CN113935985A - Device and method for imaging positioning hole of PCB (printed circuit board) and related equipment - Google Patents

Device and method for imaging positioning hole of PCB (printed circuit board) and related equipment Download PDF

Info

Publication number
CN113935985A
CN113935985A CN202111287910.9A CN202111287910A CN113935985A CN 113935985 A CN113935985 A CN 113935985A CN 202111287910 A CN202111287910 A CN 202111287910A CN 113935985 A CN113935985 A CN 113935985A
Authority
CN
China
Prior art keywords
positioning hole
ink layer
pcb
color
light
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
CN202111287910.9A
Other languages
Chinese (zh)
Inventor
陈乃奇
高飞
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Shenzhen Anteland Technology Co Ltd
Original Assignee
Shenzhen Anteland Technology Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Shenzhen Anteland Technology Co Ltd filed Critical Shenzhen Anteland Technology Co Ltd
Priority to CN202111287910.9A priority Critical patent/CN113935985A/en
Publication of CN113935985A publication Critical patent/CN113935985A/en
Pending legal-status Critical Current

Links

Images

Classifications

    • G—PHYSICS
    • G06—COMPUTING; CALCULATING OR COUNTING
    • G06T—IMAGE DATA PROCESSING OR GENERATION, IN GENERAL
    • G06T7/00—Image analysis
    • G06T7/0002—Inspection of images, e.g. flaw detection
    • G06T7/0004—Industrial image inspection
    • G—PHYSICS
    • G06—COMPUTING; CALCULATING OR COUNTING
    • G06T—IMAGE DATA PROCESSING OR GENERATION, IN GENERAL
    • G06T7/00—Image analysis
    • G06T7/10—Segmentation; Edge detection
    • G06T7/13—Edge detection
    • G—PHYSICS
    • G06—COMPUTING; CALCULATING OR COUNTING
    • G06T—IMAGE DATA PROCESSING OR GENERATION, IN GENERAL
    • G06T7/00—Image analysis
    • G06T7/90—Determination of colour characteristics
    • G—PHYSICS
    • G06—COMPUTING; CALCULATING OR COUNTING
    • G06T—IMAGE DATA PROCESSING OR GENERATION, IN GENERAL
    • G06T2207/00—Indexing scheme for image analysis or image enhancement
    • G06T2207/30—Subject of image; Context of image processing
    • G06T2207/30108—Industrial image inspection
    • G06T2207/30141—Printed circuit board [PCB]

Landscapes

  • Engineering & Computer Science (AREA)
  • Computer Vision & Pattern Recognition (AREA)
  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Theoretical Computer Science (AREA)
  • Quality & Reliability (AREA)
  • Electric Connection Of Electric Components To Printed Circuits (AREA)

Abstract

The invention discloses a device and a method for imaging a positioning hole of a PCB (printed circuit board), a storage medium and related equipment, wherein the device comprises: the device comprises a color identification module, a computer, a light source module and a camera module; the color identification module identifies the color of the solder resist ink layer of the PCB and feeds back the identification result to the computer; the computer sends the control instruction to the light source module according to the identification result; the light source module respectively emits a plurality of lights with different colors or combined colors according to the control instruction, and irradiates one of the positioning holes on the PCB and the solder resist ink layer at the circumferential edge of the positioning hole; the camera module shoots an image and sends the image to the computer; and processing the image by a computer so as to fit the outline image of the positioning hole and calculate the coordinates of the circle center according to the outline image. The invention can perform high-definition imaging on the positioning hole of the PCB, so that the repeated positioning precision of the PCB is calculated more accurately.

Description

Device and method for imaging positioning hole of PCB (printed circuit board) and related equipment
Technical Field
The invention belongs to the field of PCBs (printed circuit boards), and particularly relates to a device and a method for imaging a positioning hole of a PCB and related equipment.
Background
When a laser direct imaging device is used for exposing a Printed Circuit Board (PCB), the PCB needs to be accurately placed at a preset position on a worktable, and a plurality of positioning holes are formed in the PCB for accurately positioning the PCB on the worktable.
Referring to fig. 1, when the PCB 50 reciprocates back and forth on the table 60 a plurality of times along with the X-axis and/or the Y-axis, the PCB 50 may slightly shift relative to the table 60, and at this time, the positioning holes 51 of the PCB 50 may also slightly shift relative to the table, which may deteriorate the repeated positioning accuracy of the PCB.
To detect the repeated positioning accuracy of the PCB board when the PCB board is subjected to a plurality of reciprocating movements on the table, the repeated positioning accuracy of one positioning hole 51 on the PCB board can be detected. The repeated positioning accuracy detection of the positioning hole 51 only needs to be performed by detecting the repeated positioning accuracy of the center of the positioning hole.
To measure the circle center of the positioning hole of the PCB, a high-definition image of the positioning hole is shot by the camera module, and then the circle center of the positioning hole is identified. When the image of the positioning hole is shot, a light source is needed to irradiate the positioning hole and the solder resist ink layer at the edge of the positioning hole. When the camera module shoots the positioning hole, the camera module cannot shoot the positioning hole accurately, and simultaneously, the solder resist ink layer at the edge of the positioning hole can be shot together with the camera module.
The solder mask ink layer of the PCB board has different colors, such as a common green solder mask ink layer, a red solder mask ink layer and a black solder mask ink layer. For the solder resist ink layers sprayed with different colors, if the same monochromatic light or mixed light is used for irradiating the positioning holes and the solder resist ink layers at the edges of the positioning holes, the shot images of the positioning holes have low image definition due to the fact that the color of the monochromatic light source is not matched with the color of the solder resist ink layers of the PCB, and the positioning holes and the circle centers are not easy to recognize. Therefore, in the process of repeated reciprocating motion of the PCB, when the positioning hole is irradiated by a light source which is not matched with the color of the solder resist ink layer of the PCB, the definition of a plurality of obtained images is not high, so that the contour precision of a plurality of positioning holes which are fitted according to the plurality of images is not high, and the repeated positioning value of the PCB obtained by calculation according to the plurality of positioning holes is not accurate.
Disclosure of Invention
The invention discloses a device for imaging a positioning hole of a PCB (printed circuit board), and aims to solve the problem that the repeated positioning accuracy of the PCB is not accurate according to the calculation of the circle center of the positioning hole due to low fitting accuracy of the positioning hole caused by low definition of an image of the positioning hole of the PCB shot by a camera module.
The scheme of the device is as follows:
an apparatus for imaging a locating hole of a PCB board, comprising: the device comprises a color identification module, a computer, a light source module and a camera module;
the color identification module is used for identifying the color of the solder resist ink layer of the PCB and feeding back the identification result to the computer;
the computer is used for sending the control instruction to the light source module according to the identification result;
the light source module comprises a plurality of light emitting units and mixed light units with different colors, the light source module emits emergent light matched with the color of the solder resist ink layer of the PCB according to the control instruction, and the emergent light irradiates one of the positioning holes on the PCB and the solder resist ink layer at the circumferential edge of the positioning hole;
the camera module is used for shooting an image of the solder resist ink layer comprising the positioning hole and the circumferential edge of the positioning hole and sending the image to the computer;
and the computer fits the circumferential profile of the positioning hole according to the image and calculates the circle center of the positioning hole.
Further, the colors of the solder resist ink layer of the PCB comprise white, green, black, red, yellow or blue;
the plurality of different colored light emitting units includes: the LED comprises a red light unit, a blue light unit and a green light unit; the mixed light unit is a mixed light consisting of 75% of red light and 25% of green light.
Further, the light source module sends the emergent light with the solder mask ink layer colour looks adaptation of PCB board according to control command, specifically is:
when the color of the PCB solder mask ink layer is white, the computer controls the light source module to emit red emergent light to irradiate the positioning hole and the solder mask ink layer on the edge of the positioning hole;
when the color of the PCB solder mask ink layer is green, the computer controls the light source module to emit mixed light consisting of 75% of red emergent light and 25% of green emergent light to irradiate the positioning hole and the solder mask ink layer at the edge of the positioning hole;
when the color of the PCB solder mask ink layer is black, the computer controls the light source module to emit red emergent light to irradiate the positioning hole and the solder mask ink layer at the edge of the positioning hole;
when the color of the PCB solder mask ink layer is red, the computer controls the light source module to emit mixed light consisting of 75% of red emergent light and 25% of green emergent light to irradiate the positioning hole and the solder mask ink layer at the edge of the positioning hole;
when the color of the PCB solder mask ink layer is yellow, the computer controls the light source module to emit red emergent light to irradiate the positioning hole and the solder mask ink layer at the edge of the positioning hole;
when the color of the PCB solder resist ink layer is blue, the computer controls the light source module to emit red emergent light to irradiate the positioning hole and the solder resist ink layer at the edge of the positioning hole.
Further, the color recognition module recognizes the color of the solder resist ink layer of the PCB by reading the color through an input computer or by a color sensor.
Further, the camera module is an industrial CCD camera.
The invention also discloses a method for imaging the positioning hole of the PCB board by using the device, which comprises the following steps:
step 1: the color identification module identifies the color of the solder resist ink layer of the PCB and feeds back the identification result to the computer;
step 2: the computer controls the light source module to emit emergent light matched with the color of the solder resist ink layer of the PCB according to the identification result, and the emergent light irradiates one of the positioning holes on the PCB and the solder resist ink layer at the circumferential edge of the positioning hole;
and step 3: the camera module shoots an image of the solder resist ink layer containing the positioning hole and the circumferential edge of the positioning hole and sends the image to the computer;
and 4, step 4: and the computer fits the circumferential profile of the positioning hole according to the image and calculates the circle center of the positioning hole.
Further, the light source module sends the emergent light with the solder mask ink layer colour looks adaptation of PCB board according to control command, specifically is:
when the color of the PCB solder mask ink layer is white, the computer controls the light source module to emit red emergent light to irradiate the positioning hole and the solder mask ink layer on the edge of the positioning hole;
when the color of the PCB solder mask ink layer is green, the computer controls the light source module to emit mixed light of 75% of red emergent light and 25% of green emergent light to irradiate the positioning hole and the solder mask ink layer at the edge of the positioning hole;
when the color of the PCB solder mask ink layer is black, the computer controls the light source module to emit red emergent light to irradiate the positioning hole and the solder mask ink layer at the edge of the positioning hole;
when the color of the PCB solder resist ink layer is red, the computer controls the light source module to emit mixed light consisting of 75% of red emergent light and 25% of green emergent light to irradiate the positioning hole and the solder resist ink layer at the edge of the positioning hole;
when the color of the PCB solder mask ink layer is yellow, the computer controls the light source module to emit red emergent light to irradiate the positioning hole and the solder mask ink layer at the edge of the positioning hole;
when the color of the PCB solder resist ink layer is blue, the computer controls the light source module to emit red emergent light to irradiate the positioning hole and the solder resist ink layer at the edge of the positioning hole.
Further, before step 1, the method further comprises: and moving the camera module to be positioned right above the positioning hole, or moving the PCB so that the positioning hole is positioned right below the camera module.
The invention also discloses a storage medium on which a computer program is stored, which program, when being executed by a processor, carries out the steps of the above-mentioned method.
The invention also discloses computer equipment which comprises a memory, a processor and a computer program which is stored on the memory and can run on the processor, wherein the steps of the method are realized when the processor executes the program.
The invention has the technical effects that: according to the device and the method, the color identification module identifies the color of the solder mask ink layer of the PCB and sends the identification result to the computer, the computer controls the light source module to emit monochromatic light or mixed light matched with the color of the solder mask ink layer of the PCB to irradiate one positioning hole on the PCB and the solder mask ink layer at the edge of the positioning hole according to the identification result, and the camera module shoots the solder mask ink layer at the edge of the positioning hole and the positioning hole to obtain a corresponding image. The camera module sends the image to a computer for processing, and the computer fits the circumferential contour of the positioning hole according to the image and identifies the circle center of the positioning hole. When the PCB board reciprocates, the device and the method are utilized to shoot a plurality of images of the solder mask ink layer at the circumferential edge of the same positioning hole and the circumferential edge of the positioning hole, a plurality of positioning hole circumferential profiles are fitted according to the plurality of images, the maximum discrete value of the circle centers of the plurality of positioning hole circumferential profiles calculated according to the plurality of positioning hole circumferential profiles is more accurate, and therefore the calculated repeated positioning precision of the PCB board is more accurate.
Drawings
Fig. 1 is a schematic view of a PCB board 50 placed on a work table 60;
FIG. 2 is a schematic diagram of a module connection of an apparatus for imaging a positioning hole according to a solder resist ink layer of a PCB according to the present invention;
fig. 3 is a schematic view of a positioning hole 51 and a part of a solder resist ink layer 52 located at the edge of the positioning hole 51;
FIG. 4 is a schematic diagram of the maximum discrete value of the centers 53 of two positioning holes 51 in 100 images processed by the computer;
the names and serial numbers corresponding to the components in the figure are respectively: the color recognition module 10, the computer 20, the light source module 30, the photographing module 40, the PCB 50, the positioning hole 51, the solder resist ink layer 52, and the positioning hole center 53.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, and are only for convenience of description and simplicity of description, but do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus, should not be construed as limiting the present invention; the terms "first," "second," and "third" are used merely to describe differences and are not intended to indicate or imply relative importance, and moreover, unless explicitly stated or limited otherwise, the terms "mounted," "connected," and "connected" are to be construed broadly and may, for example, be fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art.
The invention discloses a device for imaging a positioning hole of a PCB (printed circuit board), which comprises: the device comprises a color identification module, a computer, a light source module and a camera module;
the color identification module is used for identifying the color of the solder resist ink layer of the PCB and feeding back the identification result to the computer;
the computer is used for sending the control instruction to the light source module according to the identification result;
the light source module comprises a plurality of light emitting units and mixed light units with different colors, the light source module emits emergent light matched with the color of the solder resist ink layer of the PCB according to the control instruction, and the emergent light irradiates one of the positioning holes on the PCB and the solder resist ink layer at the circumferential edge of the positioning hole;
the camera module is used for shooting an image of the solder resist ink layer comprising the positioning hole and the circumferential edge of the positioning hole and sending the image to the computer;
and the computer fits the circumferential profile of the positioning hole according to the image and calculates the circle center of the positioning hole.
Referring to fig. 2, the PCB board 50 is provided with a plurality of positioning holes, one of which is named positioning hole 51. The upper end surface of the PCB 50 is covered with a solder resist ink layer 52. Referring to fig. 3, a solder resist ink layer 52 is coated on the periphery of the positioning hole 51. The solder resist ink layer 52 may be in various colors, such as white, green, black, red, yellow or blue, without limitation. Because the colors of the solder mask ink layers on the PCB are different, if the light source module 30 only emits one monochromatic light to irradiate the solder mask layers with different colors on the PCB, the definition of the image obtained by the camera module 40 by shooting the positioning hole 51 is different, and therefore the computer determines the center of the positioning hole according to the image and generates deviation. This is because, when the positioning hole 51 is photographed by the image pickup module 40, not only the image of the positioning hole 51 but also the image of the portion of the solder resist ink layer 52 located at the hole edge of the positioning hole 51 are displayed in the photographed image due to the field of view of the image pickup module 40, as shown in fig. 3. In fig. 3, if the image is not clear enough, the circumferential contour of the positioning hole 51 cannot be distinguished from the solder resist ink layer 52 at the edge of the hole in the image, and the circumferential contour of the positioning hole cannot be fitted according to the image, so that the coordinates of the center 53 cannot be calculated. Therefore, it is a prerequisite to calculate the positioning hole coordinates to take a high-definition image of the solder resist ink layer 52 including the positioning hole 51 and the edge of the positioning hole 51 as shown in fig. 3.
In the present invention, the light source module 30 includes a plurality of light emitting units or mixed light units of different colors. As one example, the light emitting units of different colors are a red light unit, a blue light unit, and a green light unit, and the mixed light unit is a mixed light composed of 75% of red light and 25% of green light.
The color recognition module 10 first recognizes the color of the solder resist ink layer 52 sprayed on the upper end of the PCB 50, and the color of the solder resist ink layer 52 may be, for example, white, green, black, red, yellow, or blue. The color recognition module 10 feeds back the recognition result to the computer 20, the computer 20 sends a control instruction to the light source module 30 according to the received recognition result, the light source module 30 sends out red light, blue light, green light or mixed light consisting of 75% of red light and 25% of green light matched with the recognized color of the solder resist ink layer, the red light, the blue light, the green light or the mixed light consisting of 75% of red light and 25% of green light irradiates the positioning hole 51 and a part of the solder resist ink layer 52 at the edge of the positioning hole 51, and the camera module 40 shoots the image of the solder resist ink layer 52 at the edge of the positioning hole 51 and the positioning hole 51.
In order to determine which monochromatic light or mixed light irradiates the PCB positioning hole and the solder resist ink layer at the edge of the positioning hole to obtain the clearest picture when the colors of the solder resist ink layers of the PCB are white, green, black, red, yellow or blue respectively, so as to fit the most accurate image of the positioning hole, the applicant performs the following experiments and obtains the data in Table 1.
Table 1: the PCB is irradiated by the solder mask layers with different colors independently by the light sources with different colors to obtain a plurality of groups of images and the maximum discrete value of the circle center of the positioning hole in each group of images.
Figure BDA0003333853860000091
The experimental contents are as follows: the PCB panel with the color of white, green, black, red, yellow or blue was irradiated with mixed light containing three monochromatic lights of red, blue and green, respectively, and red (75%) + green (25%), respectively, to obtain 4 × 7 to 28 sets of images, each including 100 images. Then, the minimum value of the center offset of the positioning hole is calculated according to each group of 100 images, and the experimental result is shown in table 1. For example, when the color of the solder resist ink layer of the PCB is white, red light is used to irradiate the positioning hole 51 and a part of the solder resist ink layer 52 at the edge of the positioning hole 51, the camera module 40 captures 100 images of the solder resist ink layer 52 including the positioning hole 51 and the outer diameter edge of the positioning hole 51, then the 100 images are sent to the computer 20 for processing, the computer 20 processes the positioning hole 51 and the circle center 53 in each image respectively from the 100 images, and finally the obtained schematic diagram of the discrete distribution of the outline and the circle center of 100 positioning holes is shown in fig. 4. Fig. 4 includes two positioning holes 53 of the images farthest from the reference line O and corresponding centers 51, and the distance between the centers 51 of the two positioning holes 53 farthest from the reference line O is the maximum discrete value of the centers. As can be seen from Table 1, when the white ink layer on the edge of the positioning hole 51 and the positioning hole 51 of the PCB were irradiated with red light, the maximum dispersion value of the center of the positioning hole was + -1.63 μm. Similarly, when the blue light is used for irradiating the positioning hole 51 of the PCB and the white ink layer at the edge of the positioning hole 51, the maximum discrete value of the circle center of the obtained positioning hole is +/-1.71 microns; when green light is used for irradiating the positioning hole 51 of the PCB and the white ink layer at the edge of the positioning hole 51, the maximum discrete value of the circle center of the positioning hole is +/-1.82 mu m; when the mixed light source of red (75%) + green (25%) is used for irradiating the positioning hole 51 of the PCB board and the white ink layer at the hole edge of the positioning hole 51, the maximum discrete value of the circle center of the obtained positioning hole is +/-1.92 microns. In summary, when the solder resist ink layer of the PCB is white, red light is used to irradiate the positioning hole 51 and the ink layer at the edge of the positioning hole 51, and the maximum discrete value of the center of the positioning hole 51 is the minimum.
According to table 1, it can be further analyzed that when the color of the solder resist ink layer of the PCB is green, the red (75%) + green (25%) mixed light is used to irradiate the positioning hole 51 and the ink layer at the edge of the positioning hole 51, and the maximum discrete value of the circle center of the positioning hole 51 in 100 images is ± 1.45 μm; when the color of the solder resist ink layer of the PCB is black, red light is used for irradiating the positioning hole 51 and the ink layer at the hole edge of the positioning hole 51, and the maximum discrete value of the circle center of the positioning hole 51 is the minimum within +/-1.24 mu m in 100 images; when the color of a solder resist ink layer of the PCB is red, a red (75%) + green (25%) mixed light source is used for irradiating the positioning hole 51 and the ink layer at the hole edge of the positioning hole 51, and the maximum discrete value of the circle center of the positioning hole 51 is the minimum within +/-1.23 mu m in 100 images; when the color of the solder resist ink layer of the PCB is yellow, red light is used for irradiating the positioning hole 51 and the ink layer at the hole edge of the positioning hole 51, and the maximum discrete value of the circle center of the positioning hole 51 is the minimum within +/-1.28 microns in 100 images; when the color of the solder resist ink layer of the PCB board is blue, red light is used for irradiating the positioning hole 51 and the ink layer at the hole edge of the positioning hole 51, and the maximum discrete value of the circle center of the positioning hole 51 is the minimum and is +/-1.33 mu m in 100 images. The smaller the maximum discrete value of the center of the positioning hole 51 is, the higher the repeated positioning accuracy of the PCB is.
From the above analysis, it can be seen that when the color of the solder resist ink layer of the PCB is white, the computer controls the light source module to irradiate the positioning hole and the solder resist ink layer at the edge of the positioning hole with the red light unit, the obtained image precision of the positioning hole is higher, and the more accurate the circumferential profile of the positioning hole is fitted according to the image; when the PCB moves repeatedly for many times, the calculated maximum discrete value of the circle center of the same positioning hole of the PCB is smaller, so that the obtained repeated positioning value of the PCB is more accurate;
when the color of the PCB solder mask ink layer is green, the computer controls the light source module to irradiate the positioning hole and the solder mask ink layer at the edge of the positioning hole with 75% of red light and 25% of green light, the obtained image of the positioning hole has higher precision, and the more precise the circumferential profile of the positioning hole is fitted according to the image; when the PCB moves repeatedly for many times, the calculated maximum discrete value of the circle center of the same positioning hole of the PCB is smaller, so that the obtained repeated positioning value of the PCB is more accurate;
when the color of the PCB solder mask ink layer is black, the computer controls the light source module to irradiate the positioning hole and the solder mask ink layer on the edge of the positioning hole by using the red light unit, and the obtained image precision of the positioning hole is higher; the obtained image precision of the positioning hole is higher, the more accurate the circumferential contour of the positioning hole is fitted according to the image, and the smaller the calculated maximum discrete value of the circle center of the same positioning hole of the PCB is when the PCB repeatedly moves for many times, so that the more accurate the obtained repeated positioning value of the PCB is;
when the color of the PCB solder mask ink layer is red, the computer controls the light source module to irradiate the positioning hole and the solder mask ink layer on the edge of the positioning hole with 75% of red light and 25% of green light, and the obtained image precision of the positioning hole is higher; the obtained image precision of the positioning hole is higher, the more accurate the circumferential contour of the positioning hole is fitted according to the image, and the smaller the calculated maximum discrete value of the circle center of the same positioning hole of the PCB is when the PCB repeatedly moves for many times, so that the more accurate the obtained repeated positioning value of the PCB is;
when the color of the PCB solder mask ink layer is yellow, the computer controls the light source module to irradiate the positioning hole and the solder mask ink layer on the edge of the positioning hole by using the red light unit, the obtained image precision of the positioning hole is higher, and the obtained image precision of the positioning hole is higher; the more accurate the circumferential contour of the positioning hole is fitted according to the image, the smaller the maximum discrete value of the circle center of the same positioning hole of the PCB is calculated when the PCB repeatedly moves for multiple times, so that the more accurate the obtained repeated positioning value of the PCB is;
when the color of the PCB solder mask ink layer is blue, the computer controls the light source module to irradiate the positioning hole and the solder mask ink layer on the edge of the positioning hole by using the red light unit, the obtained image precision of the positioning hole is higher, and the obtained image precision of the positioning hole is higher; the more accurate the circumferential contour of the positioning hole is fitted according to the image, the smaller the maximum discrete value of the circle center of the same positioning hole of the PCB is calculated when the PCB repeatedly moves for many times, and therefore, the more accurate the obtained repeated positioning value of the PCB is.
It should be noted that the above mentioned solder resist ink layer color of the PCB and the color of the monochromatic light or the mixed light are only exemplary, and the solder resist ink layer of the PCB may also be other colors, such as cyan, purple; the color of the monochromatic light may also comprise other colors, such as cyan, violet, for example. In addition, under the influence of environment, the above conclusion is not absolute, for example, when the color of the solder resist ink layer of the PCB is white, the blue light unit is used to irradiate the positioning hole and the solder resist ink layer at the edge of the positioning hole, and the definition of the obtained image of the positioning hole is higher.
It should be noted that the above-mentioned example that each group of images contains 100 pictures is only an example, and the number of pictures can be increased or decreased according to the needs, and is not limited herein.
It should be noted that, as one example, the color recognition module recognizes the color of the solder resist ink layer of the PCB by inputting the color information of the solder resist ink layer of the PCB into a computer for reading recognition or by using a color sensor. The reading and identification by the input computer may be, for example, information that the solder resist ink of the PCB is black is input to the computer, and the computer acquires the color of the solder resist ink of the PCB. As one example, the color sensor is preferably of the TCS34725 type. The color sensor and the computer 20 are connected via an expansion interface IIC. IIC (Inter-Integrated Circuit) is abbreviated as IICBus, a chinese called Integrated Circuit bus, a serial communication bus, using a multi-master-slave architecture, developed by philips in the 1980 s for connecting a motherboard, an embedded system, or a mobile phone to a low-speed peripheral device.
As one example, the camera module 40 is preferably an industrial CCD camera. The CCD is a Charge coupled Device in English, and the CCD is a Charge coupled Device in Chinese, and can also be called a CCD image sensor. A CCD is a semiconductor device that can convert an optical image into a digital signal.
The invention also discloses a method for imaging the positioning hole of the PCB by using the device, which comprises the following steps:
step 1: the color identification module identifies the color of the solder resist ink layer of the PCB and feeds back the identification result to the computer;
step 2: the computer controls the light source module to emit emergent light matched with the color of the solder resist ink layer of the PCB according to the identification result, and the emergent light irradiates one of the positioning holes on the PCB and the solder resist ink layer at the circumferential edge of the positioning hole;
and step 3: the camera module shoots an image of the solder resist ink layer containing the positioning hole and the circumferential edge of the positioning hole and sends the image to the computer;
and 4, step 4: and the computer fits the circumferential profile of the positioning hole according to the image and calculates the circle center of the positioning hole.
The color identification module in the step 1 identifies the color of the solder resist ink layer of the PCB by inputting the color information of the solder resist ink layer of the PCB into a computer for reading and identifying or by using a color sensor. As one example, the color of the solder resist ink layer of the PCB may be white, green, black, red, yellow or blue, which is not limited herein.
In step 2, the specific control method for the computer to send the control instruction to control the light source module to send out monochromatic light or mixed light with different colors according to the identification result is as follows:
when the color of the PCB solder mask ink layer is white, the computer controls the light source module to emit red emergent light to irradiate the positioning hole and the solder mask ink layer on the edge of the positioning hole;
when the color of the PCB solder mask ink layer is green, the computer controls the light source module to emit mixed light consisting of 75% of red emergent light and 25% of green emergent light to irradiate the positioning hole and the solder mask ink layer at the edge of the positioning hole;
when the color of the PCB solder mask ink layer is black, the computer controls the light source module to emit red emergent light to irradiate the positioning hole and the solder mask ink layer at the edge of the positioning hole;
when the color of the PCB solder mask ink layer is red, the computer controls the light source module to emit mixed light consisting of 75% of red emergent light and 25% of green emergent light to irradiate the positioning hole and the solder mask ink layer at the edge of the positioning hole;
when the color of the PCB solder mask ink layer is yellow, the computer controls the light source module to emit red emergent light to irradiate the positioning hole and the solder mask ink layer at the edge of the positioning hole;
when the color of the PCB solder resist ink layer is blue, the computer controls the light source module to emit red emergent light to irradiate the positioning hole and the solder resist ink layer at the edge of the positioning hole.
It should be noted that, when the colors of the inks of the solder resist layers of the PCB are different, the different monochromatic lights or mixed lights of the light source module irradiate the solder resist ink layers of the same positioning hole and the periphery of the positioning hole of the PCB.
In step 3, once the color of the solder resist ink layer of the PCB is determined, the solder resist ink layer at the circumferential edge of the positioning hole and the positioning hole is irradiated according to the corresponding emergent light in step 2, and then the camera module takes a picture of the solder resist ink layer at the circumferential edge of the positioning hole and the positioning hole. For example, when the color of the solder resist ink layer of the PCB is white, the computer controls the light source module to emit red light to irradiate the positioning hole and the solder resist ink layer at the edge of the positioning hole.
In step 4, the circumferential profile of the positioning hole is obtained by image fitting according to the boundary between the solder resist ink layer 52 and the positioning hole 51 in fig. 3.
Before step 1, the camera module needs to be moved to a position right above the positioning hole to be photographed, for example, the camera module may be mounted on a slide rail, and the camera module is moved to a position above the positioning hole on the PCB to be photographed on the slide rail; or the PCB is placed on the workbench and is moved by controlling the workbench, so that the positioning hole to be shot on the PCB is positioned right below the camera module. For example, the movement of the worktable is controlled by controlling an X-axis moving mechanism and a Y-axis moving mechanism under the worktable so as to move the PCB, so that the positioning hole of the PCB to be photographed is located under the camera module.
By utilizing the device and the method disclosed by the invention, the color identification module identifies the color of the solder mask ink layer of the PCB and sends the identification result to the computer, the computer controls the light source module to emit monochromatic light or mixed light matched with the color of the solder mask ink layer of the PCB to irradiate one positioning hole on the PCB and the solder mask ink layer at the edge of the positioning hole according to the identification result, and the camera module shoots the solder mask ink layer at the edge of the positioning hole and the positioning hole to obtain the corresponding image. The camera module sends the image to a computer for processing, and the computer fits the circumferential contour of the positioning hole according to the image and identifies the circle center of the positioning hole. When the PCB board reciprocates, the device and the method are utilized to shoot a plurality of images of the solder mask ink layer at the same positioning hole and the circumferential edge of the positioning hole of the PCB board, a plurality of positioning hole circumferential profiles are fitted according to the plurality of images, the maximum discrete value of the circle centers of the plurality of positioning hole circumferential profiles calculated according to the plurality of positioning hole circumferential profiles is more accurate, and therefore, the calculated repeated positioning precision of the PCB board is more accurate.
The invention also discloses a storage medium on which a computer program is stored, which computer program, when being executed by a processor, realizes the steps of the preceding method.
The invention also discloses a computer device comprising a memory, a processor and a computer program stored on the memory and capable of running on the processor, wherein the processor realizes the steps when executing the computer program.
Finally, it should be noted that: although the present invention has been described in detail with reference to the foregoing embodiments, it will be apparent to those skilled in the art that modifications may be made to the embodiments or portions thereof without departing from the spirit and scope of the invention.

Claims (10)

1. An apparatus for imaging a locating hole of a PCB board, comprising: the device comprises a color identification module, a computer, a light source module and a camera module;
the color identification module is used for identifying the color of the solder resist ink layer of the PCB and feeding back the identification result to the computer;
the computer is used for sending a control instruction to the light source module according to the identification result;
the light source module comprises a plurality of light emitting units and mixed light units with different colors, the light source module emits emergent light matched with the color of the solder resist ink layer of the PCB according to the control instruction, and the emergent light irradiates one of the positioning holes on the PCB and the solder resist ink layer at the circumferential edge of the positioning hole;
the camera module is used for shooting an image of the solder resist ink layer comprising the positioning hole and the circumferential edge of the positioning hole and sending the image to the computer;
and the computer is also used for fitting out the circumferential profile of the positioning hole according to the image and calculating the circle center of the positioning hole.
2. The apparatus of claim 1, wherein the color of the PCB board solder resist ink layer comprises white, green, black, red, yellow, or blue;
the plurality of different color light emitting units include: the LED comprises a red light unit, a blue light unit and a green light unit; the mixed light unit is a mixed light composed of 75% of red light and 25% of green light.
3. The apparatus according to claim 2, wherein the light source module emits an emergent light adapted to a color of a solder resist ink layer of the PCB according to the control command, specifically:
when the color of the PCB solder mask ink layer is white, the computer controls the light source module to emit red emergent light to irradiate the positioning hole and the solder mask ink layer at the edge of the positioning hole;
when the color of the PCB solder mask ink layer is green, the computer controls the light source module to emit mixed light formed by the 75% red emergent light and the 25% green emergent light to irradiate the positioning hole and the solder mask ink layer on the edge of the positioning hole;
when the color of the PCB solder mask ink layer is black, the computer controls the light source module to emit the red emergent light to irradiate the positioning hole and the solder mask ink layer at the edge of the positioning hole;
when the color of the PCB solder resist ink layer is red, the computer controls the light source module to emit mixed light of the 75% red emergent light and the 25% green emergent light to irradiate the positioning hole and the solder resist ink layer at the edge of the positioning hole;
when the color of the PCB solder mask ink layer is yellow, the computer controls the light source module to emit red emergent light to irradiate the positioning hole and the solder mask ink layer at the edge of the positioning hole;
when the color of the PCB solder mask ink layer is blue, the computer controls the light source module to emit red emergent light to irradiate the positioning hole and the solder mask ink layer at the edge of the positioning hole.
4. The apparatus of claim 1, wherein the color recognition module recognizes the color of the solder resist ink layer of the PCB in a manner of reading recognition by an input computer or recognition by a color sensor.
5. The apparatus of claim 1, wherein the camera module is an industrial CCD camera.
6. A method for imaging PCB board locating holes using the apparatus of any of claims 1 to 5, comprising the steps of:
step 1: the color identification module identifies the color of the solder resist ink layer of the PCB and feeds back the identification result to the computer;
step 2: the computer controls the light source module to emit emergent light matched with the color of the solder resist ink layer of the PCB according to the identification result, and the emergent light irradiates one of the positioning holes on the PCB and the solder resist ink layer at the circumferential edge of the positioning hole;
and step 3: the camera module shoots an image of a solder resist ink layer containing the positioning hole and the circumferential edge of the positioning hole and sends the image to the computer;
and 4, step 4: and the computer fits the circumferential profile of the positioning hole according to the image and calculates the circle center of the positioning hole.
7. The method according to claim 6, wherein the light source module emits emergent light matched with the color of the solder resist ink layer of the PCB according to the control command, specifically:
when the color of the PCB solder mask ink layer is white, the computer controls the light source module to emit red emergent light to irradiate the positioning hole and the solder mask ink layer at the edge of the positioning hole;
when the color of the PCB solder mask ink layer is green, the computer controls the light source module to emit mixed light consisting of the 75% red emergent light and the 25% green emergent light to irradiate the positioning hole and the solder mask ink layer at the edge of the positioning hole;
when the color of the PCB solder mask ink layer is black, the computer controls the light source module to emit the red emergent light to irradiate the positioning hole and the solder mask ink layer at the edge of the positioning hole;
when the color of the PCB solder resist ink layer is red, the computer controls the light source module to emit mixed light consisting of 75% of red emergent light and 25% of green emergent light to irradiate the positioning hole and the solder resist ink layer on the edge of the positioning hole;
when the color of the PCB solder mask ink layer is yellow, the computer controls the light source module to emit red emergent light to irradiate the positioning hole and the solder mask ink layer at the edge of the positioning hole;
when the color of the PCB solder mask ink layer is blue, the computer controls the light source module to emit red emergent light to irradiate the positioning hole and the solder mask ink layer at the edge of the positioning hole.
8. The method of claim 6, prior to step 1, further comprising: and moving the camera module to be positioned right above the positioning hole, or moving the PCB so that the positioning hole is positioned right below the camera module.
9. A storage medium on which a computer program is stored, which program, when being executed by a processor, carries out the steps of the method according to any one of claims 6 to 8.
10. A computer device comprising a memory, a processor and a computer program stored on the memory and executable on the processor, characterized in that the steps of the method according to any of claims 6 to 8 are implemented when the program is executed by the processor.
CN202111287910.9A 2021-11-02 2021-11-02 Device and method for imaging positioning hole of PCB (printed circuit board) and related equipment Pending CN113935985A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202111287910.9A CN113935985A (en) 2021-11-02 2021-11-02 Device and method for imaging positioning hole of PCB (printed circuit board) and related equipment

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202111287910.9A CN113935985A (en) 2021-11-02 2021-11-02 Device and method for imaging positioning hole of PCB (printed circuit board) and related equipment

Publications (1)

Publication Number Publication Date
CN113935985A true CN113935985A (en) 2022-01-14

Family

ID=79285478

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202111287910.9A Pending CN113935985A (en) 2021-11-02 2021-11-02 Device and method for imaging positioning hole of PCB (printed circuit board) and related equipment

Country Status (1)

Country Link
CN (1) CN113935985A (en)

Similar Documents

Publication Publication Date Title
CN107945184B (en) Surface-mounted component detection method based on color image segmentation and gradient projection positioning
CN108700409B (en) Three-dimensional measuring device
US20150130925A1 (en) Contactless component-inspecting apparatus and component-inspecting method
KR101241175B1 (en) Mounting boards inspection apparatus and method thereof
US20080062266A1 (en) Image test board
CN108093618B (en) Inspecting mounting contents by comparing 3D height profile with reference height profile
JPH061173B2 (en) Curved property inspection device
JP4883636B2 (en) Electronic component orientation inspection apparatus, electronic component orientation inspection method, and electronic component placement machine
CN113935985A (en) Device and method for imaging positioning hole of PCB (printed circuit board) and related equipment
KR101079686B1 (en) Image recognition apparatus and image recognition method
CN110744920B (en) Method and system for positioning printed product
US9756230B2 (en) Mounting and inspection data creation device and mounting and inspection data creation method
KR101897043B1 (en) Optical inspection apparatus for performing automatic illumination processing and optical inspection method using the apparatus
JP2782759B2 (en) Solder appearance inspection device
KR101825832B1 (en) Automatic handling device for applied in a multilayer circuit board drill machine
WO2022003919A1 (en) Inspection data preparation method, inspection data preparation device, and inspection device
CN115136579B (en) Image correction method, imaging device and inspection device
JP2004273774A (en) Printing device for substrate
CN112857234A (en) Measuring method and device for combining two-dimensional and height information of object
JP2004264026A (en) Image recognition device and method
KR101736060B1 (en) Inspection method
CN115412719B (en) Method for aligning camera lens and light source
CN113545185B (en) Object determination method and object determination device
KR20240026427A (en) Image capturing apparatus, substrate inspection apparatus, image capturing method, and substrate inspection method
Heinemann et al. Single image camera calibration in close range photogrammetry for solder joint analysis

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination