Feature detection lighting dome

Abstract

A feature detection lighting system includes a housing having a first end provided with a mounting structure and a second end defining a peripheral profile. An inner surface is arranged between the first end and the second end of the outer cover, and a protruding surface is defined on the inner surface. The light sources are fixed to the protruding surfaces of the inner surface of the outer cover, and the power supply cable is arranged between the protruding surfaces of the outer cover. The outer edge of the outer cover can be provided with a notch through which all or part of an object to be detected can pass.

Description

[0001] Priority Declaration

[0002] This application claims the benefit of priority to U.S. patent application No. 17 / 972,373, filed on October 24, 2022, the entire contents of which are incorporated herein by reference. Technical Field

[0003] The present application relates to the field of detection systems and light sources thereof, and in particular to the technology in some embodiments. Background Art

[0004] In manufacturing quality control processes, especially in high-volume production, camera-based imaging systems are often implemented to capture images of parts for automated defect scanning. In fly-by applications, where the part is not stopped in front of the camera, high-speed cameras are required to capture and illuminate the part to ensure a clear, blur-free image. This sometimes requires a combination of different light channels. BRIEF DESCRIPTION OF THE DRAWINGS

[0005] To facilitate identification of discussions of a particular element or operation, the most significant digit(s) in a reference number indicates the drawing number in which the element first appears.

[0006] Figure 1 A block diagram of a detection system according to some embodiments is shown.

[0007] Figure 2 According to some embodiments Figure 1 A perspective view of the lighting dome in the inspection system.

[0008] Figure 3 According to some embodiments Figure 2 A perspective view of the underside of the light dome, showing the printed circuit board (PCB) layout containing the light sources.

[0009] Figure 4 According to some embodiments Figure 2 A perspective view of the underside of the light dome, showing the power cable routing.

[0010] Figure 5 According to some embodiments Figure 2 A perspective view of the light dome's underside, including the inner cover structure.

[0011] Figure 6 According to some embodiments Figure 2 A perspective view of the light dome's underside, including the fixed diffuser.

[0012] Figure 7 According to some embodiments Figure 2 A perspective view of the underside of the light dome, including the removable diffuser.

[0013] Figure 8 According to some embodiments Figure 2 A three-dimensional image of the underside of the light dome further illustrates the light source layout.

[0014] Figure 9 According to some embodiments Figure 2 Schematic diagram of the distribution of light sources in the light dome.

[0015] Figure 10 and 11 A perspective view illustrating another dome shape according to some embodiments is shown.

[0016] Figure 11 According to some embodiments Figure 10 A perspective view of the underside of the dome cover.

[0017] Figure 12 According to some embodiments Figure 10 A floor plan of the dome array.

[0018] Figure 13 A perspective view of a light dome is shown, according to some embodiments.

[0019] Figure 14 According to some embodiments Figure 13 Partial exploded perspective view of the dome.

[0020] Figure 15 According to some embodiments Figure 13 A perspective view of the dome shell. DETAILED DESCRIPTION

[0021] In industrial production, image recognition is used to detect surface features of products (such as metal castings). However, when the product has a specific surface material, specific features and / or a specific detection environment, it is often difficult for existing light sources to achieve ideal imaging when capturing images. For example, material properties that affect the quality of imaging light include reflectivity, transparency, or black / opacity. In addition, a specific light source may not be compatible with the imaging of different types of features, including actual product features (such as points, lines, circles, etc.) and manufacturing defects or unexpected features (such as scratches or stains). In other cases, a specific light source may not be able to generate satisfactory images in different environments (such as laboratories or production lines). The light quality of the captured image directly affects the ability to detect product surface features, and insufficient light quality will lead to a decrease in feature recognition accuracy.

[0022] As mentioned above, current industrial product image acquisition faces many challenges related to light sources. For different surface materials such as reflective, transparent or black, traditional methods require light sources to emit light of multiple wavelengths and modes in order to obtain high-quality images. In addition, traditional single light sources cannot provide sufficient illumination for imaging of multiple types of features such as product features, scratches, stains (as well as features with random positions, sizes or shapes). This type of imaging usually requires a customized light source with a specific incident angle and light pattern. Finally, because different environments (such as laboratories and production lines) usually produce products of different materials under different ambient lighting conditions, traditional light sources find it difficult to provide sufficient illumination for image acquisition in different environments (such as laboratories and production lines). Therefore, in order to obtain high-quality images sufficient to detect features, traditional methods require manual adjustment of the distance and geometric position relationship between the light source, camera and product.

[0023] In some embodiments, the present disclosure utilizes customizable lighting configurations that provide adjustable incident angles, light patterns, and wavelengths through a single light source assembly. This light source assembly can adequately illuminate the product for high-quality image capture under a variety of conditions, such as varying surface materials, feature types, and environments.

[0024] In some embodiments, a feature detection lighting system is provided, comprising a housing having a mounting structure at a first end and defining a peripheral contour at a second end. The housing includes an inner surface between the first and second ends, and a plurality of light sources are disposed on the inner surface of the housing. The peripheral contour of the housing may include an opening through which all or part of an object to be detected can pass. The plurality of light sources may include at least ten independently addressable light sources.

[0025] The plurality of light sources may be secured to the housing via flexible substrates, each flexible substrate comprising a plurality of light sources. In some embodiments, the flexible substrates may be mounted on raised surfaces defined on the inner surface of the housing. Each flexible substrate may be provided with a connector for electrically connecting the light sources to a power source. The feature detection lighting system may further include a cable connecting the connector to the power source, the cable being routed behind the flexible substrates between the raised surfaces.

[0026] In some embodiments, the feature detection lighting system includes an inner housing connected to an outer housing, the inner housing having light-transmitting holes corresponding to the positions of the plurality of light sources. A fixed diffuser may be further connected to the outer housing, and a detachable diffuser may be superimposed and mounted above the fixed diffuser and connected to the outer housing.

[0027] In some embodiments, a feature detection lighting system includes a housing having a mounting structure at a first end and defining an outer contour at a second end. The housing includes an inner surface between the first and second ends, the inner surface having a plurality of raised surfaces. A plurality of light sources are disposed on the raised surfaces of the housing inner surface, and cables for powering the plurality of light sources are routed between the raised surfaces of the housing.

[0028] The plurality of light sources may be fixed to the raised surfaces via a flexible substrate, and the cables are arranged between the raised surfaces below the flexible substrate. In some embodiments, the plurality of light sources may include at least ten independently addressable light sources.

[0029] The outer contour of the housing may be substantially rectangular and have four corner regions. The plurality of light sources may be arranged in a plurality of annular regions between the mounting structure and the outer contour, with each corner region having an additional light source.

[0030] The above system may further include an inner cover connected to the outer cover, wherein the inner cover is provided with light-transmitting holes corresponding to the positions of the plurality of light sources.

[0031] The feature detection lighting system further comprises a fixed diffuser fixedly connected to the outer cover, and the detachable diffuser can be superimposed and installed above the fixed diffuser and connected to the outer cover.

[0032] The outer contour of the housing may be provided with an opening, and all or part of the object to be detected can pass through the opening.

[0033] Those skilled in the art can easily learn other technical features from the following drawings, descriptions and claims.

[0034] According to some embodiments, Figure 1 FIG2 is a block diagram of an inspection system 100 according to some embodiments. The inspection system 100 includes a light dome 102, a camera 108, a controller 106, an industrial computer 112, and a factory computer 116. The factory computer 116 communicates with the controller 106 and the industrial computer 112 via a wired or wireless factory network 124.

[0035] When in use, the light dome 102 illuminates a target object 104 (e.g., a metal casting or other manufactured product). The light dome 102 comprises a housing structure housing multiple light sources, details of which will be described below. In some embodiments, the multiple light sources comprise multiple LEDs or display screens, arranged to provide flexible illumination of the target object 104. The multiple light sources are selectively activated by a controller 106 via a power cord 110. A single light source is the smallest lighting unit that can be individually addressed by the controller 106 to illuminate the target object 104. Thus, a single light source may comprise a single LED or multiple addressable LEDs in groups. The multiple light sources may also comprise subunits of a light-emitting device, such as a group or block of pixels in a flexible display screen. Preferably, the light dome 102 is equipped with at least ten independently addressable light sources to provide lighting flexibility.

[0036] The camera 108 can be mounted on the light dome 102 via a bracket 114 and photograph the illuminated object 104 through the opening at the top of the light dome 102. The camera 108 is triggered by the controller 106 via a trigger signal line 118, and its triggering timing is synchronized with the activation of the light source in the light dome 102.

[0037] The controller 106 controls the operation of the camera 108 and the illumination of the target 104 by the light dome 102. The controller 106 receives instructions from the industrial computer 112 via control circuit 122. The controller 106 may be implemented as a hardware processor within the camera 108 and may further include a combination of the following hardware components: a central processing unit (CPU), a bus, volatile and non-volatile storage devices, a storage unit, non-transitory computer-readable media, a data processor, a processing device, a control device, a transmitter, a receiver, an antenna, a transceiver, an input device, an output device, and a network interface device (other component types will be apparent to those skilled in the art). The hardware components within the user device can be used to independently execute the various applications, methods, or algorithms disclosed herein.

[0038] The controller 106 illuminates the target object according to one or more optimal lighting configurations. These one or more optimal lighting configurations can be defined in a matrix format, where each value in the lighting configuration matrix represents the operating state of a separately controllable light source (e.g., one or more LEDs and / or pixel clusters on a flexible display). The matrix can also include brightness or color values for a specific configuration. The one or more optimal lighting configurations can also be arranged into a configuration sequence, which specifies the order in which the lighting configurations should be executed for a particular target object 104, thereby enabling the camera 108 to capture multiple images under different lighting conditions.

[0039] The industrial computer 112 runs software that provides a user interface for configuring lighting configurations and sequences and for loading these configurations and sequences into the controller 106. The industrial computer 112 also sends operating instructions to the controller 106 via a control line 122 and receives images captured by the camera 108 via a data line 120.

[0040] The factory computer 116 performs overall factory-level control and receives operational data and captured images from the controller 106 and the industrial computer 112 via the factory network 124. The factory computer 116 can also issue commands based on other factory operations (e.g., the movement of the target 104 beneath the light dome 102) to control or initiate the operation of the inspection system 100.

[0041] According to some embodiments, Figure 2 Shown Figure 1 The three-dimensional structure of the visible light dome 102. The visible light dome 102 includes an outer housing 202 having a mounting ring 206 for mounting the camera 108. The mounting ring 206 is disposed around the upper edge of a defining ring 208. The defining ring 208 defines an opening at the first end (i.e., the upper end) of the light dome 102, allowing the camera 108 to observe the target 104 through the opening.

[0042] The light dome 102 is further provided with two cable outlets 204 through which power cables 110 pass to power the light sources within the light dome 102. The cable outlets 204 are located in one or more corner areas of the light dome 102 to free up more space for the cameras 108 on the mounting ring 206 and increase layout flexibility.

[0043] In some embodiments, the light dome 102 includes four lower sidewalls 210. Each lower sidewall has a lower edge or outer contour 216 at the second (i.e., lower) end of the light dome 102. This outer contour 216 includes an opening 212 for passage of all or part of an object 104 (e.g., placed on a conveyor belt). The opening 212 allows the light dome 102 to be mounted closer to the object 104 or conveyor belt while effectively shielding it from ambient light interference. As shown, the outer contour 216 is generally rectangular (square in the illustrated embodiment).

[0044] Figure 2 Also shown are several grooves 214 on the housing 202, which correspond to the raised island structures on the inner surface of the housing 202 where the light sources can be mounted. In some embodiments, the housing 202 is made of metal to achieve good heat conduction properties between the light sources and the upper surface of the housing 202.

[0045] According to some embodiments, Figure 3 Shown Figure 2The three-dimensional structure of the bottom of the central light dome 102 shows the arrangement of the printed circuit board (PCB) containing the light sources (such as LEDs). In this view, part of the PCB is removed to show the structural details of the bottom of the outer cover 202 and the positioning of the LEDs.

[0046] The bottom of the light dome 102 is generally hemispherical. According to some embodiments, four T-shaped PCBs 302 and four L-shaped PCBs 304 are mounted on the bottom of the light dome 102. In this view, the L-shaped PCB 304 on the lower left and the T-shaped PCB 302 on the left are not shown.

[0047] Each printed circuit board (PCB) includes a substrate 306, a connector 310, and multiple high-power LEDs 308. These high-power LEDs, under the control of the controller 106, provide selective illumination of the target 104 under test. As shown, the bottom of the housing 202 is provided with multiple raised pads 312. These raised pads form a raised surface on the bottom of the housing 202 that supports the T-shaped PCB 302 and the L-shaped PCB 304. The positions of the raised pads 312 correspond one-to-one with the multiple high-power LEDs 308, and thermal paste is applied between each raised pad 312 and the multiple high-power LEDs 308 to facilitate heat transfer from the LED to the light dome 102.

[0048] A routing channel 314 is formed between the raised pads 312, through which the power line 110 is routed from the connector 310 to the cable outlet 204. The power line 110 passes through the routing channel 314 from under the adjacent PCB.

[0049] According to some embodiments, Figure 4 Shown Figure 2 The power cable 110 is routed at the bottom of the central light dome 102. The power cable 402 extends from the connector 406 of the T-shaped PCB 404 and the connector 410 of the L-shaped PCB 414 to the cable outlet 204. The power cable 402 then passes underneath the L-shaped PCB 408 through the routing channel 314 between the raised pads 312 mounted thereon.

[0050] Similarly, the power line 416 is led out from the connector 412 of the L-shaped PCB 408 to the cable outlet 204 and passes through one of the routing channels 314 and underneath another L-shaped PCB (not shown).

[0051] The above-mentioned arrangement of the PCB and corresponding LEDs, together with the cable routing between the raised pads 312 , form a compact structural layout while ensuring that the heat of the LEDs 308 is efficiently transferred to the housing 202 .

[0052] According to some embodiments, Figure 5 Shown Figure 2The bottom of the central light dome 102 includes an inner cover 502. This inner cover 502 is mounted on the outer cover 202 and has multiple light-transmitting holes 504, allowing light from the LEDs 308 to pass through and provide the required illumination. The inner cover 502 also seals the PCB and power cable 110 within the space between the outer and inner covers 202, preventing dust from entering or escaping the PCB housing.

[0053] According to some embodiments, Figure 6 Shown Figure 2 The bottom of the central light dome 102 includes a structure for a fixed diffuser 602. The fixed diffuser 602 diffuses the light from the high-power LEDs 308 to produce more uniform illumination of the target 104. The fixed diffuser 602 has an annular upper edge 604 that seals against the lower edge of the defining ring 208 of the housing 202, and an outer edge 606 that aligns with and seals against the inner surface of the sidewall 210 of the housing 202. In some embodiments, the fixed diffuser 602 is a transparent diffuser.

[0054] According to some embodiments, Figure 7 Shown Figure 2 The bottom of the central light dome 102 includes a removable diffuser 702. The removable diffuser 702 is part of a replaceable diffuser assembly and provides a different scattering effect than the fixed diffuser 602. The annular upper edge 704 of the removable diffuser 702 abuts the lower edge of the fixed diffuser 602, while the outer edge 606 corresponds to and mates with the inner surface of the sidewall 210 of the housing 202.

[0055] According to some embodiments, Figure 8 Shown Figure 2 The bottom of the central light dome 102 includes a printed circuit board (PCB) arrangement of light sources (such as LEDs). This view fully displays all T-shaped PCBs 302 and L-shaped PCBs 304 to clearly show the layout structure of LEDs 308.

[0056] According to some embodiments, Figure 9 Shown Figure 2 Layout 900 of LEDs 308 in light dome 102. The high-power LEDs are arranged symmetrically, including four inner ring LEDs 904 in an inner ring 902, eight middle ring LEDs 908 in a middle ring 906, and sixteen outer ring LEDs 912 in an outer ring 910. To provide additional illumination coverage, four corner LEDs 916 are located at corner locations 914.

[0057] According to some embodiments, Figure 10The light dome 1002 is an arched structure comprising a housing 1004 with a mounting ring 1006 , which can be mounted with a camera 108 . The structure of the dome 1002 is similar to that of the light dome 102 .

[0058] As can be seen, the light dome 1002 has two curved edges 1008 and two straight edges 1010 on the periphery of the outer cover 1004. In some embodiments, the two curved edges 1008 may form a circular arch, but other types of arch structures may also be used. The arched structure of the light dome 1002 allows multiple light domes 1002 to be arranged in a row along their respective curved edges 1008 (see Figure 12 ). This arrangement allows for simultaneous imaging of different parts of a workpiece, or continuous image acquisition as the workpiece passes sequentially beneath each light dome. In the latter case, the array of light domes is arranged along the workpiece's path. The array of light domes can also be arranged transverse to the path to acquire cross-sectional image strips of large workpieces or images of smaller workpieces moving in parallel.

[0059] In addition, multiple light domes 1002 can be arranged adjacently by straight edges 1010 to form a light dome matrix. This matrix layout is suitable for imaging inspection of large workpieces, such as LED / LCD flat screens of televisions or monitors.

[0060] The outer cover 1004 includes sidewalls 1012 with lower edges 1014. As shown, the sidewalls 1012 are positioned on both sides of the outer cover 1004 to block light from outside the light dome 1002 from entering the dome 1002 while also reducing the impact of light leakage from within the light dome on the lighting conditions of adjacent light domes. In some embodiments, the sidewalls 1012 at the ends of the light dome row may extend downward to suppress the impact of ambient light. When the light source within the light dome 1002 is activated, the sidewalls 1012 can also suppress or reduce light leakage.

[0061] Figure 11 According to some embodiments Figure 10 A bottom perspective view of the housing 1004 of the light dome 1002 is shown. Figure 11 Visible are the straight edge 1010 , the curved edge 1008 , the side wall 1012 , and the bottom edge 1014 of the side wall 1012 .

[0062] The internal and external structures of dome 1002 are similar to those of dome 102 described above, with appropriate adjustments. Figure 10 and Figure 11 Not all features of dome 1002 are shown, such as cable exits.

[0063] Figure 12 According to some embodiments Figure 10A top view of a row of light domes 1002 is shown. Each light dome 1002 has a camera and illumination field of view 1202. As shown, the configuration of the sidewalls 1012 and bottom edge 1014, as well as the arrangement of the light sources within the light domes 1002, creates a small overlap 1204 between adjacent light domes 1002. This overlap 1204 ensures that all areas of the inspected part are covered. However, the field of view 1202 of the camera 108 is not limited by the design of the light dome 1002, but rather by the camera lens. Therefore, a larger field of view can be achieved by replacing the camera or lens, if necessary, but this may result in poorer illumination quality.

[0064] Figure 12 The overlap shown achieves coverage in the X direction. When using an array of light domes 1002 to inspect large parts, the parts can be moved relative to the light domes 1002 in the Y direction to compensate for the lack of overlap in the Y direction.

[0065] Figure 13 A perspective view of a light dome 1300 is shown, according to some embodiments. Light dome 1300 includes a housing 1302 and a casing 1306 for mounting housing 1302. Casing 1306 includes a mounting ring 1304 to which camera 108 can be mounted. As previously described, mounting ring 1304 surrounds an opening in light dome 1300, allowing camera 108 to view target 104 through the opening.

[0066] The light dome 1300 is further provided with a cable outlet 1308 for the cable 110 to pass through to supply power to the light sources in the light dome 1300 .

[0067] In some embodiments, each of the four lower sidewalls of light dome 1300 has a bottom edge, and each bottom edge has a notch 1310 to allow all or part of object 104 (e.g., when placed on a conveyor belt) to pass through. Notch 1310 allows light dome 1300 to be mounted closer to object 104 while enhancing ambient light shielding.

[0068] Figure 14 According to some embodiments Figure 13 A partially exploded perspective view of the light dome 1300 is shown. Figure 14 In the figure, outer cover 1302 has been removed to reveal inner cover 1402. Inner cover 1402 has multiple PCB connector mounting locations 1404 for securing connectors to a PCB (not shown) containing LEDs. The PCB is mounted on the underside of inner cover 1402 and exits the inner cover through PCB holes 1406 adjacent to PCB connector mounting locations 1404. Power cable 110 is routed from the PCB terminals through cable outlet 1308 and out of light dome 1300.

[0069] Figure 15 According to some embodiments Figure 13A perspective view of the housing 1306 of the light dome 1300 is shown. As previously described, the housing 1306 includes four sidewalls 1312, a mounting ring 1304, and a cable outlet 1308. Also shown is a light-transmitting base plate 1502, through which LEDs mounted on a PCB on the underside of the inner housing 1402 can illuminate the target 104 under the control of the controller 106.

Claims

1. A feature detection lighting system comprising: an outer cover having a first end provided with a mounting structure and a second end provided with a peripheral contour, the outer cover including an inner surface located between the first end and the second end; as well as A plurality of light sources are arranged on the inner surface of the outer cover; and a cutout is provided in the outer contour of the outer cover for all or part of the object to be detected to pass through.

2. The feature detection lighting system according to claim 1, wherein: The plurality of light sources includes at least ten independently addressable light sources.

3. The feature detection lighting system according to claim 1, wherein: The plurality of light sources are connected to the outer cover via flexible substrates, and each flexible substrate is integrated with a plurality of light sources.

4. The feature detection lighting system according to claim 3, wherein: The flexible substrate is mounted on a raised surface on the inner surface of the housing.

5. The feature detection lighting system according to claim 4, characterized in that: Each of the flexible substrates is provided with a connector for electrically connecting the plurality of light sources to a power source.

6. The feature detection lighting system according to claim 5, characterized in that: The invention further includes a cable connecting the connector and the power supply, wherein the cable is arranged behind the flexible substrate between the raised surfaces.

7. The feature detection lighting system according to claim 1, wherein: The invention further comprises an inner cover provided to the outer cover, wherein the inner cover is provided with light-transmitting holes corresponding to the positions of the plurality of light sources.

8. The feature detection lighting system according to claim 7, wherein: The invention further includes a fixed diffuser disposed on the outer cover.

9. The feature detection lighting system according to claim 8, wherein: Further included is a detachable diffuser disposed on the housing.

10. The feature detection lighting system according to claim 1, wherein: Further included is a fixed diffuser disposed to the housing.

11. The feature detection lighting system according to claim 10, wherein: Further included is a removable diffuser attached to the housing.

12. The feature detection lighting system according to claim 1, wherein: The outer contour of the outer cover is generally rectangular and has four corner areas; the multiple light sources are arranged in a plurality of rings between the mounting structure and the outer contour, and an additional light source is added to each corner area.

13. A feature detection lighting system comprising: an outer cover having a mounting structure at a first end and an outer contour at a second end, the outer cover including an inner surface between the first end and the second end, the inner surface having a raised surface; a plurality of light sources disposed on a raised surface on the inner surface of the housing; as well as A cable for supplying power to the plurality of light sources is arranged between the raised surfaces of the housing.

14. The feature detection lighting system according to claim 13, wherein: The plurality of light sources includes at least ten independently addressable light sources. 15 . The feature detection lighting system according to claim 13 , wherein the plurality of light sources are disposed on the raised surface via flexible substrates, and the cables are arranged between the flexible substrates below the raised surface of the housing.

16. The feature detection lighting system according to claim 13, wherein: The outer contour of the outer cover is generally rectangular and has four corner areas; the multiple light sources are arranged in a plurality of rings between the mounting structure and the outer contour, and an additional light source is added to each corner area.

17. The feature detection lighting system according to claim 13, wherein: The invention further comprises an inner cover arranged to the outer cover, wherein the inner cover is provided with light-transmitting holes corresponding to the positions of the plurality of light sources.

18. The feature detection lighting system according to claim 13, wherein: The invention further includes a fixed diffuser disposed on the outer cover.

19. The feature detection lighting system according to claim 18, wherein: Further included is a removable diffuser attached to the housing.

20. The feature detection lighting system according to claim 13, wherein: A cutout is provided in the outer contour of the outer cover for all or part of the object to be detected to pass through.

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