KR101664491B1 - Image display device - Google Patents

Abstract

A video display device is disclosed.
The present invention relates to an image display apparatus including a heat generating unit selectively provided with a two-dimensional image and a three-dimensional image and controlled in accordance with an image display mode. In the three-dimensional image display mode, a heat generating unit is driven to generate heat, It is possible to improve the image quality by minimizing the crosstalk phenomenon by improving the reaction speed of the liquid crystal in the display mode.

Description

IMAGE DISPLAY DEVICE [0002]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image display apparatus, and more particularly, to an image display apparatus capable of realizing a 2D image and a 3D image and improving a response speed.

Recently, stereoscopic image display devices have been widely applied to various fields such as medical images, games, advertisements, education, and military. Holography and stereoscopy are widely studied as methods for displaying stereoscopic images.

Although the holographic method is an ideal display method, it requires a coherent light source and it is difficult to record and reproduce a large object located at a long distance.

On the other hand, the stereoscopic method induces a stereoscopic effect by separating two two-dimensional images having binocular parallax into human eyes. Since this method uses two planar images, it is possible to display a three-dimensional image having a high resolution and a great depth of feeling, which is simple to implement. In this stereoscopic method, there are a spectacle using a polarized shutter and a shutter, and a non-stabilizing type using a shutter to separate the image directly from the display.

The non-eye-hardened stereoscopic image display method is generally preferred over spectacles that have disadvantages of having a disadvantage that the observation range is fixed and limited to a small number of persons but it is inconvenient to wear a separate spectacle, and a stereoscopic image is used to implement a virtual three- The parallax barriers are becoming increasingly popular.

The parallax barrier is a method in which a vertical or horizontal slit is placed in front of an image corresponding to both the left and right eyes, and the stereoscopic image synthesized through the slit is separated and observed, thereby realizing a stereoscopic effect.

A two-dimensional / three-dimensional switching display is applied to practical use of a three-dimensional display in order to overcome fatigue and the like caused by using an optical illusion of both eyes, and a parallax barrier is implemented by using a liquid crystal. That is, when power is applied to the liquid crystal, some pixels act as a barrier by blocking / absorbing light emitted from the backlight, and the remaining pixels that are not supplied with power serve as a slit of the parallax barrier Thereby realizing a stereoscopic image.

Further, when power is not applied to the liquid crystal, a parallax barrier is not formed, and the same image is transmitted to the right eye and the left eye of the viewer, and a two-dimensional image is displayed.

On the other hand, in an image display apparatus that selectively implements a two-dimensional / three-dimensional image, the duty ratio (DUTY) of the backlight differs when a two-dimensional image is displayed and a three-dimensional image is displayed on a liquid crystal display device. Specifically, the duty ratio of the backlight in the liquid crystal display device in which the three-dimensional image is implemented is lower than the duty ratio (DUTY) of the backlight of the liquid crystal display device in which the two-dimensional image is implemented.

 Accordingly, in the case of implementing a three-dimensional image, the duty ratio of the backlight of the liquid crystal display device is reduced, and the heat generated in the backlight is reduced as compared with the case of implementing the two-dimensional image. Accordingly, when the three-dimensional image is implemented, the reaction rate of the liquid crystal decreases, and a crosstalk phenomenon occurs, resulting in a problem that the image quality is deteriorated.

The present invention has a heating element for generating heat to drive the heating element in a three-dimensional image display mode selected by a user to improve the reaction speed of the liquid crystal in the three-dimensional image display mode, thereby minimizing the crosstalk phenomenon and improving the image quality The present invention is directed to a video display device capable of displaying a video signal.

According to an embodiment of the present invention, there is provided an image display apparatus for selectively displaying a two-dimensional image and a three-dimensional image, the image display apparatus comprising: a light source unit for providing light; A driving unit for supplying a driving signal to the display panel; a control unit for controlling the driving unit and the light source unit to generate a control signal according to an image selected from a two-dimensional image or a three-dimensional image; And a heating unit disposed on at least one side of the display panel, the heating unit being configured to generate heat in response to a control signal generated by the control unit, And temperature sensing means for determining whether or not the temperature of the heat generated in the heating section is lower than or equal to a reference temperature Wherein the control unit generates a switch control signal for controlling the switch unit to be on when the temperature of the heat generated by the heating unit is less than a reference temperature, When the temperature of the heat is higher than the reference temperature, a switch control signal for controlling the switch unit to be in an off state may be generated and provided to the switch unit.

The image display apparatus according to the present invention includes a switch unit that is turned on / off according to a display mode selected by a user in a two-dimensional / three-dimensional display mode, and a heating unit that is controlled by the switch unit and generates heat, It is possible to improve the image quality by minimizing the crosstalk phenomenon by generating heat in the image display mode to improve the reaction speed of the liquid crystal.

1 is a schematic view illustrating an image display apparatus according to an embodiment of the present invention.
FIG. 2 is a circuit diagram showing the switch unit and the heat generating unit of FIG. 1;
FIG. 3 is a flowchart showing the operation sequence of the switch unit and the heat generating unit of FIG. 1;
FIG. 4A is a view showing the positions of the heat generating units arranged for respective regions of the display panel, and FIG. 4B is a diagram showing temperature changes measured in each region of FIG. 4A.

Hereinafter, embodiments according to the present invention will be described with reference to the accompanying drawings.

1 is a schematic view illustrating an image display apparatus according to an embodiment of the present invention.

1, an image display apparatus 100 according to an embodiment of the present invention includes a light source unit 120, a light source unit 120, and a light source unit 120. The image display apparatus 100 includes a light source unit 120, A polarizing switching unit 135 for outputting two polarized lights and a slit 150 and a parallax barrier 155 in which the barriers 160 are arranged alternately and the parallax barrier 155, And a display panel 170 for displaying an image by modulating the modulated image.

The display panel 170 may be implemented as a transmissive display device, for example, a liquid crystal display device. In the case of applying a liquid crystal display element to the display panel 170, a liquid crystal layer is formed between the two glass substrates of the display panel 170.

A TFT array is formed on the lower glass substrate. The TFT array includes a plurality of data lines to which a data voltage is supplied, and a plurality of gate lines which intersect the plurality of data lines to define a pixel region, A plurality of TFTs formed in the pixel region, a plurality of pixel electrodes for charging a data voltage to the liquid crystal cells, and a storage capacitor connected to the pixel electrode to maintain a voltage of the liquid crystal cell.

A color filter array is formed on the upper glass substrate, which includes a black matrix, a color filter, and the like. A column spacer for maintaining a cell gap of the liquid crystal cell may be formed between the lower and upper glass substrates.

The light source unit 120 may include a reflection plate 110 to enable the light reflected from the barrier 160 to be recycled. The light source unit 120 generally illuminates non-polarized light, and the polarization switching unit 135 includes polarization means for transmitting linearly polarized light by electrically controlling light of unpolarized light illuminated by the light source unit 120 And a phase delay unit 140 for converting the polarized light of the light transmitted through the polarizing unit 130 into polarized light orthogonal to the polarized light according to an electrical signal. The dual retardation unit 140 may be a dual brightness enhancement film (DBEF) .

The phase delay means 140 changes the polarized light by delaying the phase of the incident light. For example, when there is no electrical signal, the phase delay means 140 transmits the incident light as it is without phase delay, The phase of the incident light is delayed and converted into orthogonal polarized light.

The parallax barrier 155 is for forming a three-dimensional image by a binocular parallax in which slits 150 for transmitting light and a barrier 160 for blocking light are alternately arranged. The arrangement of the slit 150 and the barrier 160 can be variously changed.

The display panel 170 modulates the light transmitted through the parallax barrier 155 according to an image signal to form an image.

The image display apparatus 100 according to the embodiment of the present invention may further include a first driving unit 190 for driving the display panel 170 and a second driving unit 190 for driving the light source unit 120 and the polarization switching unit 135 A control unit 180 for controlling the first and second driving units 190 and 200, and a control unit 180 for controlling on / off according to the display mode selected by the user in the two-dimensional / three- And a heating unit 220 for generating heat under the control of the switch unit 210. The heating unit 220 may be a heater,

 In addition, the image display apparatus 100 may further include temperature sensing means (not shown) for determining whether the temperature of the heat generating unit 220 corresponds to a predetermined temperature level.

The first driver 190 may include a data driver for supplying a data voltage to the data lines of the display panel 170, a gate driver for sequentially supplying scan pulses to the gate lines of the display panel 170, And a common voltage generator for supplying a common voltage to the common electrode of the display panel 170.

The second driving unit 200 controls the on / off time of the backlight provided in the light source unit 120 according to a control signal provided from the controller 180 and drives the light source, RTI ID = 0.0 > 135 < / RTI >

The controller 180 controls the first and second drivers 190 and 200 and generates a switch control signal for controlling the switch unit 210 according to the display mode selected by the user. The switch control signal generated by the controller 180 is provided to the switch unit 210.

When the user selects the two-dimensional display mode, the control unit 180 generates a switch control signal of a low logic level and generates a switch control signal of a high logic level when the user selects the three-dimensional display mode do. The controller 180 may include temperature sensing means for determining whether the heat generated by the heat generating unit 220 corresponds to a reference temperature set by an engineer. The controller 180 controls the heat generation of the heat generating unit 220 by the temperature sensing unit.

The switch unit 210 is turned on / off according to the logic level of the switch control signal from the controller 180. The switch unit 210 is turned on by a switch control signal of a high logic level and turned off by a switch control signal of a logic low level, for example.

The heating unit 220 generates heat when the switch unit 210 is turned on and does not generate heat when the switch unit 210 is turned off.

2, the switch unit 210 may include a FET (Field Effect Transistor) switch device, and the heat generating unit 220 may include a metal resistor. The switch unit 210 may include all elements that can be turned on and off by a switch control signal from the controller 180. The heater 220 may include a metal resistor And all of the elements capable of generating heat.

At least one switch unit 210 and a plurality of heat generating units 220 may be provided in the image display apparatus 100.

A switch control signal provided from the controller 180 is supplied to the gate terminal G of the FET switch element and the FET switch element is turned on when the switch control signal is at a high logic level. When the FET switch element is turned on, current flows through the metal resistor R to generate heat.

The FET switch element is turned off when the switch control signal is at a low logic level. When the FET switch element is turned off, no current flows through the metal resistor R, and the metal resistor R does not generate heat.

That is, the switch unit 210 is turned off when the image display apparatus 100 is driven in the two-dimensional display mode and turned on when the image display apparatus 100 is driven in the three- do. Similarly, the heat generating unit 220 generates heat when the image display apparatus 100 is driven in the two-dimensional display mode, and generates heat when the image display apparatus 100 is driven in the three-dimensional display mode.

When the image display apparatus 100 is driven in a display mode for displaying a three-dimensional image, the heat generating unit 220 generates heat of a predetermined temperature. Due to such heat, The response speed of the liquid crystal can be improved.

When the image display apparatus 100 is driven in the three-dimensional display mode, the duty ratio of the backlight provided in the light source unit 120 (FIG. 1) decreases, The speed is reduced.

In order to compensate for this, the image display apparatus 100 according to the embodiment of the present invention includes the heat generating unit 220, and when the image display apparatus 100 is driven in the three-dimensional display mode, Thereby generating a heat of a certain temperature, thereby improving the reaction speed of the liquid crystal provided on the display panel 170.

Accordingly, when the image display apparatus 100 according to the embodiment of the present invention is driven in a display mode for displaying a three-dimensional image, the heat generating unit 220 is driven to generate heat of a predetermined temperature, It is possible to improve the image quality by compensating the response speed of the liquid crystal which may occur due to the reduction of the duty ratio of the backlight (DUTY).

Meanwhile, the temperature sensing means provided in the controller 180 determines whether the temperature of the heat generated in the heat generating unit 220 is lower than a reference temperature (for example, 37 ° C) and controls the switch unit 210 . For example, when the temperature of the heat generated by the heat generating unit 220 is lower than the reference temperature, the temperature sensing unit maintains the on state of the switch unit 210. When the temperature of the heat generated by the heat generating unit 220 is higher than the reference temperature, the temperature sensing unit controls the on state of the switch unit 210 to be off. Therefore, when the temperature of the heat generated in the heat generating unit 220 is higher than the reference temperature, the heat generating unit 220 does not generate heat.

FIG. 3 is a flowchart showing the operation sequence of the switch unit and the heat generating unit of FIG. 1;

1 and 3, when the display mode selected by the user when the image display apparatus 100 is powered on is the three-dimensional display mode, the controller 180 controls the switch unit 210 And provides a high level switch control signal.

The switch unit 210 is turned on to allow the current to flow to the heat generating unit 220 so that the heat generating unit 220 generates heat. The temperature sensing unit provided in the controller 180 determines whether the temperature of the heat generated in the heat generating unit 220 is 37 ° C. or less after the heating unit 220 generates heat.

When the temperature of the heat generated in the heat generating unit 220 is 37 ° C or lower, the switch unit 210 is maintained in the on state to allow the heat generating unit 220 to generate heat.

On the other hand, when the temperature of the heat generated in the heat generating unit 220 is higher than 37 ° C, the switch unit 210 is turned off to prevent the heat generating unit 220 from generating heat.

When the display mode selected by the user is a two-dimensional display mode, the controller 180 provides a switch control signal of a low level to the switch unit 210. The switch unit 210 is turned off by the switch control signal of the low level to prevent the heat generating unit 220 from generating heat.

As described above, when the image display apparatus according to the embodiment of the present invention is driven in the display mode for displaying a three-dimensional image, the heat generating unit 220 is driven to generate heat of a predetermined temperature, It is possible to compensate the response speed of the liquid crystal which may occur due to the decrease of the duty ratio, thereby preventing crosstalk and improving the image quality.

Table 1 below shows the relationship between the display panel internal temperature and crosstalk.

Table 1 shows that when the temperature of the central part of the display panel is 30 ° C, 35 ° C, 40 ° C and 45 ° C, the change in the nit (nit) shown at the center of the display panel is not large, (C / T) decreases as the temperature rises. This is because the display panel has a heat generating portion to increase the internal temperature of the display panel, thereby improving the reaction speed of the liquid crystal.

Measuring temperature ℃ 30 35 40 45
Luminance
(center)
①W → W

nit
46.63 45.78 45.83 44.93 ②B → W 37.78 40.9 41.9 41.98 ③WB 3.857 3.137 2.324 1.828 ④B⇒B 0.042 0.039 0.039 0.040 3D C / T % 10.1 7.6 5.5 4.3

As shown in FIGS. 4A and 4B, when nine heat generating units are provided for each region of the display panel, the temperature is measured for each region, and the central portions 3, 6, (46.2 ° C, 43.6 ° C and 46.7 ° C), respectively, as compared with the case where the temperature is higher than the reference temperature (2, 4, 5, 7, 8) Therefore, when the heat generating portion is provided at the central portion of the display panel, the internal temperature rises as compared with the case where the heat generating portion is provided in another region, so that the reaction speed of the liquid crystal can be improved.

100: Image display device 110: Reflector
120: light source unit 130: polarizing means
135: switching polarization unit 140: phase delay means
150: Slit 155: Parallax barrier
160: Barrier 170: Display panel
180: control unit 190: first driving unit
200: second driving part 210: switch part
220:

Claims (8)

An image display apparatus for selectively providing a two-dimensional image and a three-dimensional image,
A light source unit for providing light;
A display panel selectively providing a two-dimensional image and a three-dimensional image using light provided from the light source unit;
A driving unit for supplying a driving signal to the display panel;
A controller for controlling the driving unit and the light source unit and generating different control signals according to images selected from two-dimensional images or three-dimensional images;
A switch unit which is turned on / off according to a control signal generated by the control unit; And
And at least one or more heaters that are disposed in the region of the display panel and generate heat by the ON state of the switch unit,
Wherein the controller includes temperature sensing means for determining whether the temperature of the heat generated in the heat generating unit is lower than a reference temperature,
Wherein the control unit generates a switch control signal for controlling the switch unit to be on when the temperature of the heat generated by the heat generating unit is less than a reference temperature and the temperature of the heat generated in the heat generating unit The control unit generates a switch control signal for controlling the switch unit to be in the off state and provides the switch control signal to the switch unit. delete delete The method according to claim 1,
Wherein the switch unit includes a field effect transistor (FET) that is turned on / off by the switch control signal. The method according to claim 1,
And the heating unit includes a metal resistor which is controlled and heated by the switch. delete delete The method according to claim 1,
Wherein the display panel is a liquid crystal display device.

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