KR20100008126A - Aging apparatus and methode of mother plate with organic light emitting display panels - Google Patents

Abstract

PURPOSE: An aging apparatus of a mother plate with organic light emitting display panels and a method thereof are provided to reduce aging time by obtaining aging effect with low current. CONSTITUTION: A motherboard is placed on a base plate(20). A heater(40) is coupled with the base plate and supplies heat to the mother board. A signal supply part(30) applies aging signals to a pixel of each panel and emits the light. A sensor(50) is coupled on the base plate and detects the temperature of the base plate. A controller(80) controls the heater based on the temperature information transferred to the sensor. The vacuum pad closely attaches the motherboard to the single-side of the base plate.

Description

Aging apparatus and method of mother plate with organic light emitting display panels

The present invention relates to an aging apparatus and method of a mother substrate for performing an electrical aging test while applying heat to a mother substrate on which a plurality of organic light emitting display panels are formed.

The organic light emitting display device is a next-generation display device having self-luminous characteristics. The organic light emitting display device maintains the same color reproducibility even with a change in brightness, has a fast response speed, a wide viewing angle, and a liquid crystal display device. It has the advantage of being thinner than device (LCD).

The organic light emitting display device has a passive matrix method including a plurality of pixels connected in a matrix manner between a scan line and a signal line, and a thin film trasistor serving as a switch. TFTs may be classified into an active matrix method in which the operation of each pixel is controlled.

The organic light emitting device constituting the pixel includes an anode electrode, an organic thin film layer, and a cathode electrode, and when a predetermined voltage is applied to the anode electrode and the cathode electrode, electrons injected through the hole and the cathode electrode injected through the anode electrode emit light. Recombine at, and emit light due to the energy difference in the process.

In order to more efficiently produce the organic light emitting display, panels of a plurality of organic light emitting display are generally formed on one mother substrate and then cut and manufactured into individual panels. The production method using the mother board is called the production method of the sheet unit.

On the other hand, the organic light emitting device has a property that deterioration proceeds rapidly at the initial stage of driving and then stabilizes. Therefore, the organic light emitting display device undergoes an aging test before shipment of the product in order to prevent a significant deterioration in quality or reliability immediately after the shipment.

The aging test is to deteriorate to some extent by driving the organic light emitting device for a predetermined time. In the aging test, the panel is supplied with driving powers and / or driving signals. The driving power sources and / or the driving signals become aging signals. The aging signal includes a voltage or a current supplied to a data line of each pixel so that a predetermined current flows in the organic light emitting display.

In order to reduce the aging test time of the organic light emitting display panel, the amount of current flowing through the panel per unit time must be increased. However, the maximum aging current that can be applied to the organic light emitting display panel is already determined by the wiring material provided in the manufactured panel, the short area of the wiring, and the like. Due to the limited aging current that can be applied to the panel, it is difficult to shorten the working time of the aging test.

In particular, when the aging test is performed on a plurality of organic light emitting display panels on the mother substrate in a room temperature atmosphere, a large amount of current flows to the mother substrate because an aging signal is simultaneously supplied to the plurality of panels. The heat generation problem occurs in the wiring. As described above, in the aging test of the mother substrate, there is a problem that the aging current that can be applied to the mother substrate is further limited due to the heat generation of the wiring, thereby aging time becomes longer.

An object of the present invention is to provide an aging apparatus capable of aging test a mother substrate on which a plurality of organic light emitting display panels are formed in a short time.

Another object of the present invention is to provide an aging method which can shorten an aging time when an aging test of a mother substrate on which a plurality of organic light emitting display panels is formed.

According to an aspect of the present invention for solving the above problems, an aging apparatus for a mother substrate for aging test the mother substrate in which the plurality of organic light emitting display panels are arranged in a ledger unit, the base plate on which the mother substrate; A heater coupled to the base plate and supplying heat to the mother substrate; And a signal supply unit which emits light by applying an aging signal to the pixels of each panel.

Preferably, the mother substrate aging device comprises a sensor coupled to the base plate and detecting the temperature of the base plate; And a controller for controlling the heater based on the temperature information transmitted from the sensor.

The controller may control the heater to maintain the temperature of each organic light emitting display panel in a range of 70 ° C. or higher and less than 80 ° C.

The mother substrate aging apparatus may further include a vacuum pad penetrating the base plate in a thickness direction to be exposed to one surface of the base plate and closely contacting the mother substrate to one surface of the base plate.

The mother substrate aging apparatus may further include a plurality of auxiliary sensors distributedly installed on the base plate to monitor temperatures of respective portions of the base plate.

The mother substrate aging apparatus may further include a driving unit coupled to one surface of the base plate and moving the base plate up and down.

The signal supply unit has a built-in control program for driving each panel, and can display the aging check status of each panel for the aging test.

The pixel power source may be individually applied to the organic light emitting display panels arranged in at least one row direction or column direction of the mother substrate.

According to another aspect of the invention, the step of placing a mother substrate on which the plurality of organic light emitting display panel is formed on the base plate; Supplying heat to the base plate through a heater coupled to the base plate; And supplying an aging signal to each organic light emitting display panel.

Preferably, the aging method of the mother substrate comprises the steps of sensing the temperature of the mother substrate through a sensor coupled to the base plate; And controlling the heater in a controller coupled to the sensor and the heater so that the temperature of the mother substrate is maintained within a set temperature range. Here, the set temperature range is 70 degreeC or more and less than 80 degreeC.

The aging method of the mother substrate may further include the step of bringing the mother substrate into close contact with one surface of the base plate with a vacuum pad coupled to the base plate.

The aging method of the mother substrate may further include monitoring the temperatures of each part of the base plate through a plurality of auxiliary sensors distributed in the base plate.

The supplying an aging signal may include separately supplying an aging signal to the organic light emitting display panels arranged in at least one row direction or column direction on the mother substrate.

According to the aging apparatus and method of the mother substrate of this embodiment, the aging time can be shortened while applying an aging signal within a range that does not cause a problem in the wiring heat generation of the mother substrate on which the plurality of organic light emitting display panels are formed. That is, the same aging effect can be obtained with a small current, and the aging time can be shortened while using a limited aging current.

In addition, by compensating for the voltage drop applied to each panel, it is possible to shorten the aging time by increasing the aging current while preventing driving failure and bright spots of each panel.

Hereinafter, exemplary 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 implement the present invention. As those skilled in the art would realize, the described embodiments may be modified in various different ways, all without departing from the spirit or scope of the present invention.

1 is a block diagram of an aging apparatus of a mother substrate according to an embodiment of the present invention.

In the aging apparatus of the present embodiment, when aging a mother substrate on which a plurality of organic light emitting display panels are formed, an electrical aging test is performed while directly heating the mother substrate to reduce the aging process time to approximately 30 minutes. It is a main technical characteristic to do. Here, the electrical aging test refers to deterioration to some extent by driving the organic electroluminescent device for a predetermined time before shipping the panel in order to increase the stability and reliability of the organic electroluminescent device.

Referring to FIG. 1, the aging apparatus of the present embodiment includes a base plate 20, a signal supply unit 30, a heater 40, a main sensor 50, a vacuum pad 60, a driver 70, and a controller 80. It includes. The controller 80 controls the signal supply unit 30, the heater 40, the main sensor 50, the vacuum pad 60, and the driver 70 coupled to the base plate 20, respectively.

In the aging apparatus of the present embodiment, when the mother substrate 100 is placed on one surface of the base plate 20 for an aging test, the mother substrate 100 is closely attached to one surface of the base plate 20 using the vacuum pad 60. Then, the position of the base plate 20 is adjusted to a desired height by using the driving unit 70. The base plate 20 is heated by the heater 40, thereby raising the temperature of the mother substrate 100 in close contact with one surface of the base plate 20.

In addition, the aging device detects the temperature of the mother substrate 100 through the main sensor 50, the temperature of the mother substrate 100 reaches a certain temperature, for example, any temperature within the range of more than 70 ℃ to less than 80 ℃. An aging test is performed by applying an aging signal to each organic light emitting display panel of the mother substrate 100 through the signal supply unit 30. Here, the temperature range of more than 70 ℃ to less than 80 ℃ is a temperature for preventing this because it is easily damaged at a temperature of more than 80 ℃ due to the characteristics of the organic light emitting device including an organic light emitting layer, the heater 40 at a temperature of less than 80 ℃ B) an error value of the main sensor 50 or the like, for example, about ± 5 ° C.

On the other hand, the aging device of the present embodiment, in the aspect of performing an aging test by supplying an aging signal while applying heat to the mother substrate 100, the control unit 80 after the temperature of the mother substrate reaches a certain temperature aging signal It may be designed to apply the aging signal first even before applying or even before the temperature of the mother substrate 100 reaches a certain temperature. In both cases described above, the effect of shortening the aging time can be obtained, of course.

The signal supply unit 30 has a built-in control program for driving each panel formed on the mother substrate 20. The signal supply unit 30 supplies the pixel power, the scan signal, and the aging signal to each panel to perform an electrical aging test. It is configured to display the aging check status of each panel for the test. The aging signal includes a voltage or current applied to the data line of each panel so that a predetermined voltage is supplied between the anode and the cathode of the organic light emitting diode to emit the organic light emitting diode.

In particular, when the temperature of the mother substrate 100 is raised to a temperature of about 75 ℃ significantly higher than room temperature, the signal supply unit 30 of the present embodiment is designed to apply the aging signal to the mother substrate 100, the aging test time This can be greatly reduced from about 5 hours to about 30 minutes. At this time, the strength of the current supplied to the panel during the aging test has the strength of the current that does not cause a problem due to the wiring heating.

The current that can flow through the wiring varies depending on the material and thickness of the wiring, but is roughly reduced due to the increase in resistance when the temperature of the wiring rises. Therefore, the strength of the current that can be applied to the mother substrate 100 in the aging test decreases as the temperature of the mother substrate 100 increases when the temperature of the mother substrate 100 rises from room temperature to less than about 80 ° C. do. The intensity of the aging current of the present embodiment is smaller than the intensity of the aging current in the conventional case of performing the aging test while maintaining the temperature of the mother substrate near room temperature through a heat sink device.

For reference, in some existing aging test processes, the cooling plate of the base plate is normally mounted due to the heat generation of the mother substrate, and the base plate is cooled by using a fan. Prevented enough. Nevertheless, in the existing aging test process, there is a problem that the aging test process time is still long because the current that can be applied to the mother substrate is limited by the wiring structure. For example, the conventional aging test process performed on the mother substrate without cutting the plurality of organic light emitting display panels produced in the ledger unit on one mother substrate took about 5 hours. Therefore, the existing aging test process is difficult to reduce the efficiency of the manufacturing process of the organic light emitting display panel, it is difficult to apply to the mass production process. However, by using the aging apparatus of the present embodiment described above, it is possible to achieve the same aging effect in a short time compared to the existing aging apparatus while using a small amount of aging current. An example of the aging device of this embodiment will be described in more detail below.

FIG. 2 is a plan view specifically showing an example of the aging apparatus described above with reference to FIG. 1. 3 is a schematic front view of the aging device of FIG. 2. In FIG. 3, all of the same elements illustrated in FIG. 2 are not illustrated and all of the overlapping elements are omitted for convenience of illustration. For convenience, some elements are indicated by dotted lines to schematically show the coupling relationship.

2 and 3, the aging apparatus 10 of the present embodiment includes a base plate 20, a signal supply unit, four heaters 40, one main sensor 50, and ten auxiliary sensors 52. ), Six vacuum pads 60, a drive unit 70 having four shafts, and a control unit. 2 and 3, the control unit and the signal supply unit of the present embodiment are omitted for convenience, and correspond to the control unit and the signal supply unit of FIG.

The base plate 20 is made of a material capable of supporting a mother substrate on which a plurality of organic light emitting display panels are formed, and effectively transferring heat to the mother substrate on one surface thereof. For example, the base plate 20 may be made of a plate-shaped aluminum material having a thickness of 20 mm. The thickness of the base plate 20 may be adjusted according to the size of the mother substrate.

The heater 40 is coupled to the base plate 20 to enable heat transfer. In the present embodiment, four heaters 40 are respectively inserted into four drainage-shaped trenches 23 formed in the base plate 20. Four heaters 40 are installed to effectively raise the temperature of the entire mother substrate uniformly and in a short time, the number can be adjusted according to the size of the base plate 20 or the type and size of the heater 40. have.

For example, each heater 40 may be implemented as an electric heater, the heating wire portion 42 is inserted into the trench 23 formed on one surface of the base plate 20, and supplies the heating wire portion 42 The wire 44 may be electrically connected to the device. In addition, each heater 40 may be fixedly coupled to the base plate 20 through a predetermined physical fixing means and fixing method. Here, one surface of the base plate 20 refers to a surface on which the leg portion 24 of the base plate 20 is installed. And the physical fastening means comprise a bolt and nut structure.

The main sensor 50 detects the temperature of the base plate 20. The temperature information detected by the main sensor 50 is used by the controller 80 to control the heater 40 so that the temperature of the mother substrate does not rise above a predetermined temperature. In the present embodiment, the main sensor 50 is installed at approximately the center of the base plate 20. The main sensor 50 is a thermistor whose resistance changes with temperature, a resistance temperature detector (RTD), which is a wire that changes resistance with temperature, and a combination of two different metals. It may be implemented as a thermocouple (thermocouple), a semiconductor temperature sensor, and the like.

The auxiliary sensor 52 is installed in the base plate 20 to monitor the temperature of each corresponding region of the base plate 20 adjacent to each organic light emitting display panel of the mother substrate. Ten auxiliary sensors 52 of the present exemplary embodiment are substantially uniformly distributed on one surface of the base plate 20. The auxiliary sensors 52 may be implemented with the same sensor as the main sensor 50.

Using the auxiliary sensors 52, it is possible to individually measure or estimate the temperature of the plurality of organic light emitting display panels of the mother substrate. Therefore, it is possible to monitor and control how uniformly the aging test is performed on each organic light emitting display panel of the mother substrate.

The vacuum pad 60 is installed to bring the mother substrate into close contact with one surface of the base plate 20 which is heated to a predetermined temperature by the heater 40. The temperature of the mother substrate in close contact with the base plate 20 can be effectively increased by the heater 40 installed in the base plate 20. One end of the vacuum pad 60 passes through the base plate 20 in the thickness direction and is exposed to the upper surface of the base plate 20. The upper surface is a surface facing one surface of the base plate 20 to which the legs 24 are coupled.

The vacuum pad 60 may be implemented as a vacuum generator or a ejector-type vacuum generator (not shown). Ejector type vacuum generator is a device for making a vacuum directly from the compressed air, and basically comprises a nozzle (nozzle) for injecting high speed air and a diffuser (diffuser) to which the air injected from the nozzle is introduced. The nozzle and the diffuser are installed to face each other at a predetermined distance. The gap between the nozzle and the diffuser produces a negative pressure according to Bernoulli's theorem, which becomes a vacuum. This negative pressure causes the air around the gap to be drawn into the diffuser by the viscosity of the air. The aforementioned gap is connected in fluid communication with the vacuum pad 60. Compressed air injected from the nozzle and air sucked into the vacuum pad 60 are discharged to the exhaust port through the diffuser.

The driving unit 70 is a device for moving the base plate 20 in the vertical direction. In this embodiment, the driving unit 70 has four shafts coupled to one surface of the base plate 20. Each shaft is coupled to the driving unit main body (not shown) and performs a linear reciprocating motion in the vertical direction by the driving force of the main body. When the base plate 20 does not need to move in the vertical direction, the driving unit 70 may be omitted in the aging apparatus according to the present embodiment.

The controller 80 may control the main sensor 50 and / or the auxiliary sensors 52 such that the temperature of the base plate 20, the temperature of the mother substrate, or the temperature of each organic light emitting display panel does not rise above a predetermined temperature. The operation of the heater 40 is controlled based on the sensed temperature information. In addition, the controller 80 may control the vacuum generator and the driver 70 to which the vacuum pad 60 is coupled.

The controller 80 may include a control device for controlling the signal supply unit 30 or may be implemented as some functions of the control device. In other words, the controller 80 may be configured as a separate module for supplying heat to the mother substrate during the electrical aging test of the signal supply unit 30 together with the heater 40, the sensor 50, and the vacuum pad 60. . On the other hand, the controller 80 may be configured to control all elements of the aging apparatus so that the aging apparatus of the present embodiment can perform an aging test on the mother substrate as the control device of the signal supply unit 30. The controller 80 may be implemented as at least some functions of a logic circuit or a microcontroller using a flip-flop.

4 is a plan view of an example of a mother substrate on which an aging test is performed by the aging apparatus of this embodiment.

The mother substrate as an example in this embodiment is manufactured by the present applicant. When the aging signal is supplied to the mother substrate 100 while applying heat to the mother substrate, the mother substrate 100 can be almost uniformly supplied to each organic light emitting display panel.

For reference, in the aging test of the ledger unit, since the required current value is high, a voltage drop may occur in the ledger wiring that supplies the driving power and / or the driving signal to each panel. In particular, since the aging voltage is continuously applied during the aging test operation in the ledger wiring which transfers the DC power as the pixel power, the voltage drop may be larger than other driving signals or the reference power supply voltage applied only for a predetermined time. It may cause a problem that the reliability of the aging test is deteriorated for some panels by causing the pixel power sources having different voltage levels to be supplied to each panel.

However, according to the aging apparatus and method of the present embodiment using the mother substrate 100 to be described later, the aging test of the ledger unit can be efficiently performed without cutting the plurality of organic light emitting display panels produced in the ledger unit. In addition, the aging time can be greatly reduced.

Referring to FIG. 4, the mother substrate 100 applied to the present embodiment is formed in a plurality of organic light emitting display panels 110 arranged in a matrix type in a first direction in an outer region of the panels 110. It includes a first wiring group 120 and a second wiring group 130 formed in a second direction.

Each panel 110 includes a scan driver 140, a pixel unit 150, a first inspection unit 160, a data distribution unit 170, a second inspection unit 180, and a pad unit 190.

The scan driver 140 generates a scan signal and / or a light emission control signal in response to the first and second reference power supply voltages and the scan control signal supplied from the outside, and then scan the scan lines S1 to Sn and / or emit light. The control lines E1 to En are sequentially supplied. In this case, the high level voltage of the scan signal and / or the emission control signal generated by the scan driver 140 is set to the first reference power supply voltage, that is, the gate high level voltage VGH. The low level voltage of the scan signal and / or the light emission control signal is set to the second reference power supply voltage, that is, the gate low level voltage VGL.

The pixel unit 150 includes a plurality of pixels (not shown) positioned at intersections of the data lines D1 to D3m, the scan lines S1 to Sn, and the emission control lines E1 to En. Each pixel includes an organic light emitting diode and transistors for driving the same.

The first inspection unit 160 is electrically connected to one side ends of the data lines D1 to D3m through the data distribution unit 170. The first inspection unit 160 is provided for an array inspection (first inspection) for inspecting a connection state of transistors or wires formed in the panel 110. The first inspection unit 160 receives an array inspection signal (first inspection signal) from an external array inspection apparatus (not shown) while the array inspection is in progress and outputs them to the output lines O1 to Om.

The data distribution unit 170 is connected between the first inspection unit 160 and the pixel unit 150. The data distribution unit 170 may receive an array inspection signal supplied from the output lines O1 to Om of the first inspection unit 160 in response to a clock signal (for example, red, green and blue clock signals) supplied from the outside. Supply to the data lines D1 to D3m. For example, when one pixel is composed of three subpixels, that is, red, green, and blue subpixels, the data distributor 170 may output an array inspection signal supplied from the first inspector 160 to the red, green, and blue pixels. It is supplied to three data lines D of each of the blue subpixels.

Meanwhile, after the inspection of the panels 110 is completed and each of the panels 110 is scribed from the mother substrate 100, the data distribution unit 170 output lines of the data driver (not shown). The data signal supplied from the second pixel is supplied to the data line D of each subpixel.

The second inspection unit 180 is electrically connected to the other end of the data lines D1 to D3m. That is, the first inspection unit 160 and the second inspection unit 180 are connected to different ends of the data lines D1 to D3m, and they are disposed to face each other with the pixel unit 150 therebetween. The second inspection unit 180 is provided for a ledger inspection (second inspection) that allows a plurality of organic light emitting display panels 110 formed on the mother substrate 100 to be inspected at one time in a ledger unit. . Ledger tests may include leakage current tests, lighting tests, and aging tests.

The pad unit 190 includes a plurality of pads P for transferring power and / or signals supplied from the outside into the panel 110.

The first wiring group 120 is formed in an outer region of the organic light emitting display panels 110, for example, a boundary region between the panels 110 in a first direction (vertical direction). The first wire group 120 includes a plurality of wires that receive a test power and / or a signal from the outside through the test pad TP. As a result, the first wiring group 120 simultaneously supplies the inspection power and / or signals supplied from the outside to the panels 110 arranged in the first direction.

For example, the first wiring group 120 may include a first wiring 121 supplied with the first pixel power ELVDD and a second wiring 122 supplied with the scan control signal SCS. Can be. Here, although the second wiring 122 is illustrated as one wiring, it may actually be composed of a plurality of wirings. For example, the second wiring 122 may be composed of three wirings that receive a start pulse SP, a scan clock signal CLK, and an output enable signal OE, respectively. The first wiring group 120 is commonly connected to the panels 110 arranged in the same row, and transmits a test power and / or a signal supplied to the first wiring group 110 to the panel 110 connected to the first wiring group 120.

The second wiring group 130 is formed in an outer region of the organic light emitting display panels 110, for example, a boundary region between the panels 110 in a second direction (horizontal direction) crossing the first direction. The second wiring group 130 includes a plurality of wirings that receive a test power and / or a signal from the outside through the test pad TP. As a result, the second wiring group 130 simultaneously supplies the inspection power and / or signals supplied from the outside to the panels 110 arranged in the second direction.

For example, the second wiring group 130 receives the third wiring 131 supplied with the second pixel power ELVSS from the outside, and the ledger inspection control signal and the ledger inspection signal (second inspection signal). The fourth wiring 132 may be included. Here, the fourth wiring 132 is shown as one wiring, but may be actually composed of a plurality of wirings. For example, the fourth wiring 132 may be composed of four wires receiving the ledger inspection control signal, the red ledger inspection signal, the green ledger inspection signal, and the blue ledger inspection signal, respectively. In addition, the second wiring group 130 further includes a fifth wiring 133 and / or a sixth wiring 134 that receive the first reference power supply voltage VGH and the second reference power supply voltage VGL from the outside, respectively. It can be configured to include. The second wiring group 130 is connected to the panels 110 arranged in the same row in common, and transmits the power and / or signal for ledger inspection supplied to itself to the panel 110 connected to the ledger during the ledger unit inspection. do.

When the mother substrate 100 of the present exemplary embodiment is used, a plurality of organic light emitting display panels 110 formed on the mother substrate 100 using the first and second wiring groups 120 and 130 may be ledger units. Aging test can be performed.

Hereinafter, a method of performing an aging test in the ledger unit on the mother substrate 100 will be described in detail.

First, the heater coupled to the base plate of the aging device is operated to apply heat to the mother substrate 100 placed on the base plate. The first and second reference power supply voltages VGH and VGL and the scan control signals are supplied to the scan driver 140 of each panel through the first and second wiring groups 120 and 130, and the second inspector is provided. The ledger inspection control signal and the aging signal are supplied to 180, and the first and second pixel power sources ELVDD and ELVSS are supplied to the pixel unit 150. In addition, the initialization power source Vinit may be further supplied through the first or second wiring groups 120 and 130 according to the structure of the pixels constituting the pixel unit 150.

When the first and second reference power supply voltages VGH and VGL and the scan control signals are supplied to the scan driver 140, the scan driver 140 generates a scan signal and / or a light emission control signal correspondingly. The scan signal and / or the emission control signal generated by the scan driver 140 are supplied to the pixel unit 150 through the scan lines S1 to Sn and / or the emission control lines E1 to En.

When the ledger inspection control signal and the aging signal are supplied to the second inspection unit 180, the second inspection unit 180 supplies the aging signal to the pixel unit 150 in response to the ledger inspection control signal.

Then, the pixel unit 150 emits light for a predetermined time corresponding to the scan signal and / or the emission control signal, the aging signal, and the first and second pixel power sources ELVDD and ELVSS.

That is, by supplying driving powers and driving signals for aging to the panels 110 through the first and second wiring groups 120 and 130, an aging test is performed while a predetermined current flows through the panels 110. Is performed.

However, since the first and second pixel power sources ELVDD and ELVSS are supplied in the form of a DC power source, a voltage drop occurs in the process of being supplied via the first and / or second wiring groups 120 and 130. . In particular, although only panels 110 arranged in a matrix type of three rows and three columns are illustrated in FIG. 4, much more panels 110 are disposed on the actual mother substrate 100. That is, in practice, as the lengths of the ledger wirings for supplying the first and second pixel power sources ELVDD and ELVSS become longer, the voltage drop may increase. In addition, in order to prevent this, a width of the ledger wirings for supplying the first and second pixel power sources ELVDD and ELVSS may be designed. However, since the first and / or second wiring groups 120 and 130 including the mother wirings for supplying the first and second pixel power sources ELVDD and ELVSS are formed in the dead spaces of the panels 110, they are spatially spaced. Due to the constraints, there are limitations in extending the width of the ledger wiring for supplying the first and second pixel power sources ELVDD and ELVSS.

The voltage drop of the first and second pixel power sources ELVDD and ELVSS is much greater than that of the first and second reference power supply voltages VGH and VGL, which consume power only when the scan driver 140 is switched. Occurs.

In addition, when aging the plurality of panels 110 in the ledger unit, aging must be performed by supplying a larger current at a time, thereby reducing the aging time and increasing its efficiency. However, in this case, a larger current flows in the ledger wires supplying the first and second pixel power sources ELVDD and ELVSS, thereby increasing the voltage drop in these ledger wires. The voltage drop is located at the center of the panel 110, for example, the mother substrate 100, which is relatively far from the test pad TP to which the first and second pixel power sources ELVDD and ELVSS are supplied. Larger in panels 110.

Accordingly, in the panel 110 in which the voltage drops of the first and second pixel power sources ELVDD and ELVSS are large, the first and second pixel power sources ELVDD and ELVSS and the first and second reference power supply voltages VGH, As the voltage difference between the VGL is increased, driving failure may occur, or a bright spot where a specific panel 110 shines brightly due to leakage current may occur.

In particular, when the voltage difference between the first pixel power supply ELVDD and the first reference power supply voltage VGH is deepened, driving failure and / or bright spots may occur. A more detailed description thereof will be described later with reference to FIGS. 6 and 7.

Therefore, in order to prevent this, in the present invention, the ledger wiring (first ledger wiring) for supplying the first pixel power source ELVDD and the ledger wiring (second ledger wiring) for supplying the first reference power supply voltage VGH are provided. Form in different directions. The voltage level of the first reference power supply voltage VGH is differentially applied to compensate for the voltage drop of the first pixel power supply ELVDD.

For example, the ledger wiring for supplying the first pixel power source ELVDD is set to the first wiring 121 included in the first wiring group 120, and the ledger wiring for supplying the first reference power supply voltage VGH. May be set as the fifth wiring 133 included in the second wiring group 130.

In this case, since the first pixel power source ELVDD is supplied in the column direction on the mother substrate 100, the voltage drop is different in units of rows. That is, when the first pixel power source ELVDD is supplied in both directions from the upper side and the lower side of the mother substrate 100, the first pixel having almost no voltage drop in the panels 110 arranged in the upper row and the lower row. Power source ELVDD is supplied. On the other hand, the first pixel power source ELVDD having a relatively low voltage level is supplied to the panels 110 arranged in the center row due to the voltage drop. In this case, since the first reference power supply voltage VGH is supplied in the row direction, different first reference power supply voltages VGH may be supplied to the panels 110 arranged in each row.

Therefore, in the present exemplary embodiment, the first reference power supply voltage VGH supplied to each row or grouped by a row unit is differentially applied in consideration of the voltage drop of the first pixel power supply ELVDD. Prevention of driving failure and / or bright spot of 110 is prevented. A more detailed description thereof will be described later with reference to FIG. 5.

Meanwhile, an electrical connection point between the first and second wiring groups 120 and 130 and the panels 110 is located outside the scribing line 101 of the panels 110. That is, the first to fourth scribing lines 101 of the plurality of scribing lines 101 for separating the plurality of organic light emitting display panels 110 formed on the mother substrate 100 are used. The panel 110 positioned inside the defined region is electrically connected to the first and second wiring groups 120 and 130 outside the region defined by the first to fourth scribing lines 101. .

As a result, after each panel 110 is scribed and separated into individual panels 110 as shown in FIG. 5, the first and second wiring groups 120 and 130 remove the panel 110. For example, the panel 110 may be electrically insulated from the scan driver 140, the pixel unit 150, the first inspector 160, the data distributor 170, and / or the second inspector 180. It does not affect the driving of.

As shown in FIG. 5, in the scribing completed panel 110, the first and second wiring groups 120 and 130 exist at the outside of the panel 110 with both ends floating. The driving of the panel 110 is not affected. On the other hand, although not shown in FIG. 5, the floated wires may be connected to the bias pad to receive the bias power to stabilize driving of the panel 110.

Meanwhile, in the present exemplary embodiment, the panel 110 of the organic light emitting display device is formed on the mother substrate 100, and the scan driver 140 is formed on the panels 110 together with the pixel unit 150. ), A driving circuit such as the data distribution unit 170 is formed, but the present invention is not limited thereto. For example, only the pixel unit 150 is formed in each of the panels 110, and the other driving circuits except this may be mounted on a printed circuit board and electrically connected to the pixel unit 150 through the pad unit 190. .

6 is a circuit diagram of an example of a pixel constituting a pixel unit of the organic light emitting display device of FIG. 5. For convenience, the pixel connected to the nth scan line and the mth data line will be illustrated in FIG. 6. However, the pixel illustrated in FIG. 6 is only one embodiment, and the present invention is not limited thereto.

4 and 6, the pixel 155 includes an organic light emitting diode OLED and a pixel circuit 152 for controlling the organic light emitting diode OLED.

The anode electrode of the organic light emitting diode OLED is connected to the pixel circuit 152, and the cathode electrode is connected to the second pixel power source ELVSS. The organic light emitting diode OLED emits light with a predetermined brightness in response to the current supplied from the pixel circuit 152.

The pixel circuit 152 includes first to sixth transistors T1 to T6 and a storage capacitor Cst.

The first transistor T1 is connected between the data line Dm and the first node N1, and the gate electrode of the first transistor T1 is connected to the current scan line Sn. The first transistor T1 is turned on when the scan signal (low level) is supplied to the current scan line Sn and supplies the data signal supplied from the data line Dm to the first node N1.

The second transistor T2 is connected between the first node N1 and the organic light emitting diode OLED, and the gate electrode of the second transistor T2 is connected to the second node N2. The second transistor T2 controls the amount of current flowing from the first node N1 to the organic light emitting diode OLED in response to the voltage of the second node N2.

The third transistor T3 is connected between the gate electrode of the second transistor T2 and the second electrode (drain electrode), and the gate electrode of the third transistor T3 is connected to the current scan line Sn. The third transistor T3 is turned on when the scan signal (low level) is supplied to the current scan line Sn, thereby diode-connecting the second transistor T2.

The fourth transistor T4 is connected between the second node N2 and the initialization power supply Vinit, and the gate electrode of the fourth transistor T4 is connected to the previous scan line Sn-1. The fourth transistor T4 is turned on when the scan signal (low level) is supplied from the previous scan line Sn- 1 to initialize the second node N2.

The fifth transistor T5 is connected between the first pixel power source ELVDD and the first node N1, and the gate electrode of the fifth transistor T5 is connected to the emission control line En. The fifth transistor T5 is turned off when the emission control signal (high level) is supplied from the emission control line En. The fifth transistor T5 is turned on when the emission control signal is not supplied, that is, when the emission control signal is set to a low level, thereby electrically connecting the first pixel power source ELVDD and the first node N1. Connect with

The sixth transistor T6 is connected between the second transistor T2 and the organic light emitting diode OLED, and the gate electrode of the sixth transistor T6 is connected to the emission control line En. The sixth transistor T6 is turned off when a high level emission control signal is supplied from the emission control line En to prevent the current from being supplied to the organic light emitting diode OLED. The sixth transistor T6 is turned on when the light emission control signal is not supplied, that is, when the light emission control signal is set to a low level, so that the current supplied from the second transistor T2 is supplied to the organic light emitting diode ( OLED).

The storage capacitor Cst is connected between the first pixel power source ELVDD and the second node N2 and receives a voltage corresponding to the difference between the voltages supplied to the first pixel power source ELVDD and the second node N2. Save it.

Meanwhile, an aging signal is supplied to the data line Dm of the pixel 155 during the aging test performed on the mother substrate 100 in the ledger unit. That is, the aging test is performed by driving the pixel 155 in response to the aging signal during the aging test period.

However, due to the voltage drop of the first pixel power source ELVDD supplied in the column direction during the aging test on the mother substrate 100, each of the panels 110 is in a row unit or a plurality of row unit groups. The first pixel power ELVDD having different voltage levels may be supplied. In this case, when the first reference power supply voltage VGH is equally applied to each of the panels 110, the first pixel power supply ELVDD and the first reference power supply voltage VGH supplied to the panels 110 in a row unit. ), The voltage difference is different. In this case, the voltage level of the first reference power supply voltage VGH is set based on the average value of the first pixel power supply ELVDD supplied to the panels 110.

Therefore, in the panels 110 having a relatively small voltage drop of the first pixel power source ELVDD, for example, the panels 110 arranged in the upper row and the lower row of the mother substrate 100 have the first pixel power source ELVDD. ) Is higher than the voltage level of the first reference power supply voltage (VGH) by more than the reference value may cause a drive failure.

More specifically, in the pixel 155, the emission control signal having the first reference power supply voltage VGH level supplied to the gate electrode of the fifth transistor T5 during the t1 and t2 periods of FIG. 7 is the first pixel power supply. The fifth transistor T5 may be turned on because the voltage level of the ELVDD is not greater than the threshold voltage of the fifth transistor T5. That is, the fifth transistor T5, which must remain off for the periods t1 and t2 of FIG. 7, is turned on, and driving failure may occur in each pixel 155.

In addition, the voltage level of the first pixel power source ELVDD is relatively high in panels 110 having a large voltage drop of the first pixel power source ELVDD, for example, the panels 110 arranged in the center row of the mother substrate 100. A bright spot may be generated by being smaller than the reference voltage level of the first reference power supply voltage VGH.

In addition, in the pixel 155, the emission control signal of the first reference power supply voltage VGH level supplied to the gate electrode of the fifth transistor T5 during the t1 and t2 periods of FIG. 7 is applied to the first pixel power source ELVDD. Much greater than the voltage level, leakage current may occur through the fifth transistor T5. That is, due to abnormal leakage current during the t1 and t2 periods, the first reference power supply voltage VGH supplied to the gate electrode of the fifth transistor T5 is transmitted to the first node N1 so that each pixel 155 emits light. can do. As a result, bright spots may occur on specific panels 110 of the mother substrate 100.

Therefore, when the first reference power supply voltage VGH is equally applied to each of the panels 110, an experimental reference value in which the voltage drop of the first pixel power supply ELVDD does not generate a predetermined reference value, that is, a driving failure and a clear point does not occur. The aging test had to be carried out within the limit. That is, in the aging test of the ledger unit before the present embodiment, the aging time is increased because the current that can be applied to the panels 110 during aging is limited, which acts as a factor of decreasing the efficiency of the aging test process. .

Therefore, in the present exemplary embodiment, an aging test is performed while applying heat to the panels 110, and the panel 110 is supplied to the panels 110 in a row unit to compensate for the voltage drop of the first pixel power source ELVDD. The first reference power supply voltage VGH is differentially applied.

FIG. 8 is a layout view of a ledger wiring for explaining a method of differentially applying a first reference power supply voltage in a mother substrate of the organic light emitting display shown in FIG. 4. For convenience, FIG. 8 illustrates only the arrangement of some of the ledger wirings that supply the first pixel power source and the first reference power supply voltage.

4 and 8, according to the present invention, the supply direction of the first pixel power source ELVDD and the first reference power supply voltage VGH are differently set to respective panels in the mother substrate.

For example, the first pixel power source ELVDD is commonly connected to the panels 110 arranged in the same column on the mother substrate 100 and through the first wiring group 120 formed in the first direction (vertical direction). Can be supplied. In addition, the first reference power supply voltage VGH is commonly connected to the panels 110 arranged in the same row on the mother substrate 100 and forms the second wiring group 130 formed in the second direction (horizontal direction). Can be supplied via However, the first direction and the second direction are not limited to the vertical direction and the horizontal direction, respectively. For example, the first direction may be set in the horizontal direction and the second direction may be set in the vertical direction.

At this time, the voltage level of the first reference power supply voltage VGH supplied in the second direction unit, that is, in each row unit, may be differentially applied to VGH1, VGH2, ..., VGHk, ..., VGH2k-1, and VGH2k. Can be.

In this case, the voltage level of the first reference power supply voltage VGH to be differentially applied corresponds to the voltage drop amount of the first pixel power supply ELVDD and is set differently according to the arrangement position of the panels 110. That is, the voltage level of the first reference power supply voltage VGH is differentially applied in consideration of the distance from the supply power supply of the first pixel power supply ELVDD to the panels 110, and in particular, the supply of the first pixel power supply ELVDD. The farther the distance from the power source to the panels 110 is, the smaller it is set.

For example, the voltage levels of VGH1 and VGH2k may be set identically, and the voltage levels of VGH2 and VGH2k-1 may be set lower than the voltage levels of VGH1 and VGH2k by a predetermined voltage level. And, the voltage level of VGHk can be set lower than VGH2 and VGH2k-1. In addition, the voltage level of the first reference power supply voltage VGH supplied in each row unit may be differentially applied in the same manner. In addition, this may be differentially applied to each row, or may be classified into groups of row units and differentially applied to each group.

In addition, the voltage level of the first reference power supply voltage VGH may be set corresponding to the current values to be applied to the panels 110 to shorten the aging time. For example, the voltage level of the first reference power supply voltage VGH is adjusted according to the voltage drop of the first pixel power supply ELVDD at the position where the panels 110 are arranged in correspondence with the current value to be applied during the aging test. It can be determined experimentally. For example, as the aging signal supplied from the ledger wiring (third ledger wiring) included in the first or second wiring groups 120 and 130 increases, the first reference power supply voltage VGH applied differently for each row unit. The voltage difference between the voltage levels can be set larger.

According to the present invention, panels arranged on the mother substrate 100 are arranged in different directions with the ledger wiring for transmitting the first pixel power supply ELVDD and the ledger wiring for transmitting the first reference power supply voltage VGH. In consideration of the voltage drop of the first pixel power source ELVDD according to the position of 110, the voltage level of the first reference power source voltage VGH supplied to the panels 110 is differentially applied. As a result, the aging process time can be shortened by increasing the aging current while compensating for the voltage drop of the first pixel power source ELVDD to prevent driving failure and bright spots of the panels 110. In addition, by performing an electrical aging test while supplying heat to the mother substrate 100, it is possible to shorten the aging time and improve its efficiency.

Meanwhile, in the present invention, the differential application of the first reference power supply voltage VGH according to the voltage drop of the first pixel power supply ELVDD is described using the pixel 155 illustrated in FIG. 6 as an example. It is not limited to this. For example, when the pixels are formed of an NMOS type transistor, the second reference power supply voltage VGL may be differentially applied according to the voltage drop of the second pixel power supply ELVSS. That is, according to the present invention, the voltage in the mother wirings for simultaneously supplying the first and / or second pixel power sources ELVDD and ELVSS to the panels 110 on the mother substrate 100 as shown in FIG. In consideration of the drop, the first and / or second reference power supply voltages VGH and VGL may be differentially applied to determine high and low level voltages of driving signals such as a scan signal and / or a light emission control signal. have.

The scope of the above-described invention is defined in the following claims, which are not bound by the description of the specification, and all modifications and variations belonging to the equivalent scope of the claims will belong to the scope of the present invention.

1 is a block diagram of a mother substrate aging apparatus according to an embodiment of the present invention.

FIG. 2 is a plan view specifically showing an example of the mother substrate aging apparatus of FIG. 1. FIG.

3 is a schematic front view of the mother substrate aging apparatus of FIG.

4 is a plan view of an example of a mother substrate on which an aging test is performed by the aging apparatus of this embodiment.

FIG. 5 is a plan view of an organic light emitting display panel cut in the mother substrate of FIG. 4. FIG.

FIG. 6 is a circuit diagram of an example of a pixel constituting a pixel portion of the organic light emitting display panel of FIG. 5. FIG.

FIG. 7 is a waveform diagram illustrating driving signals for driving the pixel illustrated in FIG. 6.

FIG. 8 is a layout diagram of a mother substrate for explaining a method of differentially applying a first reference power voltage in the mother substrate shown in FIG. 4.

<Description of the symbols for the main parts of the drawings>

10: aging device 20: base plate

30: signal supply unit 40: heater

50: main sensor 60: vacuum pad

70: drive unit 80: control unit

100: mother substrate 110: organic light emitting display panel

155 pixels

Claims (14)

A mother substrate aging device for aging testing a mother substrate in which a plurality of organic light emitting display panels are listed. A base plate on which the mother substrate is placed; A heater coupled to the base plate and supplying heat to the mother substrate; And And a signal supply unit configured to apply an aging signal to the pixels of each panel to emit light. The method of claim 1, A sensor coupled to the base plate and detecting a temperature of the base plate; And And a control unit for controlling the heater based on the temperature information transmitted from the sensor. The method of claim 2, And the control unit controls the heater so that the temperature of the organic light emitting display panel is maintained in a range of 70 ° C. or higher and less than 80 ° C. The method of claim 1, And a vacuum pad penetrating the base plate in a thickness direction to be exposed to one surface of the base plate and to closely adhere the mother substrate to one surface of the base plate. The method of claim 1, And a plurality of auxiliary sensors distributed in the base plate to monitor temperatures of respective portions of the base plate. The method of claim 1, And a driving part coupled to one surface of the base plate and moving the base plate up and down. The method of claim 1, The signal supply unit has a built-in control program for driving the respective panels, the mother substrate aging device for displaying the aging test status of each panel. The method of claim 7, wherein And the pixel power source is individually applied to organic light emitting display panels in at least one row or column direction of the mother substrate. Placing a mother substrate on which a plurality of organic light emitting display panels are formed, on a base plate; Supplying heat to the base plate through a heater coupled to the base plate; And And supplying an aging signal to each of the organic light emitting display panels. The method of claim 9, Sensing the temperature of the mother substrate through a sensor coupled to the base plate; And And controlling the heater in a controller coupled to the sensor and the heater so that the temperature of the mother substrate is maintained within a set temperature range. The method of claim 10, The set temperature range is 70 ℃ or more, less than 80 ℃ aging method of the mother substrate. The method of claim 9, The method of aging the mother substrate further comprises the step of contacting the mother substrate to one surface of the base plate with a vacuum pad coupled to the base plate. The method of claim 9, And monitoring the temperatures of the respective portions of the base plate through a plurality of auxiliary sensors distributed in the base plate. The method of claim 9, The supplying of the aging signal may include separately supplying an aging signal to organic light emitting display panels formed in at least one row direction or column direction on the mother substrate.

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