CN114609150A

CN114609150A - PCB optical detection device

Info

Publication number: CN114609150A
Application number: CN202210214890.0A
Authority: CN
Inventors: 甘珍贵
Original assignee: Dongguan Meng Tuo Intelligent Technology Co ltd
Current assignee: Dongguan Meng Tuo Intelligent Technology Co ltd
Priority date: 2022-03-03
Filing date: 2022-03-03
Publication date: 2022-06-10

Abstract

The application discloses PCB optical detection device belongs to optical detection technical field. The PCB optical detection device of the application comprises: the conveying device is used for conveying the PCB and comprises a plurality of rollers; the first shooting device is arranged below the gap between the two adjacent rollers and is used for shooting the lower surface area of the PCB between the two adjacent rollers; at least one group of illuminating devices, wherein each group of illuminating device comprises a reflecting plate and a light source; the reflector is arranged between two adjacent rollers and positioned on one side of the axis of the first shooting device, and a reflecting surface is formed on the reflector and is a rough surface; the light source sets up in running roller below and is located first shooting device's axis opposite side, and the light source is used for towards reflection of light surface emission light, and reflection of light surface is used for light diffuse reflection to PCB. The PCB optical detection device is characterized in that the incident light on the surface of the PCB is low-angle light, so that the brightness of the shooting position is uniform, and the detection accuracy is effectively improved.

Description

PCB optical detection device

Technical Field

The application relates to the technical field of optical detection, in particular to a PCB optical detection device.

Background

In the field of PCB manufacturing, in order to improve the detection efficiency of the outgoing PCB, the following detection scheme is provided for the detection of the PCB. Namely, a conveying device is arranged and used for conveying the PCB; the conveying device comprises a plurality of rollers, and the rollers are arranged at intervals, so that gaps are formed among the rollers; meanwhile, a shooting device and a light source are arranged below the conveying plane of the conveying device, the light source is used for illuminating the area, located between the two rollers, of the PCB, and the shooting device is used for acquiring the illuminated area of the PCB. According to the detection scheme, although the PCB can be detected in the PCB conveying process, due to the fact that the light source is blocked by the roller, the light source can only enter the surface of the PCB at a high angle, and when the surface of the PCB is convex, the brightness of the picture acquired by the shooting device is uneven, and therefore detection precision is affected.

Disclosure of Invention

The present application is directed to solving one of the technical problems in the prior art. Therefore, the PCB optical detection device is provided, and light incident on the surface of the PCB is low-angle light, so that the brightness of a shooting position is uniform, and the detection accuracy is effectively improved.

The PCB optical detection device comprises:

the conveying device comprises a plurality of rollers and is used for conveying the PCB;

the first shooting device is arranged below a gap between two adjacent rollers and is used for shooting the lower surface area of the PCB between the two adjacent rollers;

at least one set of illuminating devices, each set of illuminating devices comprising a reflector and a light source; the reflector is arranged between two adjacent rollers and positioned on one side of the axis of the first shooting device, and a reflecting surface is formed on the reflector and is a rough surface; the light source is arranged below the roller and on the other side of the axis of the first shooting device, the light source is used for emitting light towards the light reflecting surface, and the light reflecting surface is used for diffusely reflecting the light to the PCB.

According to the PCB optical detection device of the embodiment of the application, the PCB optical detection device at least has the following beneficial effects:

set up conveyer, conveyer comprises a plurality of running rollers to, set up first shooting device in the planar below of conveying, make PCB can detect at the in-process of conveying, thereby effectively improve detection rate. Further, set up the reflector panel between two adjacent running rollers of conveying plane below, set up the light source simultaneously, the reflector panel is used for the incident light diffuse reflection with the light source to PCB's bottom surface for light can be with as low as possible angle penetrate to PCB on, avoid incident angle too big lead to the light reflection and cause the interference to the shooting of first shooting device, thereby be favorable to improving and detect the rate of accuracy.

According to some embodiments of the application, the reflector plate is arranged obliquely with respect to a transport plane of the transport device.

According to some embodiments of the present application, the reflector is made of a high reflectivity material.

According to some embodiments of the present application, the reflector is made of a high strength material.

According to some embodiments of the application, the illumination device is provided in two groups.

According to some embodiments of the application, the two sets of illumination devices are symmetrically disposed along an axis of the first camera.

According to some embodiments of the present application, a direct light source is provided between the two sets of said illumination devices, said direct light source illuminating on said PCB.

According to some embodiments of the application, the light source is a linear light source.

According to some embodiments of the present application, a second photographing device for photographing an upper surface of the PCB is further provided above a conveying plane of the conveying device.

According to some embodiments of the present application, the first camera and the second camera are line scan cameras.

Additional aspects and advantages of the present application will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the present application.

Drawings

The above and/or additional aspects and advantages of the present application will become apparent and readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings of which:

fig. 1 is a perspective view of an optical inspection apparatus for a PCB according to an embodiment of the present application.

Fig. 2 is a side view of an optical inspection device for a PCB according to an embodiment of the present application.

Fig. 3 is a schematic diagram showing a PCB when it is exposed to high angle light.

Fig. 4 is a schematic diagram showing a PCB being illuminated by low-angle light.

FIG. 5 is a schematic diagram showing a PCB being illuminated by high and low angle mixed light.

Fig. 6 is a side view of an optical inspection device for PCBs in an alternative embodiment of the present application.

Detailed Description

Reference will now be made in detail to the embodiments of the present application, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below with reference to the drawings are exemplary only for the purpose of explaining the present application and are not to be construed as limiting the present application.

In the description of the present application, it is to be understood that the positional descriptions, such as the directions of up, down, left, right, front, rear, and the like, referred to as positional or positional relationships are based on the directions or positional relationships shown in the drawings, and are only for convenience of description and simplification of description, but do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and thus, should not be construed as limiting the present application.

In the description of the present application, unless otherwise expressly limited, terms such as set, mounted, connected and the like should be construed broadly, and those skilled in the art can reasonably determine the specific meaning of the terms in the present application by combining the detailed contents of the technical solutions.

The PCB optical inspection apparatus of the present application is described below with reference to fig. 1 to 6.

Referring to fig. 1 to 5, the PCB optical inspection apparatus of the present application includes:

a conveyer including a plurality of rollers 100, the conveyer for conveying the PCB 200;

the first photographing device 510 is disposed below the gap between two adjacent rollers 100, and the first photographing device 510 is configured to photograph a lower surface area of the PCB200 between the two adjacent rollers 100;

at least one set of illumination devices, each set of illumination devices comprising a reflector 300 and a light source 400; the reflector 300 is disposed between two adjacent rollers 100 and located on one side of the axis of the first photographing device 510, and a reflective surface is formed on the reflector 300, and the reflective surface is a rough surface; the light source 400 is disposed below the roller 100 and on the other side of the axis of the first photographing device 510, the light source 400 is configured to emit light toward the reflective surface, and the reflective surface is configured to diffusely reflect the light to the PCB 200.

It is understood that the transfer device may be disposed between two adjacent stations to connect two adjacent processing steps of the PCB 200.

The conveying device is composed of a plurality of rollers 100, gaps are formed between the rollers 100, and the lower surface of the PCB200 can be shot and detected by arranging the first shooting device 510 below the gap between every two adjacent rollers 100, so that the upper surface and the lower surface of the PCB200 can be shot and detected in the conveying process, and the detection speed is favorably improved; and, so set up, need not to set up the detection station alone to PCB200 extra, can realize the detection to PCB200 upper and lower surface simultaneously, consequently, PCB200 detection device's simple structure, low cost.

Further, since the detection area of the lower surface of the PCB200 is located between two adjacent rollers 100, the brightness of the detection area of the lower surface of the PCB200 is low, and the first camera 510 cannot accurately acquire an image of the detection area, so that the detection error rate is high. For this, in order to improve the brightness of the PCB200 detection area, an illumination device for illuminating an area of the PCB200 between two adjacent rollers 100 is disposed below the conveying plane of the conveyor.

Specifically, the illuminating device includes a reflector 300 disposed on one side of the axis of the first camera 510 and a light source 400 disposed on the other side of the axis of the first camera 510, it is to be understood that the reflective surface on the reflector 300 is rough, so that incident light can be diffusely reflected on the reflective surface, and thus can be reflected onto the PCB200 at high and low angles at the same time, so that the brightness of the detection area on the PCB200 is uniform.

Specifically, referring to fig. 3 to 5, fig. 3 to 5 are schematic diagrams of optical paths in the case of non-diffuse reflection. Fig. 3 is a schematic diagram of an optical path of light reflected by the PCB200 under high-angle light irradiation, as can be seen from fig. 3, at the protrusion of the PCB200, only one group of light is reflected along the direction parallel to the axis of the photographing device after two groups of parallel lights irradiate the protrusion of the PCB200, the other group of light is reflected at a certain angle with the axis of the first photographing device 510, if the two groups of reflected lights are incident into the first photographing device 510, because the two groups of reflected lights are not parallel to each other, the brightness of the two groups of reflected lights is inconsistent, and further the brightness of the imaging image in the first photographing device 510 is uneven, which affects the detection accuracy. Fig. 4 is a schematic diagram of an optical path of light reflected by the PCB200 under the low-angle light irradiation, and as can be seen from fig. 4, the low-angle light can make the light irradiate on the convex edge of the PCB200 and then enter the photographing device in a direction parallel to the axis of the first photographing device 510. Therefore, in order to make the brightness of the projection on the PCB200 uniform, a plurality of groups of lights with different angles are generally set at the same time, and limited by the structural limitation of the roller 100, and the low-angle light with too low angle will be blocked by the roller 100 and thus cannot irradiate on the PCB 200.

Therefore, in order to allow the light source 400 to irradiate the PCB200 at a high angle and a low angle at the same time, the reflection plate 300 is disposed between two adjacent rollers 100, and the reflection surface of the reflection plate 300 is a rough surface. The light emitted from the light source 400 is incident on the reflection plate 300 and then diffusely reflected by the reflection plate 300 to the detection area of the PCB 200. Referring to fig. 5, through diffuse reflection, the light source 400 can irradiate the detection area on the PCB200 at a low angle and a high angle at the same time, that is, the light reflected by the light reflecting surface can irradiate the protrusions on the PCB200 at a plurality of angles, so that a plurality of groups of reflected lights can be incident into the first camera 510 in a direction parallel or nearly parallel to the axis of the first camera 510, thereby effectively avoiding interference of the light on the PCB200 due to specular reflection of the light on the PCB200 caused by the high-angle light irradiating the PCB200, and also enabling the edges of the protrusions on the PCB200 to be uniformly illuminated. Further, the edge of the light reflection plate 300 is located as close to the transmission plane of the transmission device as possible, so that the light reflection plate 300 can provide light with a low angle as possible, thereby enabling the first photographing device 510 to photograph the detection area of the PCB200 more clearly and accurately.

This application is through above-mentioned setting to make PCB200 go up detection area's luminance more even, can avoid local high bright to cause the interference to first shooting device 510, perhaps local luminance is not enough to lead to unable accurate aassessment quality, is favorable to improving and detects the precision, and then improves and detect the rate of accuracy.

Referring to fig. 1 and 2, in some embodiments of the present application, the light reflecting plate 300 is disposed obliquely with respect to a conveying plane of the conveying apparatus.

It is understood that the reflector 300 is configured such that more light rays from the same light source 400 are irradiated onto the reflector 300; further, the included angle between the light reflection plate 3000 and the transmission plane is an acute angle, and further, the acute angle may be an included angle smaller than 45 °. By the arrangement, the utilization rate of the light source 400 can be improved, the brightness of the detection area on the PCB200 can be further improved, and the detection precision can be improved.

Referring to fig. 3, in some embodiments of the present application, the reflector 300 is made of a high reflectance material. For example, the metal material is preferably an alloy metal material having high strength such as stainless steel. Through so setting up, can improve the reflectivity of light, choose for use under the less light source 400 of power for use, the luminance of PCB200 check out test area can satisfy the detection demand to can reduce PCB optical detection device's manufacturing cost.

Referring to fig. 3 and 4, in some embodiments of the present application, the illumination devices are provided in two groups. Specifically, the two sets of illumination devices may be symmetrically disposed along the axis of the first camera 510 or asymmetrically disposed.

When two sets of irradiation device symmetry set up, reflector panel 300 among two sets of irradiation device is close to two adjacent running roller 100 settings respectively, light source 400 corresponds among every group irradiation device and shines on reflector panel 300 among each group irradiation device, thereby can reduce the luminance difference of the protruding both sides on the PCB200 detection area, avoid protruding certain one side highlight and the condition that the opposite side luminance is too dark to appear, thereby make the luminance of the protruding both sides on the PCB200 detection area even, be favorable to improving shooting device's detection accuracy.

When the two sets of irradiation devices are asymmetrically arranged, the reflectors 300 in the two sets of irradiation devices may be symmetrically arranged, but the light sources 400 in the two sets of irradiation devices are asymmetrically arranged, that is, the incident angles of the light sources 400 in the two sets of irradiation devices are different, so that the ratio of high-angle light and low-angle light incident on the reflector 300 can be realized by adjusting the brightness difference of the light sources 400 in the two sets of irradiation devices, and thus different brightness irradiation requirements can be realized.

Referring to fig. 6, in some embodiments of the present application, a direct light source 600 is disposed between two sets of illumination devices, the direct light source 600 illuminating on the PCB.

It will be appreciated that the direct light source 600 is disposed between two sets of illumination devices, and thus the angle between the direct light source 600 and the PCB is relatively large, specifically the angle between the direct light source 600 and the PCB may be greater than 45 °, and in some cases, may also be 90 °. So set up, when reflector panel 300 can provide low angle light to PCB200, direct light source 600 can provide high angle light to PCB200, and high angle light and low angle light cooperate each other to can be applicable to more models of being surveyed PCB200, the suitability is wider.

Referring to fig. 5, in some embodiments of the present application, a second photographing device 520 is further provided above a conveying plane of the conveying device, the second photographing device 520 being used to photograph an upper surface of the PCB 200.

It can be understood that the second photographing device 520 is disposed above the transfer plane of the transfer device, and when the PCB200 is moved on the transfer plane by the transfer device, the second photographing device 520 can photograph the PCB200 passing thereunder, thereby performing photographing detection of the upper surface of the PCB200 during the transfer of the PCB 200.

Referring to fig. 5, in some embodiments of the present application, the light source 400 is a line light source 400, and the first camera 510 and the second camera 520 are line scan cameras.

Specifically, the light source 400 is a line light source 400, and the light source 400 has a long length and uniform brightness, thereby being suitable for the PCB200 having a wide width. Further, the light source 400 may select the light source 400 that can be focused, so that the focal point of the light beam can be located on the reflective surface of the reflector 300, and thus the reflector 300 can diffusely reflect more light to the detection area on the PCB200, which improves the utilization rate of the light source 400, and thus can improve the optical efficiency. Meanwhile, the second photographing device 520 is a line scanning camera. It is understood that the first camera 510 may also be a line scan camera.

Specifically, the operation process of the PCB optical inspection apparatus in the present application is as follows:

the conveying device continuously drives the PCB200 thereon to advance, in the process, the two groups of light sources 400 are simultaneously started and irradiate the reflector 300, the reflector 300 diffusely reflects the light of the light sources 400 to the detection area on the PCB200, the light is reflected on the PCB200 again so as to enter the first shooting device 510 and form an image, and meanwhile, the second shooting device 520 also shoots and forms an image on the upper surface of the PCB 200.

The embodiments of the present application have been described in detail with reference to the drawings, but the present application is not limited to the embodiments, and various changes can be made within the knowledge of those skilled in the art without departing from the gist of the present application.

Claims

1. An optical inspection apparatus for a PCB, comprising:

the first shooting device is arranged below a gap between every two adjacent rollers and is used for shooting the lower surface area of the PCB between every two adjacent rollers;

2. The PCB optical inspection device of claim 1, wherein: the reflector is obliquely arranged relative to the conveying plane of the conveying device.

3. The PCB optical inspection device of claim 1, wherein: the reflector is made of a high-reflectivity material.

4. The PCB optical inspection device of claim 1, wherein: the reflector is made of high-strength material.

5. The PCB optical inspection device of claim 1, wherein: the irradiation devices are provided with two groups.

6. The PCB optical inspection device of claim 5, wherein: the two groups of the irradiation devices are symmetrically arranged along the axis of the first shooting device.

7. The PCB optical inspection device of claim 5, wherein: and a direct light source is arranged between the two groups of irradiation devices, and the direct light source irradiates the PCB.

8. The PCB optical inspection device of claim 1, wherein: the light source is a linear light source.

9. The PCB optical inspection device of claim 1, wherein: and a second shooting device is also arranged above the conveying plane of the conveying device and is used for shooting the upper surface of the PCB.

10. The PCB optical inspection device of claim 9, wherein: the first photographing device and the second photographing device are line scanning cameras.