic frames are easily disassembled from each other.
The features and technical contents of the present invention will become apparent from the detailed description of the present invention with reference to the accompanying drawings; the detailed description and drawings are intended to be illustrative and not restrictive.
The foregoing aspects and many of the attendant advantages of this invention will be 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 backlight module according to the invention is assembled in the following steps. The reflective element 14, the light-guide 12 and the light-emitting element 13 are directly received into the receiving space of the rigid frame 11. The plastic frame 10 is the inserted to be jacketed and engaged with the rigid frame 11, so as to sandwich the light-guide plate 12 and light-emitting element 13 in between. The need of a turnover step for the plastic frame 10 is eliminated, thereby facilitating the easy and smooth assembly of the module, and thus further speeding production flow and improving production efficiency. Additionally, according a specific design requirement, the group of optical elements 15 are arranged above the stop sheet 101, such that the group of optical elements 15 and the light-guide plate 12 form a relationship in which they are positioned at opposite sides of the stop sheet 101. In particular, a side light source emitted from the light-emitting element 13 is converted into a surface light source through the light-guide plate 12. After the light source passes through the stop sheet 101, benefiting from the optical effect of the diffusion sheet or the prism sheet in the group of optical elements 15, the projection of the surface light source is not affected by the limit of the stop sheet 101, thereby increasing the area of the light output and achieving the efficient utilization of the backlight module 1.
During situation such as, for example, examination, maintenance or material replacement during the production process, the backlight module 1 according to this invention can easily be examined and the constitution and configuration of the group of optical elements 15 changed and replaced, without dissassembling the plastic frame 10 from the rigid frame 11, thereby improving assembling the quality of the backlight module 1 and the entire production efficiency. In addition, without dissassembling the mutually engaged rigid frame 11 and plastic frame 10, the risk of unnecessary damage to the products, such as scratches resulting in uneven overall brilliance can be avoided, thereby reducing the manufacturing cost.
With respect to the backlight module industry, material costs are a significant portion of the total cost of a backlight module, and some key materials are mainly sourced from only a few Japanese and US manufacturers; the profit margins of backlight module manufacturers therefore rests on assembling charge and other expenses. From the view point of the manufacturing process, a backlight module can be considered to be a labor-intensive assembly industry with high management requirements. Therefore, the backlight module 1 according to the invention features advantages of being easy to assemble and examine and being convenient to maintaine. This not only improves the smoothness of the production flow, but also effectively reduces examination and scrap costs; furthermore the efficient utilization of the light output area is improved. The backlight module 1 according to this invention has a great advantage in keeping competitive in the era of profit squeezing. In conclusion, the desired objects and functions are achieved in this invention; while the techniques and means have been disclosed above merely as one of the preferred embodiments of this invention. It is intended that the appended claims cover all such modifications and variations made to these embodiments as fall within the spirit and scope of this present invention.
