KR101152133B1 - Temperature sensor for display device, thin film transistor array panel including temperature sensor, and liquid crystal display - Google Patents

Abstract

The present invention relates to a temperature sensor for a display device having a plurality of pixels, a plurality of gate lines, and a plurality of data lines. The temperature sensor includes a temperature sensing line formed on a substrate, and the temperature sensing line is a conductor. The temperature sensing line is formed on the same layer as the gate line, and includes a lower layer made of aluminum and an upper layer made of molybdenum. As described above, since the temperature sensor is made of only metal that is not affected by light, the temperature of the display device can be accurately controlled without being affected by light, thereby increasing the reliability of the temperature sensor.

Sensor, temperature sensor, liquid crystal display, thin film transistor display panel, resistor, metal wiring, conductor

Description

TEMPERATURE SENSOR FOR DISPLAY DEVICE, THIN FILM TRANSISTOR ARRAY PANEL INCLUDING TEMPERATURE SENSOR, AND LIQUID CRYSTAL DISPLAY}

1 is a block diagram of a liquid crystal display according to an exemplary embodiment of the present invention.

2 is an equivalent circuit diagram of one pixel of a liquid crystal display according to an exemplary embodiment of the present invention.

3 is an exploded perspective view of a liquid crystal display according to an exemplary embodiment of the present invention.

4 is an example of a layout view of a thin film transistor array panel according to an exemplary embodiment of the present invention.

5 to 7 are cross-sectional views of the thin film transistor array panel illustrated in FIG. 4 taken along the lines V-V, VI-VI, and VII-VII, respectively.

8 is an equivalent circuit diagram of a temperature sensor according to an embodiment of the present invention.

9 is a graph showing the characteristics of the voltage according to the temperature change output from the temperature sensor according to an embodiment of the present invention.

10 is a block diagram of a signal controller according to another embodiment of the present invention.

The present invention relates to a temperature sensor for a display device, a thin film transistor array panel having the same, and a liquid crystal display device.

The display device includes a cathode ray tube, an organic light emitting display (OLED), and a plasma display (PDP, plasma display) that emit light by itself and requires a separate light source. Liquid crystal displays, and the like.

The liquid crystal display device generally includes two display panels and a liquid crystal layer having dielectric anisotropy interposed therebetween. The desired image is obtained by applying an electric field to the liquid crystal layer and adjusting the intensity of the electric field to adjust the transmittance of light passing through the liquid crystal layer. In this case, the light may be an artificial light source separately provided or natural light.

Since the optical properties of the liquid crystal filled in the liquid crystal layer change with temperature, it is preferable to consider the temperature change of the liquid crystal display device. For example, optical properties of the liquid crystal, such as refractive index, dielectric constant, elastic modulus, viscosity, etc. are inversely related to the thermal kinetic energy of the liquid crystal molecules, it is known that the value tends to decrease as the temperature of the liquid crystal increases.

In addition, operating characteristics such as circuit elements mounted or mounted to drive the liquid crystal display are also affected by temperature, and thus, the operating characteristics change with temperature.

As the optical characteristics and the circuit elements of the liquid crystal change according to the temperature change as described above, in order to drive the liquid crystal display, it is necessary to detect the temperature change of the liquid crystal display due to the heat generated from the surrounding environment or the inside. have.

To this end, a temperature sensor is mounted on a printed circuit board (PCB) equipped with a plurality of driving circuits to detect a temperature change of the liquid crystal display. However, the printed circuit board is usually mounted on the rear side of the liquid crystal display device, not on the front surface thereof, and thus, the temperature of the liquid crystal display device in which the liquid crystal layer is in direct contact with the outside is formed, not the temperature of the artificial light source and many electrical sources. Due to the heat generated from the device, the temperature of the rear side of the liquid crystal display with a large temperature deviation from the outside is sensed.

As a result, the temperature sensed by the temperature sensor is greatly different from the actual temperature of the liquid crystal layer, so that an accurate temperature compensation operation considering the temperature of the liquid crystal layer cannot be performed. In addition, a separate temperature sensor must be attached to the PCB, which leads to space limitations and economic burden.

Accordingly, an object of the present invention is to provide a sensor for accurately sensing the temperature of a display device.

Another technical problem to be achieved by the present invention is to reduce the cost increase due to the temperature sensing sensor.

Another technical problem to be achieved by the present invention is to reduce the spatial limitation for attaching the sensor.

Another technical problem to be achieved by the present invention is to perform accurate temperature sensing.

Another object of the present invention is to provide a display device in which a stable display operation is performed according to a temperature change.

According to an exemplary embodiment of the present invention, a temperature sensor for a display device includes a display device substrate and a temperature sensing line formed on the substrate, and the temperature sensing line is a conductor.

It is preferable to meander the said temperature sensing line.

The temperature sensing line may include a lower layer made of aluminum (Al) or an aluminum alloy and an upper layer made of molybdenum (Mo) or molybdenum alloy.

In addition, the temperature sensing line may be made of one of aluminum, copper (Cu), platinum (Pt), chromium (Cr), and molybdenum.

The temperature sensing line may further include an insulating film, and the insulating film may have first and second contact holes exposing both ends of the temperature sensing line.

Preferably, the apparatus further includes a contact auxiliary member connected to an end portion of the temperature sensing line through the first and second contact holes.

The contact assistant may be made of ITO or IZO.

The specific resistance of the temperature sensing line is preferably changed linearly with temperature change.

The display device may include a gate line formed on the substrate, a first insulating film formed on the gate line, a data line formed on the first insulating film, and a second insulating film formed on the data line. Can be.

The temperature sensing line may be formed on the same layer as the gate line or on the same layer as the data line.

The data line may include a lower layer made of molybdenum or molybdenum alloy, an intermediate layer made of aluminum or aluminum alloy, and an upper layer made of molybdenum or molybdenum alloy.

The first or second insulating layer may have first and second contact holes exposing both ends of the temperature sensing line, respectively.

The display device may further include a contact auxiliary member connected to an end portion of the temperature sensing line through the first and second contact holes, and the contact auxiliary member may be made of ITO or IZO.

The display device may be a liquid crystal display device.

A thin film transistor array panel according to another aspect of the present invention includes a substrate, a thin film transistor formed on the substrate and having a gate electrode, a source and a drain electrode, and a temperature sensing line formed on the substrate.

The temperature sensing line is formed on the same layer as the gate electrode or the source and drain electrodes.

It is preferable to meander the said temperature sensing line.

The temperature sensing line may include a lower layer made of aluminum (Al) or an aluminum alloy and an upper layer made of molybdenum (Mo) or molybdenum alloy.

In addition, the temperature sensing line may be made of one of aluminum, copper (Cu), platinum (Pt), chromium (Cr), and molybdenum.

The temperature sensing line may include a lower film made of molybdenum or molybdenum alloy, an intermediate film made of aluminum or aluminum alloy, and an upper film made of molybdenum or molybdenum alloy.

The specific resistance of the temperature sensing line is preferably changed linearly with temperature change.

The pixel electrode may further include a pixel electrode connected to the thin film transistor, and the pixel electrode may be made of ITO or IZO.

The thin film transistor array panel according to the above feature may further include an insulating layer formed on the temperature sensing line.

The insulating layer may include a first layer formed on the gate electrode and a second layer formed on the source and drain electrodes.

The second layer preferably has a first contact hole exposing a portion of the drain electrode.

Preferably, the first or second layer has second and third contact holes that expose both ends of the temperature sensing line, respectively.

The thin film transistor array panel according to the above feature may further include contact auxiliary members connected to both ends of the temperature sensing line through the second and third contact holes, respectively.

The contact assistant may be formed on the same layer as the pixel electrode.

According to still another aspect of the present invention, there is provided a display device including a plurality of pixels, a first signal line connected to the pixel, a second signal line connected to the pixel and crossing the first signal line, and the first and second signals. And a temperature sensing line spaced apart from the two signal lines, wherein the temperature sensing line is formed on the same layer as the first or second signal line.

The display device may further include a signal controller configured to control the display of the pixel based on the signal from the temperature sensing line.

The display device may further include a data driver for converting the corrected image signal from the signal controller to a data signal and applying the gate signal for controlling the operation of the pixel to the second signal line. It may include.

The signal controller may be configured to receive an image signal from the outside and to output the corrected image signal by correcting the image signal based on a previous image signal, and the correction of the image signal may vary depending on the signal from the temperature sensing line. .

DETAILED DESCRIPTION Embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art may easily practice the present invention.

In the drawings, the thickness of layers, films, panels, regions, etc., are exaggerated for clarity. Like parts are designated by like reference numerals throughout the specification. When a portion of a layer, film, region, plate, etc. is said to be "on top" of another part, this includes not only when the other part is "right on" but also another part in the middle. On the contrary, when a part is "just above" another part, there is no other part in the middle.

A temperature sensor for a display device, a thin film transistor array panel having the same, and a liquid crystal display device according to an exemplary embodiment of the present invention will now be described in detail with reference to the accompanying drawings.

1 is a block diagram of a liquid crystal display according to an embodiment of the present invention, FIG. 2 is an equivalent circuit diagram of one pixel of the liquid crystal display according to an embodiment of the present invention, and FIG. 3 is an embodiment of the present invention. An exploded perspective view of a liquid crystal display device according to an example.

As shown in FIG. 1, a liquid crystal display according to an exemplary embodiment of the present invention includes a liquid crystal panel assembly 300, a gate driver 400, a data driver 500, and a data driver The gray voltage generator 800, the temperature sensor 50, and the signal controller 600 controlling the gray voltage generator 800 connected to the 500 are included.

The liquid crystal panel assembly 300 may include a plurality of signal lines G ₁ -G _n , D ₁ -D _m and a plurality of pixels PX connected to the plurality of signal lines G ₁ -G _n , D ₁ -D _m , and arranged in a substantially matrix form. Include. 2, the liquid crystal display panel assembly 300 includes lower and upper display panels 100 and 200 facing each other and a liquid crystal layer 3 interposed therebetween.

The signal lines G ₁ -G _n and D ₁ -D _m are a plurality of gate lines G ₁ -G _n for transmitting a gate signal (also called a “scan signal”) and a plurality of data lines for transmitting a data signal ( D ₁ -D _m ). The gate lines G ₁ -G _n extend substantially in the row direction and are substantially parallel to each other, and the data lines D ₁ -D _m extend substantially in the column direction and are substantially parallel to each other.

Each pixel PX, for example, the i-th (i = 1, 2, ..., n) gate line G _i and the j-th (j = 1, 2, ..., m) data line D _The pixel PX connected to _j ) includes a switching element Q connected to the signal line G _i D _j , a liquid crystal capacitor C _LC , and a storage capacitor C _ST connected thereto. do. The holding capacitor C _ST can be omitted as necessary.

The switching element Q is a three-terminal element of a thin film transistor or the like provided in the lower panel 100, the control terminal of which is connected to the gate line G _i , and the input terminal of which is connected to the data line D _j . The output terminal is connected to the liquid crystal capacitor C _LC and the storage capacitor C _ST .

The liquid crystal capacitor C _LC has two terminals, a pixel electrode 191 of the lower panel 100 and a common electrode 270 of the upper panel 200, and a liquid crystal layer 3 between the two electrodes 191 and 270. It functions as a dielectric. The pixel electrode 191 is connected to the switching element Q, and the common electrode 270 is formed on the front surface of the upper panel 200 and receives the common voltage Vcom. Unlike in FIG. 2, the common electrode 270 may be provided in the lower panel 100. In this case, at least one of the two electrodes 191 and 270 may be formed in a linear or bar shape.

The storage capacitor C _ST , which serves as an auxiliary part of the liquid crystal capacitor C _LC , is formed by overlapping a separate signal line (not shown) and the pixel electrode 191 provided on the lower panel 100 with an insulator interposed therebetween. A predetermined voltage such as the common voltage Vcom is applied to this separate signal line. However, the storage capacitor C _ST may be formed such that the pixel electrode 191 overlaps the front gate line directly above the insulator.

On the other hand, in order to implement color display, each pixel PX uniquely displays one of primary colors (space division), or each pixel PX alternately displays a basic color (time division) So that the desired color is recognized by the spatial and temporal sum of these basic colors. Examples of basic colors include red, green, and blue. A light blocking member 220 (hatched in FIG. 2), such as a black matrix, is formed on the upper panel 200 to block light leakage, and the light blocking member 220 is the pixel electrode 191 or the color filter 230. It has an opening in the area | region corresponding to it. FIG. 2 illustrates that each pixel PX includes a color filter 230 representing one of the primary colors in an area of the upper panel 200 corresponding to the pixel electrode 191 as an example of spatial division. Unlike FIG. 2, the color filter 230 may be formed above or below the pixel electrode 191 of the lower panel 100.

At least one polarizer (not shown) for polarizing light is attached to an outer surface of the liquid crystal panel assembly 300.

Referring back to FIG. 1, the gray voltage generator 800 generates two sets of gray voltage sets (or reference gray voltage sets) related to the transmittance of the pixel PX. One of the two sets has a positive value for the common voltage Vcom and the other set has a negative value.

A gate driver 400, a gate line (G ₁ -G _n) and is connected to the gate turn-on voltage (Von), and a gate signal consisting of a combination of a gate-off voltage (Voff), a gate line (G ₁ of the liquid crystal panel assembly 300 -G _n ).

The data driver 500 is connected to the data lines D ₁ -D _m of the liquid crystal panel assembly 300 and selects a gray voltage from the gray voltage generator 800 and uses the data line D ₁ as a data signal. -D _m ). However, when the gray voltage generator 800 provides only a predetermined number of reference gray voltages instead of providing all of the voltages for all grays, the data driver 500 divides the reference gray voltages to divide the gray voltages for all grays. Generate and select the data signal from it.

The temperature sensor unit 50 is made in the liquid crystal panel assembly 300 and includes a temperature sensor 51. The temperature sensor 51 generates a temperature sensing signal Vs corresponding to the sensed temperature and outputs it to the signal controller 600.

Meanwhile, as shown in FIG. 3, the liquid crystal panel assembly 300 is divided into a display area DA in which the liquid crystal layer 3 is mainly formed and a peripheral area BA except for the display area DA, and the peripheral area. BA is mainly at the edge of the liquid crystal panel assembly 300 and covered with the light blocking member 220. The temperature sensor 51 of the temperature sensor unit 50 is located in the peripheral area BA of these areas.

Unlike in FIG. 1, as illustrated in FIG. 3, four or two temperature sensors 51 may be manufactured, respectively, at the upper and lower sides of the liquid crystal panel assembly 300. The present invention is not limited thereto, and may be any number and positions capable of sensing the temperature of the liquid crystal panel assembly 300, such as the left and right sides of the liquid crystal panel assembly 300.

The signal controller 600 controls the gate driver 400, the data driver 500, and the like based on the temperature detection signal Vs from the temperature sensor 50.

Each of the driving devices 400, 500, 600, and 800 may be mounted directly on the liquid crystal panel assembly 300 in the form of at least one integrated circuit chip, or may be a flexible printed circuit film (not shown). It may be mounted on the liquid crystal panel assembly 300 in the form of a tape carrier package (TCP) or mounted on a separate printed circuit board (not shown). Alternatively, these driving devices 400, 500, 600, and 800 may be integrated in the liquid crystal panel assembly 300 together with the signal lines G ₁ -G _n , D ₁ -D _m and the thin film transistor switching element Q. It may be. In addition, the driving devices 400, 500, 600, and 800 may be integrated into a single chip, in which case at least one of them or at least one circuit element constituting them may be outside the single chip.

As described above, the liquid crystal panel assembly 300 includes two display panels 100 and 200, and the lower panel 100 having the double thin film transistor is referred to as a "thin film transistor display panel". Since the temperature sensor 51 and the like of the temperature sensor unit 50 are provided in the thin film transistor array panel 100, the structure of the thin film transistor array panel 100 will be described in detail with reference to FIGS. 4 to 7.

4 is a layout view of a thin film transistor array panel according to an exemplary embodiment of the present invention, and FIGS. 5 to 7 respectively show the thin film transistor array panel illustrated in FIG. 4 along VV, VI-VI, and VII-VII lines. One cross section.

A plurality of gate lines 121, a temperature sensing line 125, and a plurality of storage electrode lines 131 are formed on an insulating substrate 110 made of transparent glass or plastic.

The gate line 121 transmits the gate signal and extends mainly in the horizontal direction. Each gate line 121 includes an end portion 129 having a large area for connecting a plurality of gate electrodes 124 to another layer or an external driving circuit. A gate driving circuit (not shown) for generating a gate signal may be mounted on a flexible printed circuit film (not shown) attached on the substrate 110, directly mounted on the substrate 110, And may be integrated on the substrate 110. When the gate driving circuit is integrated on the substrate 110, the gate line 121 may extend to be directly connected to the gate driving circuit.

The temperature sensing line 125 extends in the horizontal direction while meandering. As such, when the length of the temperature sensing line 125 is increased to increase resistance, sensitivity to temperature increases.

 Both ends of the temperature sensing line 125 include end portions 126 and 127 having a large area for inputting / outputting an external driving signal or connecting to an external driving circuit. In this case, the end portion 126 is an input terminal receiving a signal and the other end portion 127 serves as an output terminal for outputting a signal, but may be interchanged.

The storage electrode line 131 receives a predetermined voltage, and includes a stem line extending substantially in parallel with the gate line 121 and a plurality of pairs of storage electrodes 133a and 133b separated therefrom. Each of the storage electrode lines 131 is positioned between two adjacent gate lines 121, and the stem line is closer to the lower side of the two gate lines 121. Each of the sustain electrodes 133a and 133b has a fixed end connected to the stem line and a free end opposite thereto. The fixed end of one sustain electrode 133b has a large area, and its free end is divided into two parts, a straight part and a bent part. However, the shape and arrangement of the storage electrode line 131 may be modified in various ways.

The gate line 121, the temperature sensing line 125, and the storage electrode line 131 include two conductive layers having different physical properties, that is, a lower layer and an upper layer thereon. The lower layer is made of a low resistivity metal such as aluminum (Al) or aluminum alloy to reduce signal delay or voltage drop, silver based metal such as silver (Ag) or silver alloy, copper (Cu) or copper alloy Etc. are made of copper-based metals. On the other hand, the top film is a material having excellent physical, chemical and electrical contact properties with other materials, particularly indium tin oxide (ITO) or indium zinc oxide (IZO), metals such as molybdenum-based metals such as molybdenum (Mo) or molybdenum alloys and their It is made of nitride, chromium (Cr), tantalum (Ta) and titanium (Ti). A good example of such a combination is an aluminum (alloy) bottom film and a molybdenum (alloy) top film.

However, the lower layer is a material having excellent contact characteristics, and the upper layer may be made of a low resistance material. A portion of the upper layers 126q and 127q of the first and second portions 127 and 127 may be removed to expose the lower layers 129p, 126p and 127p. In addition, the gate line 121, the temperature sensing line 125, and the storage electrode line 131 may have a single layer structure including various materials mentioned above, and may be made of various other various metals or conductors. .

In FIG. 5, the lower layer of the gate electrode 124, the temperature sensing line 125, and the storage electrode line 131 is denoted by the letter p and the letter q as the upper layer.

Side surfaces of the gate line 121, the temperature sensing line 125, and the storage electrode line 131 may be inclined at an inclination angle of about 30 ° to about 80 ° with respect to the surface of the substrate 110, and the gate line 121, The temperature sensing line 125 and the storage electrode line 131 may be formed by sputtering or the like.

A gate insulating layer 140 made of silicon nitride (SiNx) or silicon oxide (SiOx) is formed on the gate line 121, the temperature sensing line 125, and the storage electrode line 131.

A plurality of linear semiconductors 151 made of hydrogenated amorphous silicon (hereinafter referred to as a-Si) or polysilicon are formed on the gate insulating layer 140. The linear semiconductor 151 mainly extends in the longitudinal direction and includes a plurality of projections 154 extending toward the gate electrode 124. The width of the linear semiconductor 151 in the vicinity of the gate line 121 and the storage electrode line 131 is widened to cover them extensively.

A plurality of linear and island ohmic contacts 161 and 165 are sequentially formed on the semiconductor 151. The ohmic contacts 161 and 165 may be made of a material such as n + hydrogenated amorphous silicon in which n-type impurities such as phosphorus are heavily doped, or may be made of silicide. The linear ohmic contact 161 has a plurality of protrusions 163, and the protrusion 163 and the island-type ohmic contact 165 are paired and disposed on the protrusion 154 of the semiconductor 151.

Side surfaces of the semiconductor 151 and the ohmic contacts 161 and 165 are also inclined with respect to the surface of the substrate 110, and the inclination angle is about 30 ° to 80 °.

A plurality of data lines 171 and a plurality of drain electrodes 175 are formed on the ohmic contacts 161 and 165 and the gate insulating layer 140 by sputtering or the like.

The data line 171 transmits a data signal and mainly extends in the vertical direction to cross the gate line 121. Each data line 171 also crosses the storage electrode line 131 and runs between adjacent sets of storage electrodes 133a and 133b. Each data line 171 includes a plurality of source electrodes 173 extending toward the gate electrode 124 and an end portion 179 having a large area for connection with another layer or an external driving circuit. A data driving circuit (not shown) for generating a data signal is mounted on a flexible printed circuit film (not shown) attached to the substrate 110, directly mounted on the substrate 110, or integrated in the substrate 110. Can be. When the data driving circuit is integrated on the substrate 110, the data line 171 can extend and be directly connected thereto. The drain electrode 175 is separated from the data line 171 and faces the source electrode 173 around the gate electrode 124.

Each drain electrode 175 has one wide end portion and the other end having a rod shape, and the rod end portion is partially surrounded by the bent source electrode 173.

One gate electrode 124, one source electrode 173, and one drain electrode 175 together with the protrusion 154 of the semiconductor 151 form one thin film transistor (TFT). A channel of the transistor is formed in the protrusion 154 between the source electrode 173 and the drain electrode 175.

The data line 171 and the drain electrode 175 are preferably made of a refractory metal such as molybdenum, chromium, tantalum, and titanium, or an alloy thereof, and include a refractory metal film (not shown) and a low resistance conductive film. It may have a multilayer structure including (not shown). Examples of the multilayer structure include a double film of a chromium or molybdenum (alloy) lower film and an aluminum (alloy) upper film, a molybdenum (alloy) lower film, an aluminum (alloy) intermediate film and a molybdenum (alloy) upper film. However, the data line 171 and the drain electrode 175 may be made of various metals or conductors.

The side of the data line 171 and the drain electrode 175 may also be inclined at an inclination angle of about 30 ° to about 80 ° with respect to the surface of the substrate 110.

The data line 171 and the drain electrode 175 may be formed by sputtering or the like.

The ohmic contacts 161 and 165 exist only between the semiconductor 151 below and the data line 171 and the drain electrode 175 thereon, and lower the contact resistance therebetween. The semiconductor 151 has a portion exposed between the source electrode 173 and the drain electrode 175 and not covered by the data line 171 and the drain electrode 175. In most places, the width of the linear semiconductor 151 is smaller than the width of the data line 171. However, as described above, the width of the linear semiconductor 151 is widened at the portion where it meets the gate line 121 to smooth the profile of the surface. Prevents disconnection.

A passivation layer 180 is formed on the data line 171, the drain electrode 175, and the exposed semiconductor 151. The passivation layer 180 may be made of an inorganic insulator or an organic insulator, and may have a flat surface. Examples of the inorganic insulating material include silicon nitride and silicon oxide. The organic insulator may have photosensitivity and its dielectric constant is preferably about 4.0 or less. However, the passivation layer 180 may have a double layer structure of the lower inorganic layer and the upper organic layer so as not to damage the exposed portion of the semiconductor 151 while maintaining excellent insulating properties of the organic layer.

In the passivation layer 180, a plurality of contact holes 182 and 185 exposing the data line 171 end portion 179 and the drain electrode 175 are formed, respectively, and the passivation layer 180 and the gate insulating layer ( 140 includes a plurality of contact holes 181 exposing the upper layer 129q of the end portion 129 of the gate line 121, and upper layers 126q of the end portions 126 and 127 of the temperature sensing line 125. Contact holes 186 and 187 exposing 127q respectively, a plurality of contact holes 183a exposing a part of the sustain electrode line 131 near the fixed end of the sustain electrode 133b, and a straight portion of the free end of the sustain electrode 133a. A plurality of contact holes 183b are also formed.

A plurality of pixel electrodes 191, a plurality of overpasses 83, and a plurality of contact assistants 81, 82, 86, and 87 are formed on the passivation layer 180. have. They may be made of a transparent conductive material such as ITO or IZO or a reflective metal such as aluminum, silver, chromium or an alloy thereof.

The pixel electrode 191 is physically and electrically connected to the drain electrode 175 through the contact hole 185 and receives a data voltage from the drain electrode 175. The pixel electrode 191 to which the data voltage is applied has a liquid crystal between the two electrodes by generating an electric field together with a common electrode (not shown) of another display panel (not shown) to which a common voltage is applied. The direction of the liquid crystal molecules in the layer (not shown) is determined. The polarization of light passing through the liquid crystal layer varies according to the direction of the liquid crystal molecules determined as described above. The pixel electrode 191 and the common electrode form a liquid crystal capacitor to maintain an applied voltage even after the thin film transistor is turned off.

The pixel electrode 191 overlaps the storage electrode lines 131 including the storage electrodes 133a and 133b to form a storage capacitor that strengthens the voltage holding capability of the liquid crystal capacitor.

The pixel electrode 191 also overlaps the neighboring gate line 121 to increase the aperture ratio, but may not overlap.

The contact auxiliary members 81, 82, 86, and 87 each have an end portion 129 of the gate line 121 and an end portion 126 of the temperature sensing line 125 through the contact holes 181, 182, 186, and 187, respectively. 127 and an end portion 179 of the data line 171. The contact auxiliary members 81, 82, 86, and 87 may include an end portion 129 of the gate line 121, an end portion 126 and 127 of the temperature sensing line 125, and an end portion 179 of the data line 171. ) And protects them from adhesion to external devices.

The connecting leg 83 crosses the gate line 121 and exposes the exposed portion of the storage electrode line 131 and the storage electrode through contact holes 183a and 183b positioned on opposite sides with the gate line 121 interposed therebetween. 133b) is connected to the exposed end of the free end. The storage electrode lines 131 including the storage electrodes 133a and 133b may be used together with the connecting legs 83 to repair defects in the gate line 121, the data line 171, or the thin film transistor.

As described above, since the temperature sensing line 125 formed together with the gate line 121 acts as a resistance and the resistance value changes according to the temperature, the temperature sensing line 125 functions as a temperature sensor 51.

The area occupied by the temperature sensing line 125 may be approximately 2 mm × 2 mm in width and width.

Since the temperature sensor 51 is made together with the metal wiring such as the gate line 121 having excellent stability of the surface formed by the stuttering, malfunctions caused by damage to the surface of the temperature sensor 51 due to external impact or Breakage is reduced.

Next, the temperature sensor illustrated in FIGS. 4 to 7 is shown as an equivalent circuit, and will be described in detail with reference to FIG. 8.

8 is an equivalent circuit diagram of a temperature sensor according to an embodiment of the present invention.

As shown in FIG. 8, the temperature sensor 51 may be represented by a resistor Rs connected to the driving voltage Vdd, and the resistor Rc is connected between the temperature sensor 51 and the ground. The resistor Rc is a constant resistor having a constant resistance value.

The temperature sensor 51 receives the voltage Vdd at the end 126 of the temperature sensing line 125, and outputs the output signal Vout to the other end 127 connected to the resistor Rc. Output as Vs).

The output signal Vout is obtained as shown in Equation 1 below.

이고,Where Rs is

ego,

이다. ρ is

to be.

Where ρ is the resistivity of the temperature sensing line 125, W is the width of the temperature sensing line 125, L is the length of the temperature sensing line 125, and D is the temperature sensing. The thickness of line 125. Ρ _o is the specific resistance at a specific temperature, for example about 20 ° C., α is the temperature coefficient of resistance (TCR), i.e., the coefficient representing the change in resistance to temperature changes, and T is the temperature .

Here, the specific resistance (ρ _o ) and the temperature coefficient (α) at a specific temperature according to each material are constants already determined, and the width (W), length (L) and thickness (D) of the temperature sensing line 125 are defined. Is determined at design time.

As a result, since the value of the resistance Rs which is the temperature sensor 51 changes with temperature T, the output voltage Vout becomes a value which changes with temperature T. As shown in FIG.

As already explained, since the width, length and thickness of the temperature sensing line 125 are determined at the time of designing the temperature sensor 51, the characteristics of the temperature sensor 51 are determined by them.

Specific resistivity (ρ _o ) and temperature coefficients of aluminum (Al), copper (Cu), platinum (Pt), chromium (Cr) and molybdenum (M0), which are some of the materials that can be used to make the temperature sensing line 125 (alpha) is illustrated in [Table 1].

material Ρ _o (10 ^-8 Ωcm) at 20 ℃ Temperature coefficient (α) (10 ^-4 / k) Aluminum (Al) 2.69 42.0 Copper (Cu) 1.67 43.0 Platinum (Pt) 10.6 39.2 Chrome (Cr) 12.1 ? Molybdenum (Mo) 5 ?

At this time, in order to improve the sensitivity of the temperature sensor 51 and to perform a stable sensing operation, it is preferable that the temperature coefficient α is larger and the same value is measured every time. It is preferable that the value of (ρ) is made of a metal that changes linearly.

 At this time, in order to improve the sensitivity of the temperature sensor 51 and to perform a stable sensing operation, the larger the temperature coefficient α is, the better it is to have the same value every time the measurement is performed. It is preferable to design the temperature sensor 51 using a metal that changes linearly.

Next, referring to FIG. 9, when the temperature sensor 51 is manufactured using the temperature sensing line 125 illustrated in FIGS. 4 to 7, the change in the output voltage Vout of the temperature sensor 51 according to the temperature change is performed. Let's look at it.

9 is a graph illustrating voltage characteristics according to temperature changes output from a temperature sensor according to an exemplary embodiment of the present invention.

In FIG. 9, the experimental temperature sensing line 125 has a double layer structure including an aluminum (Al) lower layer and a molybdenum (Mo) upper layer. The driving voltage Vdd is about 2V, and the resistance Rc is about 1.7. It was ㏀.

As can be seen in FIG. 9, in the range of about −10 to 80 ° C., the output voltage Vout changed very linearly with temperature change. At this time, the sensitivity of the produced temperature sensor 51 was about 1.83 (㎷ / 占 폚), and the signal output from the sensor could be directly used without signal conversion using a separate amplification circuit or the like.

The temperature sensing line 125 may be made of the same layer as the data line 171 or the pixel electrode 191. In this case, the temperature sensing line 125 may have a triple layer of a molybdenum (alloy) lower layer, an aluminum (alloy) interlayer, and a molybdenum (alloy) upper layer. However, the metal used for the temperature sensing line 12 has a larger temperature coefficient α and has the same value every time of measurement, and if the value of the specific resistance ρ varies linearly with the change in temperature T, whatever All are available.

The operation of the liquid crystal display device will now be described in detail.

The signal controller 600 receives an input control signal for controlling the display of the input image signals R, G, and B from an external graphic controller (not shown). Examples of the input control signal include a vertical synchronization signal Vsync, a horizontal synchronization signal Hsync, a main clock MCLK, and a data enable signal DE. In addition, the signal controller 600 receives the temperature detection signal Vs from the temperature sensor unit 50.

The signal controller 600 properly processes the input image signals R, G, and B based on the input image signals R, G, and B and the input control signal, according to operating conditions of the liquid crystal panel assembly 300, and controls the gate. After generating the signal CONT1 and the data control signal CONT2, the gate control signal CONT1 is sent to the gate driver 400, and the data control signal CONT2 and the processed image signal DAT are transmitted to the data driver 500. Export to). In this case, the signal controller 600 controls the operation of the gate driver 400 or the data driver 500 based on the temperature sensing signal Vs, and the operation of the signal controller 600 will be described in detail below. .

The gate control signal CONT1 includes at least one clock signal for controlling the output period of the scan start signal STV indicating the start of scanning and the gate-on voltage Von. The gate control signal CONT1 may also further include an output enable signal OE that defines the duration of the gate-on voltage Von.

The data control signal CONT2 is a load signal LOAD for applying a data signal to the horizontal synchronization start signal STH indicating the start of the transmission of the image signal for one row of pixels PX and the data lines D ₁ -D _m . ) And a data clock signal HCLK. The data control signal CONT2 is also an inverted signal that inverts the voltage polarity of the data signal relative to the common voltage Vcom (hereinafter referred to as " polarity of the data signal " by reducing the " voltage polarity of the data signal for the common voltage ") RVS) may be further included.

According to the data control signal CONT2 from the signal controller 600, the data driver 500 receives the digital image signal DAT for the pixel PX in one row and corresponds to each digital image signal DAT. The gradation voltage is selected to convert the digital image signal DAT into an analog data signal and then apply it to the data lines D ₁ -D _m .

The gate driver 400 applies the gate-on voltage Von to the gate lines G ₁ -G _n in response to the gate control signal CONT1 from the signal controller 600, thereby applying the gate lines G ₁ -G _n . Turn on the switching element (Q) connected to. Then, the data signal applied to the data lines D ₁ -D _m is applied to the pixel PX through the turned-on switching element Q.

The difference between the voltage of the data signal applied to the pixel PX and the common voltage Vcom is represented as the charging voltage of the liquid crystal capacitor C _LC , that is, the pixel voltage. The arrangement of the liquid crystal molecules varies depending on the magnitude of the pixel voltage, thereby changing the polarization of light passing through the liquid crystal layer 3. The change in polarization is represented by a change in transmittance of light by a polarizer attached to the display panel assembly 300.

This process is repeated in units of one horizontal period (also referred to as "1H" and equal to one period of the horizontal sync signal Hsync and the data enable signal DE), thereby all the gate lines G ₁ -G _n. ), The gate-on voltage Von is sequentially applied to the data signal to all the pixels PX, thereby displaying an image of one frame.

When one frame ends, the state of the inversion signal RVS applied to the data driver 500 is controlled so that the next frame starts and the polarity of the data signal applied to each pixel PX is opposite to the polarity of the previous frame. "Invert frame"). In this case, the polarity of the data signal flowing through one data line is changed (eg, row inversion and point inversion) or the polarity of the data signal applied to one pixel row is different depending on the characteristics of the inversion signal RVS within one frame. (E.g. column inversion, point inversion).

As described above, since the operating characteristics of the liquid crystal, circuit elements, and the like change according to the temperature of the liquid crystal display device, a compensation operation considering temperature is required, and during such a correction operation, the DCC (dynamic capacitance compensation) or the gate-on voltage Resizing and so on.

In more detail, since the characteristics of the liquid crystal change according to temperature, and thus the response time of the liquid crystal is also changed, the signal controller 600 controls the temperature detection signal Vs during DCC control to improve the response time of the liquid crystal. DCC is performed in consideration of the temperature determined by.

In addition, the threshold voltage of the switching element Q, which is a thin film transistor, changes with temperature. Therefore, the signal controller 600 changes the size of the reference voltage for generating the gate-on voltage Von according to the temperature, and adjusts the size of the gate-on voltage Von, thereby changing the switching element Q according to the temperature. To compensate for the turn-on time.

During the temperature compensation operation, DCC by the signal controller 600 will be described with reference to FIG. 10.

10 is a block diagram of a signal controller according to another embodiment of the present invention.

As shown in FIG. 10, the signal controller 600 includes a frame memory 611 to which an image signal of one frame (hereinafter referred to as a current image signal) G _n is applied to a certain pixel. The signal output unit 613 is connected to the table unit 612, the frame memory 611, and the lookup table unit 612 and to which the temperature sensing signal Vs and the current image signal G _n are applied. All or part of them may be mounted outside the signal controller 600.

The frame memory 611 transmits an image signal (referred to as a previous image signal) (G _n-1 ) of a previous frame for an arbitrary pixel to the lookup table unit 612 and the signal output unit 613. It supplies and stores the current video signal G _n from the outside.

The lookup table unit 612 includes a plurality of lookup tables LU1-LUp. Each look-up table (LU1-LUp), the temperature sensor portion has a plurality of the corrected video signal, respectively, the value determined on the basis of the temperature detection signal (Vs) from the 50 previous image signal (G _n-1) and the current image signal ( G _n ) is stored as a function. In this case, the corrected image signal is determined by an experiment result considering the temperature of the liquid crystal panel assembly and the difference between the current image signal and the previous image signal. As already explained, the difference between the corrected video signal and the previous video signal is generally larger than the difference between the current video signal before the correction and the previous video signal.

The operation of the signal controller 600 will be described.

First, the signal output unit 613 determines the detected temperature based on the temperature detection signal Vs from the temperature sensor unit 50, and determines one of the plurality of lookup tables LU1-LUp according to the determined temperature. Select a lookup table. For example, the signal output unit 613 selects the first lookup table LU1 if the determined temperature range belongs to the first range, and selects the pth lookup table LUp if it belongs to the p range. Can be.

Next, the signal output unit 613 selects the corrected video signal based on the current video signal G _n from the outside and the previous video signal G _n-1 from the frame memory 611 in the selected lookup table. It is applied to the data driver 500 as an image signal DAT.

As a result, the voltage of the data signal applied to each pixel by the data driver 500 becomes higher or lower than the target data voltage, thereby reducing the arrival time to the desired pixel voltage.

As in the present embodiment, instead of storing both the previous video signal G _n-1 and the corrected video signal for each current video signal G _n in the lookup table, a predetermined number of previous video signals having a predetermined interval ( Only a corrected video signal (hereinafter referred to as a reference corrected video signal) for a predetermined number of current video signals (hereinafter referred to as a reference current video signal) corresponding thereto is stored in the lookup table. In this case, the interval between the reference previous video signal and the reference current video signal may or may not be kept constant. The remaining corrected video signal is calculated by interpolation using the reference previous video signal and the reference current video signal. In this case, the size of the lookup table is reduced.

In addition, the temperature sensor according to the present embodiment is not only a liquid crystal display device for sensing the temperature of the liquid crystal layer, but also a plasma display panel (PDP) or an organic light emitting display device (PDP) whose operating characteristics change depending on the temperature. It is also applicable to other display devices such as OLED).

As such, since the temperature sensor 51 is manufactured using only metals without using a semiconductor having a high photoreactivity, the temperature sensor 51 is not affected by light applied from the outside, thereby achieving stable temperature sensing. In addition, since it is not necessary to form a separate shielding film for blocking incident light, the manufacturing process and structure is simple.

In addition, since the temperature sensor is made together with the gate line and the data line and embedded directly in the liquid crystal panel assembly, the sensed temperature is almost similar to the temperature of the liquid crystal layer.

As such, since a temperature sensor for sensing the temperature of the liquid crystal display device is directly embedded in the liquid crystal display device, a temperature close to the temperature of the liquid crystal layer adjacent to the outside is sensed without greatly increasing the manufacturing cost.

As a result, since the image signal applied to the pixel is corrected based on the sensing temperature approximating the temperature around the liquid crystal layer, the response speed of the liquid crystal can be efficiently improved by correcting the image signal suitable for the characteristic of the liquid crystal which varies with temperature. Accordingly, the image quality of the display device is also improved. In addition, since the temperature sensor is directly embedded in the liquid crystal panel assembly, the space limitation for mounting a separate temperature sensor on a printed circuit board is eliminated, and the cost of separately purchasing the temperature sensor is reduced.

Furthermore, since the temperature sensor is manufactured using only metals that are not sensitive to light, malfunctions due to light from the outside are eliminated, and a separate structure for shielding the incoming light is not required. Or the structure is simple.

In addition, since the temperature sensor is made together with the metal wiring having excellent surface stability, malfunctions or breakages caused by damage to the surface of the temperature sensor due to external shock are reduced.

In addition, since the signal output from the temperature sensor can be used directly without separately amplifying, an additional circuit such as an amplifying circuit is not required.

In the above, preferred embodiments of the present invention have been described in detail, but the scope of the present invention is not limited thereto, and various modifications and improvements of those skilled in the art using the basic concepts of the present invention defined in the following claims are also provided. It belongs to the scope of the invention.

Claims (34)

Substrates for display devices, and A temperature sensing line formed on the substrate / RTI > The temperature sensing line is a conductor, The display device, A gate line formed on the substrate, A first insulating film formed on the gate line, A data line formed on the first insulating film, and A second insulating film formed on the data line / RTI > The temperature sensing line is formed on the same layer as any one of the gate line and the data line. Temperature sensor for display device. In claim 1, And said temperature sensing line meanders. In claim 1, The temperature sensing line includes a lower layer made of aluminum (Al) or an aluminum alloy and an upper layer made of molybdenum (Mo) or molybdenum alloy. In claim 1, The temperature sensing line is one of aluminum, copper (Cu), platinum (Pt), chromium (Cr) and molybdenum. In claim 1, Further comprising an insulating film formed on the temperature sensing line, The insulating layer has first and second contact holes exposing both ends of the temperature sensing line. Temperature sensor for display device. The method of claim 5, And a contact auxiliary member connected to an end portion of the temperature sensing line through the first and second contact holes. In claim 6, And the contact assistant member is made of ITO or IZO. In claim 1, The specific resistance of the temperature sensing line changes linearly with temperature change. delete delete delete In claim 1, The data line includes a lower film made of molybdenum or molybdenum alloy, an intermediate film made of aluminum or aluminum alloy, and an upper film made of molybdenum or molybdenum alloy. In claim 1, And the first or second insulating layer has first and second contact holes that expose both ends of the temperature sensing line, respectively. The method of claim 13, The display device further includes a contact auxiliary member connected to an end of the temperature sensing line through the first and second contact holes. The method of claim 14, And the contact assistant member is made of ITO or IZO. The method according to any one of claims 1 to 8 and 12 to 15, And said display device is a liquid crystal display device. Board, A gate line formed on the substrate, A first insulating film formed on the gate line, A data line formed on the first insulating film, A second insulating film formed on the data line, and A temperature sensing line formed on the substrate / RTI > The temperature sensing line is formed on the same layer as any one of the gate line and the data line. Thin film transistor display panel. The method of claim 17, The thin film transistor array panel which meanders the temperature sensing line. The method of claim 17, The temperature sensing line includes a lower layer made of aluminum (Al) or an aluminum alloy and an upper layer made of molybdenum (Mo) or molybdenum alloy. The method of claim 17, The temperature sensing line is formed of one of aluminum, copper (Cu), platinum (Pt), chromium (Cr), and molybdenum. The method of claim 17, The temperature sensing line includes a lower film made of molybdenum or molybdenum alloy, an intermediate film made of aluminum or aluminum alloy, and an upper film made of molybdenum or molybdenum alloy. The method of claim 17, The resistivity of the temperature sensing line changes linearly with temperature. The method of claim 17, And a pixel electrode formed on the substrate and connected to the thin film transistor connected to the gate line and the data line. The method of claim 23, The pixel electrode is made of ITO or IZO. delete delete The method of claim 23, And the second insulating film has a first contact hole exposing a part of the drain electrode of the thin film transistor. The method of claim 27, The thin film transistor array panel of claim 1, wherein the first insulating film or the second insulating film has second and third contact holes that expose both ends of the temperature sensing line, respectively. The method of claim 28, And a contact auxiliary member connected to both ends of the temperature sensing line through the second and third contact holes, respectively. The method of claim 29, And the contact assistant member is formed on the same layer as the pixel electrode. A plurality of pixels, A first signal line connected to the pixel, and A second signal line connected to the pixel and intersecting the first signal line, and A temperature sensing line spaced apart from the first and second signal lines / RTI > The temperature sensing line is formed on the same layer as the first or second signal line. Liquid crystal display. The method of claim 31, And a signal controller which controls the display of the pixel based on the signal from the temperature sensing line. 33. The method of claim 32, The liquid crystal display further comprises a data driver converting the corrected image signal from the signal controller into a data signal and applying the gate signal to the second signal line to control the operation of the pixel. . The method of claim 33, The signal control unit receives an image signal from the outside and outputs the corrected image signal correcting the image signal based on a previous image signal. And the correction of the image signal depends on the signal from the temperature sensing line.

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