LCD assembly with reduced thickness and method for assembling the same

Abstract: An LCD (Liquid Crystal Display) assembly with reduced thickness to be suitable for a communication terminal using an LCD as a display unit and a method for assembling the same. The LCD assembly comprises an LCD, an LCD driver for driving said LCD and a PCB (Printed Circuit Board). To reduce the thickness of the assembly, said LCD driver is at least partly located in a recess formed in said PCB.

Description: The present invention relates to a liquid crystal display (LCD) for use in a communication terminal, and in particular, to an LCD assembly with reduced thickness to be suitable for a communication terminal and a method for assembling the same. In general, an LCD is widely used for a display unit of a communication terminal such as a cordless portable telephone. Such an LCD is constructed in the form of a module, and installed in a PCB (Printed Circuit Board) of the communication terminal to display various operating status of the communication terminal. FIG. 1A illustrates a known LCD assembly in which an LCD is installed in a PCB of a portable telephone. Referring to FIG. 1A, an LCD 10 is installed in a PCB 30 using a flexible cable 20 for electrically connecting the LCD 10 to the PCB 30. The flexible cable 20 has an LCD driver 40 disposed at the center surface thereof, as shown in FIG: 1B. In general, the LCD driver 40 for driving the LCD 10 is realised by a TAB IC (Tape Automated Bonding Integrated Circuit). FIG: 2 is an assembling diagram showing how the LCD 10 is installed in the PCB 30 according to the prior art. Referring to FIG. 2, the LCD 10 is installed in the PCB 30 and electrically connected to the PCB 30 through the flexible cable 20. Likewise, the flexible cable 20 has the LCD driver 40 disposed at the center surface thereof, facing to the backside of the LCD 10. The reason that the flexible cable 20 is used in connecting the LCD 10 to the PCB 30 is because the flexible cable 20 is freely bendable toward the backside of the LCD 10, thereby reducing the thickness of the LCD Assembly. Here, it is noted that the LCD driver 40 is disposed at a center surface of the flexible cable 20, facing to the backside of the LCD 10. Accordingly, in installing the LCD 10 in the PCB 30, the LCD assembly needs a width d2 of the LCD driver 40 plus an extra space d1 between the LCD driver 40 and the LCD 10, needed in some applications to secure a space between LCD and PCB. In practice, in order to offer the extra space d1, guides (not shown) are attached to a side where the LCD 10 is connected to the flexible cable 20 and its opposite side, i.e., to both ends of the LCD 10. To sum up, the conventional LCD assembly needs at least the width d2 of the LCD driver 40 to install the LCD 10 in the PCB 30, so that the communication terminal having the LCD assembly becomes undesirably thick. European Patent No. 0 776 038 A2 discloses an LCD assembly where the LCD driver is mounted in a hollow portion or a through hole of the PCB. However, a hollow portion or through hole of the PCB in Figure 2 does not allow for the desired reduction of the overall assembly thickness, since the driver is facing towards the LCD. It is therefore an object of the present invention to provide an LCD assembly using a flexible cable connecting the LCD to the PCB with reduced thickness to be suitable for a communication terminal using an LCD as a display unit, and a method for assembling the same. To achieve the above object, there is provided an inventive method comprising the features of claim 1 and LCD assembly comprising the features of claim 3. Preferable embodiments are a subject matter of the dependent claims. This measure provides a significantly reduced thickness of the LCD assembly, since the LCD driver is at least partly located within the recess. The above object and advantages of the present invention will become more apparent by describing in detail preferred embodiments thereof with reference to the attached drawings in which: FIG. 1A is a diagram illustrating a known LCD assembly in which an LCD is installed in a PCB; FIG. 1B is a top view illustrating a flexible cable (/20) of FIG. 1A, having an LCD driver (40) at a center surface thereof; FIG. 2 is an assembling diagram showing how to install the LCD in the PCB according to the prior art; FIG. 3A is an assembling diagram showing how to install an LCD in a PCB according to an embodiment of the present invention; and FIG. 3B is a diagram illustrating an LCD assembly in which the LCD is installed in the PCB according to the embodiment of the present invention. A Preferred embodiment of the present invention will be described in detail referring to the attached drawings, in which the like reference numerals denote the same elements in the drawings, for understanding. Though the specific embodiment will be exemplarily defined and described in detail to clarify the subject matter of the present invention, the present invention may be implemented with the description of the present invention by those skilled in the art even without the details. In addition, an unnecessary detailed description of widely known functions and constructions may be avoided here. FIG. 3A illustrates how to install the LCD 10 in the PCB 30 according to an embodiment of the present invention, and FIG. 3B illustrates an LCD assembly according to the present invention. As mentioned above, this LCD assembly can be used for a communication terminal such as a portable telephone. Referring to FIG. 3A, the flexible cable 20 is interposed between the backside of the LCD 10 and the front side of the PCB 30, being bent inward at an end portion connected to the LCD 10, and electrically connects the LCD 10 to the PCB 30. The LCD driver 40 for driving the LCD 10 is disposed at a specific place, preferably, at the center surface of flexible cable 20, facing to the front side of the PCB 30. For example, a TAB IC 6F-F02 manufactured by Samsung Electronics Co. can be used for the LCD driver 40. The PCB 30 has a through hole formed at a position corresponding to where the LCD driver 40 is disposed. The LCD driver 40 is inserted into the through hole formed in the PCB 30, so that the thickness of the LCD assembly may be minimised. In practice, a large-sized element such as an LSI (Large Scale IC) chip can be disposed at the opposite side of the PCB 30, covering the through hole. In this case, there is no limitation in utilising the surfaces of the PCB 30. The LCD assembly does not need the extra space d1 between the LCD 10 and the LCD 40. That is, the LCD assembly according to the present invention can reduce the extra space d1 which was needed in the conventional LCD assembly, by disposing the LCD driver 40 at the opposite side of the flexible cable 20. FIG. 3B illustrates the LCD assembly in which the LCD 10 is installed in the PCB 30 according to the embodiment of the present invention. As illustrated, the LCD driver 40 is inserted into the through hole formed in the PCB 30, thereby minimising the thickness of the LCD assembly. Actually, when assembled, the LCD assembly according to the present invention has the thickness of the LCD 10 plus the thickness of the PCB 30, thus reducing the extra space d1. On the contrary, however, the conventional LCD assembly has (the thickness of the LCD 10) + (the thickness of the PCB 30) + (the thickness d2 of the LCD driver 40 ) + (the extra space d1). For example, in the ordinary portable telephone, the thickness of the LCD driver 40 is about 0.4 mm, and the extra space d1 is about 0.6 - 0.8 mm. Accordingly, if the LCD assembly according to the present invention is applied to the portable telephone, the thickness of the portable telephone can be reduced by 1.0 -1.2 mm. As described above, by changing a position where the LCD driver is disposed and inserting the LCD driver into the through hole formed at the corresponding place where the LCD driver is disposed, the thickness of the LCD assembly can be reduced by 1.0 - 1.2 mm in maximum. Therefore, it is possible to reduce the thickness of the portable telephone, thereby offering a great convenience to the user. Although illustrative embodiments of the present invention have been described herein with reference to the accompanying drawings, it is to be understood that the invention is not limited to those precise embodiments, and that various other changes and modifications may be affected therein by one skilled in the art without departing from the scope of the invention.

Claims: Method for installing an LCD (Liquid Crystal Display) (10) and an LCD driver (40) for driving said LCD in a PCB (Printed Circuit Board) (30), comprising the steps of: using a flexible cable (20) for electrically connecting the LCD (10) to the PCB (30); disposing said LCD driver (40) for driving said LCD (10) at a specific place on said flexible cable (20), causing the LCD driver (40) to face to said PCB (30); forming a recess in the PCB (30) at a position corresponding to where said LCD driver (40) is disposed; and inserting said LCD driver (40) at least partly into said recess. Method as defined in claim 1, characterized in that said recess is formed as a through hole in the PCB. LCD assembly comprising: an LCD (Liquid Crystal Display) (10), an LCD driver (40) for driving said LCD, and a PCB (Printed Circuit Board) (30), wherein said LCD driver (40) is at least partly located in a recess formed in said PCB (30), characterized in that said LCD driver (40) is disposed at a specific place on a flexible cable (20) that is used to electrically connect the LCD (10) to the PCB (30), facing to the front side of the PCB (30). LCD assembly as claimed in claim 3, characterized in that said recess is formed as a through hole in said PCB (30). LCD assembly as claimed in claim 3 or 4, characterized in that said flexible cable is interposed between a backside of said LCD (10) and the front side of said PCB (30) and being bent inward at an end portion connected to said LCD (10). LCD assembly as claimed in any of the claims 3 to 5, characterized in that said LCD driver (40) is disposed at a center surface of the flexible cable (20).

Inventors: JUNG JAE-IK, JUNG, JAE-IK, Jung, Jae-Ik c/o SAMSUNG ELECTRONICS CO., LTD.
Applicants: SAMSUNG ELECTRONICS CO LTD, SAMSUNG ELECTRONICS CO., LTD.
Application year: 1998
Main classification: H05K1
IPC codes: H05K1, G02F1, H05K13