CN111845076B

CN111845076B - Substrate and method for judging pixel printing defects

Info

Publication number: CN111845076B
Application number: CN202010987531.XA
Authority: CN
Inventors: 岳春波; 夏宇飞
Original assignee: Individual
Current assignee: Individual
Priority date: 2020-09-18
Filing date: 2020-09-18
Publication date: 2020-12-29
Anticipated expiration: 2040-09-18
Also published as: CN111845076A

Abstract

The invention relates to the technical field of ink-jet printing, and particularly discloses a substrate for judging pixel printing defects, which comprises a substrate body, wherein a plurality of areas are arranged on the substrate body, a plurality of pixel grooves are arranged in the areas, and the openings of the pixel grooves are the same in size; the heights of the pixel grooves in the same region are the same, and the intervals of the pixel grooves in the same region are the same; the height of the pixel grooves in different regions is different, or the interval of the pixel grooves in different regions is different, or the height of the pixel grooves in different regions is different and the interval of the pixel grooves is different. The pixel substrate provided by the invention judges whether bridging is caused by deviation of drop points by printing on the areas with different pixel groove intervals, and judges whether bridging is caused by overlarge ink jet quantity by printing on the areas with different pixel groove heights, and the provided substrate can quickly judge the cause of bridging defects.

Description

Substrate and method for judging pixel printing defects

Technical Field

The invention relates to the technical field of ink-jet printing, in particular to a substrate and a method for judging pixel printing defects.

Background

As shown in fig. 1-2, in a prior art OLED or quantum dot inkjet printing process, liquid droplets are ejected through a piezojet 105 into pixel wells defined by photoresist. In the spray printing process, factors such as process parameters and mechanical precision can cause the defects of non-uniform pixel brightness, color mixing and the like in the final device, and most of the defects can be observed by a CCD high-speed camera after printing to obtain a conclusion. As shown in FIG. 3, the common defects include three types of defects, i.e., dot scattering, dot non-wetting and bridging, in which the non-wetting defect is caused by poor wettability between the inkjet ink and the bottom surface of the pixel slot, the dot scattering defect is caused by the deviation of the drop landing point, however, the bridging defect is difficult to determine, and the deviation of the inkjet landing point or the large volume of the drop ejected into the pixel slot can cause the bridging defect between adjacent pixels

How to rapidly and accurately judge the cause of the bridging defect is of great significance.

Disclosure of Invention

A first object of the present invention is to provide a substrate for determining a pixel printing defect, which can quickly and accurately determine the cause of the generation of a bridging defect.

In order to achieve the purpose, the technical scheme provided by the invention is as follows: a substrate for judging pixel printing defects comprises a substrate body, wherein a plurality of areas are arranged on the substrate body, a plurality of pixel grooves are formed in the areas, and the sizes of openings of the pixel grooves are the same;

the heights of the pixel grooves in the same region are the same, and the intervals of the pixel grooves in the same region are the same;

the heights of the pixel grooves in different regions are different, or the intervals of the pixel grooves in different regions are different, or the heights of the pixel grooves in different regions are different and the intervals of the pixel grooves are different.

Further, the substrate body is provided with a first area, a second area and a third area, and a plurality of pixel grooves are respectively arranged in the first area, the second area and the third area;

the height of the pixel grooves of the first area is the same as that of the pixel grooves of the second area, and the spacing distance of the pixel grooves of the first area is greater than that of the pixel grooves of the second area;

the pixel groove spacing distance of the first area is the same as that of the third area, and the pixel groove height of the first area is smaller than that of the third area.

Furthermore, the second region is divided into a plurality of second sub-regions, the second sub-regions have a predetermined distance therebetween, and the pixel slots of each second sub-region have different intervals and are sequentially decreased in a direction away from the first region;

the third area is divided into a plurality of third sub-areas, a preset distance is reserved between the third sub-areas, and the height of the pixel groove of each third sub-area is different and is sequentially increased in a direction away from the first area.

Further, the substrate body comprises 1800 × 1800 pixel grooves, the first region comprises 400 × 1800 pixel grooves, the pixel groove interval of the first region is 40um, and the height is 1 um;

the second area comprises three second sub-areas, each second sub-area comprises 400 x 800 pixel slots, the height of each pixel slot of each second sub-area is 1um, and the intervals of the pixel slots of the three second sub-areas are respectively 30um, 20um and 15 um;

the third area includes three third subregion, every the third subregion includes 400 x 800 pixel groove, the pixel groove interval of third subregion all is 40um, and is three the pixel groove height of third subregion is 1.3um, 2um and 3um respectively.

Furthermore, the base plate body is provided with a positioning cross target point.

The second object of the present invention is to provide a method for determining pixel printing defects, comprising:

and printing on the substrate, and judging pixel printing defects according to pixel printing results.

Further, the method for judging pixel printing defects comprises the following steps:

and printing on the first printing area of the substrate, if the bridging phenomenon occurs in the printing result, printing on the first printing area in an interlaced printing mode, and if the bridging phenomenon occurs in the printing result, judging that the printing defect is that the drop landing point has deviation.

Further, if the bridging phenomenon does not occur in the printing result of the interlaced printing mode, selecting a second printing area on the substrate for interlaced printing, if the bridging phenomenon occurs in the printing result, judging that the printing defect is that the drop point of the liquid drop has deviation,

the pixel groove height of the second printing area is the same as that of the first printing area, and the pixel groove interval of the second printing area is smaller than that of the first printing area;

and repeatedly selecting a printing area with a smaller pixel groove interval than that of the previous printing area for interlaced printing until the printing result has a bridging phenomenon or until the pixel groove interval of the selected printing area is minimum.

Further, when the printing area with the minimum pixel slot interval is subjected to interlaced printing, if the printing result does not have the bridging phenomenon, a third printing area is selected for printing, if the printing result does not have the bridging phenomenon, the printing defect is judged to be that the ink jet quantity is overlarge,

the pixel groove height of the third printing area is larger than that of the first printing area, and the pixel groove interval of the third printing area is the same as that of the first printing area.

Further, if the bridging phenomenon occurs in the result of printing in the third printing area, selecting a printing area with a height larger than that of the pixel groove of the third printing area for printing until the bridging phenomenon does not occur in the printing result or until the height of the pixel groove of the selected printing area is the maximum.

The invention has the beneficial effects that:

the pixel substrate provided by the invention is provided with a plurality of areas with different pixel groove intervals and areas with different pixel groove heights, whether bridging is caused by deviation of drop falling points is judged by printing on the areas with different pixel groove intervals, whether bridging is caused by overlarge ink jet quantity is judged by printing on the areas with different pixel groove heights, all defects in printing can be inspected by the provided substrate, and the reasons for generating bridging defects can be quickly judged.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the structures shown in the drawings without creative efforts.

FIG. 1 is a schematic illustration of an ink jet printing process;

FIG. 2 is a top view of an ink jet printing process;

FIG. 3 is a schematic view of an inkjet printing defect;

FIG. 4 is a schematic view of an inkjet printed bridging defect;

FIG. 5 is a schematic diagram illustrating a determination of a drop point deviation;

FIG. 6 is an embodiment of a substrate of the present invention;

FIG. 7 is a schematic diagram of a substrate design definition for pixel printing according to an embodiment of the invention;

FIG. 8 is a flowchart illustrating a defect determination method according to an embodiment of the present invention;

FIG. 9 is a schematic view of interlaced printing according to an embodiment of the present invention;

FIG. 10 is a schematic diagram of a bridging defect in interlaced printing according to an embodiment of the present invention;

fig. 11 is a diagram illustrating a fifth area pixel slot according to an embodiment of the invention.

Reference numerals:

100-a substrate; 101 pixel slots; 102-a cross target; 103-Bank; 104-ink droplets; 105-a spray head;

200-a first region; 300-a second region; 400-a third region; 500-a fourth region; 600-a fifth region; 700-sixth zone; 800-seventh area.

Detailed Description

In ink-jet printing, the offset of the position of the drop point or the large volume of the ink drop 104 ejected into the pixel slot can cause the bridging defect between adjacent pixels, as shown in fig. 4. If the bridging defect is caused by a deviation in drop placement, the method of analyzing the drop placement of a liquid in a typical ink jet printing process typically prints on a flat, but non-pixellated, photoresist material and compares the actual drop placement to the desired placement, as shown in FIG. 5. However, this method is limited by the irregularity of the drop profile due to the cleanliness and roughness of the photoresist material surface, and when this occurs, the reliability of the scheme for identifying the drop profile using the algorithm of CCD vision recognition is affected. If it is inferred that the cause of bridging is excessive ink volume, the detection scheme generally employed is by reducing the number of ink drops, however, when the liquid volume is reduced by the amount of one or more drops, the problem of bridging still occurs, and it is difficult to identify the cause of bridging.

In order to solve the above problems, the present invention provides an embodiment of a substrate for determining a pixel printing defect, and an embodiment of a method for determining a pixel printing defect using the substrate.

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

It should be noted that all the directional indicators (such as up, down, left, right, front, and rear … …) in the embodiment of the present invention are only used to explain the relative position relationship between the components, the movement situation, etc. in a specific posture (as shown in the drawing), and if the specific posture is changed, the directional indicator is changed accordingly.

It will also be understood that when an element is referred to as being "secured to" or "disposed on" another element, it can be directly on the other element or intervening elements may also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present.

In addition, the descriptions related to "first", "second", etc. in the present invention are for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicit indication of the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of the feature. In addition, technical solutions between various embodiments may be combined with each other, but must be realized by a person skilled in the art, and when the technical solutions are contradictory or cannot be realized, such a combination should not be considered to exist, and is not within the protection scope of the present invention.

Fig. 6 is an embodiment of a substrate for determining a pixel printing defect according to the present invention.

Referring to fig. 6, the display device specifically includes a substrate 100, the substrate 100 has 1800 × 1800 pixel slots 101, the pixel slots on the substrate 100 are divided into seven pixel regions, which are a first region 200, a second region 300, a third region 400, a fourth region 500, a fifth region 600, a sixth region 700, and a seventh region 800.

Wherein the height of the pixel grooves 101 in the second, third and

fourth regions

300, 400 and 500 is the same as the height of the pixel grooves 101 of the first region 200, with different intervals. The second area 300, the third area 400 and the fourth area 500 are used for determining whether the bridging defect is caused by deviation of the drop landing point. In order to improve the resolution of detecting the drop landing deviation, a plurality of areas with different pixel densities are designed for accurately judging the tolerance limit of the existing printing landing deviation.

If the defect of bridging is that the total volume of the ejected ink is larger, the substrate with the same pixel density and pixel groove opening area as the original substrate can be designed, but the depth of the pixel groove is larger, so that more ink can be borne, and the risk of bridging is reduced. For example, the intervals of the pixel grooves 101 of the fifth, sixth, and

seventh regions

600, 700, and 800 are the same as those of the pixel grooves 101 of the first region 200, and are different in height. The fifth area 600, the sixth area 700, and the seventh area 800 are used to determine whether the bridging defect is caused by an excessive ink ejection amount.

Specifically, the number of the pixel grooves 101 in the first region 200 is 400 × 1800, the height of the pixel grooves 101 is 1um, and the interval between the pixel grooves 101 is 40 um; the number of the pixel grooves 101 in the second area 300 is 400 × 800, the height of the pixel grooves 101 is 1um, and the interval between the pixel grooves 101 is 30 um; the number of the pixel grooves 101 in the third area 400 is 400 × 800, the height of the pixel grooves 101 is 1um, and the interval between the pixel grooves 101 is 20 um; the number of the pixel grooves 101 in the fourth area 500 is 400 × 800, the height of the pixel grooves 101 is 1um, and the interval between the pixel grooves 101 is 15 um; the number of the pixel grooves 101 in the fifth area 600 is 400 × 800, the height of the pixel grooves 101 is 1.3um, and the interval between the pixel grooves 101 is 40 um; the number of the pixel grooves 101 in the sixth area 700 is 400 × 800, the height of the pixel grooves 101 is 2um, and the interval between the pixel grooves 101 is 40 um; the seventh region 800 has 400 × 800 pixel grooves 101, a height of the pixel grooves 101 is 3um, and the pixel grooves 101 are spaced at intervals of 40 um. The difference between the respective regions is the height of the pixel groove 101 and the interval between the pixel grooves along the short axis direction.

As used herein, pixel groove spacing and pixel groove height are defined as shown in fig. 7, and the pixel grooves 101 are surrounded by banks 103, where a and C are the dimensions of the pixel grooves 101, a is the width of the pixel grooves 101, and C is the length of the pixel grooves 101. B and D are the periods in which the pixels repeat in the X & Y directions, and the height of the pixel groove 101 is defined as E in the figure as the height of Bank 103. The interval is the value of B minus the value of A in the figure, i.e. the value of B-A is the interval.

In one embodiment, the substrate 100 is rectangular, and the four corners of the substrate 100 are respectively provided with positioning cross target points 102 for positioning.

In one embodiment, the substrate 100 may be cleaned and reused, and may be stored in a nitrogen environment for a long period of time without degradation, and the photoresist material should be selected to be the same as a substrate in a normal process.

The embodiment of the substrate 100 is used to determine the cause of the defect, and an embodiment of a defect determining method is provided, and a specific flow is shown in fig. 8.

Referring to fig. 8, the method specifically includes the following steps:

10. interlaced printing defect judgment

The regular printing is performed on the first area 200, if the bridging phenomenon appears in the printing result as shown in fig. 4, the first area 200 is printed again by adopting an interlaced printing mode, the interlaced printing mode is as shown in fig. 9, the printing is performed at intervals of two rows of pixel slots, if the bridging phenomenon appears in the printing result, namely, the ink drops 104 also exist in the adjacent pixel slots of the pixel slot to be printed originally, as shown in fig. 10, the printing defect is determined to be that the drop landing point has deviation.

In the present embodiment, the printing method of two lines is selected, but the method is not limited to two lines, and in other embodiments, the number of lines may be selected as needed.

20. Selecting a printing area with lower density to carry out interlaced printing to judge defects

If no bridging occurs in the interlaced printing in the first area 200, the deviation of the drop landing point may be small enough to cause the drop 104 to land in the adjacent pixel slot, in which case the substrate with higher pixel density and unchanged pixel slot area can be used, and the interlaced printing still is used to determine the defect. That is, the second area 300 having a pixel density greater than that of the first area 200 is selected for interlaced printing. If the bridging phenomenon appears in the printing result, the printing defect is judged to be that the drop points have deviation, and if the bridging phenomenon does not appear in the printing result, the third area 400 with the density higher than that of the second area 300 is continuously selected for carrying out interlaced printing.

The design of multiple areas with different pixel densities can improve the resolution of detecting the drop landing offset and can be used for accurately judging the tolerance limit of the printing drop landing offset.

30. Selecting printing areas with different pixel groove capacities to judge defects by printing

If the ink drop 104 in the adjacent pixel slot is not found even if the pixel density is changed for multiple times for interlaced printing, that is, the bridging phenomenon does not occur, then it can be preliminarily determined that the bridging reason is not the problem of drop landing deviation. In this embodiment, if the fourth area 500 is selected for interlaced printing, the bridging phenomenon does not occur, and it can be preliminarily determined that the bridging cause is not the problem of droplet landing deviation.

Therefore, the defect judgment is performed by selecting the area having the same density as the first area 200 but different height and capable of accommodating more ink droplets 104. For example, the fifth region 600 is selected, and as shown in fig. 11, the pixel density and the opening area of the pixel groove of the fifth region 600 are the same as those of the first region 200, but the depth of the pixel groove is larger. If printing is normal on the fifth area 600 shown in fig. 11, no problem of bridging is found, and therefore it can be finally determined that bridging is caused by an excessively large ink ejection amount. To improve the resolution of the maximum ink volume of the detection pixel well, a plurality of regions with different pixel well depths, such as the sixth region 700 and the seventh region 800, may be designed on the detection substrate.

In summary, the embodiments of the present invention perform interlaced printing on a plurality of regions with different pixel densities to determine whether bridging is caused by a deviation of drop points, and perform printing on a plurality of regions with different pixel groove heights to determine whether bridging is caused by an excessive ink ejection amount.

The above description is only a preferred embodiment of the present invention, and is not intended to limit the scope of the present invention, and all modifications and equivalents of the present invention, which are made by the contents of the present specification and the accompanying drawings, or directly/indirectly applied to other related technical fields, are included in the scope of the present invention.

Claims

1. A substrate for judging pixel printing defects is characterized by comprising a substrate body, wherein a plurality of areas are arranged on the substrate body, a plurality of pixel grooves are arranged in the areas, and the sizes of openings of the pixel grooves are the same;

2. A substrate for judging pixel printing defects according to claim 1, wherein the substrate body has a first region, a second region and a third region, and the first region, the second region and the third region have a plurality of pixel grooves therein, respectively;

3. The substrate according to claim 2, wherein the second area is divided into a plurality of second sub-areas, the second sub-areas have a predetermined distance therebetween, and the pixel slots of each second sub-area are spaced at different intervals and decrease in sequence in a direction away from the first area;

4. The substrate according to claim 3, wherein the substrate body comprises 1800 × 1800 pixel grooves, the first region comprises 400 × 1800 pixel grooves, the pixel groove interval of the first region is 40um, and the height is 1 um;

5. The substrate for judging pixel printing defects according to claim 1, wherein the substrate body is provided with a positioning cross target point.

6. A method of determining pixel print defects, comprising:

printing on the substrate according to any one of claims 1 to 5, wherein the pixel printing defect is judged based on the pixel printing result.

7. The method of claim 6, wherein the method of determining pixel print defects comprises:

8. The method according to claim 7, wherein if no bridging phenomenon occurs in the interlaced printing mode, the second printing area on the substrate is selected for interlaced printing, and if a bridging phenomenon occurs in the printing result, it is determined that the printing defect is a deviation in drop landing point,

9. The method according to claim 8, wherein when the printing area with the minimum pixel slot interval is interlaced, the third printing area is selected for printing if no bridging phenomenon occurs in the printing result, and if no bridging phenomenon occurs in the printing result, the printing defect is determined to be an excessive ink ejection amount,

10. The method according to claim 9, wherein if the bridging phenomenon occurs in the third printing area, selecting a printing area with a height greater than the pixel groove height of the third printing area for printing until the bridging phenomenon does not occur in the printing result or until the pixel groove height of the selected printing area is the maximum.