Large-size 3D plate thickness full-scanning detection method

Abstract

The invention discloses a large-size 3D plate thickness full-scanning detection method, which relates to the technical field of plate thickness detection, and comprises the following steps: 1, carrying out vertical measurement by using one or more groups of line lasers to obtain output distances L, L1 and L2, controlling laser beams to move in a Z direction, and calculating the plate thickness size through a formula; 2, driving a laser head to carry out linear scanning through an X axis, obtaining real-time measurement data, transmitting a measurement signal to a controller, carrying out data conversion, and sending the data to an industrial computer; 3, the Y-axis server is responsible for positioning, processing position signals and sending the position signals to the industrial computer; 4, special algorithm software in the industrial computer receives data from the controller and the server, and summarizes and processes the collected data to obtain thickness information of each matrix with the minimum size of 0.005 * 0.005 mm; and 5, outputting the thickness data of the whole board to a client according to a 3D positioning algorithm.

Description

Technical Field

[0001] The present invention relates to the technical field of plate thickness detection, and in particular to a large-size 3D plate thickness full-scan detection method. Background Art

[0002] With the ultra-fast and ultra-integrated development of network speeds, the transmission demand for circuit boards has also increased exponentially, but the number of layers of circuit boards has reached its limit. It is difficult for the signals that the lines can transmit to break through. There is still space between the layers of the circuit boards that can be used, but it is limited by the device holes and communication holes. If you want to increase the number of lines, you must reduce the area occupied by the device holes and communication holes. Using the existing punching technology, it is difficult to accurately punch holes to the desired number of layers. If the holes are punched through, it is impossible to increase the number of lines.

[0003] Only by accurately drilling holes in required locations and preventing holes from being drilled in unnecessary places can the board surface utilization be improved and the line layout be increased. If the hole depth is fully controlled, the line layout can be improved by 30%.

[0004] However, the thickness deviation of the circuit board is difficult to measure. If the board thickness is measured locally, the board thickness a few millimeters away can exceed the board thickness. The existing 3D scanning technology is only for small objects and cannot detect products larger than 400 mm. If they are detected separately, the accuracy and efficiency cannot achieve the desired effect, especially in the production line. In view of this, a large-size 3D board thickness full scanning detection method is explored and studied. Summary of the invention

[0005] The present invention proposes a large-size 3D plate thickness full-scan detection method to solve the technical problems existing in the background technology.

[0006] To solve the above problems, the technical solution of the present invention is:

[0007] A large-size 3D plate thickness full-scan detection method comprises the following steps:

[0008] Step 1: Use one or more sets of line lasers to measure up and down, obtain the output spacing L, L1, L2, and control the laser beam to move in the Z direction, and calculate the plate thickness by the formula;

[0009] Step 2: Drive the laser head to perform linear scanning through the X-axis to obtain real-time measurement data, transmit the measurement signal to the controller, convert the data, and send it to the industrial computer;

[0010] Step 3: The Y-axis servo is responsible for positioning, processing the position signal and sending it to the industrial computer;

[0011] Step 4: The dedicated algorithm software in the industrial computer receives the data from the controller and the server, summarizes and processes the collected data, and obtains the thickness information of each matrix with a minimum of 0.005*0.005 mm;

[0012] Step 5: Based on the 3D positioning algorithm, output the thickness data of the entire plate to the client.

[0013] Preferably, in step one, one or more groups of line lasers include two laser transmitters and two receivers, one laser transmitter and receiver are located above the board surface, and the other laser transmitter and receiver are located below the board surface.

[0014] Preferably, in step one, the laser measurement adopts the triangulation principle, and the specific measurement steps are: the laser beam is emitted from the upper transmitter to the surface of the plate, and returns to the upper receiver after reflection. At the same time, the laser beam is emitted from the lower transmitter to the surface of the plate, and returns to the lower receiver after reflection. By measuring the transmission time and incident angle of the laser beam from the transmitter to the receiver, the distance of the reflection point of the laser beam on the surface of the plate is calculated, and the distance of the reflection point of the upper laser beam minus the distance of the reflection point of the lower laser beam is calculated, that is, the plate thickness.

[0015] Preferably, in step 1, the plate thickness calculation formula is: H = L-L1-L2;

[0016] Where H is the plate thickness; L is the laser measurement distance, that is, the distance from the laser beam from the upper transmitter to the lower receiver; L1 is the distance from the laser beam from the upper transmitter to the plate surface; L2 is the distance from the laser beam from the lower transmitter to the plate surface.

[0017] Preferably, in step 2, the movement range of the X-axis covers the entire width of the plate, and when the laser beam moves on the plate, the process of measuring L, L1, and L2 is repeated continuously.

[0018] Preferably, in step 2, the real-time measurement data is a series of timestamps and distance values ​​in millimeters, and the data is transmitted to an industrial computer via a wired or wireless connection.

[0019] Preferably, in step three, the Y-axis servo adopts a closed-loop control system, and drives the motor to move by comparing the deviation between the target position and the actual position to achieve precise positioning.

[0020] Preferably, in step 4, the plate is divided into a grid, the size of each grid unit is 0.005*0.005 mm, and the thickness of each grid unit is calculated, that is, the thickness information of each matrix with a minimum size of 0.005*0.005 mm is obtained.

[0021] Preferably, in step 4, the dedicated algorithm software uses a linear regression algorithm to convert the laser measurement data into thickness data.

[0022] Preferably, in step five, the 3D positioning algorithm uses a spatial interpolation technique to generate a 3D thickness model of the entire panel according to the thickness information of each grid unit.

[0023] The above technical solution of the present invention has the following beneficial technical effects:

[0024] 1. The present invention uses one or more groups of line lasers to measure up and down to measure the distance of any point on the surface of the plate, which enables the method to perform a comprehensive 3D scan of the entire plate, and drives a single group of lasers to move and scan a designated area through the XY axis to perform plate thickness accuracy detection. A high-precision motion control system is used to move the laser beam and the plate, which ensures that the laser beam can be accurately focused on any point on the surface of the plate, so that the technicians can accurately understand the thickness of the plate, and optimize the circuit layout and improve the utilization rate of the plate surface accordingly, so that the method can be applied in the field of high-precision dimensional detection, such as precision detection of precision device processing;

[0025] 2. The present invention can measure the thickness of the entire board, can achieve an accuracy of 2 microns, can quickly scan large-size boards, is easy to use, and can be easily integrated into existing production lines, effectively solving the problem that the board thickness cannot be fully measured, which is specifically reflected in the PCB and substrate processing process. More than ten

[0026] Where the Z value is measured, it is full range data at the same time, replacing the original backward operation method of measuring the Z value by a single point. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a schematic diagram of the process of product movement in a large-size 3D plate thickness full-scan detection method of the present invention.

[0028] Figure 2 It is a structural schematic diagram of X-axis movement in a large-size 3D plate thickness full-scan detection method of the present invention.

[0029] Figure 3 It is a structural schematic diagram of laser scanning in a large-size 3D plate thickness full-scan detection method of the present invention.

[0030] Figure 4 The figure is a schematic diagram of the process of converting signals into data and transmitting them in a large-size 3D plate thickness full-scan detection method of the present invention.

[0031] Figure 5 This is a structural schematic diagram of outputting the data required by the customer in a large-size 3D plate thickness full-scan detection method of the present invention.

[0032] Figure 6 This is a flow chart of image acquisition in a large-size 3D plate thickness full-scan detection method of the present invention.

[0033] Figure 7 This is a data processing flow chart of a large-size 3D plate thickness full-scan detection method of the present invention.

[0034] Figure 8 It is a basic structural schematic diagram of a large-size 3D plate thickness full-scan detection method of the present invention. DETAILED DESCRIPTION

[0035] In order to make the purpose, technical scheme and advantages of the present invention clearer, the present invention is further described in detail below in conjunction with specific embodiments. It should be understood that these descriptions are exemplary only and are not intended to limit the scope of the present invention. In addition, in the following description, the description of known structures and technologies is omitted to avoid unnecessary confusion of the concept of the present invention.

[0036] The following is combined with Figure 1-8 To further explain the present application in detail, a large-size 3D plate thickness full-scan detection method comprises the following steps:

[0037] Step 1: Use one or more sets of line lasers to measure up and down, obtain the output spacing L, L1, L2, and control the laser beam to move in the Z direction, and calculate the plate thickness by the formula;

[0038] Step 2: Drive the laser head to perform linear scanning through the X-axis to obtain real-time measurement data, transmit the measurement signal to the controller, convert the data, and send it to the industrial computer;

[0039] Step 3: The Y-axis servo is responsible for positioning, processing the position signal and sending it to the industrial computer;

[0040] Step 4: The dedicated algorithm software in the industrial computer receives the data from the controller and the server, summarizes and processes the collected data, and obtains the thickness information of each matrix with a minimum of 0.005*0.005 mm;

[0041] Step 5: Based on the 3D positioning algorithm, output the thickness data of the entire plate to the client.

[0042] Furthermore, in step 1, one or more groups of line lasers include two laser transmitters and two receivers, one laser transmitter and receiver are located above the board surface, and the other laser transmitter and receiver are located below the board surface.

[0043] Among them, in the step one, the laser measurement adopts the triangulation principle, and the specific measurement steps are: the laser beam is emitted from the upper transmitter to the surface of the plate, and returns to the upper receiver after reflection. At the same time, the laser beam is emitted from the lower transmitter to the surface of the plate, and returns to the lower receiver after reflection. By measuring the transmission time and incident angle of the laser beam from the transmitter to the receiver, the distance of the reflection point of the laser beam on the surface of the plate is calculated. The distance of the reflection point of the upper laser beam minus the distance of the reflection point of the lower laser beam is the plate thickness. By using one or more groups of line lasers for up and down measurements, the distance of any point on the surface of the plate can be measured, which enables the method to perform a comprehensive 3D scan of the entire plate. By using a high-precision motion control system to move the laser beam and the plate, it is ensured that the laser beam can be accurately focused on any point on the surface of the plate. This method can measure the thickness of the entire plate, while traditional single-point or multi-point measurement methods can only measure the thickness of a few points.

[0044] Wherein, in the step 1, the plate thickness calculation formula is: H = L-L1-L2;

[0045] Where H is the plate thickness; L is the laser measurement distance, that is, the distance from the laser beam from the upper transmitter to the lower receiver; L1 is the distance from the laser beam from the upper transmitter to the plate surface; L2 is the distance from the laser beam from the lower transmitter to the plate surface.

[0046] Furthermore, in the step 2, the movement range of the X-axis covers the entire width of the plate, and when the laser beam moves on the plate, the process of measuring L, L1, and L2 is repeated continuously.

[0047] Wherein, in the step 2, the real-time measurement data is a series of timestamps and distance values ​​in millimeters, and the data is transmitted to the industrial computer via a wired or wireless connection.

[0048] Furthermore, in step three, the Y-axis servo adopts a closed-loop control system to drive the motor to move and achieve precise positioning by comparing the deviation between the target position and the actual position.

[0049] Furthermore, in the step four, the board is divided into a grid, the size of each grid unit is 0.005*0.005 mm, and the thickness of each grid unit is calculated, that is, the thickness information of each minimum matrix of 0.005*0.005 mm is obtained. By dividing the board into a grid of 0.005*0.005 mm, the thickness information of each unit is refined, which helps to accurately analyze and optimize the circuit board design.

[0050] Among them, in the step 4, the dedicated algorithm software uses a linear regression algorithm to convert the laser measurement data into thickness data.

[0051] Furthermore, in the step five, the 3D positioning algorithm uses a spatial interpolation technique to generate a 3D thickness model of the entire panel according to the thickness information of each grid unit.

[0052] The present invention measures the distance of any point on the surface of the plate by using one or more groups of line lasers to perform up and down measurements, which enables the method to perform a comprehensive 3D scan of the entire plate; a single group of lasers is driven by the XY axis to move and scan a designated area for plate thickness accuracy detection, and a high-precision motion control system is used to move the laser beam and the plate, which ensures that the laser beam can be accurately focused on any point on the surface of the plate, allowing technicians to accurately understand the thickness of the plate, and accordingly optimize the circuit layout and improve the utilization of the plate surface, so that the present invention can be applied to the field of high-precision dimensional detection, such as precision device processing accuracy detection.

[0053] The present invention can measure the thickness of the entire board, can achieve an accuracy of 2 microns, can quickly scan large-size boards, is easy to use, and can be easily integrated into existing production lines, effectively solving the problem that the board thickness cannot be fully measured. It is specifically reflected in more than ten places in the PCB and substrate processing flow where Z value measurement is required. At the same time, it provides full-range data, replacing the original backward operation mode of relying on single-point measurement of Z value.

[0054] The above are only preferred embodiments of the present invention, which are only used to help understand the method and core ideas of the present application. The protection scope of the present invention is not limited to the above embodiments. All technical solutions under the concept of the present invention belong to the protection scope of the present invention. It should be pointed out that for ordinary technicians in this technical field, some improvements and modifications without departing from the principle of the present invention should also be regarded as the protection scope of the present invention. The above is only a preferred embodiment of the present invention, and it is not used to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A large-size 3D plate thickness full-scan detection method, characterized in that: The following steps are involved: Step 1: Use one or more sets of line lasers to measure up and down, obtain the output spacing L, L1, L2, and control the laser beam to move in the Z direction, and calculate the plate thickness by the formula; Step 2: Drive the laser head to perform linear scanning through the X-axis to obtain real-time measurement data, transmit the measurement signal to the controller, convert the data, and send it to the industrial computer; Step 3: The Y-axis servo is responsible for positioning, processing the position signal and sending it to the industrial computer; Step 4: The dedicated algorithm software in the industrial computer receives the data from the controller and the server, summarizes and processes the collected data, and obtains the thickness information of each matrix with a minimum of 0.005*0.005 mm; Step 5: Based on the 3D positioning algorithm, output the thickness data of the entire plate to the client.

2. A large-size 3D plate thickness full-scan detection method according to claim 1, characterized in that: In the step 1, one or more groups of line lasers include two laser transmitters and two receivers, one laser transmitter and receiver are located above the board surface, and the other laser transmitter and receiver are located below the board surface.

3. A large-size 3D plate thickness full-scan detection method according to claim 1, characterized in that: In step 1, laser measurement adopts the triangulation principle, and the specific measurement steps are as follows: The laser beam is emitted from the transmitter above to the surface of the plate, and returns to the receiver above after reflection. At the same time, the laser beam is emitted from the transmitter below to the surface of the plate, and returns to the receiver below after reflection. By measuring the transmission time and incident angle of the laser beam from the transmitter to the receiver, the distance of the laser beam reflection point on the surface of the plate is calculated. The distance of the reflection point of the upper laser beam minus the distance of the reflection point of the lower laser beam is the plate thickness.

4. A large-size 3D plate thickness full-scan detection method according to claim 1, characterized in that: In the step 1, the plate thickness calculation formula is: H = L-L1-L2; Where H is the plate thickness; L is the laser measurement distance, that is, the distance of the laser beam from the transmitter above to the receiver below; L1 is the distance of the laser beam from the emitter above to the surface of the panel; L2 is the distance of the laser beam from the emitter below to the panel surface.

5. A large-size 3D plate thickness full-scan detection method according to claim 1, characterized in that: In the step 2, the movement range of the X-axis covers the entire width of the plate, and when the laser beam moves on the plate, the process of measuring L, L1, and L2 is repeated continuously.

6. A large-size 3D plate thickness full-scan detection method according to claim 1, characterized in that: In the step 2, the real-time measurement data is a series of timestamps and distance values ​​in millimeters, and the data is transmitted to an industrial computer via a wired or wireless connection.

7. A large-size 3D plate thickness full-scan detection method according to claim 1, characterized in that: In step three, the Y-axis servo adopts a closed-loop control system to drive the motor to move and achieve precise positioning by comparing the deviation between the target position and the actual position.

8. A large-size 3D plate thickness full-scan detection method according to claim 1, characterized in that: In the step 4, the plate is divided into a grid, each grid unit has a size of 0.005*0.005 mm, and the thickness of each grid unit is calculated, that is, the thickness information of each matrix with a minimum size of 0.005*0.005 mm is obtained.

9. A large-size 3D plate thickness full-scan detection method according to claim 1, characterized in that: In the step 4, the dedicated algorithm software uses a linear regression algorithm to convert the laser measurement data into thickness data.

10. A large-size 3D plate thickness full-scan detection method according to claim 1, characterized in that: In the step five, the 3D positioning algorithm uses a spatial interpolation technique to generate a 3D thickness model of the entire panel according to the thickness information of each grid unit.

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