CN106328030B

CN106328030B - Correction method and display device

Info

Publication number: CN106328030B
Application number: CN201510388863.5A
Authority: CN
Inventors: 张劲淳; 陈志豪
Original assignee: Forcelead Technology Corp
Current assignee: Forcelead Technology Corp
Priority date: 2015-07-06
Filing date: 2015-07-06
Publication date: 2020-10-30
Anticipated expiration: 2035-07-06
Also published as: CN106328030A

Abstract

The invention discloses a correction method and a display device, wherein the correction method is used for correcting the display brightness of the display device and comprises the steps of judging whether a display panel of the display device has at least one correction area; and if the display panel is judged to have the at least one correction area, carrying out compensation operation according to the difference value between the display brightness of the at least one correction area and preset brightness to enable the display brightness in the at least one correction area to be consistent with the preset brightness.

Description

Correction method and display device

Technical Field

The present invention relates to a correction method and a display device, and more particularly, to a correction method capable of correspondingly correcting and compensating display brightness at a defect of a display device.

Background

For the convenience of carrying about, the weight and size of the mobile electronic device become the most important consideration for users, wherein the development of the narrow-frame mobile electronic device becomes a popular type in the market, and for realizing the narrow-frame mobile electronic device, the Gate driver circuit substrate technology (GAO) is correspondingly used to drive the display device, and the Gate driver circuit is disposed on the glass substrate of the display device, so as to reduce the required design area and the arrangement of the related routing.

However, the gate driving circuit fabricated by using non-single crystal silicon is prone to have problems of process stability, uniformity or reliability, and the display device using the gate driving circuit substrate technology often has problems of horizontal line defects of some specific pixel units, which results in a decrease in the production yield of related products. In order to solve the problem, the conventional method only needs to control the manufacturing process, material, equipment or quality of the display device to effectively maintain the production yield of the display device. Once the pixel units of the display device have the problem of horizontal line defects, some display devices with less serious horizontal line defects may be included, but because the hardware conditions of the display devices cannot meet the requirements of the client, the display devices can only be discarded but cannot be recycled, thereby causing a waste of cost.

Therefore, it is an important subject of the art to provide a correction method capable of correspondingly correcting and compensating the display brightness at a defect on the display device.

Disclosure of Invention

Therefore, it is a primary objective of the present invention to provide a correction method for correcting and compensating the display brightness at a defect on a display device.

The invention discloses a correction method, which is used for correcting the display brightness of a display device and comprises the steps of judging whether a display panel of the display device has at least one correction area; and if the display panel is judged to have the at least one correction area, carrying out compensation operation according to the difference value between the display brightness of the at least one correction area and preset brightness to enable the display brightness in the at least one correction area to be consistent with the preset brightness.

The invention also discloses a display device, which comprises a processor for generating a control signal; a display panel coupled to the processor and including a plurality of pixel units; and a storage device coupled to the processor and storing a program code, the program code calibrating a display brightness of the plurality of pixel units according to the control signal, the display method includes determining whether there is at least one calibration area on the display panel; and if the display panel is judged to have the at least one correction area, performing compensation operation according to the difference value between the display brightness and preset brightness of the plurality of pixel units in the at least one correction area to enable the display brightness to be consistent with the preset brightness.

Drawings

Fig. 1 is a schematic diagram of a display device according to an embodiment of the invention.

FIG. 2 is a flowchart of a calibration process according to an embodiment of the present invention.

FIG. 3 is a diagram illustrating a digital imaging operation according to an embodiment of the present invention.

FIG. 4 is a diagram illustrating another digital imaging operation according to an embodiment of the present invention.

FIG. 5 is a diagram illustrating an exemplary operation of analog gamma compensation according to the present invention.

Fig. 6A to 6C are schematic diagrams illustrating compensation performed on a display screen according to an embodiment of the invention.

FIG. 7 is a diagram illustrating a defect display according to an embodiment of the present invention.

Wherein the reference numerals are as follows:

10 display device

100 processor

102 display panel

104 storage device

20 shows the procedure

200. 202, 204, 206 steps

70 defective display picture

C1, C3, C5, C7 dotted line

Solid lines of C2, C4, C6 and C8

C9 voltage regulation curve

DL1 defective area

DL2 correction area

DL3 Normal display area

Detailed Description

Certain terms are used throughout the description and following claims to refer to particular components. As one of ordinary skill in the art will appreciate, manufacturers may refer to a component by different names. In the present specification and the claims to follow, differences in names are not used as means for distinguishing components, but are used as a basis for distinguishing components in terms of differences in functions. In the following description and in the claims, the terms "include" and "comprise" are used in an open-ended fashion, and thus should be interpreted to mean "include, but not limited to. Furthermore, the term "coupled" is intended to encompass any direct or indirect electrical connection. Thus, if a first device couples to a second device, that connection may be through a direct connection, or through an indirect connection via other devices and connections.

Referring to fig. 1, fig. 1 is a schematic diagram of a display device 10 according to an embodiment of the invention. As shown in fig. 1, the display apparatus 10 of the present embodiment includes a processor 100, a display panel 102 and a storage device 104. Preferably, the processor 100 in the present embodiment can integrate the functions of a central processing unit and/or an image processor, and is coupled to the display panel 102 and the storage device 104, and transmits the related control signals and display data to the display panel 102 and the storage device 104 to provide the frequency signals and the display signals correspondingly. The display panel 102 includes a plurality of pixel units, and can correspondingly display or play back a display data according to a control signal of the processor 100. The storage device 104 stores a program code, and the program code is operable to correct a display brightness of a plurality of pixel units on the display panel 102 according to a control signal of the processor 100. Accordingly, when a manufacturer or a product user finds that at least one horizontal line defect has occurred in one or more pixel units of the display panel 102 of the display apparatus 10, the display brightness of the pixel unit corresponding to the at least one horizontal line defect can be correspondingly corrected by using a correction method provided by the present embodiment, so as to recover the normal display operation of the display apparatus 10.

It should be noted that the embodiment does not limit the mobile electronic product carrying the display device 10, or the display device 10 itself can work independently, in other words, according to different requirements of users or product designers, the display device 10 in the embodiment can work as an accessory device and be integrated into an electronic product (such as a mobile phone, a tablet device, a wearable electronic product, or a notebook computer) to increase the application range of the electronic product, of course, the display device 10 can also be an electronic system (such as a liquid crystal display) and be coupled to an electronic computing system (such as a personal computer or a multimedia device), and correspondingly provide a display operator when the two support to work, which all belong to the scope of the present invention.

Further, the calibration method applied to the display apparatus 10 of the present embodiment can be summarized as a calibration process 20, and is compiled into program codes and stored in the storage device 104, as shown in fig. 2, the calibration process 20 includes the following steps.

Step 200: and starting.

Step 202: it is determined whether there is at least one calibration area on the display panel 102.

Step 204: if the display panel 102 has at least one calibration area, a compensation operation is performed to make the display brightness conform to the predetermined brightness according to the difference between the display brightness of the calibration area and a predetermined brightness.

Step 206: and (6) ending.

After the user starts the display operation of the display device 10, the product yield verification/quality control operation may be performed to correspondingly start the calibration process 20 (i.e., step 200). In step 202, a user can determine whether there is at least one correction area on the display panel 102 by a visual inspection method, i.e., visually inspect whether there is a problem of horizontal line defect in the pixel units of the display apparatus 10. Of course, in another embodiment, the user can also utilize a detection module coupled to the display device 10 to check or detect whether the pixel unit of the display device 10 has a horizontal line defect. Further, the detection module may be used to capture the display brightness of the plurality of pixel units on the display panel 102 to obtain the actual display brightness values of the pixel units for subsequent work.

Preferably, the detecting module in this embodiment can simultaneously refer to a comparison result of an optimal Sample (Golden Sample) to determine whether there is a problem of detecting a horizontal line defect in at least one pixel unit of the display apparatus 10. In other words, since the hardware device corresponding to the best sample (i.e. another defect-free display device) is already the best setup and good product, i.e. the pixel units of the best sample do not include the problem of horizontal line defects, accordingly, the user can work the display device 10 and the best sample at a plurality of gray-scale values simultaneously to obtain a first gray-scale value distribution of the display device 10 and a second gray-scale value distribution of the best sample, and the processor 100 of the display device 10 refers to the difference between the first gray-scale value distribution and the second gray-scale value distribution to determine whether there is at least one calibration region on the display panel 102.

Further, when the processor 100 determines that the difference between the first gray-scale value distribution and the second gray-scale value distribution exceeds a predetermined value, the display device 10 is determined to include at least one calibration area (i.e. at least one pixel unit of the display device 10 has a problem of horizontal line defect). In this case, the correction process 20 of the present embodiment may further perform a positioning operation and a classification operation on one or more pixel units in at least one correction area to determine the severity and related data of the actual defect of one or more pixel units having horizontal line defects in the correction area. Preferably, the positioning operation in this embodiment can determine that the at least one calibration area is located at an absolute position of the display panel 102, and the classifying operation can determine that one or more pixel units in the at least one calibration area are in a clustering mode or a clustering mode, i.e., the classifying operation further determines whether the pixel units are in a scattered distribution or a clustered distribution. Accordingly, the processor 100 further collects the absolute positions and classification data corresponding to one or more pixel units having horizontal line defects in at least one correction region (i.e. determines the pixel units to be in a cluster mode or a scatter mode) for subsequent operations.

In step 204, if the processor 100 determines that there is at least one calibration area on the display panel 102, the processor 100 compares the display brightness of the pixel units in the calibration area with the predetermined brightness to perform a compensation operation to make the display brightness match the predetermined brightness. Preferably, in the embodiment, the processor 100 first collects the absolute positions and classification data of the one or more pixel units with horizontal line defects (i.e. determines the pixel units to be in the clustering mode or the scattering mode) in step 202, and then compares the numerical difference between the display brightness of the one or more pixel units with horizontal line defects and the predetermined brightness to correspondingly determine which way the processor 100 will adopt to perform the compensation operation of the display panel 102, so that the display brightness of the one or more pixel units with horizontal line defects can be restored to the ideal predetermined brightness, thereby correspondingly optimizing the display operation of the display device 10 and correspondingly improving the recycling rate of the product.

In detail, the compensation method in this embodiment includes performing a digital image operation, and the digital image operation includes obtaining a mapping curve of one or more pixel units corresponding to different gray-scale values on at least one correction area, or performing a brightness compensation operation or a color compensation operation for different color gamut spaces, so that the processor 100 can perform the digital image operation to make the display brightness in the at least one correction area conform to the predetermined brightness. Referring to fig. 3, fig. 3 is a schematic diagram of a digital image operation according to an embodiment of the invention. As shown in FIG. 3, the left graph has a solid line C2 indicating an ideal transmittance corresponding to a plurality of normal pixel cells operating at different gray-scale values, and a dashed line C1 indicating an actual transmittance corresponding to a pixel cell in the correction region operating at different gray-scale values. Accordingly, according to the comparison result, it can be correspondingly known that the transmittance of the specific pixel unit with the missing line of the horizontal line in the correction area is higher than that of the pixel unit in normal operation, so that the display brightness generated by the specific pixel unit in the correction area is higher than the predetermined brightness of the pixel unit in normal operation. In this case, the present embodiment can correspondingly perform digital image work to map the original gray-scale value (i.e. the solid line C4 in the right diagram of fig. 3) to the corrected gray-scale value (i.e. the broken line C3 in the other diagram of fig. 3), so that the corrected gray-scale value to be outputted after adjustment will be lower than the original gray-scale value, and one or more pixel units in the corrected area can correspondingly display the normal predetermined brightness.

Referring to fig. 4, fig. 4 is a schematic diagram of another digital image operation according to an embodiment of the invention. As shown in fig. 4, if the gray-scale values correspond to a range of values from 0 to 255, the present embodiment may further simplify and modify the operation manner of the embodiment of fig. 3, that is, the transmittance corresponding to one gray-scale value (e.g., a plurality of measurement points on a dashed line C5 drawn on the left diagram of fig. 4) is measured for every 16 gray-scale values, so as to correspondingly reduce the execution cost required by the calibration method, and the transmittance corresponding to the other unmeasured gray-scale values can be obtained by an interpolation method, so that the complete dashed line C5 drawn on the left diagram of fig. 4 can be obtained, and the other solid line C6 drawn on the left diagram of fig. 4 is the ideal transmittance corresponding to a plurality of normal pixel units under different gray-scale values. In this case, according to the comparison result between the dashed line C5 and the solid line C6, the transmittance of the specific pixel cell having the horizontal line missing line in fig. 4 is 1.5 times higher than that of the pixel cell in normal operation, so that the digital image operation performed in the present embodiment can map the original gray level value (i.e., the solid line C8 in the right image of fig. 4) to the corrected gray level value (i.e., the other dashed line C7 in the right image of fig. 4), so that the corrected gray level value to be outputted after adjustment is lower than the original gray level value, so that the corrected pixel cell or cells in the corrected area can correspondingly display the normal predetermined brightness.

Of course, in other embodiments, if the display device 10 is inspected to further include a plurality of other correction areas that need to be corrected/compensated, and each correction area further includes a problem that a plurality of pixel units are determined to have missing horizontal lines, and the missing horizontal lines of the pixel units are not the same in magnitude, the processor 100 of this embodiment may further refer to and determine the absolute positions and classification data corresponding to the pixel units, so as to apply digital images of different correction/compensation methods to the pixel units, respectively, to perform gray level mapping of different defect degrees, which also belongs to the scope of the present invention, and as for details, reference may be made to the following paragraphs.

In another embodiment, the digital image processing method performed by the processor 100 may also perform brightness compensation or color compensation according to different color gamut spaces, for example, the digital image processing method may perform correction and compensation for RGB color gamut spaces, or may perform correction and compensation for HSV, YCbCr, or other color gamut spaces. In addition, the present embodiment also does not limit the details of the correction and compensation, for example, the above color luminances in the color gamut space may be selected to perform the correction and compensation, or only the specific parameter in the color gamut space HSV, such as the luminance parameter V, may be selected to perform the correction and compensation, or the specific parameter in the color gamut space YCbCr, such as the luminance parameter Y, may be selected to perform the correction and compensation. Of course, other embodiments may select other parameters for the specific color gamut space to perform the correction and compensation operations, and are not intended to limit the scope of the present invention. Moreover, since the visual perception of human eyes refers to the average value of a plurality of imaging parameters in a few spatial frames, if the setting distances corresponding to a plurality of pixel units with horizontal line defects in the correction area are too close and the visual perception of human eyes is discontinuous, in this case, the correction and compensation performed in this embodiment can correspondingly adjust the mapping curves corresponding to the pixel units to correspondingly perform the interpolation/compensation of another curve, which also falls within the scope of the present invention.

In addition, the compensation method in this embodiment further includes performing a Gamma (Gamma) compensation operation to obtain a Gamma setting curve of a specific gray level value on the at least one correction region, and using the Gamma compensation operation to make the display brightness of the one or more pixel units in the at least one correction region conform to the predetermined brightness. Referring to FIG. 5, FIG. 5 is a schematic diagram illustrating an analog gamma compensation operation according to an embodiment of the present invention. As shown in fig. 5, the left diagram of the present embodiment plots a dotted line C5 (i.e., the transmittance curve of a certain pixel cell to be corrected and compensated) and a solid line C6 (i.e., the transmittance curve of an ideal pixel cell) similar to the left diagram of fig. 4, i.e., the transmittance of a specific pixel cell with a horizontal line missing is 1.5 times higher than that of a pixel cell in normal operation. Accordingly, the analog gamma compensation operation provided by the present embodiment refers to a voltage adjustment curve C9 depicted in the right diagram of fig. 5 to correspondingly adjust the voltage value of the specific pixel unit having the horizontal line defect, so that the display brightness of the specific pixel unit having the horizontal line defect in the correction region can be adjusted to the predetermined brightness.

Referring to fig. 6A to 6C, fig. 6A to 6C are schematic diagrams illustrating compensation performed on a display screen according to an embodiment of the invention. In this embodiment. FIG. 6A shows a defect region DL1 occurring in the center of a display frame, i.e., for a NormallyWhite display panel, the defect region DL1 indicates that the pixel cells are under-charged, while for a Normally Black display panel, the defect region DL1 indicates that the pixel cells are over-charged (or that the pixel cells at other locations on the display panel are under-charged). In this case, since the display brightness displayed by the pixel unit with horizontal line defect is higher than the predetermined brightness, accordingly, the present embodiment can correspondingly perform the above-mentioned various correction and compensation operations, and the gray level of the pixel unit with horizontal line defect is correspondingly reduced (as shown in fig. 6B) to a correction region DL2, so as to obtain the display frame after the correction and compensation operations (as shown in fig. 6C), that is, the display frame will include a normal display region DL3, i.e., the display brightness of one or more pixel units in the correction regions on the display panel 102 is restored to the predetermined brightness.

It should be noted that in other embodiments, if the pixel units with horizontal line defects are in the clustering mode and the display brightness of the pixel units deviates from the predetermined brightness by a fixed value, the calibration and compensation operation of the present embodiment determines that the pixel units only include a single defect object, and further, the calibration and compensation operation is performed with reference to a coordinate range of the defect object; if the pixel units with horizontal line defects are in the distributed mode, i.e., it is determined that a plurality of defect objects exist, the embodiment may also refer to the recorded coordinate ranges of the defect objects and the defect degrees included in the defect objects to correspondingly perform the calibration and compensation of the defect objects. Referring to fig. 7, fig. 7 is a schematic diagram of a defect display frame 70 according to an embodiment of the invention, wherein the defect display frame 70 includes a plurality of correction areas, each corresponding to a different defect level. As shown in fig. 7, since the defect display frame 70 already includes a plurality of correction areas corresponding to different defect levels, the processor 100 in the present embodiment correspondingly determines and records the related data of a plurality of defect objects in the defect display frame 70 as the following table 1, so as to clearly illustrate the coordinate ranges and defect levels corresponding to the defect objects, meanwhile, the processor 100 may further compare the difference between the display brightness and the predetermined brightness of the pixel units with different defect degrees to correspondingly determine the correction and compensation operations required for the pixel units of the defect objects, namely, corresponding to different methods 1 to 3, as for detailed working modes of the methods 1 to 3, for example, the mapping curves with different gray scale values may be adjusted, brightness compensation may be performed for different color gamut spaces, or analog gamma compensation may be performed, but the scope of the invention is not limited thereto. In other words, the present embodiment can perform different types of correction and compensation operations on a plurality of defect objects at the same time, so as to shorten the operation time and efficiency required by the correction process, and further cooperate with the design and application of different display devices.

TABLE 1

In short, in the calibration method for the display device 10 in this embodiment, it can be correspondingly determined whether the display device 10 has a calibration area requiring calibration and compensation of the display brightness through the detection module and the visual inspection. If there is a correction region, the present embodiment can correspondingly determine the defect degree, absolute position and classification data of one or more pixel units in the correction regions, so as to correspondingly perform various types of digital image operations and/or analog gamma compensation operations until the display brightness of one or more pixel units having horizontal line defects in the correction regions is restored to the predetermined brightness and the display device 10 can perform normal display operations. Of course, the calibration method for the display device 10 in this embodiment may also be independently presented by using a software, firmware, or hardware, and correspondingly works in combination with other electronic hardware products or display software, and the scope of the invention is not limited thereto. In addition, those skilled in the art may correspondingly add other types of optical image adjustment parameters or visual model adjustment parameters during the calibration process to improve the display performance or application range of the display device 10 in different visual environments, and the like, which also belongs to the scope of the present invention.

In summary, embodiments of the present invention provide a display device and a correction method, which can perform correction and compensation operations on pixel units having horizontal line defects, so as to adjust the display brightness of the pixel units having the horizontal line defects accordingly. Accordingly, the present embodiment can reduce the production cost by recycling the display devices with less serious horizontal line defects, and on the other hand, the present embodiment can also improve the service life of the electronic product bearing the display devices, so as to correspondingly improve the application range and hardware expandability of the electronic products.

The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A calibration method for calibrating a display brightness of a display device, the calibration method comprising:

judging whether a display panel of the display device has at least one correction area, and performing a positioning operation and a classification operation corresponding to the at least one correction area, wherein the classification operation is to judge whether a plurality of pixel units in the at least one correction area are in a clustering mode or a dispersion mode, wherein if the plurality of pixel units are in the clustering mode and the display brightness of the plurality of pixel units deviates from a preset brightness and is a fixed value, the plurality of pixel units are judged to only contain a single defect object, wherein if the plurality of pixel units are in the dispersion mode, the plurality of defect objects are judged to exist, and the correction and compensation operations of the plurality of defect objects are correspondingly performed; and

if the display panel is judged to have the at least one correction area, compensation is carried out according to the difference value between the display brightness of the at least one correction area and the preset brightness to enable the display brightness in the at least one correction area to be consistent with the preset brightness.

2. The calibration method of claim 1, wherein the step of determining whether the at least one calibration area is on the display panel of the display device comprises:

capturing the display brightness by using a detection module; and

according to an optimal sample, working the display device and the optimal sample under a plurality of gray scale values to obtain a first gray scale value distribution of the display device and a second gray scale value distribution of the optimal sample, and determining whether the display panel has at least one correction area by referring to a difference value of the first gray scale value distribution and the second gray scale value distribution.

3. The method of claim 2, wherein the step of determining whether there is at least one calibration area by determining a difference between the first distribution of gray scale values and the second distribution of gray scale values further comprises:

if the difference value between the first gray scale value distribution and the second gray scale value distribution exceeds a preset value, determining that the display device has at least one correction area; and

and performing the positioning work and the classification work corresponding to the at least one correction area.

4. The calibration method of claim 3, wherein the positioning operation is determining that the at least one calibration area is at an absolute position of the display panel.

5. The calibration method of claim 1, wherein the compensation comprises performing a digital image task, the digital image task comprises obtaining a mapping curve corresponding to different gray scale values in the at least one calibration area, performing a brightness compensation task or a color compensation task for different color gamut spaces, and using the digital image task to make the display brightness in the at least one calibration area match the predetermined brightness.

6. The method as claimed in claim 1, wherein the compensation comprises performing a simulation gamma compensation to obtain a gamma curve of a specific gray level in the at least one calibration region, and using the simulation gamma compensation to make the display brightness in the at least one calibration region match the predetermined brightness.

7. A display device, comprising:

a processor for generating a control signal;

a display panel coupled to the processor and including a plurality of pixel units; and

a storage device, coupled to the processor, storing a program code, the program code calibrating a display brightness of the plurality of pixel units according to the control signal, the program code comprising:

judging whether at least one correction area exists on the display panel, and performing positioning work and classification work corresponding to the at least one correction area, wherein the classification work is to judge whether the pixel units in the at least one correction area are in a clustering mode or a dispersion mode, wherein if the pixel units are in the clustering mode and the display brightness of the pixel units deviates from a preset brightness and is a fixed value, the pixel units are judged to only contain a single defect object, and if the pixel units are in the dispersion mode, the pixel units are judged to contain a plurality of defect objects, so that the correction and compensation work of the defect objects is correspondingly performed; and

if the display panel is judged to have the at least one correction area, compensation is carried out according to the difference value between the display brightness and the preset brightness of the pixel units in the at least one correction area so as to enable the display brightness to be consistent with the preset brightness.

8. The display apparatus of claim 7, wherein the step of determining whether the at least one calibration area exists on the display panel further comprises:

capturing the display brightness by using a detection module, wherein the detection module is coupled with the display device; and

according to an optimal sample, the display device and the optimal sample are operated under a plurality of measured gray scale values to obtain a first gray scale value distribution of the display device and a second gray scale value distribution of the optimal sample, and then the difference value of the first gray scale value distribution and the second gray scale value distribution is judged to determine whether at least one correction area exists.

9. The display apparatus of claim 8, wherein the step of determining whether there is at least one calibration area by determining a difference between the first distribution of gray scale values and the second distribution of gray scale values further comprises:

10. The display apparatus according to claim 9, wherein the positioning operation is to determine that the at least one calibration area is at an absolute position of the display panel.

11. The display apparatus according to claim 7, wherein the compensation operation comprises performing a digital image operation, the digital image operation comprises obtaining a mapping curve corresponding to different gray scale values in the at least one calibration area, performing a brightness compensation operation or a color compensation operation for different color gamut spaces, and using the digital image operation to make the display brightness in the at least one calibration area match the predetermined brightness.

12. The display apparatus of claim 7, wherein the compensation comprises performing an analog gamma compensation to obtain a gamma curve of a specific gray level on the at least one calibration region, and using the analog gamma compensation to make the display brightness in the at least one calibration region match the predetermined brightness.