109 results about "Black spot" patented technology

The invention relates to the technical field of image recognition, in particular to a plastic particle black spot defect online detection method based on deep learning. Performing non-linear space conversion on the original image, and separating a background field component and a significance component; constructing a reverse compensation item by using the background field component, carrying out dynamic gain correction on an original brightness channel, and carrying out multi-channel weighted fusion on the original brightness channel and the saliency component to generate a saliency feature map; inputting the saliency feature map into a multi-scale topology enhancement network, extracting edge distribution features, and performing closed contour extraction and Euclidean distance transformation to generate a topology thickness energy map; the high-frequency gradient magnitude of the original image is calculated, mask smoothing processing is carried out on the gradient of the black spot region by using the saliency feature map, and a joint dissipation field is constructed; and taking a local maximum value point in the topological thickness energy diagram as a morphology seed point, executing controlled watershed evolution under the topological constraint of the joint dissipation field, realizing boundary stripping of an adhesive particle region, and generating a particle morphology diagram.

The invention relates to an insect pest detection processing method, system and device, and belongs to the field of insect pest detection.The method comprises the steps that a crop image in a target area is collected, black spot recognition and malformation recognition are conducted on the crop image, and black spot parameters and malformation parameters are obtained; according to the black spot parameter and the malformation parameter, calculating to obtain a first insect pest parameter, and configuring an insect body detection range and an insect body detection scale; collecting a detection image set, and carrying out insect body recognition to obtain an insect body recognition result; and processing according to the insect body identification result to obtain a second insect pest parameter, and calculating to obtain an insect pest parameter as an insect pest detection processing result in combination with the first insect pest parameter. According to the method, the technical problems of inaccurate detection and low treatment efficiency caused by the fact that pest distribution characteristics are not considered in mangosteen pest detection in the prior art are solved, and the technical effects of analyzing the pest distribution characteristics through crop pest symptoms, optimizing a detection strategy and improving pest detection accuracy and treatment efficiency are achieved.

The invention provides a glass bottle black spot detection method and device, electronic equipment and a storage medium, and relates to the technical field of glass bottle quality detection.The method comprises the steps that each group of light sources are controlled to irradiate the surface of a to-be-detected glass bottle at different incident angles; collecting multi-angle image information of the surface of the glass bottle irradiated by the plurality of groups of light sources; extracting an average gray value for each suspected black spot region in the multi-angle image information; calculating a linear regression slope corresponding to each suspected black spot area by constructing a linear regression model; and comparing the absolute value of the linear regression slope with a preset slope threshold value to distinguish dust and black spots. According to the glass bottle black spot detection method, on the premise that an existing reflection type optical hardware system is not changed and the investment of dust removal equipment is not remarkably increased, dust and black spots on the glass bottle are more accurately distinguished, the misjudgment rate is remarkably reduced, and the stability of a detection system in a dust environment is improved.

The utility model relates to the field of glass bottle production dies, in particular to an opening ring and punch matching position for glass bottle forming. Comprising an opening ring which is arranged in an opening die and is positioned below the opening die, and a punch which moves up and down in the center of the opening ring and is matched with the opening ring, and the contact surface of the opening ring and the punch is only the opening at the uppermost end. The wear ring has the advantages that the upper portion of the wear ring is turned into the horn mouth, the contact area between the wear ring and the punch is reduced, abrasion between the wear ring and the punch is reduced, black spots generated when iron powder generated due to abrasion adheres to a bottle opening can be improved finally, the quality of glass products is improved, and the product percent of pass is increased.

This utility model relates to a locking and fixing device for optical films in an F-fold TV backlight module, comprising an elastic locking component hidden within the cavity of the F-fold back panel. The elastic locking component includes a side plate, with integrally formed spring tabs at its upper and lower ends. Each spring tab includes an elastic clamping portion and an elastic pressing portion located at the free end of the elastic clamping portion. A clamping groove is formed between the elastic clamping portions of the two spring tabs, used to elastically clamp the sides of the stacked optical film and diffuser plate. The outer surface of the side plate is bonded and fixed to the inner wall of the F-fold back panel cavity via an adhesive layer. The elastic pressing portions of the two spring tabs respectively press against the top and bottom walls of the F-fold back panel cavity. This utility model effectively prevents the optical film and diffuser plate from shaking back and forth during transportation or vibration testing, avoiding problems such as black spots caused by contact between the film and the LCD panel, vibration white spots caused by contact with the laminating auxiliary materials, and film detachment, thereby significantly reducing the product defect rate.

The invention relates to the field of ginseng black spot research, in particular to a slicer for ginseng black spot research, which comprises a placing mechanism, a lifting mechanism is arranged in the placing mechanism, and one end of the lifting mechanism penetrates and extends into the placing mechanism and is fixedly provided with a cutting mechanism. The top end of the lifting mechanism penetrates and extends out of the containing mechanism and is fixedly connected with a positioning mechanism, and a supporting mechanism is arranged at the top end of the interior of the containing mechanism. The ginseng can be placed in the placing groove, the pressing plate is pressed down to fix the ginseng, then the ginseng is cut through the cutting knife, the cut ginseng slices are taken out through the grid baffle, black spot on the ginseng can be observed, and the thickness of the next ginseng slice needing to be cut can be determined. Therefore, the height of the cutting knife is adjusted again to cut the ginseng slices with the corresponding thickness, and follow-up research is facilitated.

The application provides a silicon rod monitoring method and device and related equipment, wherein the method comprises: acquiring a first monitoring image of a to-be-detected silicon rod; performing image analysis on the first monitoring image to determine a number parameter of black spot regions in the first monitoring image and an area parameter of the black spot regions in the first monitoring image; and generating a warning information in a case where the number parameter is greater than or equal to a first threshold value and / or the area parameter is greater than or equal to a second threshold value. Through the acquisition of the first monitoring image of the to-be-detected silicon rod, the extraction of the number parameter and the area parameter of the black spot regions in the first monitoring image, and the generation of the warning information in a case where the number parameter and / or the area parameter indicate that the proportion of the black spots in the to-be-detected silicon rod is too large, an automatic monitoring mode is used to replace a manual inspection monitoring mode, human factors are avoided, the probability of false judgment of abnormal silicon rods or missed judgment of abnormal silicon rods is reduced, and the monitoring effect on the growth of the silicon rod is improved.

The application relates to the technical field of intelligent agriculture and plant protection, and particularly discloses a broccoli black spot early diagnosis system and method based on multi-modal machine learning fusion, which comprises a portable collection platform, a mobile experiment terminal and a server. The portable collection platform is integrated with a hyperspectral imaging camera, a chlorophyll fluorescence imager, a dark-adapted leaf clamp and a camera for sample barcode recognition, and is provided with an adjustable height support and a controllable light source to ensure the consistency of data collection conditions. The mobile experiment terminal is internally provided with a physicochemical index rapid detection module, including a portable PCR instrument for on-site nucleic acid rapid extraction and amplification and a miniature ultraviolet spectrophotometer for rapid determination of pigment content. The broccoli black spot early diagnosis system and method based on multi-modal machine learning fusion are highly integrated, portable and automated, are suitable for a field environment and provide an efficient disease diagnosis tool for non-expert users.

The application provides a PVC film preparation system and method based on industrial intelligent vision. In a stable production process of an extruder, an extruder screw torque signal and a melt temperature signal are collected, and a PVC film surface image sequence is obtained in real time. A black point density change rate per unit area in the PVC film surface image sequence is counted, and an area distribution feature of the black points in the PVC film surface image is extracted. A torque fluctuation amplitude in the screw torque signal and an over-threshold integral quantity of the melt temperature signal are calculated. The area distribution feature, the torque fluctuation amplitude and the over-threshold integral quantity are used to determine the causes of the black points in the PVC film preparation, and a determination result of the causes of the black points is obtained. Based on the black point density change rate and the cause category of the determination result, a parameter adjustment amount is calculated, and a speed adjustment amount and a maintenance time required to reduce the black point density to a target value are output. Based on the above scheme, cause category quantitative determination based on multi-source signal fusion can be realized.

The invention discloses a compound dispersing agent and a preparation method of polypropylene beads using the compound dispersing agent, and the compound dispersing agent contains EBS and Huawang EB-FF. Van der Waals force among pigment particles can be effectively overcome by using the compound dispersant, and the condition of pigment agglomeration is obviously inhibited, so that the conditions of black spots and generation change on the surface of a product are avoided.

The invention relates to the technical field of industrial data processing, and discloses an industrial data processing method for preparing a modified PC material, which comprises the following steps: acquiring an image of the surface of a product, identifying whether black spots exist on the surface of the product, judging the cause of the black spots on the surface of the product, and taking corresponding remedial measures. According to the industrial data processing method for preparing the modified PC material, black spot generation reasons are comprehensively and systematically analyzed, black spot distribution characteristics and potential reasons can be accurately positioned through image processing and statistical analysis, the accuracy of problem diagnosis is improved, a specific solution and improvement measures are provided, and the industrial data processing method is suitable for popularization and application. The method can be directly applied to quality control in the production process, helps enterprises and operators to quickly respond and solve quality problems, and helps to find potential problems in advance, take preventive measures, reduce defective products and improve production efficiency and product quality through comprehensive evaluation of raw materials, equipment and processes.

This application provides an electronic device. The electronic device includes a flexible display panel, a back panel, and a hinge, with the back panel disposed between the flexible display panel and the hinge. The flexible display panel includes a connected unfolding portion and a bending portion, the bending portion being used for bending the flexible display panel. The back panel has a first blind hole, which is located on one side of the back panel and away from the flexible display panel. The hinge has a slit. Using the surface of the flexible display panel as a reference plane, the projection of the first blind hole onto the reference plane at least partially overlaps with the projection of the slit onto the reference plane. The first blind hole helps prevent display defects such as bright spots, black spots, and dead pixels from appearing on the flexible display panel, thereby improving the lifespan of the electronic device.

The present application relates to the technical field of multi-stage cleaning of IGBT heat dissipation substrates, and solves the technical problem of black spot defects after chemical nickel plating caused by insufficient cleaning of oil stains in the pin fin microstructure of the heat dissipation substrate, especially a multi-stage cleaning method for inhibiting black spot defects of IGBT heat dissipation substrates. In the rough cleaning stage, the key parameters of the ultrasonic generator and the transducer are optimized, the heat dissipation substrate is subjected to rough cleaning, and the surface cleanliness is detected in real time. In the fine cleaning stage, the posture of the hyperspectral camera is accurately controlled for omnidirectional detection of the pin fin, the nozzle posture is adjusted based on the key information of the oil-stained pin fin, the nozzle output flow and pressure are controlled as the optimization target of the micro-flow column jet impact force, and the oil-stained pin fin is subjected to accurate cleaning. The present application realizes multi-angle omnidirectional oil stain cleaning and real-time cleanliness detection of each area on the surface of the heat dissipation substrate, thereby improving product quality to meet the requirements of downstream customers and effectively improving the core competitiveness in the industry.

The invention provides a cleaning agent for eliminating color difference defects of black spots on the surface of oriented silicon steel and application of the cleaning agent. In terms of 100 parts by mass of solvent content, the cleaning agent comprises 100 parts of solvent; 3 to 6 parts of citrate; 15-25 parts of an inorganic alkaline substance; 3-6 parts of organic amine; 0.5 to 1 part of a polycarboxylate flocculating agent; 0.03 to 0.06 part of a siloxane type surface active agent; 5-15 parts of hydrogen peroxide; the inorganic base is composed of a first inorganic base and a second inorganic base, the first inorganic base is carbonate, and the second inorganic base is hydroxide. The cleaning agent disclosed by the invention can be used for efficiently cleaning foreign matters such as oil stains and iron soap on a rolled plate surface in oriented silicon steel production, ensuring that precipitates formed in the cleaning process can be quickly separated from the cleaning agent, and meanwhile, ensuring that substances such as the residual cleaning agent can be efficiently cleaned after the plate surface is cleaned.

The application provides a bearing black spot defect detection method and device based on machine vision, and belongs to the field of industrial production. The detection method enhances an original image through an improved Gaussian filter image enhancement algorithm to obtain an enhanced image; performs ROI extraction on the enhanced image, and obtains an ROI image containing polar coordinates through polar coordinate transformation; performs twice irrelevant feature elimination on the ROI image to obtain a to-be-judged image; and determines whether the to-be-judged image contains surface defects by using a double-threshold processing method. The detection method provided in the application embodiment can reduce processing difficulty and improve the accuracy of bearing surface black spot defect detection.

This invention relates to the field of radiator technology and discloses a rapid detection device for brazing defects in radiators. The device includes: a positioning fixture, a machine structure, a vision camera, a detection and adjustment mechanism, and a marking mechanism. It uses a high-speed, high-precision vision camera, employing an upper light source to illuminate and inspect for light leaks, and a side light source to illuminate from the side to identify black spots at the weld joint. A closed-loop process is employed, featuring two symmetrical, two-degree-of-freedom adjustments, division of labor between the upper and side light sources, light shielding and anti-interference, and orthogonal marking by a dual-marking mechanism with defect coordinate mapping, to rapidly detect brazing defects. Marking is performed on the non-welding area of ​​the radiator to be inspected to identify the defect location, facilitating repair welding of products with appearance defects. The device improves detection accuracy, stability, and precision, reduces inspection costs, and decreases the number of appearance defects.

The invention discloses an orientation method for machining a single crystal. The orientation method comprises the following steps: step 1, leveling a to-be-machined surface of a single crystal material; step 2, determining a circular area with the largest area on the surface to be processed of the single crystal material; thirdly, a plurality of grooves are planed in the to-be-machined surface of the single crystal material, each groove extends to the edge of the circular area from the position close to the center of the circular area in the radial direction of the circular area, and the grooves are distributed around the center of the circular area in the circumferential direction at intervals; 4, the surface to be machined of the single crystal material is cleaned; 5, removing the grooves with black spots or cracks on the bottom surfaces; and 6, the bottom faces of the remaining grooves are subjected to morphology measurement in sequence to obtain the surface morphology characteristics of all the grooves, qualified grooves are screened out according to the surface morphology characteristics, and the extending direction of the qualified grooves is the optimal machining direction of the single crystal material. According to the method, the optimal processing direction of the single crystal material can be quickly determined.

The invention provides a display substrate and a display device, belongs to the technical field of display, and can solve the problem that an existing display substrate is prone to black spots and the like. The display substrate is provided with a hole opening area, a display area surrounding the hole opening area and a blocking area arranged between the hole opening area and the display area. The display substrate comprises a substrate body and an inorganic insulating layer located on the substrate body. The inorganic insulating layer is provided with a groove in the barrier region; the display substrate further comprises a first metal layer; the first metal layer covers the side face of the groove and is in lap joint with at least part of the bottom face of the groove and part of the surface, away from the substrate, of the inorganic insulating layer.

The invention discloses a display panel and a manufacturing method thereof, belongs to the technical field of display, and aims to at least solve the technical problem that black spots are easy to appear on a display panel in related technologies. The display panel comprises a substrate, at least one base and a plurality of partition structures, wherein the base and the partition structures are located on the substrate, and the base and the partition structures are located in a transition area of the display panel. The plurality of partition structures comprise at least one first partition structure, the first partition structure is supported on the corresponding base, and the orthographic projection of the base on the substrate is located in the range of the orthographic projection of the first partition structure on the substrate.

The invention provides a hyperspectrum-based citrus leaf lesion diagnosis system and a hyperspectrum-based citrus leaf lesion diagnosis method, and the hyperspectrum-based citrus leaf lesion diagnosis system and the hyperspectrum-based citrus leaf lesion diagnosis method disclosed by the invention have the advantages that on the basis of analyzing hyperspectral imaging data of citrus leaves without diseases, lack of nutrients, black spots and yellow shoot; three parameters of yellow wave band reflectivity, infrared wave band slope and inflection point wavelength are used as characteristic quantities, and classification of four types of blades is realized by applying a support vector machine (RBF-SVM) classification model based on a Gaussian radial basis kernel function. The method solves the problems that when citrus tree disease information is detected through a field detection method at present, long-time observation with eyes is needed, subjective judgment of observers is depended, and misjudgment is likely to be caused; according to the present invention, the problem that the citrus tree disease information detection by using the chemical detection method needs the special person to detect by using the professional equipment so as not to accurately and rapidly detect each production stage of the citrus tree can be solved, and the citrus leaf disease can be rapidly and accurately diagnosed.

A display panel is provided to improve the situation where moisture intrusion into the display area causes generative black spots. The display panel includes: a substrate, a plurality of sub-pixels, power lines, and an organic insulating layer. The substrate includes a display area and a first border area located on one side of the display area along a first direction. The first border area includes a bending area and a first wiring area located on the side of the bending area closer to the display area. The plurality of sub-pixels are located in the display area. The power lines are at least partially located in the first wiring area and are electrically connected to the plurality of sub-pixels. The organic insulating layer may be located on the side of the power lines away from the substrate, and an organic groove extending along a second direction is provided in the first wiring area, the organic groove penetrating the organic insulating layer. The power lines have at least one sidewall extending along the first direction, the edge length of the area where the at least one sidewall coincides with the orthographic projection of the organic groove onto the substrate is greater than the minimum length of the organic groove along the first direction.

The application provides a display unit and a display device. The display unit comprises a first substrate, a second substrate arranged opposite to the first substrate, a pixel wall arranged between the first substrate and the second substrate and surrounded by the first substrate and the second substrate to form an enclosed cavity, a light control plate comprising at least two blades rotatably connected in the enclosed cavity, a surface of the blade being provided with a reflection layer or a light absorption layer of a preset color, two blades of the at least two blades having opposite electric properties or opposite magnetic properties, and a driving electrode arranged at least in two of the first substrate, the second substrate and the pixel wall in a rotation direction of the blade, for driving the light control plate to rotate to a corresponding angle position to display a corresponding brightness. The display unit can avoid the problems of black spots appearing in white display of electrowetting display, splitting of ink shrinkage and coagulation of microcapsules into groups, and the response rate is improved.

The invention discloses a method for eliminating black spots induced by EBSD (electron back-scattered diffraction) metal sample electrolytic polishing preparation, which comprises the following steps: cutting and cleaning a sample: cutting the sample by using a wire cutting machine, putting the sample into an ultrasonic cleaning machine, cleaning, and blow-drying; rough grinding is conducted, specifically, a hardened layer generated by wire cutting is removed on a metallographic grinder through abrasive paper; fine grinding: sequentially carrying out wet grinding on the sample by adopting abrasive paper with different mesh numbers according to the mesh numbers from low to high, and covering scratches of the next grinding; first diamond polishing paste is evenly smeared, and polishing is conducted till only shallow scratches are left on the surface of the sample; fine polishing is conducted, specifically, second diamond polishing paste is evenly smeared till the second diamond polishing paste is in a mirror surface shape; absolute ethyl alcohol and perchloric acid are prepared into electrolyte according to the adding sequence, and finally electrolytic polishing is conducted; the method is simple and safe, can be used for preparing high-quality black-spot-free EBSD samples, is wide in application range, and can be suitable for preparing EBSD samples made of different metal materials.

The utility model provides an HSG product assembly detection automaton, which relates to the technical field of detection automaton, and comprises a support cabinet, the upper end of the support cabinet is fixedly provided with a placing table, the upper end of the placing table is provided with a first camera detection mechanism, and the upper end of the placing table is provided with a second camera detection mechanism. A third camera detection mechanism is arranged at the upper end of the placement table, the second camera detection mechanism is the same as the third camera detection mechanism, the first camera detection mechanism comprises a base, and a KK module is fixedly mounted at the upper end of the base; according to the utility model, whether the two openings of the white HSG are lack of glue or not and whether the surface has black spots or not can be detected, a to-be-provided sample is tested, meanwhile, a glue shell product can be conveniently detected, and a light source can be provided for the first camera detection module through the arrangement of the first light source module, so that the detection precision of the first camera detection module is improved.

Method for optimizing laser parameters for an ophthalmic laser (12) of a treatment device (10), wherein the method comprises the following steps performed by means of a control device (18): - Determine (S12) whether a treatment quality with the treatment device (10) performed with first laser parameters (S10) corresponds to a predetermined treatment quality criterion, wherein the laser parameters include at least a laser pulse energy, a spatial laser pulse spacing and a spatial laser pulse path spacing; - if the treatment quality does not meet the treatment quality criterion, provide a second laser parameter (S14) in which at least one laser parameter is adjusted by a predetermined value; - wherein the second laser parameters are used for subsequent treatment with the treatment device (10) (S16); - where the treatment quality criterion includes at least one of the following aspects: ◯ the formation of an opaque blister layer in a treatment area; ◯ the formation of black spots in the treatment area; ◯ a separation result, which is determined in particular by the required dissection time of irradiated tissue; ◯ a recovery outcome, determined in particular by an inflammatory response and / or achieved visual acuity; - wherein a grade is determined for the respective aspect of the treatment quality criterion, wherein the respective aspect is divided into a severe, medium and mild grade, wherein in a severe grade all three laser parameters are adjusted, wherein in a medium grade two laser parameters are adjusted, and wherein in a mild grade one of the laser parameters is adjusted.

The invention provides a folding screen and foldable electronic equipment, and relates to the technical field of electronic products. The folding screen comprises a screen body, a supporting piece is arranged on the back face of the screen body, and the supporting piece covers a bendable part of the screen body. The reinforcing piece is additionally arranged on the surface of the side, away from the screen body, of the supporting piece, or the structure of the supporting piece is improved, so that the structural strength of the foldable portion of the folding screen is enhanced. The supporting piece and the reinforcing piece are fixedly connected to the screen body, and the folding screen is of an integral structure. Therefore, the impact resistance of the folding screen can be improved, the failure problems of broken bright spots, black spots and the like of the folding screen are prevented, and the use effect of the folding screen is ensured. And moreover, the movement form of the folding screen is not influenced, and scratching abnormal sound is not generated, so that the use effect of the foldable electronic equipment can be improved. In addition, the folding screen is simple in structural design and convenient to assemble.

The invention provides a polaroid, a display module and a display device.The polaroid comprises a polarizing layer, a compensation layer and a first bonding layer, and the compensation layer is arranged on one side of the polarizing layer; the first bonding layer is arranged between the compensation layer and the polarization layer, the first bonding layer comprises a plurality of first bonding parts, and the first bonding parts comprise thermal expansion materials; wherein the first bonding parts extend in the first direction, the multiple first bonding parts are arranged at intervals in the second direction, and the first direction intersects with the second direction. According to the polaroid provided by the invention, the first bonding part formed by the thermal expansion material is arranged between the compensation layer and the polarizing layer, and the first bonding layer expands in the process of a high-temperature and high-humidity experiment, so that the overall shrinkage amount of the polaroid is reduced or the whole polaroid does not shrink. Besides, in the display module, the polaroid does not excessively pull the packaging layer at the boundary position, so that the packaging integrity of the packaging layer is ensured, water vapor is prevented from entering the packaging layer to form black spots, and the display performance is improved.

This invention provides a display panel, comprising: a display area, an aperture area, and an isolation area located between the display area and the aperture area. The isolation area is characterized by comprising: a substrate; an inorganic insulating layer on the substrate, the inorganic insulating layer having at least one recess; a light-emitting layer and a cathode located on the side of the inorganic insulating layer away from the substrate, wherein the light-emitting layer and the cathode are disconnected at the at least one recess in the inorganic insulating layer as they extend from the display area to the isolation area. The display panel provided by this invention, by providing a recess in the inorganic insulating layer of the isolation area, can isolate both the light-emitting layer and the cathode, preventing further corrosion of the light-emitting layer and cathode under the influence of water and oxygen, and also isolating the cathode signal to prevent the aggravation of black spot phenomena.

According to the dust removal device, a feeding opening is formed in a first box body, an electronic dust collection mechanism is arranged in the first box body, an air outlet is formed in a second box body, an air suction mechanism is arranged in the second box body, and the second box body is located above the first box body and communicates with the first box body; wherein the electronic dust collection mechanism comprises a metal part detachably installed in the first box body, an electrostatic generator arranged on the inner wall of the first box body and an electronic emitter arranged at the feeding port, the electrostatic generator is electrically connected with the metal part, and the electrostatic generator, the electronic emitter and the air suction mechanism are electrically connected with the control mechanism. Dust in front of the detection section of the black spot detector is effectively removed, so that the working precision of the black spot detector is improved, the reliability of product quality is improved, meanwhile, a worker can conveniently replace a metal part, and the working efficiency is improved.

The invention discloses a quality inspection production line for plastic package products, and relates to the technical field of industrial visual inspection.The quality inspection production line comprises a quality inspection table and further comprises an inspection assembly, a visual inspection mechanism and a pressing assembly.The inspection assembly comprises two pairs of L-shaped supports fixed to the two sides of the quality inspection table, and each pair of L-shaped supports is rotationally provided with a tensioning roller; the two tensioning rollers are sleeved with an inspection conveying belt, a plurality of containing sinking grooves are formed in the inspection conveying belt at equal intervals, and a through groove is formed in each containing sinking groove. The two visual inspection mechanisms are located above and below the inspection belt respectively, and the industrial camera assembly directly shoots the bottom face of a product through the inspection belt through groove; products are conveyed in the placing sinking groove of the inspection belt in a stepping mode, the upper camera and the lower camera shoot synchronously, and the control module compares double-face images (black spots, through printing and other defects) in real time. Through the design of the through groove, bottom shooting is not blocked, and the efficiency loss (a traditional production line needs to be shut down for turning over) and the product pollution risk caused by manual turning over are avoided.