KR20080041351A - Liquid crystal display - Google Patents

Abstract

An LCD device is provided to measure the intensity of external radiation more finely by an optical sensor and a light leading unit, thereby reducing the power consumption of a backlight assembly which takes up a considerable part of power consumption used in the LCD device. An LCD(Liquid Crystal Display) panel displays an image. A backlight assembly supplies light to the LCD panel. An inverter supplies power to the backlight assembly. An inverter is formed in an inverter substrate(20). An optical sensor(25) is formed in the inverter substrate to control the intensity of radiation in the backlight assembly according to the intensity of external radiation. A container protects and contains the LCD panel and the backlight assembly. An opening portion(7) is formed in the container and is formed in a position corresponding to the optical sensor. A light leading unit(9) is formed in the opening portion and transfers external light to the optical sensor.

Description

Liquid crystal display {LIQUID CRYSTAL DISPLAY}

1 is an exploded perspective view illustrating a liquid crystal display according to a first embodiment of the present invention.

FIG. 2 is a cross-sectional view illustrating the inverter substrate taken along the line II ′ in FIG. 1.

FIG. 3 is a plan view illustrating the LCD device excluding the front case of FIG. 1.

4 is a cross-sectional view illustrating the inverter substrate and the front case taken along the line II-II ′ in FIG. 1.

5 is a cross-sectional view illustrating the inverter substrate and the front case according to the second embodiment of the present invention.

<Short description of drawing symbols>

5: front case 7: opening

9: mineral induction part 10: top chassis

15: accommodating part 20: inverter board

23: hole 25: light sensor

40 liquid crystal display panel 41 color filter substrate

43: thin film transistor substrate 53: gate driver integrated circuit

57: data driver integrated circuit 60: mold frame

70: backlight assembly 79: optical sheet

81: lamp unit 83: light guide plate

85: reflective sheet 90: bottom chassis

150: liquid crystal display device

The present invention relates to a liquid crystal display, and more particularly, to a liquid crystal display capable of reducing power consumption of a backlight assembly.

In general, as the modern society becomes information socialized, the importance of one liquid crystal display (LCD) of an information display device is gradually increasing. The most widely used Cathode Ray Tube (CRT) has many advantages in terms of performance and price, but has many disadvantages in terms of miniaturization or portability. On the other hand, the liquid crystal display device is somewhat expensive in terms of price, but its application range is gradually widening due to features such as miniaturization, light weight, thinness, and low power consumption. Such a liquid crystal display device displays a desired image by applying an electric field to a liquid crystal material having an anisotropic dielectric constant injected between two substrates, and controlling the amount of light transmitted through the substrate by adjusting the intensity of the electric field.

As described above, the liquid crystal display device includes a liquid crystal display panel for displaying an image largely, a driving circuit unit for driving the liquid crystal display panel, a backlight assembly for providing light to the liquid crystal display panel, a front case for storing and fixing them, a top chassis, Contains the bottom chassis.

The backlight assembly includes a lamp unit for generating light, a light guide plate for guiding light generated by the lamp unit in the direction of the liquid crystal display panel, a reflective sheet for increasing the efficiency of light, and various optical sheets. In addition, an inverter for supplying power to the lamp unit is provided. Such an inverter is formed on an inverter printed circuit board. The inverter converts a DC input voltage into an AC voltage and outputs the AC voltage. Such a backlight assembly occupies a considerable portion of the power consumed in the liquid crystal display. However, since liquid crystal displays such as mobile phones and laptops are portable, reducing power consumption facilitates long-term portability and mobility. Therefore, in order to reduce power consumption of the backlight assembly, a method of forming an optical sensor for sensing an external light amount on an inverter printed circuit board and controlling the lamp using the same has been studied.

However, in the related art, the amount of light that the optical sensor can accept when external light is incident is limited. It is reflected on the printed circuit board of the front case or inverter when light is incident, so that all external light is not incident to the optical sensor. Accordingly, there is a problem that can not measure the exact amount of light can not obtain a great effect in reducing the power consumption.

Accordingly, an aspect of the present invention is to provide a liquid crystal display device having a light guide part, which can reduce power consumption of a backlight assembly.

In order to achieve the above technical problem, a liquid crystal display device according to the present invention includes a liquid crystal display panel for displaying an image, a backlight assembly for supplying light to the liquid crystal display panel, an inverter for supplying power to the backlight assembly, An inverter substrate on which an inverter is formed, an optical sensor formed on the inverter substrate to adjust an amount of light of the backlight assembly according to an external light amount, an accommodating portion protecting and accommodating the liquid crystal display panel and the backlight assembly, and the accommodating portion And an opening formed at a position corresponding to the optical sensor, and a light induction unit formed in the opening to transmit external light to the optical sensor.

The light guide part is formed of a convex lens that collects external light.

The optical sensor may be formed under the inverter substrate.

In addition, the inverter substrate is characterized in that to form a hole in a position corresponding to the optical sensor.

The accommodating part includes a top chassis formed above the liquid crystal display panel, a bottom chassis formed under the liquid crystal display panel, and a front case formed on the top chassis to accommodate the liquid crystal display panel and the backlight assembly. It is characterized by.

This, characterized in that it comprises a receiving portion for receiving the inverter and the inverter substrate on one side of the top chassis.

On the other hand, the opening is characterized in that formed in the front case.

In order to achieve the above technical problem, a liquid crystal display device according to the present invention is a liquid crystal display panel for displaying an image, a backlight assembly for supplying light to the liquid crystal display panel, and protects and accommodates the liquid crystal display panel and the backlight assembly An accommodating part, an inverter for supplying power to the backlight assembly, an inverter substrate on which the inverter is formed, an optical sensor formed under the inverter substrate, and controlling the power according to an external light amount, And a hole formed at a position corresponding to the optical sensor, and a light induction part formed in the hole and transferring external light to the optical sensor.

The light guide part is formed of a convex lens that collects external light.

The accommodating part includes a top chassis formed above the liquid crystal display panel, a bottom chassis formed under the liquid crystal display panel, and a front case formed above the top chassis to accommodate the liquid crystal display panel and the backlight assembly. Characterized in that.

In addition, one side of the top chassis is characterized in that it comprises a receiving unit for receiving the inverter and the inverter substrate.

On the other hand, the front case is characterized in that it comprises an opening in a position corresponding to the optical sensor.

Other technical problems and advantages of the present invention in addition to the above technical problem will be apparent from the description of the preferred embodiment of the present invention with reference to the accompanying drawings.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to FIGS. 1 to 5.

1 is an exploded perspective view illustrating a liquid crystal display according to a first embodiment of the present invention.

Referring to FIG. 1, the liquid crystal display device 150 includes a liquid crystal display panel 40, a driving circuit unit, a backlight assembly 70, an inverter (not shown), a mold frame 60, and a bottom chassis ( 90, and the top chassis 10 and the front case (5).

The liquid crystal display panel 40 includes a color filter substrate 41, a thin film transistor substrate 43 formed at a position corresponding to the color filter substrate 41, and a color filter substrate 41 and the thin film transistor substrate 43. It is formed in the liquid crystal to control the light transmittance.

The color filter substrate 41 includes a black matrix formed in a matrix on an upper substrate such as glass to block light, a red, green and blue color filter formed in a region partitioned by the black matrix to realize color; A color filter array including a common electrode for applying a common voltage to the liquid crystal and an upper alignment layer coated for liquid crystal alignment on the common electrode is formed on the upper substrate.

The thin film transistor substrate 43 includes a data line and a gate line intersecting a gate insulating film on a lower substrate such as glass, and a thin film transistor formed in a pixel region defined by the intersection of the data line and the gate line. : A thin film transistor array including a TFT), a pixel electrode for applying a pixel voltage to the liquid crystal, and a lower alignment film coated for liquid crystal alignment on the pixel electrode is formed on the lower substrate. The thin film transistor TFT includes a gate electrode connected to the gate line, a source electrode connected to the data line and formed to surround a portion of the drain electrode, and a drain electrode facing the source electrode and connected to the pixel electrode.

The liquid crystal is rotated by the difference between the common voltage from the common electrode of the color filter substrate 41 and the pixel voltage from the pixel electrode of the thin film transistor substrate to adjust the light transmittance. To this end, the liquid crystal is made of a material having dielectric anisotropy and refractive index anisotropy.

The driving circuit unit includes a gate driver integrated circuit (IC) 53 for driving gate lines of the liquid crystal display panel 40, and a data drive integrated circuit 57 for driving data lines of the liquid crystal display panel 40. ). The drive circuit section includes a timing control section, a power supply section, and various circuit elements, and generates various signals necessary for implementing an image. The timing control unit, the power supply unit, and various circuit elements are attached to the printed circuit boards (PCBs) 55 and 59.

Various signal circuits on the gate printed circuit board 55 and the data printed circuit board 59 are connected to the gate line and the data line through the gate tape carrier package (TCP) 51 and the data tape carrier package 56. Electrically connected. In addition, a power supply unit and a timing control unit mounted on the printed circuit boards 55 and 59 generate control signals and power signals using various electrical signals from the outside. The power supply unit and the timing controller on the gate printed circuit board 55 transmit driving signals and timing signals for controlling the driving and driving timing of the liquid crystal display panel 40 to the gate line through the gate drive integrated circuit 53. . The power supply unit and the timing controller on the data printed circuit board 59 transmit driving signals and timing signals for controlling the driving and driving timing of the liquid crystal display panel 40 to the data lines through the data drive integrated circuit 57. .

The backlight assembly 70 includes a lamp unit 81, a reflective sheet 85, a light guide plate 83, and an optical sheet 79.

The lamp unit 81 receives light from a cold cathode fluorescent lamp (CCFL) provided on a side surface of the light guide plate 83 installed in parallel with the liquid crystal display panel 40 by the light guide plate 83. Edge-lighting method is used. Alternatively, instead of using the light guide plate 83, a plurality of fluorescent lamps are disposed on the rear side of the diffusion sheet 71 disposed in parallel with the liquid crystal display panel 40 to directly emit light of the fluorescent lamp. Direct-lighting is also used.

The light guide plate 83 is for uniformly transmitting the light from the lamp unit 81 to the screen display area. The light guide plate 83 is a transparent acrylic material having a thickness of about several millimeters and has a plurality of dots on the bottom surface for uniform reflection of light. ) And V-shaped holes (not shown) are formed. The light guide plate 83 is formed to have a size corresponding to that of the liquid crystal display panel 40. At this time, the light guide plate 83 is unnecessary for the lamp unit 81 using the direct type method.

The reflective sheet 85 serves to reduce light loss by rereflecting light incident to the light guide plate 83 through the rear surface of the light guide plate 83 using a plate having a high light reflectance.

The optical sheet 79 injects light emitted from the light guide plate 83 into the liquid crystal display panel 40. For this purpose, the optical sheet 79 and the diffusion sheet 71 for diffusing the light incident from the light guide plate 83. The prism sheet 73 which changes the light incident from the diffusion sheet 71 so as to be outputted vertically, and the protective sheet 75 which protects the surface of the prism sheet 73 are provided. Since the optical sheet 79 vertically generates light emitted from the light guide plate 83 and enters the liquid crystal display panel 40, the light efficiency is improved.

The mold frame 60 is formed of a mold. The backlight assembly 70 is mounted on the inner optimal layer of the mold frame 60, and the liquid crystal display panel 40 is mounted to be positioned on the optical sheet 79.

The bottom chassis 90 accommodates the backlight assembly 70, and surrounds the edge area of the backlight assembly 70 and is disposed on the mold frame 60 and the top of the mold frame 60 disposed on the inner front side of the bottom chassis 90. The liquid crystal display panel 40 to be seated is stored.

An inverter for driving the lamp unit 81 has a connector for fastening with a connector formed on a conductive line branched from the lamp unit 81 to supply power to the lamp unit 81 at one end thereof. The inverter converts the DC power input from the power supply unit formed on the outside or the power supply unit mounted on the data printed circuit board 59 into an AC power supply and supplies it to the lamp unit 81. Such an inverter is housed and fixed to the inverter substrate 20.

In addition, the inverter includes an optical sensor 25 for measuring the amount of external light as shown in FIG. The optical sensor 25 is preferably formed of a photodiode or the like. The optical sensor 25 is formed under the inverter substrate 20 on which the inverter is mounted and is fixed to the inverter substrate 20 by the fixing unit 27. The inverter substrate 20 includes a hole 23 formed corresponding to the optical sensor 25. The optical sensor 25 measures the amount of external light entering through the hole 23 and transmits the amount of light to the backlight assembly 70. The received backlight assembly 70 adjusts the brightness of the lamp unit 81 according to the amount of light. If the amount of external light is measured, the brightness of the lamp unit 81 is darkened. If the amount of external light is measured, the brightness of the lamp unit 81 is brightened and displayed on the liquid crystal display panel 40. Accordingly, the power consumption of the backlight assembly 70 which uses the most power consumption in the liquid crystal display device 150 can be reduced.

The top chassis 10 protects the liquid crystal display panel 40 and the backlight assembly 70 and is open in the center thereof so that the display area of the liquid crystal display panel 40 may be exposed, and is formed of a metal material. In addition, the top chassis 10 protects the liquid crystal display panel 40 and the backlight assembly 70 by an impact applied from the outside. The top chassis 10 includes an accommodating part 15 capable of accommodating an inverter as shown in FIG. 3. Specifically, the accommodating part 15 accommodates all parts except the optical sensor 25 formed on the inverter substrate 20. This is because the external light is incident smoothly when the light sensor 25 is incident.

The front case 5 is formed on the top chassis 10 to protect the liquid crystal display panel 40, the backlight assembly 70, the driving circuit unit, and the like from external shocks. In addition, the front case 5 has an opening 7 formed at a position corresponding to the optical sensor 25.

4 is a cross-sectional view illustrating the inverter substrate and the front case taken along the line II-II ′ in FIG. 1.

Referring to FIG. 4, the optical sensor 25 is formed under the inverter substrate 20, and the inverter substrate 20 has a hole 23 formed at a position corresponding to the optical sensor 25. The front case 5 has an opening 7 formed at a position corresponding to the optical sensor 25 and the hole 23. The opening 7 and the hole 23 are formed to transmit external light to the optical sensor 25. In addition, the light guide portion 9 is formed in the opening 7. The light induction part 9 is formed so that external light is correctly transmitted to the optical sensor. The light guide portion 9 is preferably formed of a convex lens to collect the external light to the place where the optical sensor 25 is formed. Since the external light does not enter a straight line every time, the amount of external light can be measured more precisely by forming the light induction part 9. Accordingly, the low power consumption of the liquid crystal display device 150 may be realized by reducing power consumption of the backlight assembly 70 using the most power consumption of the liquid crystal display device 150.

5 is a cross-sectional view illustrating the inverter substrate and the front case according to the second embodiment of the present invention.

In the inverter substrate 20 and the front case 5 shown in FIG. 5, the light guide portion 9 is formed on the inverter substrate 20 as compared to the inverter substrate 20 and the front case 5 shown in FIG. 4. Except that it has the same components. Accordingly, detailed description of the same components will be omitted.

Referring to FIG. 5, the light guide part 9 is formed in the hole 23 of the inverter substrate 20. The light guide portion 9 is preferably formed of a convex lens to collect external light to the place where the optical sensor 25 is formed. Accordingly, power consumption of the backlight assembly 70 may be reduced by measuring external light in more detail.

As described above, the liquid crystal display device according to the present invention may include an optical sensor and a light guide part to more precisely measure the amount of external light. Accordingly, it is possible to reduce the power consumption of the backlight assembly which occupies a large portion of the power consumption used in the liquid crystal display.

In addition, even when the optical sensor is mounted off the mount in the process of mounting the inverter substrate, the light guide portion is formed to collect the light in one place, thereby preventing the performance of the optical sensor from deteriorating.

In the detailed description of the present invention described above with reference to the preferred embodiment of the present invention, those skilled in the art or those skilled in the art having ordinary knowledge of the present invention described in the claims to be described later It is apparent that various modifications and changes can be made in the present invention without departing from the spirit and scope of the invention.

Claims (12)

A liquid crystal display panel which displays an image; A backlight assembly supplying light to the liquid crystal display panel; An inverter for supplying power to the backlight assembly; An inverter substrate on which the inverter is formed; An optical sensor formed on the inverter substrate and adjusting an amount of light of the backlight assembly according to an amount of external light; An accommodating part protecting and accommodating the liquid crystal display panel and the backlight assembly; An opening formed in the housing and formed at a position corresponding to the optical sensor; And a light guide part formed in the opening part and transferring external light to an optical sensor. The method of claim 1, And the light guide part is formed of a convex lens for collecting external light. The method of claim 2, And the optical sensor is formed under the inverter substrate. The method of claim 3, wherein The inverter substrate may form a hole in a position corresponding to the optical sensor. The method of claim 4, wherein The accommodating part A top chassis formed on the liquid crystal display panel; A bottom chassis formed under the liquid crystal display panel; And a front case formed on the top chassis and accommodating a liquid crystal display panel and a backlight assembly. The method of claim 5, And an accommodation part accommodating the inverter and the inverter substrate on one side of the top chassis. The method of claim 6, And the opening is formed in the front case. A liquid crystal display panel which displays an image; A backlight assembly supplying light to the liquid crystal display panel; An accommodating part protecting and accommodating the liquid crystal display panel and the backlight assembly; An inverter for supplying power to the backlight assembly; An inverter substrate on which the inverter is formed; An optical sensor formed below the inverter substrate and configured to adjust the power according to an external light amount; A hole formed in the inter substrate and formed at a position corresponding to the optical sensor; And a light guide part formed in the hole and transmitting external light to an optical sensor. The method of claim 8, And the light guide part is formed of a convex lens for collecting external light. The method of claim 9, The accommodating part A top chassis formed on the liquid crystal display panel; A bottom chassis formed under the liquid crystal display panel; And a front case formed on the top chassis and accommodating a liquid crystal display panel and a backlight assembly. The method of claim 10, And an accommodation part accommodating the inverter and the inverter substrate on one side of the top chassis. The method of claim 11, And the front case includes an opening at a position corresponding to the optical sensor.

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