KR20090055410A - Liquid crystal display device - Google Patents

Abstract

An LCD is provided to fasten an FPCB with a lower cover easily by attaching a fixed tape after fastening the FPCB with a fixing groove formed in the rear of the lower cover. An LCD(Liquid Crystal Display) comprises an LC panel, a light source, a lower cover(103), an exposure hole(103a), an optical sensor(105), an FPCB(Flexible Printed Circuit Board)(106), a fixing groove(103b), and a fixed tape(107). The light source supplies light to the LC panel. The lower cover receives the LC panel and the light source. The exposure hole is formed in a lower part of the lower cover. The optical sensor is arranged in order to be corresponded to the exposure hole. The FPCB is arranged in a rear side of the lower cover. The FPCB includes a first area, where the optical sensor is mounted, and a second area having a width narrower than a width of the first area. The fixing groove is formed in the rear side of the lower cover, and fastened with a part of the FPCB. The fixed tape is adhered to a rear side of the FPCB.

Description

Liquid crystal display {LIQUID CRYSTAL DISPLAY DEVICE}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal display, and in particular, a liquid crystal having a light brightness control module including an optical sensor for detecting the brightness of light emitted from a light source and a brightness control unit for controlling the brightness using brightness data of light received from the light sensor. The present invention relates to a liquid crystal display device in which a flexible printed circuit board on which the optical sensor is mounted is fastened to a lower cover, and at the same time, a movement of the flexible printed circuit board is prevented.

BACKGROUND ART In general, liquid crystal display devices have tended to be gradually widened due to their light weight, thinness, and low power consumption. Accordingly, the liquid crystal display device is widely used as a portable computer such as a notebook PC, office automation equipment, audio / video equipment, and the like.

In general, a liquid crystal display device displays a desired image on a screen by adjusting the amount of light transmitted according to image signals applied to a plurality of control switching elements arranged in a matrix.

The liquid crystal display device is a liquid crystal in which a color filter substrate as an upper substrate and a thin film transistor array substrate as a lower substrate face each other and a liquid crystal layer is filled between the two substrates. And a driving unit for supplying scan signals and image information to the liquid crystal panel to operate the liquid crystal panel.

The liquid crystal display having the above configuration is a non-light emitting device which does not emit light by itself compared to a cathode-ray tube (CRT) or a light emitting diode (LED). There is a need for a backlight assembly that provides light to the panel.

Light sources generating light in the backlight assembly include a cold cathode fluorescent lamp (CCFL), an external electrode fluorescent lamp (EEFL), and an LED.

Conventionally, a cold cathode fluorescent lamp is mainly used as a light source of a backlight assembly. However, recently, a liquid crystal display device adopting an LED, which is advantageous in power consumption, weight, and luminance, as a light source of a backlight assembly is being used in accordance with the trend toward miniaturization, thinness, and light weight of a liquid crystal display device. Growing.

In the backlight assembly having the LED as a light source as described above, red, green, and blue (hereinafter, R, G, B) LEDs are alternately arranged, and light of R, G, B emitted from the R, G, B LEDs. Silver has a characteristic of being supplied to the liquid crystal panel after being converted into uniform white light by mixing.

However, the LED as described above has a problem that the characteristics of the emitted light changes over time. In particular, the LED generates a lot of heat during the driving process, there is a problem that the brightness is lowered by this heat, and the uniform white light desired because the degree of the brightness of the light emitted by each of the R, G, B LEDs is different. There has been a problem that can not be obtained.

Accordingly, in order to solve the above problem, in a liquid crystal display device in which the LED is provided as a light source, an optical sensor for detecting the luminance of light emitted from the LED and power supplied to the LED using the luminance data received from the optical sensor are used. A liquid crystal display device having a light brightness control module including a light brightness control unit for controlling brightness by adjusting the brightness has been proposed.

Hereinafter, a conventional liquid crystal display device will be described with reference to the accompanying drawings.

As shown in FIG. 1, a conventional liquid crystal display device includes a liquid crystal panel 1, an LED (not shown) for supplying light to the liquid crystal panel 1, and light emitted from the LED. 1) the light guide plate 8 guiding in the direction, the optical sheet 9 for converting the light emitted from the light guide plate 8 to the liquid crystal panel 1, and the light exposed under the light guide plate 8; A reflector 10 for reflecting the light toward the liquid crystal panel 1, a lower cover 3 for accommodating the liquid crystal panel 1, an LED, a light guide plate 8, an optical sheet 9 and a reflector 10, The upper cover 11 is coupled to the lower cover 3 and surrounds the edge of the upper surface of the liquid crystal panel 1.

In addition, an optical sensor 5 corresponds to one side of the lower portion of the lower cover 3 to form a hole 3a for directing the optical sensor to the inside of the lower cover 3, and around the hole 3a. A plurality of fastening protrusions 3b protruding downward from the rear surface of the lower cover 3 are formed.

In addition, a flexible printed circuit board (FPCB) 6 having the optical sensor 5 mounted thereon is formed on a rear surface of the lower cover 3, wherein the flexible printed circuit board 6 has the lower portion. A fastening hole 6a is formed to correspond to the fastening protrusion 3b formed on the rear surface of the cover 3.

A fixing tape 7 is attached to the rear surface of the flexible printed circuit board 6.

Although not shown, a liquid crystal panel driver (not shown) for driving the liquid crystal panel 1 is disposed outside the lower cover 3, and the luminance data received from the optical sensor 5 is disposed in the liquid crystal panel driver. Light control unit (not shown) for controlling the brightness by adjusting the power supplied to the LED is formed together. Here, the optical sensor 5 and the brightness control unit forms a brightness control module.

1 and 2, the flexible printed circuit board 6 on which the optical sensor 5 is mounted has a plurality of fastening protrusions 3b and flexible printed circuit boards formed on the lower cover 3 during the fastening process. 6) After aligning the plurality of fastening holes 6a formed in the fastening hole 6a and the fastening protrusions 3b by a pair, a fixing tape is formed on the rear surface of the flexible printed circuit board 6. 7) is attached to the lower cover (3).

However, in the liquid crystal display device as described above, the process of fastening the fastening hole 6a and the fastening protrusion 3b of a very small size is not easy, and the flexible printing is performed by fastening the fastening hole 6a and the fastening protrusion 3b. Since the position of the circuit board 6 is determined, the flexible printed circuit board 6 may cry in the process of attaching the fixing tape 7, thereby causing a problem of wrinkles.

Accordingly, the present invention is to solve the above problems, an object of the present invention is to facilitate the operation of fastening the flexible printed circuit board mounted with the optical sensor to the lower cover and at the same time prevent the undulation of the flexible printed circuit board. It is to provide a liquid crystal display device having a.

Liquid crystal display device according to an embodiment of the present invention for achieving the above object, the liquid crystal panel; A light source for supplying light to the liquid crystal panel; A lower cover accommodating the liquid crystal panel and the light source; At least one exposure hole formed in a lower portion of the lower cover; An optical sensor disposed to correspond to the exposure hole; A flexible printed circuit board disposed on a rear surface of the lower cover and including a first region in which the optical sensor is mounted and a second region having a width W2 narrower than the width W1 of the first region; A fixing groove formed on a rear surface of the lower cover, to which a part of the flexible printed circuit board is fastened; A fixing tape attached to a rear surface of the flexible printed circuit board; It is configured to include.

In the liquid crystal display according to the present invention having the configuration described above, the flexible printed circuit board on which the optical sensor is mounted is fastened to the fixing groove formed on the bottom of the lower cover and the flexible tape is adhered to the back of the flexible printed circuit board. Since the operation of fastening the circuit board to the lower cover is simply completed, there is an advantage that the fastening operation of the flexible printed circuit board and the lower cover is easy.

In addition, in the process of fastening the flexible printed circuit board to the lower cover, the side of the entire first area of the flexible printed circuit board and the side of the portion of the second area contact the surface forming the fixing groove of the lower cover. Since the correct alignment of the cover is made, the shape of the flexible printed circuit board is preserved in the process of attaching the fixing tape to the rear surface of the flexible printed circuit board, so that no phenomenon occurs.

In addition, the flexible printed circuit board has a width W1 of the first area larger than the width W2 of the second area. Therefore, when the flexible printed circuit board is disposed in the fixing groove, the top and bottom sides of the flexible printed circuit board are formed. When the X and Y axes are formed, the positive and negative directions of the X axis and the positive and negative directions of the Y axis are fixed to prevent alignment and flow. In the process of attaching the fixing tape, the shape of the flexible printed circuit board is preserved, which does not occur.

And formed in a portion of the region corresponding to the second region of the flexible printed circuit board, and starting from the region corresponding to the boundary between the first region and the second region of the flexible printed circuit board and moving away from the region corresponding to the first region. By the inclined portion of the fixing groove of the lower cover formed to increase gradually, there is an advantage that the phenomenon that the boundary between the first region and the second region of the flexible printed circuit board is lifted.

Hereinafter, a liquid crystal display according to an exemplary embodiment of the present invention will be described in detail with reference to the accompanying drawings.

3 and 4, the liquid crystal display according to the preferred embodiment of the present invention, the liquid crystal panel 101; A light source (not shown) for supplying light to the liquid crystal panel 101; A lower cover 103 for receiving the liquid crystal panel 101 and the light source; At least one exposure hole 103a formed under the lower cover 103; An optical sensor 105 disposed to correspond to the exposure hole 103a; A second area disposed on a rear surface of the lower cover 103 and having a width W2 narrower than a width W1 of the first area A on which the optical sensor 105 is mounted and the first area A; A flexible printed circuit board 106 comprising a region B; A fixing groove 103b formed on a rear surface of the lower cover 103 to which a part of the flexible printed circuit board 106 is fastened; A fixing tape 107 attached to a rear surface of the flexible printed circuit board 106; It is configured to include.

In addition, the fixing groove 103b of the lower cover 103 is formed to correspond to the second area B of the flexible printed circuit board 106, and the first region A and the first region of the flexible printed circuit board 106 are formed. An inclined portion C is formed so as to increase from the region corresponding to the boundary of the two regions B and gradually increase away from the region corresponding to the first region A. FIG.

Each component of the liquid crystal display according to the preferred embodiment of the present invention having the above configuration will be described in detail as follows.

As shown in FIG. 3, the liquid crystal panel 101 includes a color filter substrate 101a as an upper substrate and a thin film transistor array substrate 101b as a lower substrate, and a liquid crystal layer (not shown) between the two substrates. Is formed.

A light source is disposed below the liquid crystal panel 101, and the liquid crystal panel 101 receives light from the light source to display a screen.

Although not shown in detail in the drawings, the light source provided in the liquid crystal display according to the present invention is an example of a light emitting diode (LED) formed on one side of a lower region of the liquid crystal panel. The light source is not limited thereto, and various examples are possible, such as being configured with LEDs formed on the entire lower region of the liquid crystal panel 101.

Referring to FIG. 3, a light guide plate 108 for guiding light emitted from the light source toward the liquid crystal panel 101 is provided. Although not shown in detail in the drawing, the light guide plate 108 is formed with a light incident surface on which light emitted from a light source is incident and a light exit surface at a position opposite to the light incident surface.

In addition, a lower portion of the light guide plate 108 is provided with a reflective sheet 110 for reflecting light leaking into the lower portion of the light guide plate 108 into the light guide plate, and the upper portion of the light guide plate 108 is emitted from the light guide plate 108. An optical sheet 109 for converting light and supplying the light to the liquid crystal panel 101 is provided.

Referring to FIG. 3, a liquid crystal display according to an exemplary embodiment of the present invention includes a lower portion for accommodating a light source, a light guide plate 108, a reflective sheet 110, and an optical sheet 109 in addition to the liquid crystal panel 101. A cover 103 is provided, and an outer cover 111 is coupled to the lower cover 103 to surround the upper edge of the upper surface of the liquid crystal panel 101.

The lower cover 103 has an exposure hole 103a formed at a position corresponding to the optical sensor 105, and a plurality of exposure holes 103a may be provided according to the number of the optical sensors 105.

In addition, the lower cover 103 is formed with a fixing groove 103b to which a part of the flexible printed circuit board 106 is fastened, which will be described in detail with the description of the flexible printed circuit board 106 below. Do it.

As shown in FIG. 3, the optical sensor 105 disposed to correspond to the exposure hole 103a of the lower cover 103 may have a brightness along with a brightness control unit (not shown) provided outside the lower cover 103. A control module is achieved.

The brightness control module detects the brightness of red, green, and blue (hereinafter, R, G, and B) light emitted from the light source, that is, the LED, through the optical sensor 105, and then transmits the brightness data to the brightness control unit. By controlling the power supplied to the LED by controlling the transmission, the brightness of the R, G, B light is controlled so that the R, G, B light can be mixed and become white light.

Although not shown in detail in the drawings, the outside of the lower cover 103 is provided with a light source driver (not shown) for supplying power to the light source and a liquid crystal panel driver (not shown) for driving the liquid crystal panel 101. In the liquid crystal display according to the preferred embodiment of the present invention, the light source driver and the brightness controller are formed together in the liquid crystal panel driver. Of course, the liquid crystal panel driver, the light source driver and the brightness controller may be separately formed and separately disposed.

The optical sensor 105 as described above is mounted on a flexible printed circuit board (FPCB) 106 to be electrically connected to the light intensity controller through a circuit in the flexible printed circuit board 106. The brightness sensor 100 detects the luminance data detected by the optical sensor 105.

3 and 4, the flexible printed circuit board 106 is disposed on the rear surface of the lower cover 103, and includes a first region A and a first region on which the optical sensor 105 is mounted. It consists of the 2nd area | region B which has width W2 narrower than width W1 of A). In this case, connection means such as a connector (not shown) connected to the brightness control unit may be formed in the second region B.

A part of the flexible printed circuit board 106 is fastened to a fixing groove 103b provided on the rear surface of the lower cover 103, which will be described in detail below.

3 and 4, the fixing groove 103b of the lower cover 103 corresponds to the entire first area A of the flexible printed circuit board 106 and at the same time the first area A of the second area B. As shown in FIG. It is formed to correspond to an area connected to the area A, and is formed in a shape that is recessed inward from the rear surface of the lower cover 103, that is, an intaglio shape. In FIG. 5A, only the exposure hole 103a and the fixing groove 103b of the lower cover 103 are shown in detail. Referring to this, the fixing groove 103b of the lower cover 103 is a flexible printed circuit board 106. It can be seen that it is formed to correspond to the entirety of the first region A and the portion of the second region B, that is, to have the same shape.

As shown in FIG. 5B, the fixing groove 103b of the lower cover 103 is formed in a shape corresponding to the entirety of the first region A and the portion of the second region B of the flexible printed circuit board 106. When the flexible printed circuit board 106 is fastened therein, the flexible printed circuit board 106 including the first area A and the second area B having different widths W1 and W2 from each other in the vertical, vertical, horizontal directions. It is fixed securely and flow is prevented. Here, the up, down, left and right directions, when the plane forming the back surface of the lower cover 103 forms the X-axis and the Y-axis as shown in Figure 5b and the positive direction of the X-axis and the positive direction of the Y-axis It is in the negative direction.

In addition, the flexible printed circuit board 106 has a side thereof fixed in contact with a surface forming the fixing groove 103b of the lower cover 103 so that the contact area for fixing is wide, and is formed on the rear surface of the printed circuit board 106. When the fixing tape 107 is attached, the flexible printed circuit board 106 is preserved in the fixing groove 103b of the lower cover, thereby minimizing the occurrence of wrinkles due to the movement of the flexible printed circuit board 106. do.

3, 4, and 5C, the fixing tape 107 is attached to the entire first area A and a part of the second area B of the flexible printed circuit board 106 as an example. It is not limited to this, and the attachment range of the fixing tape 107 may be various examples within the scope not departing from the gist of the present invention.

The vertical thickness of the space formed by the fixing groove 103b is equal to the vertical thickness of the flexible printed circuit board 106 or is greater than the thickness of the flexible printed circuit board 106.

That is, in FIG. 3, the upper and lower thicknesses of the space formed by the fixing grooves 103b are the same as the upper and lower thicknesses of the flexible printed circuit board 106, but the upper and lower thicknesses of the space formed by the fixing grooves 103b are Various examples are possible without departing from the spirit of the invention.

Incidentally, an inclined portion C is formed in a part of the fixing groove 103b corresponding to the second region B of the flexible printed circuit board 106, and the inclined portion C is a flexible printed circuit. It is formed so as to increase from the region corresponding to the boundary between the first region A and the second region B of the substrate 106 and further away from the region corresponding to the first region A. FIG.

When the flexible printed circuit board 106 is fastened to the fixing groove 103b having the inclined portion C as described above, the second region B protrudes from the lower direction (see FIG. 3) of the rear surface of the lower cover 103. Some of the regions disposed in the inclined portion C of the fixing groove 103b of the second region B have the same inclination as the inclined portion C of the fixing groove 103b.

Therefore, part of the second region B of the flexible printed circuit board 106 is disposed inside the inclined portion C, so that the floating region of the boundary region between the first region A and the second region B is raised. This is avoided.

1 is a cross-sectional view showing a conventional general liquid crystal display device.

FIG. 2 is a plan view illustrating the liquid crystal display of FIG. 2 as viewed from the back; FIG.

3 is a cross-sectional view showing a liquid crystal display device according to a preferred embodiment of the present invention.

FIG. 4 is a plan view illustrating the liquid crystal display of FIG. 3 viewed from the back; FIG.

5A to 5C are views illustrating a liquid crystal display device viewed from the back, and a perspective view for explaining in detail the configuration and fastening of the lower cover and the flexible printed circuit board.

** Description of the symbols for the main parts of the drawings **

101: liquid crystal panel 103: lower cover

103a: exposure hole 103b: fixing groove

105: optical sensor 106: flexible printed circuit board

107: fixed tape

Claims (7)

A liquid crystal panel; A light source for supplying light to the liquid crystal panel; A lower cover accommodating the liquid crystal panel and the light source; At least one exposure hole formed in a lower portion of the lower cover; An optical sensor disposed to correspond to the exposure hole; A flexible printed circuit board disposed on a rear surface of the lower cover and including a first region in which the optical sensor is mounted and a second region having a width W2 narrower than the width W1 of the first region; A fixing groove formed on a rear surface of the lower cover, to which a part of the flexible printed circuit board is fastened; A fixing tape attached to a rear surface of the flexible printed circuit board; Liquid crystal display device comprising a. The liquid crystal display of claim 1, wherein an inclined portion is formed in a part of the fixing groove. The method of claim 2, wherein the inclined portion is formed in a region corresponding to the second region of the flexible printed circuit board, And wherein the inclined portion starts at an area corresponding to a boundary between the first area and the second area of the flexible printed circuit board and gradually increases as the distance from the area corresponding to the first area increases. The liquid crystal display device according to claim 1, wherein the vertical thickness of the space formed by the fixing groove is equal to the vertical thickness of the flexible printed circuit board or larger than the thickness of the flexible printed circuit board. The liquid crystal display of claim 1, wherein the light source is a light emitting diode, and the optical sensor detects a brightness of the light source. The liquid crystal display of claim 5, wherein an external light control unit is further provided outside the lower cover to control the brightness of the light source by using the brightness of the light emitted from the light sensor. The liquid crystal display of claim 1, wherein an additional liquid crystal panel driver is disposed outside the lower cover to control driving of the liquid crystal panel, and the light luminance controller is formed in the liquid crystal panel driver.

Images