Optical detection device and laser processing detection method

Abstract

The application provides an optical detection device and a laser processing detection method. The optical detection device comprises a shell, a light splitting light path, a first photoelectric sensor and a first light barrier. The shell has a light passing hole for receiving radiant light of an external detection area through the light passing hole. The radiant light from the light passing hole is processed by the built-in light splitting light path and the first photoelectric sensor. The light splitting light path has a first focusing mirror. The light splitting light path is used for receiving the radiant light from the external detection area entering the shell through the light passing hole, and the radiant light is converged to the photosensitive surface of the first photoelectric sensor by the first focusing mirror. The first photoelectric sensor receives the first waveband light signal from the light splitting light path. The first light barrier is arranged between the first photoelectric sensor and the first focusing mirror of the light splitting light path, and the position of the first light barrier is on the approximate focal plane of the first focusing mirror. The first waveband light signal reaches the photosensitive surface of the first photoelectric sensor after passing through the first light barrier. The radiant light of the processing area can be accurately selected, and the influence of the light path vignetting on the radiant light intensity of the photosensitive surface of the photoelectric sensor is reduced.

Description

Technical Field

[0001] This invention relates to the field of optical inspection, specifically to an optical inspection device and a laser processing inspection method. Background Technology

[0002] Laser processing is a process of light interacting with materials. It primarily utilizes a laser beam emitted from a laser, transmitted through optical fibers and lenses, and focused onto the material surface. The material absorbs the laser energy, causing it to melt or even vaporize, thus achieving the processing objective. Due to the thermal effect of the laser, a molten pool forms in the processing area of ​​the material, radiating multiple signals, including plasma, metal vapor, optical radiation, and acoustic radiation. Numerous studies have shown that these signals are closely related to the quality of laser processing. If defects such as humps, incomplete penetration, spatter, or contamination occur during laser processing, these radiation signals will exhibit different characteristics.

[0003] Although various methods and equipment exist for detecting the quality of laser processing, the intense melting or vaporization of materials during laser processing generates light radiation. Therefore, collecting the radiation light signals during laser processing as the raw detection signal has broader applicability. By collecting data on the radiation light signals during laser processing, and after decomposing, converting, and processing the signals, characterizing data reflecting the quality of the laser processing can be obtained. This data, after being processed by a discrimination system, allows for real-time detection of the laser processing quality.

[0004] For example, Chinese Patent CN112461860A discloses a method, apparatus, and system for detecting the quality of laser-processed parts. One scheme involves receiving infrared radiation signals with wavelengths in the range of 1250nm to 1700nm using an infrared radiation signal sensor; receiving visible light radiation signals in the range of 400nm to 700nm using a visible light radiation signal sensor; and receiving laser processing reflection signals using a laser processing reflection signal sensor. Another example is a method and system for adjusting detection parameters in a laser processing process disclosed in Chinese Patent CN112894126A. This method involves pre-setting a correspondence between the types of defects in the laser processing process and the characteristics of the detection signal parameters; loading laser processing detection data; and determining a baseline value for the characteristics of the laser processing detection signal parameters based on the correspondence and the detection data. This allows for the rapid acquisition of the baseline values ​​for the laser processing detection signal parameters. Subsequently, during real-time processing, these baseline values ​​can be used to compare the process signal data of each processed part in real-time analysis, thereby improving the quality detection process of the laser processing process. Summary of the Invention

[0005] This application provides an optical inspection device for improving the directivity of the optical inspection area, obtaining more accurate inspection results reflecting the processing quality, and improving the accuracy of the optical inspection device.

[0006] In a first aspect, the optical detection device proposed in this application includes a housing, a beam-splitting optical path, a first photoelectric sensor, and a first aperture. The housing has a light-transmitting hole for receiving radiated light from an external detection area through the light-transmitting hole, and processes the radiated light from the light-transmitting hole through the built-in beam-splitting optical path and the first photoelectric sensor. The beam-splitting optical path has a first focusing lens for receiving radiated light from the external detection area that enters the housing through the light-transmitting hole, and focusing the radiated light onto the photosensitive surface of the first photoelectric sensor through the first focusing lens. The first photoelectric sensor receives a first-band optical signal from the beam-splitting optical path. The first aperture is disposed between the first photoelectric sensor and the first focusing lens of the beam-splitting optical path, and the position of the first aperture is approximately on the focal plane of the first focusing lens, so that the first-band optical signal reaches the photosensitive surface of the first photoelectric sensor after passing through the first aperture.

[0007] Therefore, in this embodiment of the application, by setting a focusing lens on the external radiation beam splitter path and setting an aperture near the focal plane of the focusing lens, the radiation light entering the limited processing area of ​​the rear photoelectric sensor through the aperture is selected by limiting the aperture. This allows for precise selection of the radiation light in the processing area and reduces the impact of the vignetting effect on the radiation intensity of the photosensitive surface of the photoelectric sensor.

[0008] In one possible implementation, the optical detection device provided in this application has a first aperture position located at the focal plane of the first focusing lens; the first photoelectric sensor is an infrared photoelectric sensor, used to receive the first band light signal as the infrared band light radiation signal of the processing point during laser processing.

[0009] Therefore, in the embodiments of this application, during laser processing inspection, since the temperature at the center of the keyhole is much higher than the temperature around the molten pool, by setting an aperture on the focal plane of the focusing lens, the influence of the infrared light radiated from the center of the keyhole on the infrared light of the area of ​​interest around the molten pool during inspection is also reduced.

[0010] In one possible implementation, the optical detection device provided in this application further includes a second photoelectric sensor and a second aperture; the beam-splitting optical path also has a second focusing lens, which is used to separate the radiated light into at least two different frequency bands. The first band optical signal is output to the first photoelectric sensor through the first focusing lens, and the second band optical signal is output to the second photoelectric sensor through the second focusing lens; the first band optical signal and the second band optical signal are different; the second aperture is disposed between the second photoelectric sensor and the second focusing lens, and the position of the second aperture is on or near the focal plane of the second focusing lens; so that the second band optical signal reaches the photosensitive surface of the second photoelectric sensor after passing through the second aperture.

[0011] Therefore, in the embodiments of this application, when the same external laser processing point is detected simultaneously by multiple photoelectric sensors, different apertures are used in the beam splitting optical path to select the same or different optical signal bands to observe the same or different laser processing areas, thereby enriching the optical inspection methods and increasing the applicability of the optical inspection equipment.

[0012] In one possible implementation, in the optical detection device provided in this application, the second aperture is located at the focal plane of the second focusing lens; and the light-passing aperture of the first aperture is different from that of the second aperture.

[0013] In one possible implementation, the optical detection device provided in this application has a first aperture and / or a second aperture as a central light-blocking aperture, which filters out the radiation light in a certain area in the middle of the aperture.

[0014] Therefore, in the embodiments of this application, the internal shape of the aperture can be configured in different ways to meet different detection requirements.

[0015] In one possible implementation, the optical inspection device further includes a calibration light source disposed inside the housing, which is used to radiate calibration light into the beam splitter path and radiate it to the external inspection area through the light-transmitting hole of the housing.

[0016] Therefore, in this embodiment, by setting the calibration light source, not only is it convenient to calibrate the photosensitive areas of the internal multi-channel photoelectric sensors during alignment, reducing the inconvenience of traditional calibration methods such as disassembling internal optical components or repeatedly calibrating the internal optical path when the equipment is used at the customer's site, thus improving the user experience, but it also allows for the use of an aperture to assist in the positioning of the photoelectric sensors during internal optical path calibration. When selecting the detection area, targeted external detection is achieved, facilitating the optical path calibration alignment process and improving detection accuracy.

[0017] In one possible implementation, a focusing lens is provided at the light-transmitting aperture or outside the optical detection device. The imaging system formed by the focusing lens and the first focusing lens makes the processing point in the external detection area and the light-transmitting aperture of the first aperture form an object-image relationship. This lens is used to collimate the radiation light from the processing point in the external detection area into parallel light. After the parallel light is transmitted to the first focusing lens through the beam-splitting optical path, it is focused onto the central light-blocking aperture by the first focusing lens. The beam-splitting optical path is also used to radiate the calibration light radiated by the calibration light source to the light-transmitting aperture, so that the calibration light at the light-transmitting aperture and the external radiation light are coaxial on the optical axis of the light-transmitting aperture.

[0018] In one possible implementation, the beam splitting optical path includes multiple beam splitters arranged in parallel segments along the optical axis of the light-transmitting aperture and set at a certain angle to the optical axis; each beam splitter is used to split the radiation light from the outside world on the optical axis of the light-transmitting aperture to the corresponding photoelectric sensor; one or more of the following are provided between each beam splitter and the corresponding photoelectric sensor: a filter, a neutral density filter, and a focusing lens.

[0019] In one possible implementation, the calibration light source is positioned at the end of the last beam splitter, away from the light-transmitting aperture, so that the calibration light is sequentially transmitted through multiple beam splitters arranged in parallel and then focused onto the external detection area by a focusing lens.

[0020] In one possible implementation, the calibration light source is separately positioned in one of the multiple beam splitters in the beam splitting optical path, and the calibration light radiated by the calibration light source is radiated to the light-transmitting aperture separately, so that the calibration light at the light-transmitting aperture and the external radiation light are coaxial on the optical axis of the light-transmitting aperture.

[0021] In one possible implementation, the housing includes an integrated bottom shell and a cover plate fixed to the top of the bottom shell; the bottom shell has an integrated base surface and multiple outer side walls surrounding the periphery of the bottom surface, the base surface and the multiple outer side walls forming an internal cavity; a light-transmitting hole is opened on one of the outer side walls, through which radiation light from an external detection area is received; the base surface of the bottom shell extends upward to form a mounting base integrally formed with the bottom shell; the mounting base includes one or more of a beam splitter mounting base, a condenser mounting base, a neutral density filter mounting base, a filter mounting base, and a calibration light source mounting base; the mounting base is used to embed or fix a corresponding beam splitting optical path, a first photoelectric sensor, a second photoelectric sensor, and a calibration light source; wherein, the beam splitting optical path includes one or more of a beam splitter, a condenser, a neutral density filter, and a filter.

[0022] Secondly, this application proposes a laser processing inspection method, applied in optical inspection equipment, the inspection method including the following steps:

[0023] The optical radiation signal at least one processing point in the laser processing path is received by a photoelectric sensor. The optical radiation signal includes one or more of the following: infrared radiation signal, visible light radiation signal, and processing laser reflection signal.

[0024] The radiation light region of the processing point determined by the photoelectric sensor is determined by a first aperture set between the photoelectric sensor and the focusing lens of the beam splitter; wherein the position of the first aperture is approximately on the focal plane of the first focusing lens.

[0025] Based on the shape of the aperture of the first aperture, determine whether the photoelectric sensor receives the central radiation light or the edge radiation light of the keyhole at the laser processing point.

[0026] Therefore, in this embodiment, by setting a focusing lens on the external radiation beam splitter path and setting an aperture near the focal plane of the focusing lens, the radiation light entering the limited processing area of ​​the rear photoelectric sensor through the aperture is selected by limiting the aperture. This allows for precise selection of the radiation light in the processing area and reduces the impact of the vignetting effect on the intensity of the radiation light on the photosensitive surface of the photoelectric sensor.

[0027] In one possible implementation, the first aperture is a central light-blocking aperture, which filters out the radiation light from the center of the keyhole of the laser processing point. Attached Figure Description

[0028] Figure 1 This is a schematic diagram of the optical path of an optical detection device according to an embodiment of this application;

[0029] Figure 2 This is a schematic diagram of the optical path of another optical detection device according to an embodiment of this application;

[0030] Figure 3 This is a schematic diagram of the aperture structure in an optical detection device according to an embodiment of this application;

[0031] Figure 4 This is a schematic diagram of the optical path of another optical detection device according to an embodiment of this application;

[0032] Figure 5 This is a schematic diagram of the optical path of another optical detection device according to an embodiment of this application;

[0033] Figure 6 This is a schematic diagram of a shell cover structure according to an embodiment of this application;

[0034] Figure 7 This is a schematic diagram of the bottom shell structure of an optical detection device according to an embodiment of this application;

[0035] Figure 8 This is a flowchart of an optical path calibration method according to an embodiment of this application; and

[0036] Figure 9 This is a flowchart of a laser processing inspection method according to an embodiment of this application. Detailed Implementation

[0037] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0038] The terminology used in the embodiments of this application is for the purpose of describing specific embodiments only and is not intended to limit the invention. The singular forms "a," "the," and "the" used in the embodiments, descriptions, and claims of this application are also intended to include the plural forms unless the context clearly indicates otherwise. It should be understood that the term "and / or" used herein is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A alone, A and B simultaneously, and B alone. Additionally, the character " / " in this document generally indicates that the preceding and following related objects are in an "or" relationship. It should be understood that although the terms "first," "second," and similar words may be used in the embodiments of this application, they do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Similarly, "a" or "one," and similar words do not indicate a quantity limitation, but rather indicate the existence of at least one. "A plurality" in the embodiments of this application refers to two or more. The optical lens involved in this application can be an optical lens group. For example, a focusing lens can be understood as a focusing lens group with focusing function formed by one or more lenses through multi-lens arrangement, bonding, etc. A beam splitter can be understood as a lens group consisting of one or more lenses that achieve the effect of beam splitting through beam splitting, refraction, reflection, and transmission.

[0039] When laser processing is performed on a workpiece surface using a laser processing head, one or more optical paths are typically split within the laser processing optical path for an optical inspection system to monitor the laser processing process and perform various photoelectric conversions of the radiation light signals collected during the monitoring process. Since the laser processing system involves collimating optical paths, focusing optical paths, and even galvanometer oscillation optical paths, and because the optical inspection system may require multiple photoelectric sensors to detect the processing, a relevant solution involves dividing the radiation light from the laser processing area into specific wavelength bands and outputting them to corresponding photoelectric sensors. These sensors then detect changes in the intensity of the light signals in each wavelength band to analyze and determine the quality of the laser processing.

[0040] In the traditional laser processing inspection process, a calibration scheme is used to calibrate and align the radiation light paths corresponding to multiple photoelectric sensors before the optical inspection equipment leaves the factory. When used at the customer's site, the radiation light paths corresponding to the multiple sensors are further aligned with the laser processing light path (the optical axes of the corresponding light paths are consistent or parallel), and then the photosensitive surface of the photoelectric sensor is aligned with the laser processing point in the laser processing area.

[0041] During production and R&D, the applicant discovered that the traditional method of using photoelectric sensors with their photosensitive surfaces aligned with the laser processing area to monitor the quality of the laser processing points still fails to clearly reflect some laser processing defects. For example, in laser welding, some welding defects are more correlated with the light radiation signal outside the center of the laser processing keyhole. If the photoelectric sensor is used to monitor the corresponding laser processing keyhole, the strong light signal at the center of the keyhole will mask the useful light signal in the region of interest. Therefore, it is necessary to shield against strong signal interference from the center of the laser processing point or other areas to improve the signal-to-noise ratio of the corresponding defect signal.

[0042] For this purpose, please refer to Figure 1 This application provides an optical detection device 100, including: a housing 110, a beam-splitting optical path 120, a first photoelectric sensor 130, and a first aperture 330. The housing 110 has a light-transmitting aperture 112 for receiving radiation light from an external detection area. It is understood that a focusing lens can be provided on the light-transmitting aperture 112 to collimate the external radiation light into parallel light. Alternatively, the collimated parallel light from the outside can be directly received through the light-transmitting aperture 112. The housing 110 processes the radiation light from the light-transmitting aperture 112 through the built-in beam-splitting optical path 120 and the first photoelectric sensor 130. The beam-splitting optical path 120 has a first focusing lens 122, which receives the radiation light from the external detection area 190 entering the housing 110 through the light-transmitting aperture 112, and focuses the radiation light onto the photosensitive surface of the first photoelectric sensor 130 through the first focusing lens 122. The first photoelectric sensor 130 is used to receive a first-band optical signal from the beam-splitting optical path 120. A first aperture 330 is disposed between the first photoelectric sensor 130 and the first focusing lens 122 of the beam-splitting optical path 120, and the position of the first aperture 330 is approximately on the focal plane of the first focusing lens 122, preferably on the focal plane, so that the first-band optical signal reaches the photosensitive surface of the first photoelectric sensor 130 after passing through the first aperture 330.

[0043] In this embodiment of the application, in the optical inspection equipment, a focusing lens is set on the external radiation beam splitter path, and an aperture is set near the focal plane of the focusing lens. The aperture diameter is then used to select the radiation light entering the defined processing area of ​​the subsequent photoelectric sensor, thereby accurately selecting the radiation light in the processing area and reducing the influence of optical path vignetting effect on the radiation light intensity of the photosensitive surface of the photoelectric sensor. Specifically, the first photoelectric sensor is an infrared photoelectric sensor. When detecting the infrared radiation signal of the molten pool, the first band of light signal received is the infrared radiation signal of the processing point during laser processing. During laser processing inspection, since the temperature at the center of the keyhole is much higher than the temperature around the molten pool, setting an aperture on the focal plane of the focusing lens also reduces the influence of the infrared light radiated from the center of the keyhole on the infrared light in the detection area of ​​interest around the molten pool.

[0044] When optical inspection equipment meets the requirements for multi-path optical inspection, the applicant finds that in some applications, different optical paths have different requirements for shading the inspection area. Please refer to [further details]. Figure 2 The optical detection device provided in this application embodiment further includes a second photoelectric sensor 132 and a second aperture 332. The second photoelectric sensor 132 is used to receive a second-band optical signal from the beam-splitting optical path 120. The beam-splitting optical path 120 also has a second focusing lens 121. The beam-splitting optical path 120 is used to separate the radiated light into at least two different frequency bands of radiated light. The first-band optical signal is output to the first photoelectric sensor 130 through the first focusing lens 122, and the second-band optical signal is output to the second photoelectric sensor 132 through the second focusing lens 121. The first-band optical signal and the second-band optical signal are different. The second aperture 332 is disposed between the second photoelectric sensor 132 and the second focusing lens 121, and the position of the second aperture 332 is on or near the focal plane of the second focusing lens 132, so that the second-band optical signal reaches the photosensitive surface of the second photoelectric sensor 132 after passing through the second aperture 332.

[0045] In this embodiment of the application, when the same external laser processing point is detected simultaneously by multiple photoelectric sensors in the optical inspection equipment, different apertures are used through the beam splitter 120 to select the same or different light signal bands to observe the same or different laser processing areas, thereby enriching the optical inspection methods and increasing the applicability of the optical inspection equipment.

[0046] Furthermore, the second aperture 332 is located at the focal plane of the second focusing lens; and the light-passing apertures of the first aperture 220 and the second aperture 332 are different. Therefore, when the first and second band optical signals are the same, for example, both are infrared radiation signals, the first aperture 330 uses a center-blocking scheme to collect the light radiation signal around the laser processing keyhole; the second aperture 332 uses a small aperture in the center to collect the light radiation signal at the center of the laser processing keyhole. This allows for precise independent detection and signal quality assessment of different regions. Similarly, when the first and second band optical signals are different, with the first band being an infrared radiation signal and the second band being a visible light radiation signal, the first aperture 330 collects the infrared region of interest signal, and the second aperture 332 collects the visible light region of interest signal, thus meeting the laser processing detection requirements in another application scenario.

[0047] The second aperture 332 is located at the focal plane of the second focusing lens 121; and the light-passing apertures of the first aperture 330 and the second aperture 332 are different. At this time, as... Figure 3 As shown, the first aperture 330 is configured as a center-blocking aperture, and the second aperture 332 is configured as a center-through-light-blocking aperture with edge-blocking light. It can be understood that the internal shape of the aperture can be configured in different ways to meet different detection needs. For example, in a center-blocking aperture, the center blocking plate can be elliptical, rectangular, irregularly shaped, or have multiple blocking holes. The edge of the edge-blocking aperture can be serrated. A combination of center-blocking and edge-blocking apertures can be used simultaneously. Therefore, it can be understood that when the first aperture 330 and / or the second aperture 332 are center-blocking apertures, the radiation light in a certain area in the center of the aperture is filtered out by the center-blocking aperture. The actual deformable shapes of the first aperture 330 and / or the second aperture 332 are not described in detail in this embodiment.

[0048] Please participate Figure 4 The optical inspection device provided in this application embodiment also includes a calibration light source 134 disposed inside the housing 110. The calibration light source 134 is used to radiate calibration light into the beam splitter 120 and radiate it to the external detection area 190 through the light-transmitting hole 112 of the housing 110. In this application embodiment, by embedding a calibration light source inside the optical inspection device, it is convenient to calibrate the photosensitive areas of the internal multi-channel photoelectric sensors during alignment. This reduces the inconvenience of needing to disassemble internal optical components for traditional calibration or repeatedly calibrate the internal optical path when the device is used in the customer's field, thus improving the user experience. By setting an internal aperture, the photoelectric sensor is positioned by the aperture during internal optical path calibration. When selecting the detection area, targeted external detection is achieved, which facilitates the optical path calibration and alignment process and improves detection accuracy.

[0049] It is understood that the optical inspection device provided in this application embodiment may have a focusing lens 124 installed at the light-transmitting hole 112 of the housing 110 or outside the optical inspection device. The focusing lens 124, together with the first focusing lens 122 and / or the second focusing lens 121, forms an imaging system that makes the processing point of the external inspection area and the light-transmitting holes of the first aperture 330 and / or the second aperture 332 form an object-image relationship. This system is used to collimate the radiation light from the processing point of the external inspection area into parallel light, and after the parallel light is transmitted to the first focusing lens 122 and / or the second focusing lens 121 through the beam-splitting optical path 120, it is focused onto the central light-blocking aperture by the first focusing lens 122 and / or the second focusing lens 121. The beam-splitting optical path 120 is also used to radiate the calibration light radiated by the calibration light source 134 to the light-transmitting hole 112, so that the calibration light at the light-transmitting hole 112 and the external radiation light are coaxial on the optical axis of the light-transmitting hole. It is understood that coaxiality here can mean that the optical paths are the same or parallel.

[0050] In this embodiment, during internal debugging before production, the calibration light source 134 serves as the reference for aligning various optical paths. Multiple photodiodes (such as the first photoelectric sensor 130 and the second photoelectric sensor 132) can emit light through the beam-splitting optical path 120 with their centers perpendicular to the calibration light source 134. The beam-splitting optical path 120 directs the calibration light radiated by the calibration light source 134 to the light-transmitting aperture, ensuring that the calibration light at the light-transmitting aperture 112 is coaxial with the external radiated light on the optical axis of the light-transmitting aperture 112. The optical inspection device 100 is integrated onto the external laser processing head 1 (participating in...). Figure 5 When aligning the optical inspection equipment 100 with the processing light of the external laser processing equipment, the light emitted from the calibration light source 134 is used as the alignment reference line, so that the processing laser and the light emitted from the calibration light source 134 through the through hole of the housing 110 coincide. This ensures that the light signal radiation area of ​​the laser processing coincides with the photosensitive area (which can be the photosensitive surface of the photodiode) inside the optical inspection equipment 100, and also ensures the convenience of production, assembly and debugging of the optical inspection equipment 100, thus improving the efficiency of optical path alignment.

[0051] Furthermore, in this embodiment, the beam-splitting optical path 120 is composed of multiple focusing lenses (121, 122, 123, 124) and multiple beam-splitters (125, 126, 127). It can be understood that the focusing lenses can be composed of one or more optical lenses to achieve focusing or collimation of the optical path. The beam-splitters can be coated lenses that split optical signals for different optical bands, and can separate selected optical signals from the main optical path through coatings with different transmittance-to-reflection ratios.

[0052] In one laser processing application scenario, it is necessary to selectively monitor the radiation light from the laser-processed surface in segments. For example, it is necessary to observe the changes in infrared radiation signals, visible light radiation signals, and laser processing reflection signals from the laser processing light signal radiation region to determine the quality of the laser processing. The infrared radiation signal corresponds to the infrared radiation signal with wavelengths in the range of 1250nm to 1700nm. The visible light radiation signal corresponds to the visible light radiation signal in the range of 400nm to 700nm. The laser processing reflection signal corresponds to the laser reflection signal during actual laser processing, such as processing laser wavelengths of 915nm, 1064nm, and 1080nm. The wavelength of the processing laser is related to the wavelength of the actual laser used. In some operating environments, the suitable range for the infrared radiation signal can extend beyond the 1250nm to 1700nm range. In some operating environments, the visible light radiation signal can extend beyond the 400nm to 700nm range. Correspondingly, the optical detection device 100, in addition to the first photoelectric sensor 130 and the second photoelectric sensor 132, also includes a third photoelectric sensor (not shown in the figure). For example, the first photoelectric sensor is an infrared photodiode used to sense infrared radiation light signals; the second photoelectric sensor 132 is a visible light photodiode used to sense visible light radiation signals; the photodiode corresponding to the third photoelectric sensor is used to sense laser reflection signals. They are stacked sequentially above the second photoelectric sensor 132 or placed between the first photoelectric sensor 130 and the second photoelectric sensor 132, and the intensity of the processing laser signal is sensed by reflecting the light from the processing area back into the detection device through the beam splitter (not shown) of the beam splitter 120.

[0053] It is understood that in the above application scenario, the beam-splitting optical path 120 is disposed at the light entrance aperture of the optical detection device 100. The beam-splitting optical path 120 includes: a focusing lens 124 for collimating the coaxial radiation light in the external detection area, and multiple beam splitters (125, 126, 127) stacked sequentially along the axis of the coaxial radiation light. The parallel light passing through the focusing lens 124 is split into an infrared radiation signal by the beam splitter 126 and sent to the first photoelectric sensor 130 (which may be an infrared photodiode). Other light outside the infrared radiation signal frequency band passes through the beam splitter 126 and is then split into a visible light radiation signal by the beam splitter 125 and sent to the second photoelectric sensor 132 (which may be a visible light photodiode). It is understood that in this embodiment, a third photoelectric sensor (which may be a laser sensor, not shown) and a beam splitter (not shown) may exist. Furthermore, after the infrared radiation signal and other light outside the visible light frequency band pass through the beam splitter 125, the laser reflection signal is further split into the third photoelectric sensor by the continuously stacked beam splitters (not shown). It is understood that in some special applications, photoelectric sensors of other frequency bands and corresponding beam splitters can be superimposed on the optical inspection device 100. To calibrate the multiple beams split by the beam splitter, the beam splitting optical path 120 also includes a focusing lens 123 for collecting the calibration light. The focusing lens 123 collimates the calibration light emitted from the calibration light source 134 and guides it into the coaxial radiation light, so that the calibration light coincides with the reflected light from the optical signal radiation area of ​​the processed surface in the beam splitting optical path 120. It is understood that in some application scenarios, since the optical inspection device 100 is installed on one side of the laser processing head, it indirectly obtains external radiation light by acquiring the incoming light from the laser processing head. In this case, the focusing lens 123 can be a field lens set on one side of the laser head, and the focusing lens 123 may not be included on the optical inspection device 100 itself. Furthermore, this application can be implemented by setting a focusing lens on the light-transmitting aperture 112, or by using a focusing lens outside the monitoring device, or by using a focusing lens set on the beam splitting optical path 120 inside the light-transmitting aperture 112 to collect external radiation light. Furthermore, by setting the focusing lens in different positions for different application scenarios, the calibration of multi-optical path detection equipment can be flexibly realized, thereby ensuring that the calibration light, processing laser, and external radiation light to be detected are consistent on the light-passing aperture, the main axis of the beam splitting path, or the optical axis of the processing laser output in the multi-optical path detection scheme.

[0054] Please see Figure 5This is a schematic diagram of another optical path structure of the optical detection device 100 according to an embodiment of the present invention. In this embodiment, the calibration light source 134 is placed at the end of the beam splitting optical path 120 and at the rear end of the beam splitters 126 and 125 in the direction of incident radiation light. That is, the beam splitting optical path 120 still receives the coaxial radiation light from the external detection area 190 through the light-passing hole 112 opened in the housing 110, so that the radiation light passes sequentially through the beam splitters 126 and 125, and then the coaxial radiation light from the external detection area is split into wavelengths, then split into the first photoelectric sensor 130 by the first aperture 330, and then split into the second photoelectric sensor 132 by the second aperture 332. The calibration light source 134 is set at the rear end of the beam splitter 125, so that the calibration light passes sequentially through the beam splitter 125 and the beam splitter 126, and then converges onto the external detection area 190 by the focusing lens 124.

[0055] As can be seen, the beam-splitting optical path 120 includes multiple beam splitters (125, 126) arranged in parallel segments along the optical axis of the light-passing aperture 112 and set at a certain angle to the optical axis. Each beam splitter is used to split the external radiation light from the light-passing aperture 112 onto the corresponding photoelectric sensor. One or more of a filter, neutral density filter, and focusing lens are provided between each beam splitter and the corresponding photoelectric sensor. If the beam splitter can filter the light signal of a specific wavelength band to the corresponding photoelectric sensor through coating, the filter can be omitted. However, to increase the beam splitting accuracy, the filter can be added repeatedly. In one case, the filter can integrate an optical isolation effect to reduce the intensity of the radiation light, thereby adapting to the sensing range of the photoelectric sensor. In this case, the neutral density filter can also be omitted. In another case, the parallel light or astigmatic light from the beam splitter can be directly transmitted to the photoelectric sensor, thus the focusing lens can also be omitted.

[0056] It is understood that in this embodiment, the calibration light source 134 can also be individually positioned as one of the multiple beam splitters in the beam splitting optical path, allowing the calibration light radiated by the calibration light source 134 to be radiated separately onto the light passage 112, so that the calibration light at the light passage 112 is coaxial with the external radiated light on the optical axis of the light passage 112. Furthermore, in this embodiment, the calibration light can be guided into the optical path system without losing too much energy in the main optical path by specifically coating the corresponding beam splitter, taking into account the wavelength characteristics of the calibration light source 134.

[0057] In this embodiment, a filter 128 is added between the beam splitter 126 and the first photoelectric sensor 130 in the beam splitter path 120 to more effectively filter out optical signals for the photosensitive wavelength band of the first photoelectric sensor 130. A filter 129 is added between the beam splitter 125 and the second photoelectric sensor 132 in the beam splitter path 120 to more effectively filter out optical signals for the photosensitive wavelength band of the second photoelectric sensor 132. It can be understood that the beam splitter path can also employ a similar design, adding filters between the corresponding beam splitter and photoelectric sensor to more accurately filter out optical signals for specific wavelength bands. To adjust the absorption degree of the photoelectric sensor for specific wavelength band optical signals, in this embodiment, one or more optical attenuators (not shown) are added before or after the filter to adjust the input / output signal intensity of the photoelectric sensor.

[0058] Furthermore, in this embodiment, the optical detection device 100 also includes a position adjustment mechanism 136. The calibration light source 134 is detachably connected to the position adjustment mechanism 136. The position adjustment mechanism 136 drives the calibration light source 134 to move in a planar or three-dimensional space, thereby aligning and installing the first photoelectric sensor 130 and the second photoelectric sensor 132 or other corresponding photoelectric sensors on the beam splitter path. It can be understood that the position adjustment mechanism 136 can also be fixedly integrated with the calibration light source 134, and then fixed on the housing 110 after aligning the multiple sensors (130, 132).

[0059] The optical inspection device 100 provided in this application embodiment can be used in an online inspection system with multiple photoelectric sensors during laser welding processing. The calibration light source 134 can be a visible light laser source, such as a laser source that is consistent with the guiding red light in most laser processing systems. On the one hand, the monochromaticity and directionality of the laser source are good, and on the other hand, the color difference caused by the difference between its wavelength and the processing laser in the laser processing system can be minimized.

[0060] In one application scenario, the optical inspection device 100 provided in this application embodiment includes a beam splitter 126, a focusing lens 122, at least one first photoelectric sensor 130, and at least one calibration light source 134. Optionally, to calibrate the position of related devices using the calibration light source 134, a CCD camera with a lens can be detachably mounted at the position of the first photoelectric sensor 130 to replace manual visual alignment during the calibration process. To improve alignment accuracy, a scale alignment plate can be introduced on the external detection area 190 of the laser-processed surface to increase the accuracy of positional movement. Furthermore, when the radiated calibration light reflected from the external detection area 190 is focused by the focusing lens 122 onto the position of the first photoelectric sensor 130, the calibration position can be determined by replacing the position of the first photoelectric sensor 130 with the CCD camera, or by the CCD camera acquiring the change in the light spot corresponding to the calibration light source on the scale alignment plate through a circulator / coupler, etc., in the beam splitter path. Optionally, the focusing lens 124 is a focusing lens or focusing lens group in the laser processing system that focuses the processing laser using a single lens or lens group.

[0061] Please refer to the following: Figure 6 and Figure 7 This is a schematic diagram of the integrated structure of the optical inspection device 100 according to an embodiment of the present invention. In this embodiment, the housing 110 of the optical inspection device 100 includes an integrated bottom shell 111 and a cover plate 114 fixed to the top of the bottom shell 111. The bottom shell 111 has an integrated base surface and multiple outer side walls surrounding the bottom surface, forming an internal cavity. A light-transmitting hole 112 is opened on one of the outer side walls, and the radiated light from the external detection area 190 is collected through the light-transmitting hole 112. In this embodiment, the calibration light source 134 is placed in the integrated bottom shell 111, so that after the calibration light source 134 has completed factory calibration, it can be firmly positioned on the bottom shell 111, reducing the inconvenience of replacing the calibration light source in subsequent factory applications and simplifying the calibration scheme in the factory application environment.

[0062] In this embodiment, the radiated light entering through the light-transmitting aperture 112 can originate from the optical path in the external laser processing head 1, specifically from the radiated light at the processing point 260 in the external detection area 190. This radiated light is collimated by the focusing lens 124 and then split into the light-transmitting aperture 112. In one application, a focusing lens 124 is also provided on the light-transmitting aperture 112 to collect the radiated light from the external detection area 190.

[0063] The base surface of the bottom shell 111 extends upward to form a mounting base integrally formed with the bottom shell. It is understood that the mounting base includes, but is not limited to, one or more of the following: a beam splitter mounting base, a condenser mounting base, a neutral density filter mounting base, a sensor circuit board mounting base, and a calibration light source mounting base. Various mounting bases can be one or more of the following: a U-shaped groove structure, multiple column limiting structures, or other mechanical locking mechanisms. The mounting base is used to embed or fix the beam splitter path 120, the first photoelectric sensor 130, the second photoelectric sensor 132, the third photoelectric sensor 131, and the calibration light source 134 inside the optical detection equipment 100. Furthermore, the beam splitter path 120 receives the radiated light from the external detection area 190 through the light-transmitting hole 112 opened in the housing 110. The beam splitter path 120 includes one or more of a beam splitter, a condenser, a neutral density filter, and a filter. The first photoelectric sensor 130 is used to receive the first band optical signal from the beam splitter path 120 passing through the first aperture 330. The second photoelectric sensor 132 is used to receive the second-band optical signal from the beam-splitting optical path 120. The third photoelectric sensor 131 is used to receive the third-band optical signal from the beam-splitting optical path 120. The calibration light source 134 is used to radiate calibration light into the beam-splitting optical path 120 and radiate it to the external detection area through the light-transmitting hole 112 of the housing 110. The beam-splitting optical path 120 ensures that the calibration light from the calibration light source 134 and the radiated light from the external detection area are coaxial on the axis of the light-transmitting hole of the housing 110. The first-band, second-band, and third-band optical signals are different. The first-band optical signal is an infrared radiation signal corresponding to a wavelength in the range of 1250nm to 1700nm. The second-band optical signal is a visible light radiation signal corresponding to the range of 400nm to 700nm. The third-band optical signal is a laser processing reflection signal from the outside. The difference between the first-band and second-band optical signals can be due to completely different wavelengths of the two optical signals, or partial overlap of wavelengths in the two optical signals.

[0064] In this embodiment, optionally, the housing 110 may be sequentially provided with a condenser lens mounting base, a beam splitter mounting base, a neutral density filter mounting base, and a filter mounting base along the optical path direction. It is understood that in some applications, the order of the mounting bases may be different. For example, the condenser lens mounting base, beam splitter mounting base, filter mounting base, and neutral density filter mounting base may be sequentially provided along the optical path direction. In some structural configurations, if the radiation light from the outside is collimated parallel light, then the condenser lens mounting base can be omitted. In some structural configurations, some mounting bases can perform multiple functions; for example, the filter mounting base and the neutral density filter mounting base can be combined into one unit that simultaneously accommodates both a filter and a neutral density filter. To better embed related lenses, photoelectric sensors, circuit boards, or other internal devices into the mounting base, reference can be made to the lens mount and optical module disclosed in Chinese Patent Application No. CN202023067916.9. After the relevant devices are detachably clamped or fixed in the mounting via matching lens holders or other structures, customized lens holders allow for the installation of multiple different devices with the same or similar specifications within the mounting base. Furthermore, to adapt to environments with varying optical parameters of lenses or sensors, a batch of identical housings 110 can be precisely adapted to various types of devices to meet the needs of different application scenarios. This improves the accuracy requirements of multi-channel optical sensors for high-precision photoelectric signal consistency and enhances the product's practicality.

[0065] like Figure 7 As shown in the embodiment of this application, the optical detection device 100 receives radiation light from an external detection area 190 through a light-transmitting aperture 112. A plurality of parallel beam splitter mounts (227, 226, 225, 235) are embedded in a mounting base inside the housing 110 at a 45-degree angle to the optical axis. Each beam splitter mount includes beam splitters with different coatings internally. Beam splitter mount 227 is used to split the calibration light from the calibration light source 134 onto the optical axis of the light-transmitting aperture 112. Beam splitter mounts 226, 225, and 235 are used to receive the detection beam and split it into outgoing light beams of different frequency bands onto condenser mounts (222, 221, 231). Condenser lenses are installed inside the condenser mounts (222, 221, 231) to focus the outgoing light from the beam splitter mounts (226, 225, 235).

[0066] A neutral density (ND) lens is installed inside the neutral density (ND) lens mount 240, positioned between the beam splitter mount and the focusing lens mount, to reduce the light intensity of the light emitted from the beam splitter mounts (226, 225, 235). A filter mount 250 is installed inside the filter mount, positioned between the focusing lens mount and the photoelectric sensor. Different filters within the filter mount have corresponding coatings to further filter out the radiation light of corresponding wavelength bands and direct it to the corresponding photoelectric sensor. The photoelectric sensors (130, 132, 131) receive the light emitted from the corresponding filter mount 250 and output the photoelectric converted detection signal. It can be understood that the positions of the filter mount 250 and the ND lens mount 240 can be interchanged. It can be understood that, combined with... Figure 3 As shown in the cover plate 114 of the housing 110, the cover plate 114 has a groove. The filter mount 250 can be inserted into the mounting base inside the housing 110 through the groove, so that when the optical inspection equipment 100 is used at the user's site, the corresponding filter mount 250 can be replaced according to the signal requirements of the optical radiation signal band at the site, so as to filter out the optical signal of the required band.

[0067] In this embodiment, the detection beam is incident at a 45° angle from the front of the beam splitter mount 227 corresponding to the calibration light source 134. Since the calibration light source side does not need to receive external radiation, the beam splitter mount 227 transmits all the detection beam from the outside to the beam splitter mount corresponding to the subsequent photoelectric sensor. The beam splitter mount corresponding to the photoelectric sensor can be fitted with a 5:5 beam splitter, that is, a semi-transmissive and semi-reflective beam splitter. When the beam splitter is a 5:5 beam splitter, after the beam splitter mount 226 corresponding to the first photoelectric sensor 130 receives the detection beam, half of it is reflected towards the condenser mount 240, and half is transmitted towards the beam splitter mount 225 corresponding to the second photoelectric sensor 132. Similarly, the second photoelectric sensor 132 corresponds to the beam splitter mount 225, the third photoelectric sensor 131 corresponds to the beam splitter mount 235, and the Nth photoelectric sensor corresponds to the Nth beam splitter mount.

[0068] In this embodiment, the beam splitter mounting base is a structure in which two columns clamp the beam splitter base, and each of the two columns has a insertion groove on its facing side. The beam splitter base can be directly inserted into the first insertion groove. The two columns clamp the beam splitter base, and the beam splitter base and the beam splitter mounting base fit tightly in this design, eliminating the need to fix the beam splitter base to the housing. This design is not only secure but also facilitates lens replacement and quick installation. For a better understanding of the internal structure and optoelectronic device assembly relationship of the optical inspection device 100 in this application embodiment, please refer to Chinese Patent CN202310997745.9, "An Integrated Housing for a Laser Processing Inspection Module," published by the applicant on October 13, 2023.

[0069] Combination Figures 4-7This application proposes an optical path calibration method for use in optical inspection equipment. The calibration light source 134 can be a visible light laser source. The laser beam generated by the calibration light source 134 is collimated into parallel light by a convex lens 123, and a portion of the collimated light is reflected by a beam splitter 127, then converged to the center of the external detection area 190 by a focusing lens 124. Optionally, a scale plate can be used to determine the center, ensuring that the center of the external detection area 190 (the center of the scale plate) is coaxial with the centers of the focusing lens 124, beam splitter 127, and beam splitter 126. Furthermore, the portion of the collimated light reflected by the beam splitter 127 from the laser beam emitted by the calibration light source 134 is coaxial with this center.

[0070] Please see Figure 8 The optical path calibration method provided in this application includes the following steps:

[0071] Step 510: Adjust the position of the calibration light source 134 so that the beam it generates passes through the beam splitter 120 and then through the light-transmitting aperture 112 to the center of the external detection area 190. The beam splitter 120 ensures that the calibration light from the calibration light source 134 and the radiation light from the external detection area 190 are coaxial on the axis of the light-transmitting aperture 112 of the housing 110. It can be understood that the center of the external detection area 190 can be a laser processing calibration point, or any point that is convenient for adjustment and observation; furthermore, there are no restrictions.

[0072] Step 520: Adjust the positions of the first photoelectric sensor 130 and the second photoelectric sensor 132 respectively, so that the light-incident surface of each photoelectric sensor is aligned with the center of the external detection area 190.

[0073] The optical path calibration method for the optical inspection device 100 provided in this application embodiment allows for adjustable positioning of the calibration light source 134 built into the optical inspection device. This ensures that the calibration light source 134, when emitted through the light outlet of the optical inspection device 100, is coaxial with the radiated light path. Consequently, when the optical inspection device 100 is placed on a laser processing head (not shown), the processing laser and the calibration laser can also be coaxially aligned to the same processing point. After determining the position of the calibration light source, the consistency of the internal optical path of the optical inspection device at the time of manufacture is further ensured by adjusting the positions of multiple photoelectric sensors.

[0074] Further, step 510 specifically involves: setting the calibration light source 134 on the position adjustment mechanism 136; adjusting the position adjustment mechanism 136 allows the calibration light source 134 to translate in the XY plane, or to have an angular offset in the XY direction. The position adjustment mechanism 136 adjusts the calibration light source 134 so that a portion of the collimated light generated by the laser beam, after being reflected from the center of the beam splitter 127, coincides with the center of the external detection area 190 (the center of the scale plate) and the optical axis of the focusing lens 124, and then the calibration light source 136 is fixed to the housing. It can be understood that removing the adjustment mechanism 136 to fix the calibration light source 136 to the housing, or retaining and locking the position of the adjustment mechanism 136, can also keep the calibration light source 136 relative to the main optical axis unchanged. The scale plate on the external detection area 190 is set on the focal plane of the focusing lens 124, and the convergence point of the calibration light source 134 is aligned with the center of the external detection area 190, that is, the convergence point of the calibration light source 134 coincides with the central crosshair of the scale plate. The centers of beam splitters 127 and 126 are made coaxial. The optical axes of focusing lens 122 and focusing lens 123 are aligned and placed on one side of beam splitter 127.

[0075] Further, step 520 can be as follows: A first aperture 330 is positioned near the location of the first photoelectric sensor 130, i.e., at the focal plane of the focusing lens 122. A CCD camera with a lens observes the first aperture 330 at the far end of the optical axis of the focusing lens 122, ensuring that the first aperture 330 can be clearly imaged on the camera side. According to the imaging principle, the first aperture 330 at the focal plane of the focusing lens 122 and the scale plate 260 at the focal plane of the focusing lens 124 form an object-image relationship. Therefore, the camera CCD can simultaneously and clearly image both the first aperture 330 and the scale plate 260. Observing the image on the camera CCD, the position of the first aperture 330 is adjusted by translation on the XY plane until its center coincides with the center of the crosshair of the scale plate 260. The first photoelectric sensor 130 is placed close to the first aperture 330, and its position is adjusted by translation on the XY plane until its center is aligned with the center of the first aperture 330.

[0076] Optionally, after adjusting the position of the first aperture 330 in step 520, the first aperture 330 can be retained or deleted. When removing the first aperture 330, the position of the first photoelectric sensor 130 is slightly moved along the optical axis in the direction of the first aperture 330. The slight movement can be the thickness of the first aperture 330, and the first photoelectric sensor 130 is fixed.

[0077] It is understood that the same steps described above are repeated when adjusting the positions of other photoelectric sensors such as the second photoelectric sensor 132 and the third photoelectric sensor 131. This will not be elaborated upon here.

[0078] Through the above calibration steps, the internal optical path of the optical detection device 100 is adjusted. At this time, the light emitted by the calibration light source 134 coincides with the optical axis of the optical detection device 100.

[0079] When the optical inspection equipment 100 is used in a factory processing environment, it is connected to the laser processing head via an optical path adapter module. To confirm that the calibration light source 134 of the optical inspection equipment 100 coincides with the optical axis of the guiding red light or processing laser of the laser processing head, the defocusing amount of the worktable of the laser processing equipment can be changed. Under different defocusing amounts, the refraction angle of the lens in the optical path adapter module can be adjusted so that the light spot of the calibration light source 134 in the optical inspection equipment 100 reaching the worktable through the laser processing head coincides with the solder joint of the worktable hit by the guiding red light or processing laser of the laser processing head. It can be seen that the optical inspection equipment 100 disclosed in this application, through the setting of the internal calibration light source 134, enables the optical inspection equipment 100 to achieve internal calibration before leaving the factory, thereby ensuring the optical path alignment of the multi-channel inspection optics in the optical inspection equipment 100 before leaving the factory. After the optical inspection equipment 100 leaves the factory, during on-site calibration in the production environment, by comparing the overlap between the optical axis of the calibration light source 134 and the optical axis of the processing laser, it can be achieved that the optical inspection equipment 100 can accurately align with the laser processing light signal radiation area under different laser welding process parameters, thereby obtaining more accurate data with a better signal-to-noise ratio.

[0080] The optical detection device 100 in this embodiment of the invention can be equipped with a beam splitter to divide the light to be tested into multiple bands according to testing requirements. The photodiodes responding to these bands can also be aligned with the light source using this method.

[0081] The sensor module of the present invention can also have a filter or aperture added in front of the photodiode to optimize the test signal according to the test requirements.

[0082] In some applications, the calibration light source 134 is a visible light laser source with a wavelength of up to 650nm.

[0083] In some embodiments, if the calibration light source 134 is a collimated light source, then it is not necessary to use the focusing lens 123 to collimate the beam.

[0084] In some embodiments, during calibration, the first aperture 330 set at the focal plane of the focusing lens 122 can be a center light-blocking aperture or an aperture that blocks light at both the center and the edge. The setting of the first aperture 330 not only facilitates the optical path calibration of the optical sensor, but also facilitates the selection of specific directions in the laser processing area, thereby improving the monitoring accuracy of the optical sensor.

[0085] For further details, please refer toFigure 9 This application also provides a laser processing inspection method, including the following steps:

[0086] Step 610: Receive the optical radiation signal of at least one processing point in the laser processing path through a photoelectric sensor. The optical radiation signal includes one or more of the following: infrared radiation signal, visible light radiation signal, and processing laser reflection signal.

[0087] Step 620: Determine the radiation area of ​​the processing point determined by the photoelectric sensor by using a first aperture set between the photoelectric sensor and the focusing lens of the beam splitter; wherein the position of the first aperture is approximately on the focal plane of the first focusing lens.

[0088] Step 630: Based on the shape of the aperture of the first aperture, determine whether the photoelectric sensor receives the center radiation light or the edge radiation light of the keyhole at the laser processing point.

[0089] In this embodiment, a focusing lens is set on the external radiation beam splitter path, and an aperture is set near the focal plane of the focusing lens. The radiation light entering the limited processing area of ​​the rear photoelectric sensor is selected by limiting the aperture of the aperture. This allows for precise selection of the radiation light in the processing area and reduces the impact of the vignetting effect on the intensity of the radiation light on the photosensitive surface of the photoelectric sensor.

[0090] It is understandable that the first aperture is a central light-blocking aperture, which filters out the radiation light from the center of the keyhole at the laser processing point.

[0091] For the sake of simplicity, all actions in this application are described as a series of combinations of actions. However, those skilled in the art should understand that this application is not limited to the described order of actions, as some steps may be performed in other orders or simultaneously according to this application. Furthermore, those skilled in the art should also understand that some steps involved in the embodiments described in the specification are not necessarily essential to this application.

[0092] Although this application has been described herein in conjunction with various embodiments, those skilled in the art, by reviewing the accompanying drawings, disclosure, and appended claims, will understand and implement other variations of the disclosed embodiments in carrying out the claimed application. In the claims, the word "comprising" does not exclude other components or steps, and "a" or "an" does not exclude multiple instances. While different dependent claims may recite certain measures, this does not mean that these measures cannot be combined to produce a good effect.

[0093] Those skilled in the art will understand that all or part of the steps in the various methods of the above calibration method embodiments can be implemented by a program instructing related hardware. The program can be stored in a computer-readable storage device, which may include: a flash drive, a read-only memory (ROM), a random access memory (RAM), a magnetic disk, or an optical disk, etc.

[0094] The above description represents the preferred embodiments of the present invention. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principles of the present invention, and these improvements and modifications are also considered to be within the scope of protection of the present invention.

Claims

1. An optical inspection device, characterized in that: Includes a housing, a beam splitter, a first photoelectric sensor, and a first aperture; The housing has a light-transmitting hole for receiving radiation light from the external detection area; and the radiation light from the light-transmitting hole is processed by the built-in beam-splitting optical path and the first photoelectric sensor. The beam-splitting optical path has a first focusing lens. The beam-splitting optical path is used to receive the radiated light from the external detection area that enters the housing through the light-transmitting hole, and to focus the radiated light onto the photosensitive surface of the first photoelectric sensor through the first focusing lens. The first photoelectric sensor receives the first band optical signal from the split optical path; The first aperture is positioned between the first photoelectric sensor and the first focusing mirror of the beam splitter, and the position of the first aperture is approximately on the focal plane of the first focusing mirror; so that the first band light signal reaches the photosensitive surface of the first photoelectric sensor after passing through the first aperture.

2. The optical inspection device according to claim 1, characterized in that: The first aperture is located at the focal plane of the first focusing lens; the first photoelectric sensor is an infrared photoelectric sensor, which receives the first band light signal as the infrared light radiation signal of the processing point during laser processing.

3. The optical inspection device according to claim 1, characterized in that: It also includes a second photoelectric sensor and a second aperture; The beam-splitting optical path also has a second focusing mirror. The beam-splitting optical path is used to separate the radiated light into at least two different frequency bands. The first band optical signal is output to the first photoelectric sensor through the first focusing mirror, and the second band optical signal is output to the second photoelectric sensor through the second focusing mirror. The first band optical signal and the second band optical signal are different. The second aperture is positioned between the second photoelectric sensor and the second focusing lens, and the second aperture is located on or near the focal plane of the second focusing lens; so that the second-band light signal reaches the photosensitive surface of the second photoelectric sensor after passing through the second aperture.

4. The optical inspection device according to claim 3, characterized in that: The second aperture is located at the focal plane of the second focusing lens; and the light-passing aperture of the first aperture is different from that of the second aperture.

5. The optical inspection device according to any one of claims 1, 2, and 3, characterized in that: The first and / or second apertures are central light-blocking apertures, which filter out the radiated light in a certain area in the middle of the aperture.

6. The optical inspection device according to claim 5, characterized in that: It also includes a calibration light source located inside the housing, which radiates calibration light into the beam splitter and then through the light-transmitting hole in the housing to the external detection area.

7. The optical inspection device according to claim 6, characterized in that: A focusing lens is installed at the light-passing hole or outside the optical detection equipment. The imaging system formed by the focusing lens and the first focusing lens makes the processing point of the external detection area and the light-passing hole of the first aperture form an object-image relationship. It is used to collimate the radiation light of the processing point of the external detection area into parallel light, and transmit the parallel light to the first focusing lens through the beam splitting optical path, and then focus it onto the central light-blocking aperture through the first focusing lens. The beam splitter is also used to radiate the calibration light from the calibration light source to the light aperture, so that the calibration light at the light aperture and the external radiation light are coaxial on the optical axis of the light aperture.

8. The optical inspection device according to claim 2 or 3, characterized in that: The beam splitting optical path includes multiple beam splitters arranged in parallel segments along the optical axis of the light-passing aperture and set at a certain angle to the optical axis; Each beam splitter is used to split the external radiation light from the optical axis of the aperture to the corresponding photoelectric sensor; Each beam splitter is connected to its corresponding photoelectric sensor by one or more of the following: a filter, a neutral density filter, and a focusing lens.

9. The optical inspection device according to claim 8, characterized in that: The calibration light source is positioned at the end of the last beam splitter, which is far from the light-transmitting aperture. This allows the calibration light to pass through multiple beam splitters arranged in parallel in sequence and then converge onto the external detection area through a focusing lens.

10. The optical inspection device according to claim 9, characterized in that: The calibration light source is set separately in one of the multiple beam splitters in the beam splitting optical path, and the calibration light radiated by the calibration light source is radiated to the light passage hole separately, so that the calibration light at the light passage hole and the external radiation light are coaxial on the optical axis of the light passage hole.

11. The optical inspection device according to claim 1, characterized in that: The housing includes an integrated bottom shell and a cover plate fixed to the top of the bottom shell; The bottom shell has an integrally formed reference bottom surface and multiple outer side walls surrounding the bottom surface, which together form an internal cavity. A light-transmitting hole is opened on one of the outer side walls of the multi-faceted outer wall, through which radiation light from the external detection area is received; The base surface of the bottom shell extends upward to form a mounting base integrally formed with the bottom shell; The mounting base includes one or more of a beam splitter mounting base, a condenser lens mounting base, a neutral density filter mounting base, and a calibration light source mounting base; The mounting base is used to embed or fix the corresponding beam splitting optical path, the first photoelectric sensor, the second photoelectric sensor, and the calibration light source; wherein, the beam splitting optical path includes one or more of a beam splitter, a condenser, a neutral density filter, and a filter.

12. A laser processing inspection method, characterized in that: Applied to any one of the optical inspection devices described in claims 1-11, the inspection method includes the following steps: The optical radiation signal at least one processing point in the laser processing path is received by a photoelectric sensor. The optical radiation signal includes one or more of the following: infrared radiation signal, visible light radiation signal, and processing laser reflection signal. The radiation light region of the processing point determined by the photoelectric sensor is determined by a first aperture set between the photoelectric sensor and the focusing lens of the beam splitter; wherein the position of the first aperture is approximately on the focal plane of the first focusing lens. Based on the shape of the light-transmitting aperture of the first aperture, determine whether the photoelectric sensor receives the central radiation light or the edge radiation light from the keyhole of the laser processing point.

13. The optical path calibration method according to claim 12, characterized in that: The first aperture is a central light-blocking aperture, which filters out the radiation light from the center of the keyhole at the laser processing point.

Images