This application claims priority to Chinese Patent Application No. 201810094851.5, filed with the State Intellectual Property Office on Jan. 31, 2018 and titled “DETECTING APPARATUS AND METHOD, REPAIRING APPARATUS AND METHOD, AND REPAIRING SYSTEM OF AMOLED DISPLAY DEVICE”, the entire contents of which are incorporated herein by reference.
The present disclosure relates to a detecting apparatus and a method thereof, a repairing apparatus and a method thereof, and a repairing system of AMOLED display device.
An AMOLED (Active-matrix organic light-emitting diode) display device has the characteristics of low driving voltage, long operating life and high resolution, which is an OLED display device with huge potentials.
After the manufacture of an AMOLED display device is completed, it is need to detect the luminance of each region on its screen. The smaller the difference in luminance among regions on the screen of the AMOLED display device, the better the luminance uniformity of the screen of the AMOLED display device. If there is a region having an excessively high or low luminance on the screen, it is considered that the AMOLED display device has a Mura defect, i.e., the screen luminance is not uniform.
There are provided in embodiments of the present disclosure a detecting apparatus and a method thereof, a repairing apparatus and a method thereof, and a repairing system of AMOLED display device.
There is provided in at least one embodiment of the present disclosure a detecting apparatus of an AMOLED display device, comprising: an illuminating device configured to sequentially illuminate a plurality of detection regions of a screen of the AMOLED display device, the screen being divided into the plurality of detection regions, each of the detection regions comprising at least one light-emitting unit; a current detecting device configured to acquire a detection current which is a sum of driving currents of the light-emitting units in the detection regions being illuminated; and a judging device configured to judge whether the detection region corresponding to the detection current is a defective region according to the detection current.
Optionally, the plurality of detection regions have any of the following formations: the plurality of detection regions are in a first direction, each of the detection regions being in a strip shape and extending in a second direction, and the second direction being perpendicular to the first direction; and the plurality of detection regions is in a matrix shape.
Optionally, the judging device comprises: a calculating circuit configured to calculate a ratio of the detection current to a current reference value which is one of a set value and an average value of the detection currents of the detection regions; and a judging circuit configured to determine whether the detection region is a defective region according to the ratio.
Optionally, the detecting apparatus further comprises: a storage device configured to store position information of the defective region that is determined.
Optionally, each of the detection regions comprises 4 to 8 pixel structures.
There is provided in at least one embodiment of the present disclosure a repairing apparatus of an AMOLED display device, configured to repair the defective region detected by the detecting apparatus of the AMOLED display device, comprising: a determining device configured to determine positions of the defective regions; an acquiring device configured to acquire a current density of a normal region when light-emitting unit in the normal region is illuminated, the normal region being a region other than the defective regions on the screen of the AMOLED display device; and a compensating device configured to perform current compensation on the defective regions based on the current density of the normal region.
Optionally, the determining device is configured to determine the position of the defective region in any of the following ways: determining the positions of the defective regions based on luminance of respective detection regions on the screen; determining the positions of the defective regions based on a ratio of detection current of respective detection regions to a current reference value, the screen being divided into a plurality of detection regions, the detection current being a sum of driving currents of light-emitting units in the detection regions being illuminated, and the current reference value being one of a set value and an average value of the detection currents of the detection regions; and determining the positions of the defective regions based on position information of the defective regions.
Optionally, the acquiring device is configured to calculate a ratio of a sum of driving currents of the light-emitting units in the normal region to an area of the normal region, so as to acquire the current density of the normal region.
Optionally, the compensating device comprises: a voltage determining unit configured to determine a data signal voltage of the defective regions based on a comparison relationship between the current density and the data signal voltage of the defective regions, such that the current density of the defective regions is equal to the current density of the normal region under effect of a correction voltage, the correction voltage being the data signal voltage of the defective regions being determined; and an entering unit configured to enter the correction voltage of the defective regions into a driver chip of the AMOLED display device.
There is provided in at least one embodiment of the present disclosure a detecting method of an AMOLED display device, comprising the following steps: sequentially illuminating a plurality of detection regions of a screen of the AMOLED display device, the screen being divided into the plurality of detection regions, each of the detection regions comprising at least one light-emitting unit; acquiring a detection current which is a sum of driving currents of the light-emitting units in the detection regions being illuminated; and judging whether the detection region corresponding to the detection current is a defective region according to the detection current.
Optionally, the plurality of detection regions have any of the following formations: the plurality of detection regions are in a first direction, each of the detection regions being in a strip shape and extending in a second direction, and the second direction being perpendicular to the first direction; and the plurality of detection regions is in a matrix shape.
Optionally, the step of judging whether the detection region corresponding to the detection current is the defective region according to the detection current includes: calculating a ratio of the detection current to a current reference value which is one of a set value and an average value of the detection currents of the detection regions; and determining whether the detection region is a defective region according to the ratio.
Optionally, the detecting method further comprises: storing position information of the defective regions being determined.
Optionally, each of the detection regions comprises 4 to 8 pixel structures.
There is provided in at least one embodiment of the present disclosure a repairing method of an AMOLED display device, configured to repair the defective region detected by the detection method for the AMOLED display device, comprising the following steps: determining positions of the defective regions; acquiring a current density of a normal region when the light-emitting unit in the normal region is illuminated, the normal region being a region other than the defective regions on the screen of the AMOLED display device; and performing current compensation on the defective region according to the current density of the normal region.
Optionally, the step of determining a position of the defective region is performed in any of the following ways: determining the positions of the defective regions based on luminance of respective detection regions on the screen; determining the positions of the defective regions based on a ratio of detection current of respective detection regions to a current reference value, the screen being divided into a plurality of detection regions, the detection current being a sum of driving currents of the light-emitting units in the detection regions that are illuminated, and the current reference value being one of a set value and an average value of the detection currents of the detection regions; and determining the positions of the defective regions based on position information of the defective regions.
Optionally, the step of acquiring a current density of a normal region comprises: calculating a ratio of a sum of driving currents of the light-emitting units in the normal region to an area of the normal region, so as to acquire the current density of the normal region.
Optionally, the step of performing current compensation on the defective region according to the current density of the normal region comprises: determining data signal voltage of the defective regions based on a comparison relationship between the current density and the data signal voltage of the defective regions, such that the current density of the defective regions is equal to the current density of the normal region under effect of a correction voltage which is the data signal voltage of the defective regions being determined; and entering the correction voltage of the defective regions into a driver chip of the AMOLED display device.
Optionally, the repairing method further comprises: performing a luminance uniformity detection on the AMOLED display device after performing the current compensation to the defective region based on the current density of the normal region.
There is provided in at least one embodiment of the present disclosure a repairing system of an AMOLED display device, comprising a detecting apparatus and a repairing apparatus, wherein the detecting apparatus comprises: an illuminating device configured to sequentially illuminate a plurality of detection regions of a screen of the AMOLED display device, the screen being divided into the plurality of detection regions, each of the detection regions comprising at least one light-emitting unit; a current detecting device configured to acquire a detection current, and the detection current is a sum of driving currents of the light-emitting units in the detection regions that are illuminated; and a judging device configured to judge whether the detection region corresponding to the detection current is a defective region based on the detection current; wherein the repairing apparatus comprises: a determining device configured to determine positions of the defective regions based on position information of the defective regions; an acquiring device configured to acquire a current density of a normal region when the light-emitting unit in the normal region is illuminated, the normal region being a region other than the defective regions on the screen of the AMOLED display device; and a compensating device configured to perform current compensation on the defective regions based on the current density of the normal region.
The embodiments of the present disclosure will be described in further detail with reference to the enclosed drawings, in order to present the principles and advantages of the present disclosure more clearly.
Here, the screen of the AMOLED display device is divided into a plurality of detection regions. The illuminating device 110 is configured for sequentially illuminating the plurality of detection regions of the screen of the AMOLED display device. The current detecting device 120 is configured for acquiring a detection current, and the detection current is a sum of driving currents of light-emitting units in the illuminated detection region (the filled detection region in
At present, the luminance detection of the AMOLED display device is mainly realized via visual detection by workers. The worker feels the luminance of the screen, and judges whether the OLED display device has a problem of Mura defect. Such a detection method is not only inefficient, but also subjected to subjective views. Testing the same AMOLED display device by different workers may result in different testing results and reduced product yield, and the detected defect is hard to be repaired. In the embodiments of the present disclosure, the luminance uniformity of the AMOLED display device can be detected by dividing the screen of the AMOLED display device into a plurality of detection regions, sequentially illuminating the detection regions and acquiring detection currents of the detection regions, and judging whether a detection region is a defective region according to the detection current, thereby achieving high detection efficiency, unified standard and high accuracy, reducing the misjudgments, and facilitating the improvement of product yield.
Exemplarily, the illuminating device 110 can be a lighting machine. The current detecting device 120 can be a current sensor. The current sensor is connected at a joint between the lighting machine and the display device so as to acquire a total driving current output to the AMOLED display device when a certain region is illuminated by the lighting machine, and this current is the detection current of the corresponding region. Besides, for a lighting machine that has a function of detecting a magnitude of an output current, the driving current output from the lighting machine to the display device can also be acquired directly by the lighting machine. After the detection current is acquired by the current detecting device 120, a value of the detection current of each detection region can be recorded to facilitating the subsequent applications, thereby avoiding repeated acquirements of the current value, which is beneficial for improving the detection efficiency.
When the detection regions 201 in
The screen of the AMOLED display device includes a plurality of light-emitting units distributed in an array. Here, the first direction can be a row direction of the light-emitting units distributed in the array, the second direction can be a column direction of the light-emitting units distributed in the array, Alternatively, the first direction can also be a column direction and the second direction can be a row direction.
When the detection regions 201 in
The entire screen 200 is divided into a plurality of detection regions 201, so that the entire screen 200 can be detected. Different dividing methods can be employed during implementation according to actual needs. The more the number of the divided detection regions, the higher the accuracy of the detection.
For example, for a display device with a screen length-width ratio of 24:9 or more, since the screen length-width ratio of such a display device is relatively large, the number of light-emitting units in a length direction of the screen is much greater than that in a width direction of the screen, and thus a large luminance difference is more likely to occur among different regions in the length direction. When such a display device is detected, it can be divided into a plurality of strip-shaped detection regions in the length direction of the screen, each of which extends in the width direction of the screen (such as the dividing method shown in
When the screen size is constant, the larger the detection region is, the smaller the total number of the divided detection regions is, and the fewer the corresponding detection times are. At this point, the detection accuracy is low and the detection efficiency is high. On the contrary, the smaller the detection region is, the greater the total number of the divided detection regions is, and the more the corresponding detection times are. At this point, the detection accuracy is high and the detection efficiency is low. When the detection regions are divided, the size of the detection region can be set according to different requirements. For a display device with a higher requirement for display effect, the detection regions can be set to be smaller. For a display device with a lower requirement for display effect, the detection regions can be set to be larger.
Exemplarily, each detection region can include 4 to 8 pixel structures. The pixel structures of different display devices can include different numbers of light-emitting units. For example, a single pixel structure can include three light-emitting units. A single pixel structure of a certain kind of display device includes a light-emitting unit that emits red light, a light-emitting unit that emits green light and a light-emitting unit that emits blue light. When the detection regions of such a display device are divided, if each detection region includes 4 pixel structures, then each detection region includes 12 light-emitting units.
The smaller the detection region is, the fewer the number of the light-emitting units in the detection region is. When the detection region is so small that it only includes one light-emitting unit, it is equivalent to that the light-emitting units are detected one by one. As such, the detection result is the most accurate, but correspondingly the detection efficiency is the lowest, and the detection cost is also high. In general, the size of each detection region is set to be a size of 4 to 8 pixel structures, so that the detection result has relatively high accuracy to satisfy the detection requirement.
When the current reference value is an average value of the detection currents of the detection regions, if the detection current is closer to the current reference value, i.e., the ratio is more approximate to 1, this indicates that the luminance of the detection region is closer to the average luminance of the detection regions. The smaller the luminance difference between different detection regions is, the more uniform the screen luminance is.
The set value can be set according to design requirements. For example, a corresponding set value can be set in accordance with a luminance requirement of a designed display device. If the detection current is closer to the current reference value, i.e., the ratio is more approximate to 1, this indicates that the luminance of the detection region is closer to a required luminance. If the detection current of respective detection region is close to the current reference value, the smaller the luminance difference between different detection regions is, the more uniform the screen luminance is.
Exemplarily, when the ratio is within a range of 0.9 to 1.1, the corresponding detection region can be regarded as a normal region, and when the ratio is less than 0.9 or greater than 1.1, the corresponding detection region can be regarded as a defective region. In practice, it is hard to ensure that the detection current of the detection region is completely equal to the current reference value, so when the ratio is within a certain range, the detection region can be regarded as a normal region. The range of the ratio can be set according to different design requirements. For a display device with a higher design requirement, the range of the ratio can be set to be smaller, such as 0.95 to 1.05, and for a display device with a lower design requirement, the range of the ratio can be set to be larger, such as 0.8 to 1.2.
Exemplarily, it is also possible to determine whether each detection region is a defective region according to an absolute value of a difference between the detection current and the current reference value. When the absolute value of the difference between the detection current and the current reference value is smaller, the luminance of the detection region is closer to the luminance of the other detection regions, and the smaller the luminance difference between different detection regions is, the more uniform the screen luminance is.
Optionally, the detecting apparatus can also comprise a storage device. The storage device is configured for storing position information of the determined defective region, so as to facilitate acquirement of a position of the defective region when the defective region is repaired. The position information can be a virtual coordinate, which can be a one-dimensional coordinate or a two-dimensional coordinate. For example, if the filled region in
The current compensation to the defective region of a display device can be performed according to the current density of the normal region, thereby changing the luminance of the defective region and reducing a luminance difference between the defective region and the normal region, which is beneficial for improving the display effect and the yield.
The current density referred to in the present disclosure is a ratio of a sum of driving currents, when all the light-emitting units in a certain region on the screen of the AMOLED display device are illuminated, to an area of the region. For example, the current density of the normal region is a ratio of a sum of driving currents when all the light-emitting units in the normal region are illuminated to an area of the normal region. The area of each region can be represented by a size of a plane enclosed by a profile of the region, and the unit can be square millimeter and square centimeter, etc. For example, the current density of a certain region is 3 mA/mm2. In addition, since the distribution of the light-emitting units on the screen is generally uniform, the area of each region can also be represented as the number of the light-emitting units in the region, and the unit can be one light-emitting unit. For example, the current density of a certain region is 5 mA per light-emitting unit.
In an implementation of embodiments of the present disclosure, the determining device 410 can be configured to determine the position of the defective region according to the luminance of each region on the screen. Exemplarily, the luminance detection can be performed on each region of the screen through a luminance meter, so as to determine the position of each defective region. For example, only one detection region is illuminated each time, and then the luminance value of the region is detected through the luminance meter, so that luminance values of all the detection regions can be detected. A detection region in which a difference between the detected luminance value and an average luminance value or a difference between the detected luminance value and a set luminance value is beyond a certain range is a defective region.
In another implementation of embodiments of the present disclosure, the determining device 410 can also be configured to determine the position of the defective region according to a ratio of the detection current of each detection region to the current reference value. The screen is divided into a plurality of detection regions, the detection current is a sum of driving currents of the light-emitting units in the detection region which is illuminated, and the current reference value is one of a set value and an average value of the detection currents of the detection regions. In an implementation, the display device can be detected by using the aforementioned detecting apparatus of an AMOLED display device, so as to determine the position of each defective region on the screen.
In another implementation of embodiments of the present disclosure, the determining device 410 can also be configured to determine the position of the defective region according to position information of the defective region. The determining device 410 can directly acquire position information of each defective region through the aforementioned storage device, so as to find the position of each defective region rapidly and accurately in the repair process, thereby improving the repair efficiency while avoiding omissions of repair.
The acquiring device 420 can be configured to calculate a ratio of a sum of driving currents of the light-emitting units in the normal region to an area of the normal region, so as to acquire the current density of the normal region. In
Take the plurality of regions shown in
The sum of driving currents of the light-emitting units of the normal region can be acquired by using the aforementioned current detecting device in the detecting apparatus of the AMOLED display device. For example, the sum of driving currents of the light-emitting units of the normal region can be acquired by illuminating only the normal region. Exemplarily, the aforementioned illuminating device can be configured to illuminate the normal region, and the sum of driving currents of the light-emitting unit of the normal region can be detected by using the current detecting device. Alternatively, the entire screen can also be illuminated, and a sum of driving currents of all the light-emitting units can be acquired when the entire screen is illuminated, then I0 can be acquired by subtracting I1, I2 and I3 from the sum.
In addition, the detection current of each detection region can also be recorded when detections are performed by using the aforementioned detecting apparatus, and a sum of detection currents of the detection regions in the normal region the I0.
In a driving circuit of the light-emitting unit of the AMOLED display device, the driving current of a light-emitting unit has a correspondence relationship with the data signal voltage. Exemplarily,
As can be seen from the current formula of thin film transistors,
It can be known that the driving current I of the light-emitting unit D is related to the data signal voltage VData. The driving circuit I can be changed by changing the magnitude of the data signal voltage VData. For a defective region, the current density thereof can be changed by changing the data signal voltage VData of all the light-emitting units therein, such that the current density of the defective region can be the same as that of the normal region, thereby achieving the purpose of changing the luminance of the defective region and reducing a luminance difference between the defective region and the normal region.
In the formula (1), Cox is a channel capacitance per unit area of the thin film transistor, μ is a channel mobility, W is a channel width of the thin film transistor, L is a channel length of the thin film transistor, and Vth is a threshold voltage of the thin film transistor. These variables are different for different thin film transistors, but VDD, which is a voltage of the driving power source, is a fixed value.
Since the area of the normal region is usually larger than the area of each defective region (as shown in
The comparison relationship between the current density and the data signal voltage of the defective region can be acquired by tests before the repair. The comparison relationship between the current density and the data signal voltage of the defective region can be recorded in a form of chart, so that the corresponding data signal voltage can be selected by looking up in the chart.
Exemplarily, the data signal voltage VData of the defective region can be changed for many times, and a current density of the defective region is acquired after each time the data signal voltage VData has been changed, as such, the aforementioned curve of comparison relationship between the current density and the data signal voltage of the defective region can be drawn. After each time the data signal voltage VData has been changed, the current density of the defective region can be acquired by the aforementioned acquiring device. The acquiring device can also be configured to calculate a ratio of a sum of driving currents of the light-emitting units in the defective region to an area of the defective region, thereby acquiring the current density of the defective region.
When drawing the curve of comparison relationship, the drawn curve of comparison relationship is more accurate when more data of the data signal voltage VData and current density is acquired. When drawing the curve of comparison relationship, at least the following three groups of data can be acquired: a current density of the defective region when the data signal voltage VData of the defective region is a default value (i.e., the data signal voltage before repair); a current density of the defective region when the data signal voltage VData is greater than the default value; and a current density of the defective region when the data signal voltage VData of the defective region is smaller than the default value. If the data signal voltage VData of the defective region and the current density of the defective region which have been changed for many times are recorded in one-to-one correspondence, then the aforementioned chart can be acquired.
Optionally, respective comparison relationships between the current density and the data signal voltage of the defective region can be acquired in different defective regions. Take
Exemplarily, a plurality of different defective regions can also be repaired only according to the comparison relationship between the current density and the data signal voltage of one of the defective regions. Take
Exemplarily, it is also doable to continuously adjust (continuously increase or decrease) the data signal voltage of the defective region and acquire the current density of the defective region at real time, until the current density of the defective region is the same as that of the normal region.
In step S11, a plurality of detection regions of the screen of the AMOLED display device are illuminated sequentially.
For example, the step S11 can be executed by the aforementioned illuminating device.
Here, the screen of the AMOLED display device is divided into a plurality of detection regions, each of which includes at least one light-emitting unit. The division of the detection regions of the screen of the AMOLED display device can be referred to
When the detection regions in
The screen of the AMOLED display device includes a plurality of light-emitting units distributed in an array. Here, the first direction can be a row direction of the light-emitting units distributed in an array, the second direction can be a column direction of the light-emitting units distributed in an array. In other embodiments, the first direction can also be a column direction and the second direction can also be a row direction.
As shown in
When the detection regions in
The entire screen 200 is divided into a plurality of detection regions 201 so that the entire screen 200 can be detected, which improves the accuracy of the detection, and different division methods can be employed to satisfy different needs.
For example, for a display device with a screen length-width ratio of 24:9 or more, since the screen length-width ratio of such a display device is relatively large, the number of light-emitting units in a length direction of the screen is much greater than that in a width direction of the screen, and thus a large luminance difference is more likely to occur among different regions in the length direction. When such a display device is detected, it can be divided into a plurality of strip-shaped detection regions in the length direction of the screen, each of which extends in the width direction of the screen, such as the dividing method shown in
When the screen size is constant, the larger the detection region is, the smaller the total number of the divided detection regions is, and the fewer the corresponding detection times are. At this point, the detection accuracy is low and the detection efficiency is high. On the contrary, the smaller the detection region is, the greater the total number of the divided detection regions is, and the more the corresponding detection times are. At this point, the detection accuracy is high and the detection efficiency is low. When the detection regions are divided, the size of the detection regions can be set according to different requirements. For a display device with a higher requirement for display effect, the detection regions can be set to be smaller, and for a display device with a lower requirement for display effect, the detection regions can be set to be larger.
Exemplarily, each detection region can include 4 to 8 pixel structures. The pixel structure of different display devices can include different numbers of light-emitting units, for example, a single pixel structure can include three light-emitting units. A single pixel structure of a certain kind of display device includes a light-emitting unit that emits red light, a light-emitting unit that emits green light and a light-emitting unit that emits blue light. When dividing the detection regions of such a display device, if each detection region includes 4 pixel structures, then each detection region includes 12 light-emitting units.
The smaller the detection region is, the fewer the number of the light-emitting units in the detection region is. When the detection region is so small that it includes only one light-emitting unit, it is equivalent to that the light-emitting units are detected one by one. In this way, the result of the detection is the most accurate, but correspondingly the detection efficiency is the lowest, and the detection cost is also high. In general, the size of each detection region is set to be a size of 4 to 8 pixel structures, so that the detection result has a relatively high accuracy to satisfy the detection requirement.
In step S12, a detection current is acquired.
Here, the detection current is a sum of driving currents of the light-emitting units in the detection regions which are illuminated.
For example, the step S12 can be executed by the aforementioned current detecting device.
In step S13, whether a detection region 201 corresponding to a detection current is a defective region is judged according to the detection current.
For example, the step S13 can be executed by the aforementioned judging device.
The screen of the AMOLED display device is divided into a plurality of detection regions, which are sequentially illuminated, and the detection currents of the detection regions are acquired. Whether a detection region is a defective region is judged according to the detection current, and in this way a detection of luminance uniformity can be performed for the AMOLED display device. As such, the detection efficiency is high, the detection standard is unified, and the accuracy is high.
Optionally, the step S13 may include: calculating a ratio of detection current to a current reference value, which is one of a set value and an average value of the detection currents of the detection regions; and determining whether a detection region is a defective region according to the ratio.
A luminance of a light-emitting unit is related to a magnitude of the driving current of the light-emitting unit. The greater the driving current is, the higher the luminance is. On the contrary, the smaller the driving current is, the lower the luminance is. By judging whether a detection region is a defective region through the ratio of the detection current to the current reference value, it is possible to accurately detect the region that is greatly different in luminance.
When the current reference value is an average value of the detection currents of the detection regions, if the detection current is closer to the current reference value, i.e., the ratio is more approximate to 1, this indicates that the light-emitting luminance of the detection region is more approximate to the average luminance of the detection regions. The smaller the luminance difference between different detection regions is, the more uniform the screen luminance is.
The set value can be set according to design requirements. For example, a corresponding set value can be set in accordance with a luminance requirement of a designed display device. If the detection current is closer to the current reference value, i.e., the ratio is more approximate to 1, this indicates that the luminance of the detection region is more approximate to the required luminance. If the detection current of every detection region is close to the current reference value, the smaller the luminance difference between different detection regions is, the more uniform the screen luminance is.
Exemplarily, when the ratio is within a range from 0.9 to 1.1, the corresponding detection region can be regarded as a normal region. When the ratio is smaller than 0.9 or greater than 1.1, the detection region is regarded as a defective region. In practice, it is hard to ensure that the detection current of the detection region is completely equal to the current reference value, so when the ratio is within a certain range, the detection region can be regarded as a normal region. The range of the ratio can be set according to different design requirements. For a display device with a higher design requirement, the range of the ratio can be set to be smaller, such as from 0.95 to 1.05, and for a display device with a lower design requirement, the range of the ratio can be set to be larger, such as from 0.8 to 1.2.
Exemplarily, it is also possible to determine whether each detection region is a defective region according to an absolute value of a difference between the detection current and the current reference value. When the absolute value of the difference between the detection current and the current reference value is smaller, the light-emitting luminance of the detection region is closer to the luminance of the other detection regions, and the smaller the luminance difference between different detection regions is, the more uniform the screen luminance is.
Optionally, after the step S13, the detecting method can also comprise a step of storing position information of the determined defective region, so as to facilitate acquirement of the position of the defective region when the defective region is repaired. The position information can be a virtual coordinate, which can be a one-dimensional coordinate or a two-dimensional coordinate. For example, if the filled region in
As shown in
Exemplarily, the position of the defective region can be determined according to a luminance of respective detection regions on the screen. Alternatively, the position of the defective region is determined according to a ratio between the detection current and a current reference value of each detection region on the screen. The screen is divided into a plurality of detection regions, the detection current is a sum of driving currents of the light-emitting units in the detection region which is illuminated, and the current reference value is one of a set value and an average value of the detection currents of the detection regions.
For example, a determining device 410 can be employed to detect the display device by the aforementioned detecting apparatus of the AMOLED display device, so as to determine the position of each defective region on the screen. Alternatively, a luminance meter can be employed to perform luminance detection on each region of the screen, so as to determine the position of each defective region. Alternatively, position information of each defective region can also be utilized directly through the aforementioned storage device, such that the position of each defective region is found rapidly and accurately during the repair process, which improves the repair efficiency and avoids omissions of repair.
Exemplarily, the step S21 can be executed by the aforementioned determining device.
In step S22, a current density of the normal region when the light-emitting unit of the normal region is illuminated is acquired.
The current density of the normal region can be acquired by calculating a ratio of a sum of driving currents of the light-emitting units in the normal region to an area of the normal region. The sum of driving currents of the light-emitting units of the normal region can be acquired by the aforementioned step S12 in the detecting method of an AMOLED display device.
The area of each region can be represented by a size of a plane enclosed by a profile of the region, and the unit can be square millimeter and square centimeter, etc. For example, the current density of a certain region is 3 mA/mm2. In addition, since the distribution of light-emitting units on the screen is generally uniform, the area of each region can also be represented as the number of the light-emitting units in the region, and the unit can be one light-emitting unit. For example, the current density of a certain region is 5 mA per light-emitting unit.
For example, the step S22 can be executed by the aforementioned acquiring device.
In step S23, a current compensation is performed on the defective region according to the current density of the normal region.
For example, the step S23 can be executed by the aforementioned compensating device.
Exemplarily, the step S23 may include: determining a data signal voltage of the defective region according to a comparison relationship between the current density and the data signal voltage of the defective region, such that, a current density of the defective region can be equal to the current density of the normal region under the effect of the correction voltage. Here, the correction voltage is the data signal voltage of the determined defective region. This process can be executed by the aforementioned voltage determining unit in the compensating device.
The correction voltage of the defective region is entered into a driver chip of the AMOLED display device. This process can be executed by the aforementioned entering unit in the compensating device. Exemplarily, the determination process can be referred to the embodiments of the repairing apparatus of an AMOLED display device, which is not repeated here.
The embodiment of the present disclosure performs a current compensation to the defective region of the display device according to the current density of the normal region, thus a luminance of the defective region can be changed and a luminance difference between the defective region and the normal region can be reduced, which is beneficial for improving the display effect and the yield.
After the repair of the display device is completed, the display device can be detected again. If no defective region is found when the detection is repeated, it means that the repair is successful. If there is still a defective region, it means that the display device may have other deficiencies, such as a short circuit of thin film transistor, and other methods are needed to repair the display device.
In the embodiments of the present disclosure, by dividing the screen of the AMOLED display device into a plurality of detection regions, sequentially illuminating the detection regions, and acquiring the detection currents of the detection regions, and then judging whether a detection region is a defective region according to the detection current, the luminance uniformity of the AMOLED display device can be detected with high detection efficiency, a unified standard and high accuracy. By performing a current compensation to the defective region of the display device according to the current density of the normal region, it is possible to change the luminance of the defective region and reduce a luminance difference between the defective region and the normal region, which is beneficial for improving the display effect and the yield.
The foregoing descriptions are merely exemplary embodiments of the present disclosure, and are not intended to limit the present disclosure. Within the spirit and principles of the disclosure, any modifications, equivalent substitutions, improvements, etc., are shall fall into the protection scope of the appended claims of the present disclosure.
Number | Date | Country | Kind |
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2018 1 0094851 | Jan 2018 | CN | national |
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7474115 | Trujillo | Jan 2009 | B1 |
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Number | Date | Country | |
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20190237013 A1 | Aug 2019 | US |