Patent Publication Number: US-2022231264-A1

Title: Process for producing flexible oled screens

Description:
RELATED APPLICATIONS 
     This application claims priority to U.S. Provisional Patent Application Ser. No. 62/870,839 filed on Jul. 5, 2019 and to U.S. Provisional Patent Application Ser. No. 62/908,133 filed on Sep. 30, 2019. 
    
    
     FIELD OF THE INVENTION 
     This invention relates generally to processes for producing flexible organic light emitting diode (“OLED”) screens, and more to processes for producing such screens for an aircraft from standards sized OLED screens. 
     BACKGROUND OF THE INVENTION 
     Today&#39;s flexible OLED market is primarily focused on smartphones, notebooks, monitors, and home displays. Applicant has previously identified the desirability and applicability of incorporating these screens into aircraft. See, International Application No. PCT/EP2019/063848 filed on May 28, 2019 the entirety of which is incorporated herein by reference. Specifically, it has been found that it would be beneficial to incorporate the flexible OLED screens in, for example, a lining panel, a ceiling panel, a floor panel, a hat rack, a cabin door, a compartment separation module, a window blind, a luggage compartment door, a galley sidewall, and a lavatory monument sidewall, to name a few. 
     However, as noted above, the current OLED market is focused primarily towards high volume consumer goods like smartphones, notebooks, monitors, home displays, and the like. Accordingly, due to the high costs associated with setting up manufacturing lines for OLED screens, the flexible OLED screens currently being produced are sized for these consumer products and mostly have a rectangular shape. While these sizes and shapes are acceptable for the various listed consumer goods, it is believed that the sizes and shapes of these screens are not optimally suitable for use in aircraft environments. 
     For example, while it is known to arrange two or more screens into an array to provide a display surface with an increased surface size compared to just one screen, the current OLED screens have bezels that are too large for use in an aircraft environment when arranged in a multiple panel array. More specifically, the currently produced OLED screens have bezels that are in the range of four to seven mm. Thus, the crosses or bands formed by adjacent bezels are too wide when the screens are placed adjacent to one another. 
     The main function of the bezels is to cover the electronic circuits controlling the pixels of the OLED screen. The bezels also function to protect the OLED display from the penetration of moisture and oxygen (that will damage the organic content in the materials forming the OLED screen). 
     Moreover, even though these OLED screens are being produced for the consumer products, due to the nature of the production processes, it is not a simple task to use existing production lines to produce differently sized screens. Thus, while there is some demand for the OLED screens with the appropriate size and shape for an aircraft environment, the demand does not out weight the high cost of establishing or setting up a new production line for appropriately sized and shaped OLED screens for aircraft. According to current estimates, the cost of setting up one production line for an OLED screen with one specific size is believed to be about $20 million. Thus, due to the different sizes and shapes needed and the relatively low production output expected, it is not currently economically feasible to merely set up new production lines to make the OLED screens for an aircraft environment. 
     Accordingly, it would be desirable to have effective and efficient processes for the production of OLED screens that are sized and shaped for use in an aircraft environment. 
     SUMMARY OF THE INVENTION 
     The present invention is directed at solving one or more of these problems by providing a process for reducing the size of production, or standard sized, OLED screens. More specifically, in one or more aspects, the present invention provides processes that reduce the size of the OLED screens, providing the OLED screen with a configuration that is more suitable to be utilized in an array configuration. According to the various processes, to ensure the resizing of the size and shape of the production OLED screens occurs without moisture and oxygen penetrating into the display, a combination of laser cutting/welding and atmospheric plasma polymer coating processes are used. Thus, the present processes provide for the cost-effective production of OLED screens with customized/specified size and shape from production OLED screens. 
     Therefore, in one aspect the present invention may be characterized broadly as providing a process for producing flexible OLED screens by: obtaining an OLED screen from a production line; cutting the OLED screen with a laser to reduce the size of the OLED screen and provide a cut OLED screen comprising a cut edge; and, coating the cut edge by a plasma coating process to provide the cut OLED screen with a reduced size compared to the OLED screen from the production line. 
     The plasma coating process may occur at atmospheric pressure. 
     The plasma coating process may include applying an organic polymer at the cut edge. The plasma coating process may include applying a silicon oxide coating at the cut edge. 
     Cutting the OLED screen may include reducing a size of a display area of the OLED screen. The process may also include redefining the display area of the OLED screen based on the reduced size of the display area. The display area of the OLED screen after the size has been cut may be a rectangular shape. The display area of the OLED screen after the size has been cut may include a shape with a perimeter having a non-linear edge. 
     The process may include arranging two OLED screens with a reduced size in an array. 
     In another aspect of the present invention, the present invention may be generally characterized as an OLED screen produced according to the processes disclosed herein. 
     In a further aspect of the present invention, the present invention may be generally characterized as an OLED screen produced according to the processes disclosed herein. 
     In still another aspect of the present invention, the present invention may be characterized as providing a display surface having at least two OLED screens produced according to present processes and in which the at least two OLED screens are positioned adjacently to one another so as to form an array. 
     In yet a further aspect of the present invention, the present invention may be generally characterized as an aircraft having the display surface described herein. 
     These aspects, described in more detail below and in the attached drawings, are believed to provide advantages over the current state of the art, allowing for the effective and efficient production of OLED screens for an aircraft environment. These and other benefits will be appreciated by those of skill in art in view of the present disclosure. 
    
    
     
       DETAILED DESCRIPTION OF THE DRAWINGS 
       One or more exemplary embodiments of the present invention will be described below in conjunction with the following drawing figure, in which: 
         FIG. 1  shows a flow chart for one or more processes according to one or more aspects of the present invention; 
         FIG. 2  shows an exemplary production OLED screen and three resized/reshaped OLED screens produced from the production OLED screen according to one or more aspects of the present invention; 
         FIG. 3A  depicts a front view of an OLED display screen that may be used according to one or more aspects of the present invention; 
         FIG. 3B  depicts a side, cutaway view of the OLED display screen shown in  FIG. 3A ; 
         FIG. 4  shows an array with multiple OLED screens produced according to one or more aspects of the present invention; and, 
         FIG. 5  shows an airplane with multiple OLED screens therein. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     As noted above, the present invention provides OLED screens that are more readily adapted to use in an aircraft environment compared with production OLED screens that are designed for consumer goods. The processes of the present invention resize and/or reshape the OLED screens produced for the consumer goods so that the OLED screens have a size and shape that it more suitable for the aircraft environment. Additionally, the processes may be used to change the size and shape of the production OLED screens by cutting through a portion of the display area of the production OLED screens. This provides the ability to make custom sizes and shapes to fit within the aircraft environment. 
     With these above general aspects of the present invention in mind, one or more embodiments of the present invention will be described with the understanding that the following description is not intended to be limiting. 
     An exemplary process  100  according to the present invention is shown in  FIG. 1 . and will be discussed below. It should be understood and appreciated that while the exemplary process  100  is discussed in terms of OLED screen production for the aircraft environment, it should be appreciated that the resized and/or reshaped OLED screens could be used in any environment. 
     As shown in  FIG. 1 , in first step  102 , an OLED screen  200  (see,  FIG. 2 ) from a production line (or a production OLED screen) is obtained. By “a production OLED screen,” it is meant that the obtained OLED screen  200  has all the materials and layers of material as well as electronics so as to function, when installed in an electronic device. While it may require further production steps to install such a screen in the final electronic device, the production of the screen itself is essentially complete. 
     As shown in  FIGS. 3A and 3B , an OLED screen  300  is depicted in which control circuitry  306  has been moved to behind the display area  302 , providing the OLED screen  300  with a bezel area  304  that is reduced or eliminated compared with current OLED display screens. 
     Specifically, the OLED screen  300  depicted in  FIGS. 3A and 3B  includes a lower substrate layer  308 , the control circuitry  306  disposed on the substrate layer  308 , a thin film transistors layer  310  disposed on the control circuitry  306 , an OLED layer  312  above the thin film transistors layer  310 , and an encapsulation layer  314  on top of the OLED layer  312 . The use of “above,” “on top” and other similar language is meant in relation to the orientation shown in the drawing. Thus, on one side of the thin film transistors layer  310  is the OLED layer  312 , while on the opposite side of the thin film transistors layer  310  is the control circuitry or circuit layer  306 . Accordingly, in the OLED screen  300  depicted in  FIGS. 3A and 3B , rather than connecting the pixel driving circuits  306  to the transistors layer  310  in a horizontal plane (as in conventional OLED screens), the connection between the two is in a vertical plane. 
     In order to manufacture the OLED display screen  300  depicted in  FIGS. 3A and 3B , the circuit layer  306  may be the first layer to be deposited on the substrate  308 . Above the circuit layer  306 , the thin film transistors layer (“TFT” layer)  310  may be deposited with their already existing fine-masks. The TFT layer  310  will also include spaces on these fine-masks so the conductive molecules can be deposited layer by layer, to form the vertical connections needed. Alternatively, a different manufacturing approach could be to leave holes in every TFT layer and deposit the conductive molecules within the holes once the latest TFT layer has been deposited. Once the TFT layer  310  has been deposited, the OLED layer  312  and encapsulation layers  314  can be applied to form the OLED display screen  300 . Accordingly, the OLED display screen  300  depicted in  FIGS. 3A and 3B  may be used as the production OLED screen  200  in  FIG. 2 . 
     Returning to  FIG. 2 , once the production OLED screen  200  from the production line has been obtained, the process proceeds to cutting  102  where the OLED screen  200  is cut with a laser. For example, an automatic device carrying a microsecond or femtosecond laser will cut through the layers of the production OLED screen with a pulsing laser to obtain a desired size/shape. As an example, the automatic device may be a robot arm controlled by a computer or other processor configured to execute a set of computer instructions. As the robot arm moves, the laser is discharged with a width and pulse that is determined based, in part, on the materials and thickness of the production OLED screen  200 . 
     The use of a laser to cut the screen is important because while cutting  102 , a wall effect will be induced around the OLED layer, in response to the heat transfer from the laser beam. The wall effect will be mechanical, chemical, or both. A mechanical wall effect would be the melting of one of the plastic layers of the OLED screen  200 , whereas a chemical wall effect would be produced by a chemical reaction of the existing OLED screen  200  molecules and the surrounding oxygen and water moisture, induced as well by the heat transfer from the laser beam. Accordingly, as a result of the wall effect, the organic materials of the production OLED screen  200  will not be exposed to moisture or oxygen. It is also contemplated that other heat transfer cutting methods could be used, such as, for example, plasma cutting. 
     As shown in  FIG. 2 , once the cutting  102  is performed and completed, the production OLED screen  200  will have a cut edge  202 . Returning to  FIG. 1 , the process  100  may then proceed to a coating step  104 , preferably a plasma polymer coating, and most preferably an atmospheric plasma polymer coating. 
     As is known, in atmospheric plasma polymer coating, solid polymers are converted into plasma polymers with an electrical field. The plasma polymers are ejected through a fine nozzle to the cut area, so they can be deposited at molecular level. The length of these polymers is typically 2 to 3 atoms, so the adherence and the packaging is superior compared to other coatings and processes which utilize or rely on long-chain polymers. Since atmospheric plasma polymer coating is performed at atmospheric pressure, it does not require expensive vacuum environments to be developed. Thus, it is believed to be particularly beneficial in the present processes. The temperature of the plasma projection should not reach a temperature where the display can be damaged. Some conventional atmospheric plasma polymer coating devices have an operation temperature in the range of 50° C.-130° C., which is believed to be suitable for use with the OLED screens  200 . 
     It is contemplated that at least two types of materials can be used for the atmospheric plasma polymer coating: silicon oxides (SiO x ) and organic (methane, ethane, e.g.) gases. Silicon oxides have better coating properties but tend to be more rigid, while the organic polymers do not have as high coating properties, but they provide more acceptable flexibility ratios. A combination of these materials may also be utilized. 
     The coating  104  is performed on the cut edges  202  to seal and prevent future moisture or oxygen penetration. Accordingly, it can also be performed by a device that follows the path of the laser in the cutting  102 . 
     As shown in  FIG. 2 , such an OLED screen  200   a  is shown on the top right. It is also contemplated in some aspects that the cutting  102  will create cut edges  202  inside of a display area  206  of the production OLED screen  200 . As will be appreciated, in some aspects, the bezels  204 , the display area  206  or both will be cut in the cutting  102  step. 
     Accordingly, in the middle right of  FIG. 2 , an OLED screen  200   b  is shown with a reduced size display screen  206   a  that has an edge  202  that is straight and that was cut through the display area  206  of the production OLED screen  200 . In the bottom right of  FIG. 2 , an OLED screen  200   c  is shown with a reduced size display screen  206   a  that has an edge  202  that is curved, or non-linear, and that was cut through the display area  206  of the production OLED screen  200 . Other shapes may be formed. 
     For screens  200   b ,  200   c , in which a cut has been made through the display area  206  of the production OLED screen  200 , as shown in  FIG. 1 , the process  100  includes a step of redefining the display size  108 . In the step of redefining the display size  108 , it is contemplated that the latest functional pixel per row and column is determined. Using a computer, the pixels that have become in-operative due to the cutting  102  can be determined and used to determine a new display size  206   a  that is smaller in at least one directional measurement (height, width, or both) compared to the display area  206  of the production OLED screen  200 . This will result in a new, smaller resolution. Preferably, it is confirmed or verified that the in-operative pixels are outside of the expected resolution. Once the in-operative pixels are determined, and the new resolution defined, any operative pixels that lie outside the display size  206   a  are deactivated. 
     More specifically, while the cutting  102  should be performed in a way that ensures that the damaged pixels do not extend beyond a certain row and certain column of the display area  206   a , due to the thermal effect of the laser (or other cutting method), it is contemplated that some pixels inside of the remaining display area  206   a  will be damaged. For example, there may be some rows and/or columns proximate the cut edge that include some pixels that work and some pixels that do not work. Once the maximum row and/or column is determined, any functional pixels outside of these limits should be deactivated. 
     In some embodiments, the resized/reshaped OLED screens  200   a ,  200   b ,  200   c  produced according to the present processes may be placed adjacent to another resized/reshaped OLED screens  200   a ,  200   b ,  200   c  produced according to the present process or next to a production OLED screen  200  so as to form an array  400 , as shown in  FIG. 4 . In the array  400 , the space taken up by the bezels  204  (see  FIG. 2 ) within the combined display area is acceptable for the array  400 . 
     Whether arranged in an array  400 , or used alone, the present processes are believed to provide for the ability to effectively and efficiently produce custom sizes and shapes for OLED screens from production OLED screens  200 , which, for example, can be used within an aircraft environment. For example, as shown in  FIG. 5 , an aircraft  500  includes two OLED screens  502 . The OLED screens  502  may be individual the OLED screens  200   a ,  200   b ,  200   c  ( FIG. 2 ), or the array  400  ( FIG. 4 ). 
     While at least one exemplary embodiment of the present invention(s) is disclosed herein, it should be understood that modifications, substitutions and alternatives may be apparent to one of ordinary skill in the art and can be made without departing from the scope of this disclosure. This disclosure is intended to cover any adaptations or variations of the exemplary embodiment(s). In addition, in this disclosure, the terms “comprise” or “comprising” do not exclude other elements or steps, the terms “a” or “one” do not exclude a plural number, and the term “or” means either or both. Furthermore, characteristics or steps which have been described may also be used in combination with other characteristics or steps and in any order unless the disclosure or context suggests otherwise. This disclosure hereby incorporates by reference the complete disclosure of any patent or application from which it claims benefit or priority.