Image acquisition device and sorting machine

Abstract

The present disclosure relates to the field of material sorting, and particularly relates to an image acquisition device and a sorting machine, wherein the image acquisition device is applied to the sorting machine with a conveying device, and the image acquisition device comprises at least one light source for emitting light to irradiate materials on the conveying device and excite the materials to generate fluorescence; a camera for receiving the fluorescence and outputting image data of the materials; and a lens mounted on the camera for allowing the fluorescence to pass through the lens and be received by the camera, wherein the lens is a large-aperture lens to enhance the signal intensity of the image data. The amount of light passing through the lens per unit time can be increased, the signal intensity of the image data can be enhanced, the efficient transmission of the fluorescence signal can be ensured, and the intensity and stability of the image data are further enhanced. The accuracy of material sorting is improved, the efficiency of material sorting is improved, and the long-term stable operation of material sorting is ensured.

Description

Technical Field

[0001] This disclosure relates to the field of material sorting, specifically to an image acquisition device and a sorting machine. Background Technology

[0002] In some material sorting scenarios, such as the sorting of spodumene, spodumene can produce fluorescence of a specific wavelength under ultraviolet light. This property can be used to distinguish spodumene from lithium ore and other associated minerals. However, because the fluorescence effect of spodumene is relatively weak, obtaining a sufficiently bright fluorescence image of spodumene is difficult, resulting in a decrease in sorting efficiency. Utility Model Content

[0003] To overcome the problems existing in the related art, an exemplary embodiment of the present disclosure provides an image acquisition device for use in a sorting machine with a transmission device. The image acquisition device includes: at least one light source for emitting light to illuminate material on the transmission device and excite the material to produce fluorescence; a camera for receiving the fluorescence and outputting image data of the material; and a lens mounted on the camera for allowing the fluorescence to pass through the lens and be received by the camera, wherein the lens is a large aperture lens to enhance the signal strength of the image data.

[0004] In some embodiments, the aperture factor of the lens is less than or equal to 2.8.

[0005] In some embodiments, the image acquisition device further includes a filter disposed in the optical path of the lens for filtering out reflected light and transmitting the fluorescence.

[0006] In some embodiments, the camera is configured as a time-delay integral camera.

[0007] In some embodiments, the camera's exposure time is less than or equal to 100 microseconds.

[0008] In some embodiments, two light sources are provided, with the two light sources respectively located on both sides of the optical axis of the lens.

[0009] In some embodiments, the light rays emitted by the two light sources intersect to form a light spot overlap area, and the light spot overlap area is located above the transmission device.

[0010] In some embodiments, the angle between the center line of the light emitted by the light source and the optical axis of the lens is 6-12 degrees.

[0011] Secondly, this disclosure also provides a sorting machine for material sorting, comprising: a conveying device for conveying materials; an image acquisition device as described in the first aspect for identifying the materials conveyed by the conveying device to obtain the category of the materials; and a sorting device for sorting the materials according to the identification result of the image acquisition device.

[0012] In some embodiments, the vertical distance between the light source and the surface of the transmission device is 150-250 mm.

[0013] It should be understood that the above general description and the following detailed description are exemplary and explanatory only, and are not intended to limit this disclosure.

[0014] This disclosure provides an image acquisition device, comprising at least one light source, a camera, and a large-aperture lens. The image acquisition device can emit light from at least one light source to illuminate materials and induce fluorescence. The camera can receive the fluorescence and convert it into image data, providing a basis for material sorting. The lens employs a large aperture, which increases the amount of fluorescence light passing through the lens per unit time, thereby enhancing the signal strength of the image data and ensuring efficient transmission of the fluorescence signal, further improving the strength and stability of the image data. This improves the accuracy and efficiency of material sorting, ensuring long-term stable operation of the material sorting system. Attached Figure Description

[0015] This disclosure can be better understood by describing exemplary embodiments of the present disclosure in conjunction with the accompanying drawings, in which:

[0016] Figure 1 This is a schematic diagram of an image acquisition device according to a disclosed exemplary embodiment;

[0017] Figure 2 This is a schematic diagram of an image acquisition device according to another disclosed exemplary embodiment. Detailed Implementation

[0018] The following describes specific embodiments of this disclosure. It should be noted that, in order to provide a concise description, this specification cannot exhaustively describe all features of the actual embodiments. It should be understood that, in the actual implementation of any embodiment, just as in any engineering or design project, various specific decisions are often made to achieve the developer's specific goals and to meet system-related or business-related constraints, and this can change from one embodiment to another. Furthermore, it is understood that although the efforts made in this development process may be complex and lengthy, for those skilled in the art related to the content of this disclosure, some design, manufacturing, or production modifications based on the technical content disclosed in this disclosure are merely conventional technical means and should not be construed as insufficient content of this disclosure.

[0019] Unless otherwise defined, the technical or scientific terms used in the claims and description shall have the ordinary meaning understood by one of ordinary skill in the art to which this utility model pertains. The terms "first," "second," and similar words used in the specification and claims of this utility model patent application do not indicate any order, quantity, or importance, but are merely used to distinguish different components. The terms "an" or "a" and similar words do not indicate a quantity limitation, but rather indicate the presence of at least one. The terms "comprising" or "including" and similar words mean that the element or object preceding "comprising" or "including" encompasses the element or object listed following "comprising" or "including" and its equivalents, and do not exclude other elements or objects. The terms "connected" or "linked" and similar words are not limited to physical or mechanical connections, nor are they limited to direct or indirect connections.

[0020] In some scenarios, such as the sorting of materials like spodumene, spodumene can produce fluorescence of a specific wavelength under ultraviolet light irradiation, thus distinguishing it from lithium ore and other associated minerals. Because the fluorescence effect of spodumene is relatively weak, some existing technologies aim to enhance its fluorescence effect by increasing the power and number of ultraviolet light sources. However, stacking multiple light sources results in excessive power consumption for the overall equipment. Another approach is to increase the ultraviolet irradiation intensity on the ore surface by compressing the height of the light source above the conveyor belt, also aiming to enhance the fluorescence effect. However, multiple ultraviolet light sources simultaneously irradiating the conveyor belt, and the close proximity of the light sources to the belt, accelerates belt aging and limits the height of ore that can pass through the equipment.

[0021] To overcome the problems existing in related technologies, an exemplary embodiment of this disclosure provides an image acquisition device applied to a sorting machine with a transmission device 210. The transmission device 210, used for conveying materials, can be a conveyor belt or the like, placing the materials on the belt and conveying them to the image acquisition device. The image acquisition device can detect the materials through a light source emitting end and a receiving end disposed above the belt, thereby determining the material category and performing sorting. The sorting machine may further include a sorting unit, used to sort materials according to the recognition results of the image acquisition device, separating materials of different categories. For example, Figure 1 , Figure 2 As shown, the image acquisition device may include at least one light source 110, a camera 120, and a lens 130.

[0022] At least one light source 110, such as Figure 1 , Figure 2 As shown, the light source 110 is used to emit light to illuminate the material on the conveyor 210 and excite the material to fluoresce. The light source 110 can be fixed to the bracket of the sorting machine, positioned directly above or to the side of the conveyor belt. The light source 110 can be electrically connected to the sorting machine's control system and can receive control signals to turn on or off; for example, the light source 110 is turned on when the conveyor belt is running and turned off when the conveyor belt is stopped. The light source 110 can emit light of a specific wavelength, such as ultraviolet light, which illuminates the material on the conveyor 210, causing the spodumene in the material to emit red fluorescence different from the wavelength of the ultraviolet light source, providing a signal source for the camera 120 to acquire images.

[0023] The center wavelength of the light source 110 can be set to 350-380 nanometers, such as 365 nanometers or 367 nanometers. The bandwidth of the light source 110 can be 25-35 nanometers, such as 30 nanometers, which can broaden the illumination range of the light source 110 and increase the amount of reflected fluorescent light. The power of a single ultraviolet light source can be less than 1000 watts, which can reduce the damage caused by ultraviolet rays to the belt, extend the belt life, and greatly reduce the operating cost of the equipment, making it economical and environmentally friendly.

[0024] Light source 110 can be set to one, two, or more. For example... Figure 2 As shown, using a single light source 110 can reduce costs, save resources, and minimize UV ​​damage to the belt. For example... Figure 1 As shown, two light sources 110 are set up, which can be positioned on both sides of the optical path relative to the camera 120. This can increase the amount of light reflected by the material's fluorescence and improve the intensity of the image data. Setting up multiple light sources 110 makes the material more evenly illuminated, further increasing the amount of light reflected by the material's fluorescence.

[0025] The angle between the light source 110 and the center of the camera 120 can be set according to the material at different heights, ensuring that the light source 110 can effectively illuminate the surface of the ore. The height of the light source 110 from the transmission device can also be set, which not only ensures that the ore is illuminated, but also reduces the damage caused by ultraviolet rays to the belt, extends the belt life, and is conducive to the long-term stable operation of material sorting.

[0026] Camera 120, such as Figure 1 , Figure 2 As shown, the camera 120 is used to receive fluorescence and output image data of the material. It can be set at a certain angle to the light source 110 and can be fixed on the frame of the sorting machine, located above the conveyor 210. The camera 120 can receive the fluorescence signal of the material, convert it into image data, and output it for subsequent material sorting. The selection of the camera 120 can be based on the weak light characteristics of the material's fluorescence signal and the speed of the conveyor belt, ensuring clear and bright output image data, guaranteeing image data quality, facilitating judgment, and benefiting material sorting.

[0027] Lens 130, such as Figure 1 , Figure 2 As shown, it can be mounted on camera 120 to allow fluorescence to pass through lens 130 and be received by the camera. Lens 130 can be connected to camera 120 via an interface and is positioned at the front end of camera 120, allowing the fluorescence signal generated by the material on transmission device 210 to pass through lens 130 and be focused onto the photosensitive surface of camera 120. The optical axis of lens 130 coincides with the central axis of the photosensitive surface of camera 120, ensuring that the fluorescence signal excited by light source 110 can enter lens 130 to the maximum extent and reducing fluorescence signal loss.

[0028] Lens 130 can be a large-aperture lens to enhance the signal strength of image data. By setting lens 130 to a large aperture, the amount of light entering the fluorescence signal is increased, which directly enhances the signal strength of the image data. This effectively solves the problems of weak fluorescence signals and unclear and inaccurate image data, avoids misjudgment of target minerals due to image blur, and is beneficial for subsequent sorting, further improving sorting efficiency.

[0029] In some embodiments, the illumination area of ​​the light source 110, the imaging area of ​​the lens 130, and the photosensitive area of ​​the camera 120 can overlap to ensure that the light convergence point of the light source 110, the focus center point of the lens 130, and the center of the photosensitive surface of the camera 120 are on the same vertical line. This ensures that the light source 110 illuminates the material, and that the fluorescence emitted by the material passes through the imaging area of ​​the lens 130 to reach the photosensitive area of ​​the camera 120. This ensures that the photosensitive area of ​​the camera 120 receives as much fluorescence signal as possible, thereby ensuring stronger signal strength in the output image data and stable image data quality. This can further improve the accuracy and efficiency of subsequent material sorting.

[0030] In some embodiments, such as Figure 1 As shown, light source 110 first emits ultraviolet light with a center wavelength of 367nm and a bandwidth of 30. The light emitted by the two light sources 110 propagates along both sides of the optical axis of lens 130, illuminating the material on transmission device 210. The spodumene in the material is excited, producing red fluorescence with a wavelength different from the ultraviolet light, forming the fluorescence signal to be collected. Subsequently, the red fluorescence diverges towards lens 130. Because lens 130 has a large aperture and its optical axis coincides with the central axis of the photosensitive surface of camera 120, the fluorescence can efficiently enter lens 130, reducing fluorescence signal loss. Finally, the focused red fluorescence is projected along the optical path onto the photosensitive surface of camera 120. The photosensitive surface receives the fluorescence and converts it into an image signal, completing the complete light path from excitation by light source 110 to transmission by lens 130 and reception by camera 120. This allows for the output of stable and clear image data, preparing for subsequent material sorting.

[0031] In this embodiment, the image acquisition device, through the cooperation of the light source 110, camera 120, and lens 130, can achieve efficient sorting of materials such as spodumene. By setting the wavelength and bandwidth of the light source 110, the illumination range can be widened, and the low power of the light source 110 reduces the aging damage of ultraviolet rays to the conveyor belt, extends its lifespan, and lowers energy consumption and operating costs. The angle and height of the light source 110 can be adjusted to match materials of different heights, avoiding problems such as missed illumination and uneven lighting. The camera 120 can be selected based on the weak characteristics of fluorescence and the conveyor belt speed, outputting clear and bright image data, providing reliable images for sorting, and reducing misjudgments caused by unclear or inaccurate images. The large-aperture lens 130 enhances the fluorescence signal by increasing the amount of light entering the lens, ensuring efficient transmission of the fluorescence signal, further enhancing the intensity and stability of the image data. This image acquisition device 100 improves the sorting accuracy and efficiency of materials such as spodumene, while reducing the frequency of equipment maintenance, ensuring long-term stable operation of the sorting process, and balancing environmental protection and economic efficiency.

[0032] In some embodiments, the aperture factor of lens 130 is less than or equal to 2.8. The aperture factor is the ratio of the lens focal length to the effective aperture diameter. Setting the aperture factor of lens 130 to a smaller value results in a relatively larger aperture diameter, increasing the amount of light transmitted per unit time. In some embodiments, setting the aperture factor of lens 130 to 2.8 allows for the focusing of as much fluorescence emitted from the mineral surface as possible onto camera 120. In other embodiments, the aperture factor of lens 130 can be less than 2.8, for example, an aperture factor of 2. Compared to setting the aperture factor to 2.8, this further focuses the fluorescence signal onto camera 120, enhancing the signal strength of the image data. When the aperture factor is set to 1.4, the large aperture of lens 130 significantly increases the amount of fluorescence light per unit time, resulting in clearer, higher-quality output image data that is easier to interpret.

[0033] In this embodiment, by setting the aperture coefficient of lens 130 to a low value, as much fluorescence signal as possible can be focused onto camera 120 per unit time. This, combined with a low-power light source 110, allows for the enhancement of limited fluorescence signals through a larger aperture, enabling the acquisition of high-quality images without the need for strong light. This ensures the quality of image data and improves the accuracy and efficiency of subsequent sorting.

[0034] In some embodiments, such as Figure 1 , Figure 2 As shown, the image acquisition device may further include a filter 140, disposed in the optical path of the lens 130, for filtering out reflected light and transmitting fluorescence. A slot for the filter 140 can be provided at the front end of the lens 130. The filter 140 can be fixed in the slot by a snap or thread, directly intercepting stray light entering the lens 130. Installation and replacement are convenient without disassembling the lens 130 and camera 120. The filter 140 can be set to red to filter out stray light other than fluorescence. Stray light may include ultraviolet light reflected from the mineral surface and other light rays. If the material to be sorted is spodumene, the surface of the ore will emit a bright red fluorescence. The fluorescence emitted by the ore surface will pass through the filter 140 and then be focused by the lens 130 onto the photosensitive surface of the camera 120, and the camera 120 will output a bright image of the ore. If the material to be sorted is not spodumene, the surface of the ore will not emit fluorescence. Most of the ultraviolet light reflected from the ore surface will be filtered out by the filter 140, and only a small amount of light will reach the photosensitive surface of the camera 120, and the camera 120 will output a dim image of the ore.

[0035] In this embodiment, by setting the filter 140, stray light can be efficiently filtered out. It can specifically block ultraviolet light reflected from the ore surface and other interfering light in the environment, allowing only the red fluorescence excited by spodumene to pass through efficiently, greatly reducing the interference of stray light on imaging and avoiding masking weak fluorescence signals. Moreover, the spodumene forms a bright and clear image after filtering, which is beneficial for subsequent algorithm recognition. Non-spodumene, because it has no fluorescence and reflects ultraviolet light, is greatly filtered out and only presents a dim image. The grayscale difference between the two is significantly amplified, providing a clear basis for accurate identification of target minerals in subsequent material sorting, ensuring the long-term accurate and efficient operation of sorting operations, and indirectly reducing equipment maintenance costs and sorting misjudgment rate.

[0036] In some embodiments, camera 120 is configured as a time-delay integration (TDI) camera. A time-delay integration camera can increase signal strength by a factor of two within the same exposure time by accumulating the signal. Under the same lighting conditions and imaging lens conditions, it can enhance the brightness of the camera's output image.

[0037] In some embodiments, after the camera 120 uses the time delay integration function, in conjunction with the large aperture lens 130, the time delay integration camera 120 can acquire sufficiently bright spodumene fluorescence images under the condition of an exposure time of 100 microseconds. This can be matched with a faster belt speed to obtain more spodumene fluorescence images, thereby further improving the spodumene sorting yield.

[0038] In other embodiments, the exposure time of camera 120 can be less than 100 microseconds. When combined with a large aperture lens 130, the time-delay integration camera 120 can be matched with a faster belt speed, which can be 3000 mm / s, to obtain brighter fluorescent images of more spodumene and increase the sorting yield of spodumene.

[0039] In this embodiment, camera 120 is configured as a time-delay integration camera, working in conjunction with a large-aperture lens 130 to avoid weak fluorescence signals during short exposure times, thus achieving a dual improvement in sorting efficiency and image quality. The time-delay integration camera, through its signal accumulation characteristics, amplifies the fluorescence signal intensity many times over within the same exposure time. Combined with the high light intake of the large-aperture lens, even with an exposure time controlled at 100 microseconds, it can still capture sufficiently bright spodumene fluorescence images. This allows for matching with faster conveyor belt speeds, ensuring more effective images are acquired per unit time, laying the foundation for increased spodumene sorting output. If the exposure time is shortened to below 100 microseconds, this synergistic combination can better match a high-speed conveyor belt of 3000 mm / s, avoiding image blurring caused by material movement. Furthermore, due to signal accumulation and the large-aperture lens, brighter and clearer fluorescence images are obtained. While ensuring no decrease in sorting accuracy, this further increases the material throughput per unit time, significantly increasing spodumene sorting output and meeting the industrial demands for high-efficiency sorting.

[0040] In some embodiments, such as Figure 1 As shown, two light sources 110 can be configured, with each light source 110 positioned on either side of the optical axis of the lens 130. Using two light sources 110 saves costs, reduces damage to the conveyor belt caused by ultraviolet light emitted from the ultraviolet light source, and extends the belt's lifespan. The two light sources 110 can be symmetrically distributed on either side of the lens 130. In some cases, a single light source may not be sufficient for irradiating the material; two light sources 110 can irradiate from both sides of the material, complementing each other and ensuring a larger irradiated area with sufficient fluorescence. In this embodiment, irradiating the material from both sides provides uniform, high-intensity ultraviolet excitation light to the material on the conveyor 210, ensuring that more spodumene is effectively excited and produces stable red fluorescence. This provides sufficient and uniform light for the lens 130 and camera 120, suitable for high-speed conveyor belt operation and complex material conditions in spodumene sorting scenarios, providing reliable assurance for subsequent imaging and sorting.

[0041] In some embodiments, such as Figure 1As shown, the light rays emitted by the two light sources 110 intersect to form a beam overlap area, which is located above the transmission device 210. The two light sources 110 are respectively positioned on either side of the optical axis of the lens 130. The light rays can intersect during propagation, forming a beam overlap area above the transmission device 210. This beam overlap area can cover the material surface. Compared to a non-intersecting design, the beam overlap area can excite more red fluorescence in the spodumene on the transmission device 210, increasing the fluorescence intensity of the spodumene and thus obtaining clearer and brighter image data. The height of the beam overlap area from the transmission device 210 can be set according to the average height of the spodumene sample to be sorted, and can be 15 mm.

[0042] In this embodiment, two light sources 110 are respectively positioned on either side of the optical axis of the lens 130. Their light rays intersect above the transmission device 210 to form a light spot overlap area. The technical effect is that it can achieve light focusing and efficient fluorescence excitation. This overlap area can directly cover the material surface. Compared with a design where the light rays do not intersect, it can superimpose the energy of the two ultraviolet light beams, significantly increasing the energy density in the area. This allows the spodumene on the transmission device 210 to excite more red fluorescence, greatly enhancing the fluorescence intensity and solving the problems of energy dispersion and insufficient local excitation in single light sources or non-overlapping dual light sources. Furthermore, the stronger fluorescence signal provides a more sufficient imaging source for the camera 120. Combined with the lens 130 and filter 140, it can output clearer and brighter image data, effectively improving the grayscale difference between spodumene and non-spodumene, reducing the misjudgment rate of subsequent sorting algorithms, and providing a reliable guarantee for the accuracy and efficiency of sorting operations.

[0043] In some embodiments, such as Figure 1 , Figure 2 As shown, the angle between the center line of the light emitted by light source 110 and the optical axis of lens 130 is 6-12 degrees. When the angle between the center line of the light emitted by light source 110 and the optical axis of lens 130 is less than 6 degrees, the light is too close to the optical axis of lens 130, which may cause the excited red fluorescence to not be accurately focused into lens 130. If the angle between the center line of the light emitted by light source 110 and the optical axis of lens 130 is too large, that is, the divergence angle of the light is too large, it may cause energy dispersion, making it difficult to excite the weakly fluorescent low-grade spodumene, and may also occupy a certain amount of space. The angle between the center line of the light emitted by the light source 110 and the optical axis of the lens 130 can be set according to the average height of the spodumene sample, which can be 8 degrees. The overlapping area of ​​the light spot can be directly located on the surface of the spodumene sample, so that the material can fully excite the red fluorescence signal and effectively transmit it to the lens 130. The fluorescence signal can be imaged on the TDI camera, which can obtain a clear and bright image of spodumene, improve the accuracy of the sorting algorithm, and thus affect the subsequent imaging and sorting accuracy, thereby improving the sorting accuracy and sorting yield of spodumene.

[0044] Based on the same inventive concept, an exemplary embodiment of this disclosure also provides a sorting machine that can be used for material sorting, including: a conveying device 210, such as the image acquisition device in the foregoing embodiment, and a sorting device.

[0045] The conveying device 210 can be used to transport materials. The conveying device 210 can be a conveyor belt or the like, and materials can be placed on the conveying device 210 and transported to the image acquisition device through the conveying device 210.

[0046] The image acquisition device may include at least one light source 110, a camera 120, and a large-aperture lens 130. The image acquisition device can emit light through at least one light source 110 to illuminate the material and cause it to fluoresce. The camera 120 can receive the fluorescence and convert it into image data, providing a basis for material sorting. The lens 130, with its large aperture, can increase the amount of fluorescence light passing through the lens per unit time, enhancing the signal strength of the image data and ensuring efficient transmission of the fluorescence signal, further improving the strength and stability of the image data. This improves the accuracy of material sorting, thereby increasing the efficiency of material sorting and ensuring its long-term stable operation.

[0047] A sorting device can be used to sort materials based on the recognition results of an image acquisition device. The sorting device can be installed downstream of a conveyor system, and it can separate materials according to their category, thus separating different types of materials.

[0048] The sorting machine of this embodiment can transport materials via the conveyor 210, facilitating identification and classification by the identification device. Based on the image acquisition device's identification and classification of materials, and finally the sorting device's separation of different types of materials, it can accurately and quickly classify and sort the materials to be tested, achieving high identification and sorting accuracy. The image acquisition device, through the cooperation of the light source 110, camera 120, and lens 130, can achieve efficient sorting of materials such as spodumene. By setting the wavelength and bandwidth of the light source 110, the illumination range of the light can be widened, and the light source 110 is set to a lower power, which reduces the aging damage of ultraviolet light to the belt, extends the belt life, and reduces energy consumption and operating costs. The angle and height of the light source 110 can be adjusted to match materials of different heights, avoiding problems such as missed illumination and uneven light distribution. The camera 120 can be selected based on the weak fluorescence characteristics and belt speed, outputting clear and bright image data, providing reliable data for sorting and reducing misjudgments caused by unclear or inaccurate images. The large-aperture lens 130 enhances the fluorescence signal by increasing the amount of light entering the lens, ensuring efficient transmission of the fluorescence signal and further improving the intensity and stability of the image data. This image acquisition system 100 improves the sorting accuracy and efficiency of materials such as spodumene, while reducing the frequency of equipment maintenance, ensuring long-term stable operation of the sorting process, and balancing environmental protection and economic efficiency.

[0049] In some embodiments, the vertical distance between the light source 110 and the surface of the transmission device 210 is 150-250 mm. When the vertical distance between the light source 110 and the surface of the transmission device 210 is less than 150 mm, the light source 110 is too close to the belt. On the one hand, the ultraviolet radiation on the belt surface is too high, which will accelerate the aging of the belt rubber and increase the cost of consumable replacement; on the other hand, the light spot coverage is narrow, which cannot cover the imaging of ores at different heights, and taller materials are prone to colliding with the light source 110. When the vertical distance between the light source 110 and the surface of the transmission device 210 is greater than 250 mm, the ultraviolet light energy will decrease with distance, the energy density of the overlapping area will decrease, and it will be difficult to excite the weak fluorescence of low-grade spodumene. The vertical distance between the light source 110 and the surface of the transmission device 210 can be set according to the average height of the spodumene sample, which can be 200 mm. This can make the energy of the overlapping area of ​​the light source 110 more stable, the light more uniform, extend the belt life, save costs, improve the excitation efficiency of the spodumene sample, and ensure the stable operation of the spodumene sorting image acquisition device.

[0050] In some embodiments, the image acquisition device may be mounted on a sorting machine bracket with two light sources 110 positioned at a vertical distance of 150-250 mm (e.g., 200 mm) from the surface of the transmission device 210. These light sources are located on either side of the optical axis of the lens 130, with the center line of the light beam forming an angle of 6-12 degrees (e.g., 8 degrees) with the optical axis. The light sources first emit ultraviolet light with a center wavelength of 350-380 nm (e.g., 367 nm), a bandwidth of 25-35 nm (e.g., 30 nm), and a power of less than 1000 watts. The two beams intersect to form a light spot overlap area covering the surface of the material (highly adapted to the average thickness of spodumene, e.g., 15 mm), which can illuminate the material on the transmission device 210. The spodumene in the material is stimulated to produce red fluorescence, while non-spodumene reflects ultraviolet stray light. The fluorescence and stray light propagate towards the lens 130, first passing through the red filter in the front slot of the lens 130. The light filter 140 filters out most of the ultraviolet reflected light and ambient stray light, allowing only red fluorescence to pass through efficiently. The transmitted red fluorescence then enters the large-aperture lens 130 with an aperture factor of less than or equal to 2.8 (such as 2.8, 2, or 1.4). Because the optical axis of the lens coincides with the central axis of the photosensitive surface of the camera 120, the fluorescence is focused by the lens, reducing signal loss. Finally, the focused red fluorescence is projected onto the photosensitive surface of the TDI camera 120 along the optical path. The TDI camera, through its signal accumulation function (adapted to short exposures of less than or equal to 100 microseconds, and can match belt speeds of 3000 mm / s), can convert the fluorescence signal into clear and stable image data, completing the entire light transmission path from excitation by the light source 110, stray light filtering, lens focusing, to reception by the camera 120, providing high-quality image data for subsequent spodumene sorting. This improves the sorting accuracy and efficiency of materials such as spodumene, while reducing the equipment maintenance frequency, ensuring long-term stable operation of the sorting process, and balancing environmental protection and economy.

[0051] This application uses specific terms to describe embodiments of the application. Terms such as "an embodiment," "one embodiment," and / or "some embodiments" refer to a particular feature, structure, or characteristic associated with at least one embodiment of the application. Therefore, it should be emphasized and noted that references to "an embodiment," "one embodiment," or "an alternative embodiment" in different locations throughout this specification do not necessarily refer to the same embodiment. Furthermore, certain features, structures, or characteristics in one or more embodiments of the application can be appropriately combined.

[0052] In the context of this application, unless the context clearly indicates otherwise, the words "a," "an," "an," and / or "the" do not specifically refer to the singular and may also include the plural. Generally speaking, the terms "comprising" and "including" only indicate the inclusion of explicitly identified steps and elements, which do not constitute an exclusive list, and the method or apparatus may also include other steps or elements.

[0053] Similarly, it should be noted that, in order to simplify the description of the present application and thus aid in the understanding of one or more embodiments, the foregoing description of the embodiments of the present application sometimes combines multiple features into a single embodiment, drawing, or description thereof. However, this disclosure method does not imply that the subject matter of the present application requires more features than those mentioned in the claims. In fact, the embodiments contain fewer features than all the features of the single embodiments disclosed above.

[0054] The basic concepts have been described above. Obviously, for those skilled in the art, the above disclosure is merely illustrative and does not constitute a limitation of this application. Although not explicitly stated herein, those skilled in the art may make various modifications, improvements, and corrections to this application. Such modifications, improvements, and corrections are suggested in this application, and therefore remain within the spirit and scope of the embodiments of this application.

Claims

1. An image acquisition device, applied to a sorting machine with a transmission device, the image acquisition device comprising: At least one light source is provided for emitting light to illuminate the material on the transmission device and to excite the material to produce fluorescence. A camera is used to receive the fluorescence and output image data of the material; A lens, mounted on the camera, is used to allow the fluorescence to pass through the lens and be received by the camera, wherein the lens is a large aperture lens to enhance the signal strength of the image data.

2. The image acquisition device according to claim 1, wherein, The aperture value of the lens is less than or equal to 2.

8.

3. The image acquisition device according to claim 1, wherein, The image acquisition device further includes a filter, which is disposed in the optical path of the lens to filter out reflected light and transmit the fluorescence.

4. The image acquisition device according to any one of claims 1-3, wherein, The camera is configured as a time-delay integral camera.

5. The image acquisition device according to claim 4, wherein, The camera's exposure time is less than or equal to 100 microseconds.

6. The image acquisition device according to claim 1, wherein, The light source is configured as two, and the two light sources are respectively located on both sides of the optical axis of the lens.

7. The image acquisition device according to claim 6, wherein, The light rays emitted by the two light sources intersect to form a light spot overlap area, and the light spot overlap area is located above the transmission device.

8. The image acquisition device according to claim 6 or 7, wherein, The angle between the center line of the light emitted by the light source and the optical axis of the lens is 6-12 degrees.

9. A sorting machine for sorting materials, comprising: A conveying device used to transport materials; The image acquisition device according to any one of claims 1-8 is used to identify the material transported by the transmission device to obtain the category of the material; The sorting device is used to sort the materials based on the recognition results of the image acquisition device.

10. The sorting machine according to claim 9, wherein, The vertical distance between the light source and the surface of the transmission device is 150-250 mm.

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