Continuous laser-based printed oled defect detection and compensation apparatus and method

Abstract

The present application relates to the field of printed electronics, and particularly relates to a continuous laser-based printed OLED defect detection and compensation system and method, comprising a main control module, a main moving module, a secondary moving module, a timing processing module, a piezoelectric control module, an ink supply module, an RGB main piezoelectric nozzle, an RGB compensation nozzle, a laser emitter, a photoelectric receiver and an OLED pixel substrate. Through the ink droplet backlight shielding effect of continuous laser and the pulse high-low level sequence formed by photoelectric conversion, the number and state of ink droplet ejection are recorded at high speed. Through the standard comparison counter and multiple pulse quantity counters in the timing processing module, the precise sequencing and positioning of broken ink droplets are realized. Through the unique coordinate information of the pixels on the OLED pixel substrate, the sequence binding of the defective pixels and the broken ink droplets is realized. Through the secondary moving module and the RGB compensation nozzle, the compensation process of the defective pixels is completed. The main printing process and the defect detection and compensation process are carried out simultaneously, which greatly improves the preparation efficiency of printed OLED.

Description

Technical Field

[0001] This invention relates to the field of printed electronics technology, and in particular to a device and method for detecting and compensating defects in printed OLEDs based on continuous laser. Background Technology

[0002] Today, display technologies are rapidly evolving, with OLED technology becoming a hot topic in the industry. However, due to the immaturity and instability of the manufacturing process, OLED-related products are too expensive and have insufficient production volume, resulting in a significant panel shortage that fails to meet market demand. Currently, there are two main manufacturing processes for OLED panels: vapor deposition and inkjet printing, with vapor deposition being the primary method for OLED panel production. When using vapor deposition to manufacture the organic light-emitting layer, a vacuum device is required. Solid organic raw materials are added to this device, then heated and vaporized, before re-condensing at a designated substrate location to form the desired OLED organic light-emitting layer. Inkjet printing of OLEDs works differently. It primarily uses a solvent to dissolve the OLED organic material, which is then directly sprayed onto the substrate surface through high-precision nozzles to form an RGB organic light-emitting layer. Undoubtedly, inkjet printing, as a contactless, pressureless, and maskless technology, can precisely spray very small droplets (with a volume of picoliters or femtoliters) onto the desired location. After the solvent evaporates, it dries and solidifies to form a thin film, making it easy to create display devices with extremely high resolution, especially advantageous when processing large-size panels.

[0003] Compared to traditional vapor deposition technology, inkjet printing technology for OLEDs has significant advantages. However, current inkjet printing technology is limited by manufacturing process defects and cannot be widely used in OLED production lines. A crucial reason for this is the lack of guaranteed stability during the printing process. Unlike vapor deposition, inkjet printing typically involves calibrating the printhead before printing. However, the printhead status cannot be monitored during printing. If a printhead malfunctions and becomes clogged, causing ink interruption, it affects not only a single pixel but also a column or even multiple columns of pixels, resulting in numerous empty pixels and pixel clusters, leading to low yield rates for printed OLED devices.

[0004] Therefore, it is necessary to develop a system for detecting and compensating defects in printed OLEDs, which can be used to quickly print large-size OLED panels and fill in vacant pixels and pixel cluster defects that affect device performance during the printing process, in order to meet the requirements of high-quality printing. Summary of the Invention

[0005] To address the aforementioned problems, this invention provides a device and method for detecting and compensating defects in printed OLEDs based on continuous laser.

[0006] In a first aspect, this invention provides a continuous laser-based printed OLED defect detection and compensation system, comprising: a main control module, a main moving module, a secondary moving module, a timing processing module, a piezoelectric control module, an ink supply module, an RGB main piezoelectric printhead, an RGB compensation printhead, a laser emitter, a photodetector, and an OLED pixel substrate.

[0007] The main control module is electrically connected to the main moving module, the secondary moving module, the timing processing module, the piezoelectric control module, and the ink supply module, respectively.

[0008] The RGB main piezoelectric printhead, the laser emitter, and the photoelectric receiver are mounted on the main moving module. The main moving module moves synchronously in the Y-axis direction, the RGB main piezoelectric printhead performs reciprocating printing motion in the X-axis direction, and the RGB compensation printhead is mounted on the secondary moving module and moves freely in the XYZ three-axis directions.

[0009] The ink supply module supplies ink to the RGB main piezoelectric printhead and the RGB compensation printhead, and the piezoelectric control module drives the RGB main piezoelectric printhead and the RGB compensation printhead to eject ink droplets onto the OLED pixel substrate;

[0010] The RGB main piezoelectric nozzle includes m RGB monochrome nozzles, the RGB compensation nozzle has multiple monochrome compensation nozzles, the laser emitter includes m laser light sources, each laser light source is used to emit one laser beam, and the photoelectric receiver includes m photoelectric sensing heads, each photoelectric sensing head is used to receive the laser beam emitted by the corresponding laser light source. The spatial arrangement of the RGB monochrome nozzles, the laser light sources and the photoelectric sensing heads is corresponding.

[0011] The timing processing module is electrically connected to the photoelectric receiver. The timing processing module includes one standard comparator counter and m pulse count counters. The pulse count counter number of each pulse count counter is bound to a corresponding RGB monochrome nozzle. Both the standard comparator counter and the pulse count counters perform an incrementing operation, where m is a positive integer greater than 0.

[0012] The main control module controls the main moving module to drive the RGB main piezoelectric printhead to perform a single printing motion along the positive X-axis. The piezoelectric control module outputs a laser amplitude modulation signal to drive the RGB monochrome nozzles of the RGB main piezoelectric printhead to eject ink droplets. During the droplet fall, the laser light emitted by the laser source is intermittently blocked. The photoelectric sensor converts the received intermittent laser light into pulse high and low level signals and transmits the pulse high and low level signals to the timing processing module. The standard comparison counter in the timing processing module continuously performs an incrementing operation, and the incrementing frequency is synchronized with the laser amplitude modulation signal. The m-th pulse count counter increments when it detects the arrival of the rising edge. After each incrementing operation, the standard comparison value is compared with the pulse count. The counter value of the device is compared. When the standard comparison value and the count value are not equal, it is determined that there is an ink jet interruption. The pulse counter number of the current pulse count counter and the standard comparison value are recorded and stored in the register of the timing processing module. The standard comparison value is assigned to the count value. The timing processing module continuously transmits the pulse counter number and the standard comparison value in the register to the main control module. The main control module determines the position information of the defective pixel based on the numerical information of the pulse counter number and the standard comparison value. It controls the secondary moving module to move the corresponding monochrome compensation printhead of the RGB compensation printhead above the defective pixel. The piezoelectric control module drives the monochrome compensation printhead to eject ink droplets into the defective pixel, completing the defective pixel compensation process.

[0013] As an optional solution, the photoelectric sensor outputs a low level when it senses laser light and a high level when there is no laser light.

[0014] As an optional solution, the RGB compensation nozzle includes three monochrome compensation nozzles.

[0015] As an optional approach, each pixel pit coordinate information on the OLED pixel substrate has a unique standard comparison value and a corresponding count value. The count value is divided by three and the remainder is taken. If the remainder is 1, the defective pixel color is red (R); if the remainder is 2, the defective pixel color is green (G); and if the remainder is 0, the defective pixel color is blue (B).

[0016] Secondly, embodiments of the present invention provide a method for detecting and compensating defects in printed OLEDs based on continuous laser, applied to the aforementioned system for detecting and compensating defects in printed OLEDs based on continuous laser, comprising:

[0017] The main control module controls the main moving module to drive the RGB main piezoelectric printhead to perform a single printing motion along the positive X-axis. The piezoelectric control module outputs a laser amplitude modulation signal to drive the RGB monochrome nozzle of the RGB main piezoelectric printhead to eject ink droplets.

[0018] During the ink droplet's descent, the laser beam emitted by the laser source is intermittently blocked. The photoelectric sensor converts the received intermittent laser beams into pulse high and low level signals and transmits these signals to the timing processing module. A standard comparator counter in the timing processing module continuously increments, with the increment frequency synchronized with the laser amplitude modulation signal. The m-th pulse count counter increments upon detecting a rising edge. After each increment, the standard comparator counter compares its value with the count value of the pulse count counter.

[0019] When the standard comparison value and the count value are not equal, it is determined that there is an ink jet interruption. The pulse counter number of the current pulse quantity counter and the standard comparison value are recorded and stored in the register of the timing processing module, and the standard comparison value is assigned to the count value.

[0020] The timing processing module continuously transmits the pulse counter sequence number and the standard comparison value in the register to the main control module. The main control module determines the position information of the defective pixel based on the numerical information of the pulse counter sequence number and the standard comparison value, and controls the secondary moving module to move the corresponding monochrome compensation printhead of the RGB compensation printhead above the defective pixel. The piezoelectric control module drives the monochrome compensation printhead to eject ink droplets into the defective pixel, thus completing the compensation process of the defective pixel.

[0021] As an optional solution, it also includes:

[0022] When the standard comparison value and the count value are equal, the repeated increment and comparison operation continues.

[0023] Compared with the prior art, the present invention can achieve the following beneficial effects:

[0024] This invention provides a continuous laser-based printed OLED defect detection and compensation system and method, comprising: a main control module, a main moving module, a secondary moving module, a timing processing module, a piezoelectric control module, an ink supply module, an RGB main piezoelectric printhead, an RGB compensation printhead, a laser emitter, a photodetector, and an OLED pixel substrate. Through the ink droplet backlight blocking effect of the continuous laser and the pulse high and low level sequence formed by photoelectric conversion, high-speed recording of the number and state of ink droplet ejection is achieved. Through a standard comparison counter and multiple pulse count counters within the timing processing module, and with the aid of a simplified and efficient timing algorithm, accurate sorting and positioning of interrupted ink droplets are achieved. Through the unique coordinate information of pixels on the OLED pixel substrate, the sequence binding of defective pixels with interrupted ink droplets is realized. The compensation process for defective pixels is completed through the secondary moving module and the RGB compensation printhead. The main printing process and the defect detection and compensation process are performed simultaneously, greatly improving the efficiency of printed OLED fabrication. Attached Figure Description

[0025] Figure 1 This is a schematic diagram of the structure of the printed OLED defect detection and compensation system based on continuous laser in an embodiment of the present invention;

[0026] Figure 2 This is a schematic diagram of the RGB main piezoelectric nozzle of the printed OLED defect detection and compensation system based on continuous laser in an embodiment of the present invention;

[0027] Figure 3 This is a schematic diagram of the RGB compensation nozzle of the continuous laser-based printed OLED defect detection and compensation system in an embodiment of the present invention.

[0028] Figure 4 This is a schematic diagram of the laser emitter in the continuous laser-based printed OLED defect detection and compensation system in an embodiment of the present invention.

[0029] Figure 5 This is a schematic diagram of the photoelectric receiver of the printed OLED defect detection and compensation system based on continuous laser in an embodiment of the present invention;

[0030] Figure 6 This is a schematic diagram of the ink droplet ejection process and pulse signal generation of the continuous laser-based printed OLED defect detection and compensation system in an embodiment of the present invention.

[0031] Figure 7 This is a timing analysis diagram of the printed OLED defect detection and compensation system based on continuous laser in an embodiment of the present invention;

[0032] Figure 8 This is a schematic diagram of the printing direction of the OLED printed substrate in the continuous laser-based OLED defect detection and compensation system in an embodiment of the present invention.

[0033] Figure 9 This is a schematic diagram of defect pixel localization in a continuous laser-based printed OLED defect detection and compensation system according to an embodiment of the present invention.

[0034] Figure 10 This is a schematic flowchart of the printed OLED defect detection and compensation method based on continuous laser in an embodiment of the present invention.

[0035] Figure label:

[0036] Main control module 1, main moving module 2, secondary moving module 3, timing processing module 4, piezoelectric control module 5, ink supply module 6, RGB main piezoelectric printhead 7, RGB compensation printhead 8, laser emitter 9, photoelectric receiver 10, OLED pixel substrate 11, RGB monochrome nozzle 71, monochrome compensation printhead 81, laser beam 91, laser light source 92, RGB pixel pit 100, photoelectric sensor head 101. Detailed Implementation

[0037] In the following description, embodiments of the invention will be described with reference to the accompanying drawings. In the description below, the same modules are denoted by the same reference numerals. Where the same reference numerals are used, their names and functions are also the same. Therefore, their detailed description will not be repeated.

[0038] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and do not constitute a limitation thereof.

[0039] In the description of this invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0040] Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance. Similarly, words such as "a," "one," or "the" do not indicate a quantity limitation but rather that at least one exists. Words such as "including" or "contains" mean that the element or object preceding the word covers the element or object listed after the word and its equivalents, without excluding other elements or objects. Words such as "connected" or "linked" are not limited to physical or mechanical connections but can include electrical connections, whether direct or indirect.

[0041] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances. Furthermore, the technical features involved in the different embodiments of this invention described below can be combined with each other as long as they do not conflict with each other.

[0042] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0043] Combination Figure 1 As shown in the figure, this embodiment of the invention provides a printed OLED defect detection and compensation system based on continuous laser, including: a main control module 1, a main moving module 2, a secondary moving module 3, a timing processing module 4, a piezoelectric control module 5, an ink supply module 6, an RGB main piezoelectric printhead 7, an RGB compensation printhead 8, a laser emitter 9, a photodetector 10, and an OLED pixel substrate 11. The main control module 1 is electrically connected to the main moving module 2, the secondary moving module 3, the timing processing module 4, the piezoelectric control module 5, and the ink supply module 6.

[0044] The main control module 1 employs a controller, which is a master command device that can control the starting, speed regulation, braking, and reversing of the motor by changing the wiring of the main circuit or control circuit and changing the resistance value in the circuit according to a predetermined sequence. It consists of a program counter, instruction register, instruction decoder, timing generator, and operation controller. It is the "decision-making body" that issues commands, that is, it coordinates and directs the operation of the entire computer system. It can be a central processing unit or a field-programmable gate array (FPGA), with no limitation on which.

[0045] Combination Figure 2 and 3 As shown, the main moving module 2 is used to perform ink dispensing operations on the OLED pixel substrate 11. It is a movable mechanism that can be controlled by a servo motor. The RGB main piezoelectric printhead 7, laser emitter 9, and photodetector 10 are mounted on the main moving module 2. The main moving module 2 moves synchronously in the Y-axis direction, and the RGB main piezoelectric printhead 7 performs reciprocating printing motion in the X-axis direction. The RGB compensation printhead 8 is mounted on the secondary moving module 3 and moves freely in the XYZ axes. The secondary moving module 3 can also be driven by a servo motor to enable the RGB compensation printhead 8 to move freely in the XYZ axes. It should be noted that the main moving module 2 and the secondary moving module 3 can be selected as needed, and the structure is not limited.

[0046] The ink supply module 6 can supply ink to the RGB main piezoelectric printhead 7 and the RGB compensation printhead 8 through pipelines to ensure the continuity of ink droplet ejection. The piezoelectric control module 5 can drive the RGB main piezoelectric printhead 7 and the RGB compensation printhead 8 to eject ink droplets into the RGB pixel pits 100 of the OLED pixel substrate 11. The piezoelectric control module 5 can be made of piezoelectric ceramic. It should be noted that the main moving module 2 and the secondary moving module 3 can be selected as needed, and the structure is not limited.

[0047] Combination Figure 2 and Figure 3 As shown, specifically, the RGB main piezoelectric printhead 7 includes m RGB monochrome nozzles 71, where m is a positive integer greater than 0. Each RGB monochrome nozzle 71 corresponds to ejecting ink droplets of RGB color. The RGB compensation printhead 8 has multiple monochrome compensation printheads 81, which are used to compensate for defective pixels. In some embodiments, the RGB compensation printhead 8 may include three monochrome compensation printheads 81.

[0048] Combination Figure 4 and Figure 5As shown, the laser emitter 9 and photodetector 10 are used to detect the falling of ink droplets. The laser beam 91 emitted by the laser emitter 9 illuminates the photodetector 10. During the falling of the ink droplet, the laser beam 91 is intermittently blocked. At this time, the photodetector 10 can generate pulse high and low level signals. The number of laser emitters 9, photodetectors 10 and RGB monochrome nozzles 71 corresponds. Specifically, the laser emitter 9 includes m laser light sources 92, each laser light source 92 is used to emit one laser beam 91. The photodetector 10 includes m photosensitive heads 101, each photosensitive head 101 is used to receive the laser beam 91 emitted by the corresponding laser light source 92. The spatial arrangement of the RGB monochrome nozzles 71, laser light sources 92 and photosensitive heads 101 corresponds. Each group consists of one laser emitter 9 and one photosensitive head, and there are a total of m groups, which can detect the ink droplets of the m RGB monochrome nozzles 71 respectively.

[0049] Combination Figure 6 As shown, in one embodiment, the photoelectric sensor 101 outputs a low level when it senses the laser light 91 and a high level when there is no laser. The ink droplets ejected by the RGB monochrome nozzle 71 intermittently block the laser light 91 emitted by the laser light source 92 during their fall, thus forming a pulse high and low level signal.

[0050] Combination Figure 8 As shown, to further determine the ink droplet dripping situation, the timing processing module 4 is electrically connected to the photoelectric receiver 10. The timing processing module 4 includes one standard comparator counter and m pulse count counters. The pulse count counter number of each pulse count counter is bound to a corresponding RGB monochrome nozzle 71. Both the standard comparator counter and the pulse count counters perform an incrementing operation. The standard comparator counter number is denoted as CNT_Num 0, and the count value of the standard comparator counter is denoted as CNT_0. The pulse count counter number of the mth pulse count counter is denoted as CNT_Num m, and the count value of the mth pulse count counter is denoted as CNT_m. The pulse count counter number of each pulse count counter is bound to an RGB monochrome nozzle 71.

[0051] Combination Figure 8 and Figure 9As shown, during OLED printing defect detection and compensation, the main control module 1 controls the main moving module 2 to drive the RGB main piezoelectric nozzle 7 to perform a single printing motion along the positive X-axis. The piezoelectric control module 5 outputs a laser amplitude modulation (PZT) signal to drive the RGB monochrome nozzle 71 of the RGB main piezoelectric nozzle 7 to eject ink droplets into the RGB pixel pit 100. During the droplet's fall, the laser beam 91 emitted by the laser source is intermittently blocked. The photoelectric sensor converts the received intermittent laser beam 91 into pulse high and low level signals and transmits the pulse high and low level signals to the timing processing module 4. The standard comparator counter in the timing processing module 4 continuously performs an incrementing operation, and the incrementing frequency is synchronized with the laser amplitude modulation signal. The m-th pulse count counter performs an incrementing operation when it detects the arrival of the rising edge. The standard comparator counter (the standard comparator counter number is defined as CNT_Num) 0) After each increment operation, the standard comparison value (defined as CNT_0) is compared with the count value (defined as CNT_m) of the pulse count counter (the pulse count counter number is defined as CNT_Num m). If the standard comparison value (CNT_0) and the count value (CNT_m) are not equal (i.e., CNT_0 ≠ CNT_m), it is determined that there is an ink jet interruption. The current pulse count counter number (CNT_Num m) and the standard comparison value (CNT_0) are recorded and stored in the register of the timing processing module 4. The current standard comparison value (CNT_0) is assigned to the count value (CNT_m). The timing processing module 4 continuously transmits the pulse count counter number (CNT_Num m) and the standard comparison value (CNT_0) in the register to the main control module 1. The main control module 1 calculates the pulse count counter number (CNT_Num m) based on the pulse count counter number (CNT_Num m). The position information of the defective pixel is determined by the numerical information of m) and the standard comparison value (CNT_0). The main control module 1 controls the secondary moving module 3 to move the corresponding monochrome compensation printhead 81 of the RGB compensation printhead 8 to above the defective pixel. The piezoelectric control module 5 drives the monochrome compensation printhead 81 to eject ink droplets into the defective pixel, thus completing the compensation process of the defective pixel.

[0052] This invention provides a continuous laser-based printed OLED defect detection and compensation system, comprising: a main control module, a main moving module, a secondary moving module, a timing processing module, a piezoelectric control module, an ink supply module, an RGB main piezoelectric printhead, an RGB compensation printhead, a laser emitter, a photodetector, and an OLED pixel substrate. Through the ink droplet backlight blocking effect of the continuous laser and the pulse high-low level sequence formed by photoelectric conversion, high-speed recording of the number and state of ink droplet ejection is achieved. Through a standard comparison counter and multiple pulse count counters within the timing processing module, and with the aid of a simplified and efficient timing algorithm, accurate sorting and positioning of interrupted ink droplets are achieved. Through the unique coordinate information of pixels on the OLED pixel substrate, the sequence binding of defective pixels with interrupted ink droplets is realized. The compensation process for defective pixels is completed through the secondary moving module and the RGB compensation printhead. The main printing process and the defect detection and compensation process are performed simultaneously, greatly improving the efficiency of printed OLED manufacturing.

[0053] In some embodiments, if the standard comparison value and the count value are equal, i.e., CNT_0 = CNT_m, the repeated increment and comparison operations continue to be performed.

[0054] In some embodiments, the pixel pit coordinate information of each RGB pixel pit 100 on the OLED pixel substrate 11 has a unique standard comparison value (CNT_0) and a count value (CNT_Num m). The count value is divided by three and the remainder is taken. If the remainder is equal to 1, the defective pixel color is red (R); if the remainder is equal to 2, the defective pixel color is green (G); and if the remainder is equal to 0, the defective pixel color is blue (B).

[0055] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0056] (1) The continuous laser-based printed OLED defect detection and compensation system of the present invention is equipped with a main control module, a piezoelectric drive module, a main moving module, a secondary moving module, an RGB main piezoelectric nozzle, and an RGB compensation nozzle. The RGB main piezoelectric nozzle and the RGB compensation nozzle are arranged in an array. The main control module is used to control, receive feedback data in real time, and regulate the process with high automation, which solves the problem of complicated human intervention in the printing preparation process of the whole equipment, achieves the optimization effect of printed OLED pixels, has high stability for inkjet printing, and does not require additional process steps when preparing large-area pixels, and has good compatibility. At the same time, the piezoelectric control module drives the arrayed RGB main piezoelectric nozzle or RGB compensation nozzle to spray multiple ink streams onto the OLED pixel substrate, realizing rapid large-area printing and greatly improving production efficiency.

[0057] (2) In the embodiment of the present invention, the detection signal acquisition part of the defective pixel adopts a combination of laser emitter and photoelectric receiver. By using the ink droplet backlight blocking effect of continuous laser and the pulse high and low level sequence formed by photoelectric conversion, the problem of difficult quantity acquisition and status monitoring during ink droplet ejection is solved, and high-speed recording of ink droplet ejection quantity and ejection status is realized without the need for expensive visual observation system, which effectively reduces costs.

[0058] (3) The defect pixel detection signal processing part of the present invention adopts a timing processing module. Through the standard comparison counter and multiple pulse count counters inside the module, and further with the help of a simplified and efficient timing algorithm, the precise sorting and positioning of the broken ink droplets are realized. Through the unique coordinate information of each pixel on the OLED pixel substrate, the sequence binding of defect pixels and broken ink droplets is realized, eliminating the visual acquisition and detection steps commonly used in traditional printed OLED defect detection.

[0059] (4) The defect compensation part of the present invention is equipped with an independent sub-moving module and an RGB compensation nozzle, so that when printing large-size OLEDs, the defect pixel compensation process can be carried out synchronously with the main printing process without interfering with each other, achieving the purpose of printing and compensating at the same time, which greatly improves the process preparation efficiency.

[0060] Combination Figure 10 As shown, correspondingly, this embodiment of the invention provides a method for detecting and compensating defects in printed OLEDs based on continuous lasers, applied to the aforementioned system for detecting and compensating defects in printed OLEDs based on continuous lasers, comprising:

[0061] S101, the main control module controls the main moving module to drive the RGB main piezoelectric printhead to perform a single printing motion along the positive X-axis, and the piezoelectric control module outputs a laser amplitude modulation signal to drive the RGB monochrome nozzle of the RGB main piezoelectric printhead to eject ink droplets.

[0062] S102. During the ink droplet's descent, the laser beam emitted by the laser source is intermittently blocked. The photoelectric sensor converts the received intermittent laser beam into pulse high and low level signals and transmits these signals to the timing processing module. The standard comparator counter in the timing processing module continuously increments, with the increment frequency synchronized with the laser amplitude modulation signal. The m-th pulse count counter increments when it detects a rising edge. After each increment, the standard comparator counter compares the standard comparison value with the count value of the pulse count counter.

[0063] S103. When the standard comparison value and the count value are not equal, it is determined that there is an ink jet interruption. The pulse counter number of the current pulse quantity counter and the standard comparison value are recorded and stored in the register of the timing processing module, and the standard comparison value is assigned to the count value.

[0064] S104. The timing processing module continuously transmits the pulse counter sequence number and the standard comparison value in the register to the main control module. The main control module determines the position information of the defective pixel based on the numerical information of the pulse counter sequence number and the standard comparison value, and controls the secondary moving module to move the corresponding monochrome compensation printhead of the RGB compensation printhead above the defective pixel. The piezoelectric control module drives the monochrome compensation printhead to eject ink droplets into the defective pixel, thus completing the compensation process of the defective pixel.

[0065] In some embodiments, the method further includes the following steps:

[0066] When the standard comparison value and the count value are equal, the repeated increment and comparison operation continues.

[0067] If the standard comparison value and the count value are equal, i.e., CNT_0 = CNT_m, continue to perform repeated increment and comparison operations.

[0068] Furthermore, the pixel pit coordinate information of each RGB pixel pit on the OLED pixel substrate 11 has a unique standard comparison value (CNT_0) and count value (CNT_Num m). The count value is divided by three and the remainder is taken. If the remainder is equal to 1, the defective pixel color is red (R); if the remainder is equal to 2, the defective pixel color is green (G); and if the remainder is equal to 0, the defective pixel color is blue (B).

[0069] This invention provides a method for defect detection and compensation in printed OLEDs based on continuous laser technology. The method includes a main control module, a main moving module, a secondary moving module, a timing processing module, a piezoelectric control module, an ink supply module, an RGB main piezoelectric printhead, an RGB compensation printhead, a laser emitter, a photodetector, and an OLED pixel substrate. By utilizing the ink droplet backlight blocking effect of the continuous laser and the pulse high / low level sequence formed by photoelectric conversion, high-speed recording of the number and state of ink droplets ejected is achieved. Through a standard comparison counter and multiple pulse count counters within the timing processing module, and with the aid of a simplified and efficient timing algorithm, accurate sorting and positioning of interrupted ink droplets are achieved. By using the unique coordinate information of pixels on the OLED pixel substrate, the sequence binding of defective pixels with interrupted ink droplets is realized. The compensation process for defective pixels is completed through the secondary moving module and the RGB compensation printhead. The main printing process and the defect detection and compensation process are performed simultaneously, greatly improving the efficiency of printed OLED fabrication.

[0070] It should be understood that the various forms of processes shown above can be used to reorder, add, or delete steps. For example, the steps described in this invention disclosure can be executed in parallel, sequentially, or in different orders, as long as the desired result of the technical solution disclosed in this invention can be achieved, and this is not limited herein.

[0071] The specific embodiments described above do not constitute a limitation on the scope of protection of this invention. Those skilled in the art should understand that various modifications, combinations, sub-combinations, and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this invention should be included within the scope of protection of this invention.

Claims

1. A printed OLED defect detection and compensation system based on continuous laser, characterized in that, include: Main control module, main moving module, secondary moving module, timing processing module, piezoelectric control module, ink supply module, RGB main piezoelectric printhead, RGB compensation printhead, laser emitter, photoelectric receiver and OLED pixel substrate; The main control module is electrically connected to the main moving module, the secondary moving module, the timing processing module, the piezoelectric control module, and the ink supply module, respectively. The RGB main piezoelectric printhead, the laser emitter, and the photoelectric receiver are mounted on the main moving module. The main moving module moves synchronously in the Y-axis direction, the RGB main piezoelectric printhead performs reciprocating printing motion in the X-axis direction, and the RGB compensation printhead is mounted on the secondary moving module and moves freely in the XYZ three-axis directions. The ink supply module supplies ink to the RGB main piezoelectric printhead and the RGB compensation printhead. The piezoelectric control module drives the RGB main piezoelectric printhead and the RGB compensation printhead to eject ink droplets onto the OLED pixel substrate. Each pixel pit coordinate information on the OLED pixel substrate has a unique standard comparison value and a corresponding count value. The count value is divided by three and the remainder is taken. If the remainder is equal to 1, the defective pixel color is red (R); if the remainder is equal to 2, the defective pixel color is green (G); if the remainder is equal to 0, the defective pixel color is blue (B). The RGB main piezoelectric nozzle includes m RGB monochrome nozzles, the RGB compensation nozzle includes three monochrome compensation nozzles, the laser emitter includes m laser sources, each laser source is used to emit one laser beam, and the photoelectric receiver includes m photoelectric sensors, each photoelectric sensor is used to receive the laser beam emitted by the corresponding laser source. The spatial arrangement of the RGB monochrome nozzles, the laser sources, and the photoelectric sensors is corresponding. The timing processing module is electrically connected to the photoelectric receiver. The timing processing module includes one standard comparator counter and m pulse count counters. The pulse count counter number of each pulse count counter is bound to a corresponding RGB monochrome nozzle. Both the standard comparator counter and the pulse count counters perform an incrementing operation, where m is a positive integer greater than 0. The main control module controls the main moving module to drive the RGB main piezoelectric printhead to perform a single printing motion along the positive X-axis. The piezoelectric control module outputs a laser amplitude modulation signal to drive the RGB monochrome nozzles of the RGB main piezoelectric printhead to eject ink droplets. During the droplet fall, the laser light emitted by the laser source is intermittently blocked. The photoelectric sensor converts the received intermittent laser light into pulse high and low level signals and transmits the pulse high and low level signals to the timing processing module. The standard comparison counter in the timing processing module continuously performs an incrementing operation, and the incrementing frequency is synchronized with the laser amplitude modulation signal. The m-th pulse count counter increments when it detects the arrival of the rising edge. After each incrementing operation, the standard comparison value is compared with the pulse count. The counter value of the device is compared. When the standard comparison value and the count value are not equal, it is determined that there is an ink jet interruption. The pulse counter number of the current pulse count counter and the standard comparison value are recorded and stored in the register of the timing processing module. The standard comparison value is assigned to the count value. The timing processing module continuously transmits the pulse counter number and the standard comparison value in the register to the main control module. The main control module determines the position information of the defective pixel based on the numerical information of the pulse counter number and the standard comparison value. It controls the secondary moving module to move the corresponding monochrome compensation printhead of the RGB compensation printhead above the defective pixel. The piezoelectric control module drives the monochrome compensation printhead to eject ink droplets into the defective pixel, completing the defective pixel compensation process.

2. The printed OLED defect detection and compensation system based on continuous laser as described in claim 1, characterized in that, The photoelectric sensor outputs a low level when it detects laser light and a high level when there is no laser light.

3. A method for defect detection and compensation in printed OLEDs based on continuous laser, characterized in that, The system for detecting and compensating defects in printed OLEDs based on continuous lasers, as described in any one of claims 1 to 2, comprises: The main control module controls the main moving module to drive the RGB main piezoelectric printhead to perform a single printing motion along the positive X-axis. The piezoelectric control module outputs a laser amplitude modulation signal to drive the RGB monochrome nozzle of the RGB main piezoelectric printhead to eject ink droplets. During the ink droplet's descent, the laser beam emitted by the laser source is intermittently blocked. The photoelectric sensor converts the received intermittent laser beams into pulse high and low level signals and transmits these signals to the timing processing module. A standard comparator counter in the timing processing module continuously increments, with the increment frequency synchronized with the laser amplitude modulation signal. The m-th pulse count counter increments upon detecting a rising edge. After each increment, the standard comparator counter compares its value with the count value of the pulse count counter. When the standard comparison value and the count value are not equal, it is determined that there is an ink jet interruption. The pulse counter number of the current pulse quantity counter and the standard comparison value are recorded and stored in the register of the timing processing module, and the standard comparison value is assigned to the count value. The timing processing module continuously transmits the pulse counter sequence number and the standard comparison value in the register to the main control module. The main control module determines the position information of the defective pixel based on the numerical information of the pulse counter sequence number and the standard comparison value, and controls the secondary moving module to move the corresponding monochrome compensation printhead of the RGB compensation printhead above the defective pixel. The piezoelectric control module drives the monochrome compensation printhead to eject ink droplets into the defective pixel, thus completing the compensation process of the defective pixel.

4. The method for defect detection and compensation of printed OLEDs based on continuous laser according to claim 3, characterized in that, Also includes: When the standard comparison value and the count value are equal, the repeated increment and comparison operation continues.

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