Printing apparatus with a plurality of nozzle heads and method for aligning a plurality of nozzle tips

Abstract

The present disclosure relates to a printing apparatus with a plurality of nozzle heads and method for aligning a plurality of nozzle tips. The printing apparatus with a plurality of nozzle heads according to the present disclosure includes a first nozzle head having a first nozzle tip for discharging ink and a first moving part for moving the first nozzle tip, and disposed at one side of a working area on a substrate; a second nozzle head having a second nozzle tip for discharging ink and a second moving part for moving the second nozzle tip, and disposed at the other side of the working area on the substrate; and a first camera disposed above the substrate to observe the first nozzle tip and the second nozzle tip at the same time.

What is claimed is: 
     
         1 . A printing apparatus with a plurality of nozzle heads, the apparatus comprising:
 a first nozzle head having a first nozzle tip for discharging ink and a first moving part for moving the first nozzle tip, and disposed at one section of a working area on a substrate;   a second nozzle head having a second nozzle tip for discharging ink and a second moving part for moving the second nozzle tip, and disposed at the other section of the working area on the substrate; and   a first camera disposed above the substrate to observe both the first nozzle tip and the second nozzle tip.   
     
     
         2 . The printing apparatus with a plurality of nozzle heads, according to  claim 1 ,
 further comprising a second camera disposed to observe both the first nozzle tip and the second nozzle tip in an inclined direction.   
     
     
         3 . The printing apparatus with a plurality of nozzle heads, according to  claim 2 ,
 further comprising a controller that controls driving of the first moving part and the second moving part based on an image obtained in the first camera and the second camera, to control each position of the first nozzle tip and the second nozzle tip.   
     
     
         4 . The printing apparatus with a plurality of nozzle heads, according to  claim 1 ,
 wherein the first nozzle head and the second nozzle head each comprises a high voltage application part for applying a voltage to ink in order to discharge the ink in an electrohydrodynamic method.   
     
     
         5 . The printing apparatus with a plurality of nozzle heads, according to  claim 2 ,
 wherein the first nozzle head and the second nozzle head are disposed to be spaced apart in a first axis direction with respect to the working area, and the second camera is disposed to be spaced apart from the first camera in a second axis direction intersecting the first axis.   
     
     
         6 . The printing apparatus with a plurality of nozzle heads, according to  claim 5 ,
 wherein the first nozzle tip and the second nozzle tip are disposed to be inclined so as to have an inclination with respect to the first axis.   
     
     
         7 . The printing apparatus with a plurality of nozzle heads, according to  claim 5 ,
 wherein the second camera is disposed to be inclined so as to have an inclination with respect to the second axis.   
     
     
         8 . The printing apparatus with a plurality of nozzle heads, according to  claim 5 ,
 wherein the first moving part and the second moving part are configured to enable at least three axis movements.   
     
     
         9 . A method for aligning a plurality of nozzle tips, the method comprising:
 a first nozzle aligning step of setting a reference position of a first nozzle tip for discharging ink within a working area through an image of a first camera observing the working area above a substrate and a second camera observing the working area in an inclined direction;   a second nozzle aligning step of setting a reference position of a second nozzle tip for discharging ink within the working area through the image of the first camera and the second camera;   a step of detecting a position of a substrate based on the image of the second camera; and   a printing preparation step of positioning the first nozzle tip and the second nozzle tip to a printing position on the substrate.   
     
     
         10 . The method for aligning a plurality of nozzle tips, according to  claim 9 ,
 wherein the reference position is set by positioning a distal end of the first nozzle tip or a distal end of the second nozzle tip at a center of a Field of View (FOV) of the first camera, and then by positioning the distal end of the first nozzle tip or the distal end of the second nozzle tip at a center of a FOV of the second camera.   
     
     
         11 . The method for aligning a plurality of nozzle tips, according to  claim 9 ,
 wherein after the first nozzle aligning step and the second nozzle aligning step, a step of moving the first nozzle tip and the second nozzle tip to designated positions is performed, wherein each designated position is spaced apart by a certain distance from the reference position.   
     
     
         12 . The method for aligning a plurality of nozzle tips, according to  claim 11 ,
 wherein the designated positions are set such that the first nozzle tip and the second nozzle tip are spaced apart from each other in a horizontal direction with respect to the reference position so as to prevent interference of the first nozzle tip and the second nozzle tip.   
     
     
         13 . The method for aligning a plurality of nozzle tips, according to  claim 12 ,
 wherein a third axis direction position of the designated position may be set as a position spaced apart by a predesignated distance from a position of the substrate detected by autofocusing the substrate.   
     
     
         14 . The method for aligning a plurality of nozzle tips, according to  claim 13 ,
 wherein at the step of moving to the designated position, the third axis direction position of the first nozzle tip and the second nozzle tip are adjusted by a driving part that moves the first nozzle tip, the second nozzle tip, the first camera and the second camera at the same time.   
     
     
         15 . The method for aligning a plurality of nozzle tips, according to  claim 14 ,
 wherein at the printing preparation step, the third axis direction position of the first nozzle tip and the second nozzle tip are adjusted by the driving part that moves the first nozzle tip, the second nozzle tip, the first camera and the second camera at the same time.   
     
     
         16 . The method for aligning a plurality of nozzle tips, according to  claim 9 ,
 wherein the step of detecting the position of the substrate comprising:
 detecting a height of the substrate using an image of the nozzle tip included in the image obtained through the second camera and the mirroring image of the nozzle tip reflected on the substrate.