A method for identifying mobile phone backlight module from both sides

Abstract

The present invention belongs to the technical field of mobile phone backlight module identification, and provides a method for identifying the front and back of a mobile phone backlight module, wherein the front and back images of the mobile phone backlight module are identified by an identification mechanism; the positions of a glass cover plate and the mobile phone backlight module are aligned according to the front and back images of the mobile phone backlight module; a UVW platform is corrected according to the front and back images of the mobile phone backlight module, and the center point, coordinate parameters and initial rotation angle of the UVW platform are determined; the center point and coordinate parameters of the front and back images are calculated by the edge coordinates of the front and back images of the mobile phone backlight module; and the target rotation angle of the front and back images of the mobile phone backlight module is calculated with reference to the coordinate parameters of the corrected glass cover plate. The method for identifying the front and back of a mobile phone backlight module of the present invention not only saves a set of visual modules and a set of motion modules, but also keeps the spatial size of the device unchanged, and improves the bonding yield without increasing the cost.

Description

Technical Field

[0001] The invention relates to the technical field of mobile phone backlight module identification, and in particular to a method for identifying a mobile phone backlight module from both sides. Background Art

[0002] During the process of visually aligning and bonding the mobile phone backlight and glass, the mobile phone backlight module and the glass cover are automatically assembled on the platform fixture, wherein the assembly sequence is as follows: (1) the mobile phone backlight module is placed on the fixture and moved to the photo taking position; (2) the four cameras are each positioned at a right angle; (3) the glass cover is automatically torn off and moved to the photo taking position; (4) the two cameras are each positioned at a right angle; (5) the mobile phone backlight module and the glass cover are respectively positionally corrected; (6) the mobile phone backlight module and the glass cover are pressed together, and then the finished product is automatically taken out and placed on the conveyor belt.

[0003] When taking pictures of the backlight module, most existing automatic assembly machines only take pictures on the front or back side. If both sides need to be photographed to locate the characteristic area of ​​the mobile phone backlight module, a set of visual modules and a set of motion modules need to be added, which makes the device larger, and the structure and software become relatively complex, resulting in a lower bonding yield and higher costs. Summary of the invention

[0004] In view of the defects in the prior art, the present invention provides a method for identifying the front and back sides of a mobile phone backlight module, which not only saves a set of visual modules and a set of motion modules, but also keeps the spatial size of the device unchanged, thereby improving the bonding yield without increasing the cost.

[0005] In order to solve the above technical problems, the present invention provides the following technical solutions:

[0006] A method for identifying the front and back of a mobile phone backlight module, wherein an identification mechanism is used to identify the front and back images of the mobile phone backlight module, wherein the identification mechanism comprises:

[0007] A fixture, which is used to carry the mobile phone backlight module;

[0008] Four CCD cameras, which are respectively located directly above the four right angles of the mobile phone backlight module, and are used to capture images of the four right angles on the front of the mobile phone backlight module;

[0009] Four triangular prisms are respectively embedded at four right angles of the fixture to reflect images at four right angles on the back of the mobile phone backlight module;

[0010] A driving assembly, which is used to drive the two CCD cameras on the left side or the two CCD cameras on the right side to lift and translate respectively, so that the two CCD cameras on the left side receive the reflected light from the left triangular prism or the two CCD cameras on the right side receive the reflected light from the right triangular prism;

[0011] The positions of the glass cover plate and the mobile phone backlight module are aligned according to the front and back images of the mobile phone backlight module.

[0012] Furthermore, the alignment of the glass cover plate and the mobile phone backlight module according to the front and back images of the mobile phone backlight module includes:

[0013] Correct the UVW platform position according to the front and back images of the mobile phone backlight module to determine the center point, coordinate parameters and initial rotation angle of the UVW platform;

[0014] Calculate the center points and coordinate parameters of the front and back images through the edge coordinates of the front and back images of the mobile phone backlight module;

[0015] Using the coordinate parameters of the corrected glass cover as a reference, calculate the target rotation angle of the front and back images of the mobile phone backlight module;

[0016] Calculate the coordinate deviation between the mobile phone backlight module and the glass cover according to the coordinate parameters and initial rotation angle of the UVW platform, the coordinate parameters of the front and back images of the mobile phone backlight module, and the target rotation angle;

[0017] The UVW platform controls the movement of the mobile phone backlight module according to the position deviation, so that the position of the mobile phone backlight module and the glass cover are aligned.

[0018] Furthermore, the UVW platform position correction is performed according to the front and back images of the mobile phone backlight module to determine the center point, coordinate parameters and initial rotation angle of the UVW platform, including:

[0019] The CCD camera is corrected for distortion using a checkerboard calibration plate;

[0020] Sobel operator and Threshold operator are used to extract edge gradient information of mobile phone backlight module image, and contour gradient similarity is used to extract edge information;

[0021] The geometric edge algorithm is used to extract the intersection points of edge information and determine the center point, coordinate parameters and initial rotation angle of the UVW platform.

[0022] Furthermore, the jig is arranged on a workbench, a support plate is fixedly mounted on the workbench, and the driving assembly is fixedly mounted on the support plate.

[0023] Furthermore, the driving assembly includes a horizontal driving assembly, which is fixedly connected to the support plate, and the driving end of the horizontal driving assembly is fixedly installed with a first fixed plate, and lifting assemblies are symmetrically installed on both sides of the first fixed plate, and a second fixed plate is fixedly installed on the lifting assembly, and two CCD cameras are respectively installed at both ends of the second fixed plate, and the horizontal driving assembly and the two lifting assemblies are electrically connected to the PLC controller.

[0024] Furthermore, the horizontal drive assembly includes a servo motor and a screw rod, the servo motor and the screw rod are drive-connected, the servo motor and the screw rod are fixedly connected to the support plate, the nut seat of the screw rod is drive-connected to the first fixed plate, and the servo motor is electrically connected to the PLC controller.

[0025] Furthermore, the cross section of the triangular prism is a rectangle, the side surface of the triangular prism is an isosceles right triangle, the waist surface of the triangular prism is a square, and the waist surface of the triangular prism is coated with a black film.

[0026] From the above technical scheme, it can be seen that the beneficial effects of the present invention are as follows: first, the front and back images of the mobile phone backlight module are identified by the identification mechanism. During the identification process of the mobile phone backlight module, the mobile phone backlight module is placed on a jig, and a triangular prism is added to the four corners of the jig respectively. The four right angles of the mobile phone backlight module are respectively located in the areas of the four triangular prisms. The height and translation position of the four CCD cameras are adjusted by the driving mechanism, and the 180-degree reflection of the triangular prism is received to realize the front and back shooting of the mobile phone backlight module, which not only saves a set of visual modules and a set of motion modules, but also keeps the spatial size of the equipment unchanged; the positions of the glass cover plate and the mobile phone backlight module are aligned according to the front and back images of the mobile phone backlight module, so as to improve the bonding yield without increasing the cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following is a brief introduction to the drawings required for the specific embodiments or the description of the prior art. In all the drawings, similar elements or parts are generally identified by similar reference numerals. In the drawings, the elements or parts are not necessarily drawn according to the actual scale.

[0028] Figure 1 is a flow chart of the present invention;

[0029] Figure 2 This is a flow chart of the present invention for aligning the positions of the glass cover plate and the mobile phone backlight module according to the front and back images of the mobile phone backlight module;

[0030] Figure 3This is a flow chart of the present invention performing position correction on the UVW platform according to the front and back images of the mobile phone backlight module, and determining the center point, coordinate parameters and initial rotation angle of the UVW platform;

[0031] Figure 4 It is a structural schematic diagram of the present invention;

[0032] Figure 5 It is a schematic diagram of the structure of the prism of the present invention;

[0033] Figure 6 This is the optical path diagram of the present invention.

[0034] Reference numerals:

[0035] 1- working table; 2- supporting plate;

[0036] 11- fixture; 12- mobile phone backlight module; 13- triangular prism; 21- servo motor; 22- screw rod; 23- first fixing plate; 24- lifting assembly; 25- second fixing plate; 26- CCD camera;

[0037] 131- cross section; 132- waist section; 133- side section. DETAILED DESCRIPTION

[0038] The following embodiments of the technical solution of the present invention are described in detail in conjunction with the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present invention, and are therefore only used as examples, and cannot be used to limit the protection scope of the present invention.

[0039] See also Figure 1-Figure 3 As shown, this embodiment provides a method for identifying the front and back sides of a mobile phone backlight module 12, which identifies the front and back images of the mobile phone backlight module 12 through an identification mechanism, and the identification mechanism includes a fixture 11, four CCD cameras 26, four triangular prisms 13 and a driving component.

[0040] The fixture 11 is used to carry the mobile phone backlight module 12 .

[0041] The four CCD cameras 26 are respectively located directly above the four right angles of the mobile phone backlight module 12 , and are used to capture images of the four right angles on the front side of the mobile phone backlight module 12 .

[0042] Four triangular prisms 13 are respectively embedded at four right angles of the fixture 11 for reflecting images from four right angles on the back side of the mobile phone backlight module 12 . The upper surfaces of the four triangular prisms 13 are flush with the upper surface of the fixture 11 .

[0043] The driving component is used to drive the two CCD cameras 26 on the left or the two CCD cameras 26 on the right to lift and translate respectively, so that the two CCD cameras 26 on the left receive the reflected light from the left triangular prism 13 or the two CCD cameras 26 on the right receive the reflected light from the right triangular prism 13, so as to realize the front and back shooting of the mobile phone backlight module 12, which not only saves a set of visual modules and a set of motion modules, but also keeps the spatial size of the device unchanged.

[0044] The positions of the glass cover plate and the mobile phone backlight module 12 are aligned according to the front and back images of the mobile phone backlight module 12, thereby improving the bonding yield without increasing the cost.

[0045] In this embodiment, the position alignment of the glass cover plate and the mobile phone backlight module 12 according to the front and back images of the mobile phone backlight module 12 includes:

[0046] The UVW platform position is corrected according to the front and back images of the mobile phone backlight module 12 to determine the center point and coordinate parameters (θ Y1 ,θ Y2 ,θ X ) and the initial rotation angle θ0.

[0047] The center point and coordinate parameters (δ Y1 , δ Y2 , δ X ).

[0048] The target rotation angle δ of the front and back images of the mobile phone backlight module 12 is calculated by taking the coordinate parameters of the glass cover after correction as a reference. θ .

[0049] According to the coordinate parameters and initial rotation angle of the UVW platform, the coordinate parameters of the front and back images of the mobile phone backlight module 12, and the target rotation angle, the coordinate deviation (δ v , δ w , δ u ), where δ v =Rcos(δ θ +δ Y1 +θ0)-Rcos(θ Y1 +θ0),δ w =Rcos(δ θ +δ Y2 +θ0)-Rcos(θ Y2 +θ0),δ u =Rcos(δ θ +δ X +θ0)-Rcos(θ X+θ0), R is the rotation radius.

[0050] The UVW platform controls the movement of the mobile phone backlight module 12 according to the position deviation, so that the positions of the mobile phone backlight module 12 and the glass cover plate are aligned, thereby improving the alignment accuracy of the mobile phone backlight module 12 and the glass cover plate.

[0051] In this embodiment, the UVW platform position correction is performed according to the front and back images of the mobile phone backlight module 12 to determine the center point, coordinate parameters and initial rotation angle of the UVW platform, including:

[0052] The CCD camera 26 is subjected to distortion correction using a checkerboard calibration plate.

[0053] The Sobel operator and Threshold operator are used to extract the edge gradient information of the mobile phone backlight module 12 image, and the edge information is extracted using the contour gradient similarity.

[0054] The geometric edge algorithm is used to extract the intersection point of the edge information and determine the center point of the UVW platform, (θ Y1 ,θ Y2 ,θ X ) and the initial rotation angle θ0.

[0055] In this embodiment, the fixture 11 is disposed on a workbench 1 , a support plate 2 is fixedly mounted on the workbench 1 , and a driving assembly is fixedly mounted on the support plate 2 .

[0056] See also Figure 4-Figure 5 As shown, the driving assembly includes a horizontal driving assembly, which is fixedly connected to the support plate 2, and a first fixed plate 23 is fixedly installed on the driving end of the horizontal driving assembly. Lifting assemblies 24 are symmetrically installed on both sides of the first fixed plate 23, and a second fixed plate 25 is fixedly installed on the lifting assembly 24. Two CCD cameras 26 are respectively installed at both ends of the second fixed plate 25, and the horizontal driving assembly and the two lifting assemblies 24 are electrically connected to the PLC controller.

[0057] In actual use, the horizontal driving assembly is controlled by the PLC controller to drive the four CCD cameras 26 to move horizontally, so that the four CCD cameras 26 are respectively located directly above the four prisms, so as to realize the shooting of the front of the mobile phone backlight module 12; with the center position of the fixture 11 as a reference, the horizontal driving assembly is controlled by the PLC controller to drive the four CCD cameras 26 to move to the right side of the fixture 11, and at the same time, the two CCD cameras 26 on the left are located on the right side of the two triangular prisms 13 on the left, and the lifting assembly 24 on the left is controlled by the PLC controller to extend, so as to drive the two CCD cameras 26 on the left to descend, so as to receive the light signal after two total reflections of the triangular prism 13, and take pictures of the reverse side of the two right angles on the left side of the mobile phone backlight module 12. On the contrary, the horizontal driving component is controlled by the PLC controller to drive the four CCD cameras 26 to move to the left side of the fixture 11. At the same time, the two CCD cameras 26 on the right are located on the left side of the two triangular prisms 13 on the right, and the lifting component 24 on the right is extended by the PLC controller to drive the two CCD cameras 26 on the right to descend, so as to receive the light signal after two total reflections of the triangular prism 13, take pictures of the back side of the two right angles on the right side of the mobile phone backlight module 12, and realize the shooting of the back side of the mobile phone backlight module 12; the horizontal movement distance of the horizontal driving component and the extension or shortening distance of the lifting component 24 are calculated according to the size of the triangular prism 13 and the size of the mobile phone backlight module 12; the lifting component 24 uses an electric telescopic rod or an electric cylinder.

[0058] In this embodiment, the horizontal drive assembly includes a servo motor 21 and a screw rod 22, the servo motor 21 and the screw rod 22 are drive-connected, the servo motor 21 and the screw rod 22 are fixedly connected to the support plate 2, the nut seat of the screw rod 22 is drive-connected to the first fixed plate 23, and the servo motor 21 is electrically connected to the PLC controller.

[0059] In actual use, the PLC controller controls the rotation of the servo motor 21 to drive the nut seat of the screw rod 22 to move horizontally, thereby controlling the horizontal movement of the first fixing plate 23 and driving the movement of the CCD camera 26 .

[0060] In this embodiment, the cut surface 131 of the triangular prism 13 is a rectangle, the side surface 133 of the triangular prism 13 is an isosceles right triangle, the waist surface 132 of the triangular prism 13 is a square, and the waist surface 132 of the triangular prism 13 is coated with a black film to improve the total reflection effect of the waist surface 132. The light path diagram of the two right-angle reflections of the left side of the mobile phone backlight module 12 by the triangular prism is shown in FIG. Figure 6As shown, the rectangular image A on the left side of the mobile phone backlight module 12 is incident on the left side of the prism and projected into image A1, and is projected into image A2 after a first reflection from the waist surface 132 on the left side of the triangular prism 13, and then is projected into image A3 after a second reflection from the waist surface 132 on the right side of the triangular prism 13, and finally, is incident on the CCD chip of the CCD camera 26.

[0061] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein by equivalents. These modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present invention, and they should all be included in the scope of the claims and specification of the present invention.

Claims

1. A method for identifying the front and back of a mobile phone backlight module, wherein the front and back images of the mobile phone backlight module (12) are identified by an identification mechanism, characterized in that: The identification mechanism comprises: A fixture (11) used to support a mobile phone backlight module (12); Four CCD cameras (26), which are respectively located directly above the four right angles of the mobile phone backlight module (12) and are used to capture images of the four right angles on the front of the mobile phone backlight module (12); Four triangular prisms (13) are respectively embedded at four right angles of the fixture (11) and are used to reflect images at four right angles on the back side of the mobile phone backlight module (12); A driving assembly, used for driving the two CCD cameras (26) on the left side or the two CCD cameras (26) on the right side to lift and translate respectively, so that the two CCD cameras (26) on the left side receive reflected light from the left triangular prism (13) or the two CCD cameras (26) on the right side receive reflected light from the right triangular prism (13); Aligning the positions of the glass cover plate and the mobile phone backlight module (12) according to the front and back images of the mobile phone backlight module (12); The method of aligning the positions of the glass cover plate and the mobile phone backlight module (12) according to the front and back images of the mobile phone backlight module (12) comprises: The UVW platform position is corrected according to the front and back images of the mobile phone backlight module (12) to determine the center point and coordinate parameters (θ Y1 ,θ Y2 ,θ X ) and the initial rotation angle θ0; The center points and coordinate parameters of the front and back images are calculated using the edge coordinates of the front and back images of the mobile phone backlight module (12) , , ); Using the coordinate parameters of the corrected rear glass cover as a reference, calculate the target rotation angle of the front and back images of the mobile phone backlight module (12) ; The coordinate deviation between the mobile phone backlight module (12) and the glass cover is calculated based on the coordinate parameters and initial rotation angle of the UVW platform, the coordinate parameters of the front and back images of the mobile phone backlight module (12), and the target rotation angle. , , ),in, , , , R is the radius of rotation; The UVW platform controls the movement of the mobile phone backlight module (12) according to the position deviation, so that the positions of the mobile phone backlight module (12) and the glass cover plate are aligned; The UVW platform position correction is performed according to the front and back images of the mobile phone backlight module (12) to determine the center point, coordinate parameters and initial rotation angle of the UVW platform, including: A checkerboard calibration plate is used to correct the distortion of the CCD camera (26); The Sobel operator and the Threshold operator are used to extract the edge gradient information of the mobile phone backlight module (12) image, and the edge information is extracted using the contour gradient similarity; The geometric edge algorithm is used to extract the intersection points of edge information, and the center point, coordinate parameters and initial rotation angle of the UVW platform are determined; The jig (11) is arranged on a workbench (1), a support plate (2) is fixedly mounted on the workbench (1), and a drive assembly is fixedly mounted on the support plate (2); The driving assembly comprises a horizontal driving assembly, the horizontal driving assembly is fixedly connected to the support plate (2), a first fixed plate (23) is fixedly mounted on the driving end of the horizontal driving assembly, lifting assemblies (24) are symmetrically mounted on both sides of the first fixed plate (23), a second fixed plate (25) is fixedly mounted on the lifting assembly (24), two CCD cameras (26) are respectively mounted on both ends of the second fixed plate (25), and the horizontal driving assembly and the two lifting assemblies (24) are electrically connected to a PLC controller; The horizontal drive assembly comprises a servo motor (21) and a screw rod (22); the servo motor (21) and the screw rod (22) are drivingly connected; the servo motor (21) and the screw rod (22) are fixedly connected to the support plate (2); a nut seat of the screw rod (22) is drivingly connected to a first fixed plate (23); and the servo motor (21) is electrically connected to a PLC controller.

2. A method for identifying the front and back sides of a mobile phone backlight module according to claim 1, characterized in that: The cut surface (131) of the triangular prism (13) is a rectangle, the side surface (133) of the triangular prism (13) is an isosceles right triangle, the waist surface (132) of the triangular prism (13) is a square, and the waist surface (132) of the triangular prism (13) is coated with a black film.

Images