Array type image detector

Abstract

The present application provides an array-type image detection device, comprising two rows of imaging arrays spaced apart along a first direction, each row of the imaging arrays comprising a plurality of imaging modules spaced apart along a second direction, each imaging module comprising a magnifying lens and an imaging chip arranged in sequence along its optical axis, each imaging module magnifies and captures an image to be detected located in its detection area within its imaging area, and acquires it by the imaging chip located in its imaging area, and each detection area, except for the detection areas located on both sides in the second direction, has a portion overlapping with another detection area at both ends along the second direction. The array-type image detection device provided by the present invention can effectively solve the problem that the resolution of the conventional contact image sensor is low, it is difficult to detect a high-resolution image, and there is a detection blind spot when performing magnification detection, and a clear magnified image of the image to be detected can be acquired within the full width range.

Description

[Technical field]

[0001] This application relates to the optical imaging technology field, and more particularly to array-based image sensing devices. [Background technology]

[0002] Image detection technology relates to many technical fields such as optical imaging, photoelectric conversion, signal processing, etc., and can be widely applied to industrial production and manufacturing processes, and realizes product quality detection by obtaining detailed features such as product surface and / or internal structure, texture, etc. Obviously, there are multiple orders of magnitude differences in size between the products to be detected and the image features to be identified, so it is necessary to determine image detection schemes with different detection accuracy / resolution for different products to be detected and detection scenes. In particular, when it is necessary to detect micron-level image features, defects, and flaws on the product surface, it is necessary to design a more specialized image detection scheme.

[0003] In the manufacturing process of lithium batteries, detecting micron-level burrs between the positive and negative electrode sheets and the separator is a typical image detection scene that requires obtaining the micron-level features of the product. With the expansion of China's new energy vehicle market, the demand for power lithium batteries has increased significantly. At the same time, the demand for lithium batteries is constantly increasing due to the rapid development of industries such as mobile phones, electric vehicles, power tools, and digital cameras. The rapid development of the lithium battery industry has already become a new investment focus in the manufacturing field. However, at the same time, various news about lithium battery fires and explosions are frequently published in media reports, making consumers hesitate to choose. Research has found that micron-level burrs, which can only be clearly seen under a microscope, between the positive and negative electrode sheets and the separator of lithium batteries are one of the main culprits that cause lithium battery explosions and fires. Whether it is hardware die cutting or laser cutting, it is difficult to avoid the occurrence of burrs in the above-mentioned areas, so comprehensive and accurate inspection of the above-mentioned micron-level burrs has become an important measure to ensure the safety of lithium battery products.

[0004] It is usually difficult to achieve ideal results when performing full-width real-time high-resolution detection of the above-mentioned micron-level image features using existing image detection means. For example, when using a CCD or CMOS camera to acquire images, the device volume is large and the scanning distance is long, so it is usually not suitable for installation and operation in an actual production line environment. Meanwhile, when using a conventional contact image sensor, there is a problem that high-resolution image detection cannot be accurately realized due to its low imaging resolution. Therefore, there is a strong demand for a technology that can effectively enlarge the image of the product waiting for inspection so as to realize accurate acquisition of high-resolution image features using a low-resolution chip, and ensure the short distance and full width of image detection so as to meet the needs of synchronous and comprehensive inspection in the production process. Summary of the Invention [Problem to be solved by the invention]

[0005] In order to solve the above-mentioned conventional technical problems, the present application aims to provide an array-type image detection device that realizes high-resolution, short-distance, full-width image detection using a low-resolution imaging chip. [Means for solving the problem]

[0006] The embodiments of the present application can be realized by the following technical solutions.

[0007] An array-type image detection device having two rows of imaging arrays spaced apart along a first direction, each row of the imaging array having a plurality of imaging modules arranged at intervals along a second direction, each imaging module having a magnifying lens and an imaging chip arranged in sequence along its optical axis, each imaging module magnifying and imaging an image to be detected located within its detection area within its imaging area, and acquiring the image by the imaging chip located within its imaging area, and each detection area, except for the detection areas located on both sides of the beginning and end in the second direction, has a portion at both ends along the second direction that overlaps with the other detection areas.

[0008] Furthermore, the magnifying lens is a meniscus lens having a concave entrance surface and a convex exit surface, the radius of the entrance surface is 15 mm or less, the radius of the exit surface is 8 mm or less, and the distance between the intersections of the entrance and exit surfaces with the optical axis is 3 mm or less.

[0009] Preferably, the magnifying lens is further cut along its optical axis so that its projection onto a plane perpendicular to the optical axis forms a rectangle, the length of which is in the range of 9 to 11 mm and the width of which is in the range of 2 to 6 mm.

[0010] Preferably, the distance from the detection region to the imaging region of each imaging module is 90 mm or less, and the image magnification is 1 to 6 times.

[0011] Furthermore, of the two rows of imaging arrays, each imaging module of one row of imaging arrays has a first optical axis in the same direction, and each imaging module of the other row of imaging arrays has a second optical axis in the same direction, and both the first optical axis and the second optical axis are perpendicular to the second direction.

[0012] Preferably, the range of the angle between the first optical axis and the second optical axis is 8° or more and 12° or less, and the bisector of the angle extends along a third direction that is perpendicular to the first direction and the second direction.

[0013] Preferably, the detection regions of each imaging module are at the same height in the third direction.

[0014] Additionally, each imaging module further includes an aperture stop located on its optical axis, the aperture stop being located between the detection area of ​​the imaging module and the magnifying lens.

[0015] Preferably, the distance from the aperture stop of each imaging module to the detection region is 25 mm or less.

[0016] Preferably, the imaging plane of each imaging chip is perpendicular to the optical axis of the imaging module in which it is located.

[0017] Preferably, the array type image detection device further includes a hollow outer frame for fixedly housing each of the imaging modules.

[0018] Preferably, the array type image detection device further comprises a light-opaque baffle located between the two imaging arrays.

[0019] Preferably, the array type image detection device further comprises a light source module for generating a light beam toward the detection area.

[0020] Preferably, the array type image detection device comprises: The imaging device further includes a data conversion module for converting an analog signal acquired by each imaging chip into a digital signal, and a data processing module for processing the digital signal and generating a digitized enlarged image of the image to be detected. Effect of the Invention

[0021] The array-type image detection device provided by the embodiments of the present application achieves miniaturization of the device while satisfying close-range magnification imaging through the design of the magnifying lens and the structural parameters of the magnifying lens installed in each imaging module, and solves the problem that the installation space of the device is too large, thereby realizing the need to use a low-resolution imaging chip to scan a high-resolution object surface at a close distance.

[0022] At the same time, the two rows of imaging arrays are arranged with a staggered interval, so that the detection areas are overlapped with each other along the scanning direction, and the optical axes of the two rows of imaging arrays are preferably at a certain angle, which can effectively solve the problem that a single row of imaging array has a detection blind spot during enlarged detection, and ensure that the scanning information of the entire width of the image to be detected can be read within a certain error range. [Brief description of the drawings]

[0023] [Figure 1] FIG. 2 is a schematic diagram of the structure of a lithium battery film. [Diagram 2] FIG. 1 is a schematic diagram of an array-type image sensing device integrated into an existing production line environment. [Diagram 3] 1 is a side cross-sectional view along a first direction of an array-type image detection device according to one embodiment of the present application. [Figure 4] 1 is a side cross-sectional view along a second direction of one row of an imaging array of an array-type image detection device according to one embodiment of the present application. FIG. [Figure 5a] FIG. 2 is a schematic three-dimensional diagram of one magnifying lens of an array-type image detection device according to one embodiment of the present application. [Figure 5b] 5b is a side cross-sectional view of the magnifying lens shown in FIG. 5a. [Figure 5c]FIG. 5b is a top view of the magnifying lens shown in FIG. 5a. [Figure 6] FIG. 2 is a diagram showing the optical path of one magnifying lens of an array-type image detection device according to one embodiment of the present application. [Figure 7] FIG. 2 is a top view of a plurality of first imaging areas and a second imaging area of ​​an array-type image detection device according to one embodiment of the present application. [Figure 8] 8 is a top view of a plurality of first detection regions and second detection regions corresponding to FIG. 7. FIG. [Figure 9] 4 is a side cross-sectional view of an array-type image detection device according to another embodiment of the present invention taken along a first direction. FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0024] In the following, the present application will be further described based on preferred embodiments and with reference to the accompanying drawings.

[0025] In addition, the various components in the drawings are enlarged or reduced in size for ease of understanding, but such an approach is not intended to limit the scope of protection of the present application.

[0026] Words in the singular include the plural and vice versa.

[0027] In addition, in the description of the embodiments of the present application, if the orientation or positional relationship indicated by the terms "upper", "lower", "inner", "outer" and the like is based on the drawings, or if the orientation or positional relationship is always placed when the product according to the embodiments of the present application is used, it is merely for the ease and simplification of the description of the present application, and does not indicate or imply that the device or element referred to has a specific orientation, must be configured and operated in a specific orientation, and therefore cannot be understood as a limitation of the present application. In addition, in the description of the present application, the term "first", "second", etc. are used in this specification to distinguish different units, but these are not limited to the order of manufacture, and cannot be understood as indicating or implying relative importance, and the names may be different in the detailed description of the present application and the claims.

[0028] The terms used in this specification are used to describe the embodiments of the present application, but are not intended to limit the present application. Furthermore, unless otherwise clearly defined and limited, the terms "set", "connected", and "connected" should be understood in a broad sense, for example, fixed connection, detachable connection, integral connection, mechanical connection, direct connection, indirect connection via an intermediate medium, or internal communication between two elements. The specific meanings of the above terms in this application can be specifically understood by those skilled in the art.

[0029] In order to more clearly explain the technical solution of the present application, the technical difficulties faced in real-time detection of micrometer-level image features in current production manufacturing processes will be described in detail first.

[0030] FIG. 1 shows a schematic diagram of the battery film structure of a lithium battery. As shown in FIG. 1, the battery film includes a core 700 made of a material such as copper or aluminum, and coatings 701 and 702 applied to both sides of the core 700. Generally, the thickness of the core 700 and the coatings 701 and 702 is about several tens of um. In the manufacturing and cutting process of the battery film, various burrs 703 often appear on the surface of the core and the coating, and these burrs 703 cause minute defects on the surface of the battery film, greatly increasing the probability of the lithium battery leaking, exploding, and other dangers. Therefore, in the manufacturing process of the battery film, it is an essential process to detect the presence of the burrs 703.

[0031] By using a device such as a microscope to statistically analyze the size of the above-mentioned burrs 703, it is found that the size is generally about 20 um, and the burrs 703 may appear at various positions on the battery film. Therefore, it is determined that it is necessary to realize real-time detection of micron-level image features within a range equivalent to the entire width of the battery film without affecting the normal operation of the production line.

[0032] One optional image detection scheme is to use a linear scan camera (e.g., a CCD or CMOS camera) to continuously scan and detect the product. However, although a linear scan camera can achieve high-resolution dynamic scanning, its volume is generally large and the scanning distance is long, and it is often not possible to install it due to device space restrictions. At the same time, if the scanning distance is too long, the cost of the hardware device will increase rapidly to meet the performance indicators required to detect micron-level burrs mentioned above.

[0033] Another optional scheme is to use a CIS (Contact Image Sensor) or CIS array to dynamically scan the battery film at close range. CIS is a common sensor used for image acquisition / collection. It uses multiple photosensitive elements arranged in an array and corresponding photoelectric conversion chips to convert the optical signal of the image into an electrical signal. Its small size and high integration make it especially suitable for collecting and acquiring product images in various production line environments.

[0034] FIG. 2 shows the arrangement of an image detection device integrated into a production line environment and an image detection scheme. As shown in FIG. 2, the surface of the object 900 to be detected has a certain width size along the Y direction (usually referred to as the scanning direction), and under normal operating conditions of the production line, it moves continuously along the X direction (usually referred to as the scanning sub-direction). This image detection device has a plurality of CIS sensors 800 spaced apart along the Y direction (usually, the number of CIS sensors 800 needs to be determined according to the size of the object 900 to be detected so as to cover the entire width), and each CIS sensor 800 has a photoelectric conversion chip consisting of an array of linearly spaced photosensitive elements 811 for converting light emitted from the surface of the object 900 to be detected into an analog signal (electrical signal), and obviously, the number of photosensitive elements 811 contained per unit length is the resolution of the CIS sensor (in DPI units), and the above-mentioned photoelectric conversion chip is generally mounted on a photoelectric conversion chip substrate 810, and the CIS sensor generally further has a structure such as an interface circuit that serially outputs the analog signal after photoelectric conversion.

[0035] Once such an arrangement is completed, different areas passing through the image detection device can be scanned continuously and full-width at regular time intervals while the object 900 waiting to be detected continues to move, and one row of image signals photoelectrically converted by each photosensitive element 811 can be obtained for each scan, and a two-dimensional detection image of the object 900 waiting to be detected can be obtained by joining multiple rows of image signals obtained by multiple scans.

[0036] Although the above-mentioned image detection device can perform image detection of objects of conventional sizes waiting to be detected, it is difficult to directly apply it to the detection of micron-level burr images of battery film, because the imaging resolution of conventional contact image sensors is low, and for example, a CIS sensor with a resolution of 1200 DPI has a pixel dot size of 25.4 mm / 1200 ≒ 21 μm, that is, the minimum resolution of its imaging surface is 21 μm. Obviously, for burrs of about 20 μm, the above-mentioned standard contact image sensor alone cannot clearly image and recognize them, and its structure needs to be improved to meet the needs of high-resolution image recognition.

[0037] However, the simple use of a single magnifying lens cannot simultaneously meet the needs for clear imaging covering the entire detection width and close-range contact detection; therefore, it is necessary to rationally design the optical path of the image magnifying section and its cooperative relationship with the imaging section in combination with the actual production line environment and the characteristics of the selected image sensor, thereby realizing close-range, full-width detection of micron-level image features.

[0038] In order to achieve the above object, the present application provides, by way of an embodiment, an array-type image detection device, comprising two rows of imaging arrays spaced apart along a first direction, each row of the imaging array comprising a plurality of imaging modules arranged at intervals along a second direction, each imaging module comprising a magnifying lens and an imaging chip arranged in sequence along its optical axis, each imaging module magnifying and imaging an image to be detected located within its detection area within its imaging area, and acquiring the image by the imaging chip located within its imaging area, and each detection area, except for the detection areas located on both the front and rear sides in the second direction, has portions at both ends along the second direction that overlap with other detection areas.

[0039] The array-type image detection device provided in the embodiment of the present application has two imaging arrays arranged at a predetermined interval in a first direction, each imaging array has a plurality of magnified imaging modules arranged at intervals along a second direction, and the detection areas of the two imaging arrays are arranged to overlap along the second direction. The arrangement of the two imaging arrays at intervals allows the detection areas to cover the entire width in the second direction, thereby ensuring that the images within the coverage range of the detection areas are clearly magnified and captured without omission.

[0040] The array-type image sensing device provided by the present application will be described in detail below with reference to specific embodiments.

[0041] [Example 1] FIG. 3 shows a side cross-sectional view along the X-axis direction of an array-type image detection device according to a preferred embodiment 1 of the present invention. As shown in FIG. 3, the array-type image detection device has a first imaging array 1 and a second imaging array 2 arranged at a predetermined interval along a first direction (shown by the X-axis in FIG. 3).

[0042] FIG. 4 further illustrates a side cross-sectional view of the first imaging array 1 along a second direction (indicated by the Y-axis in FIG. 4, the Y-axis being in a different direction from the X-axis, and preferably the Y-axis being perpendicular to the X-axis). As shown in FIG. 3 and FIG. 4, the first imaging array 1 includes a plurality of first imaging modules 10 arranged at intervals of a length H along the Y-axis direction. The Y-axis direction is generally called the scanning direction, and it is clear that the number of the first imaging modules 10 can be determined according to the length along the scanning direction in which each first imaging module 10 can perform effective detection and the overall length along the scanning direction in which detection is required, in order to ensure that the entire detection width is covered. Note that the interval H between each first imaging module 10 in the figure is merely a schematic preferred setting method, and does not limit the technical solution of the present application.

[0043] In addition, the array type image detection device further includes a hollow outer frame 31 for fixedly accommodating each of the above-mentioned imaging modules, and the outer frame 31 may adopt a metal aluminum material to further enhance the stability of the structure. Each of the above-mentioned imaging modules is fixed inside the outer frame 31 according to the respective optical path parameters by gluing, insertion, etc., while the inner wall of the outer frame 31 is coated with a black oxide coating, which can effectively eliminate the influence of stray light on image detection.

[0044] In this embodiment, preferably, as shown in Fig. 3, the array type image detection device further includes a light source module 4, which emits light toward the detection area, and increases the light from the object surface in the detection area, which is advantageous for the subsequent image detection. The light source module 4 is a linear light source whose effective light-emitting area extends along the Y-axis direction to cover the entire width to be detected. A light source chip 43 is mounted on the light source substrate 42.

[0045] 3, the light source board 42 is preferably made of aluminum to improve the heat dissipation effect, and is further provided with a light scattering film 41 to achieve the effect of making the light uniform. To further improve the lighting effect, the number of light source modules 4 may be two or more, and a method of illuminating the light sources on both sides may be adopted.

[0046] In this embodiment, the array-type image detection device preferably further includes a data conversion module for converting the analog signal acquired by the imaging chip in each imaging module into a digital signal. Specifically, as shown in Fig. 3, the data conversion module includes a relay board 51 and a data transmission and conversion circuit (not shown) mounted thereon. Data transfer between the relay board 51 and each imaging chip is realized through a corresponding signal interface, that is, the pads of the relay board 51 and the back pads of the imaging chip are soldered by a process such as pin or reflow soldering to realize data transfer.

[0047] In this embodiment, preferably, the array type image detection device further includes a data processing module, specifically, as shown in FIG. 3, the data processing module includes a data processing board 52 equipped with a data processing chip 602 and a serial port circuit 604. The data processing chip 602 has an image pre-processing function, processes the digital signal received from the data conversion module, synthesizes it into a detection image, and transmits it to the external display module PC side through the serial port circuit 604 to complete the full-width display of the image. Those skilled in the art can select appropriate data chips and serial circuit boards according to specific needs, such as FPGA chips and CAMRALINK serial circuit boards, or other selectable data chips and serial circuits.

[0048] In addition, the data processing chip 602 controls the timing period by setting an internal register to realize control of the light source module 4, thereby achieving the purpose of synchronizing the light emission frequency of the light source module 4 and the scanning frame rate of each imaging module within the scanning period.

[0049] 3, the array-type image detection device further includes a second outer frame 32, the data conversion module is fixedly accommodated inside the outer frame 31, the data processing module is fixedly accommodated inside the second outer frame 32, and the second outer frame 32 and the outer frame 31 are fixedly connected by insertion, adhesion, integral molding or any other suitable method. The digital signal output from the data conversion module is connected through the socket 601 and the socket 603 of the data processing module to realize signal conversion and transmission.

[0050] Preferably, a heat sink 33 is further provided on the opposite side of the second outer frame 32 to the outer frame 31, and the heat sink 33 is preferably made of a material with excellent heat dissipation properties, such as metal, in order to dissipate heat generated during operation of the data processing chip 602.

[0051] The overall configuration of the array type image detection device of this embodiment has been described above. Next, the operating principle of this array type image detection device will be described in detail.

[0052] Still taking the first imaging array 1 as an example, as shown in Figures 3 and 4, each first imaging module 10 in the first imaging array 1 includes a first magnifying lens 11 and a first imaging chip 12 arranged in sequence along its optical axis (shown as a first optical axis 14).

[0053] Furthermore, due to the magnifying action of the first magnifying lens 11, each first imaging module 10 has a first detection area 16 and a first imaging area 15 on both sides of the first magnifying lens 11, and an image awaiting detection located in the first detection area 16 can be magnified and imaged in the first imaging area 15 and acquired by the first imaging chip 12 located in the first imaging area 15.

[0054] 5a to 5c show a perspective view, a side cross-sectional view, and a top view, respectively, of a first magnifying lens 11 included in the first imaging module 10 in some preferred embodiments. As shown in Fig. 5a, the first magnifying lens 11 is preferably made of a meniscus lens, with an entrance surface 11A facing the object side, which is a concave surface and exerts a certain converging effect on light, and an exit surface 11B facing the image side, which is a convex surface and exerts a certain diverging effect on light.

[0055] Those skilled in the art know that the object distance, image distance and magnification of the lens can be determined by designing the radius of the incident surface, the exit surface and the pitch of the incident surface and the exit surface. In this embodiment, preferably, as shown in FIG. 5b, the radius of the incident surface 11A is R11A≦15 mm, the radius of the exit surface 11B is R11B≦8 mm, and the distance between the intersection of the incident surface 11A and the exit surface 11B with the first optical axis 14 is H11≦3 mm. By setting the above-mentioned preferred configuration parameters, under the condition that the distance between the first detection area 16 and the first imaging area 15 is 90 mm or less, the image to be detected can be enlarged by 1 to 6 times, thereby realizing the enlarged detection of the image to be detected while satisfying the miniaturization of the device.

[0056] In this embodiment, the first magnifying lens 11 is preferably made of a material such as glass having good optical properties and high workability. Furthermore, by applying a process such as plating to the lens, it is possible to reduce reflected light on the lens surface and improve light transmittance. In order to facilitate the attachment of the lens and to miniaturize the device, the lens may be cut into a long shape around the optical axis of the lens as shown in Figures 5a and 5c. Preferably, the first magnifying lens 11 after cutting has a length of 9-11 mm along the Y-axis direction and a width of 2-6 mm along the X-axis direction.

[0057] In this embodiment, the first imaging chip 12 optionally included in the first imaging module 10 is the above-mentioned linear CIS sensor, specifically including a first chip substrate 122 on which a first photoelectric conversion chip 121 is mounted, and corresponding connecting lines and interface circuits (not shown). In addition, in some other embodiments, other sensors having image scanning functions may be selected according to the actual needs of image detection.

[0058] In this embodiment, as shown in FIG. 3, preferably, the first imaging module 10 further includes a first aperture stop 13 arranged along the first optical axis 14, and the first magnifying lens 11 is located between the first aperture stop 13 and the first imaging chip 12. By using the first aperture stop 13, it is possible to block light rays of the light beam that are relatively deviated from the first optical axis 14, which directly affects the clarity, accuracy, brightness, depth of field, etc. of the image. The first aperture stop 13 has a circular hole structure with a hole diameter of 1.4 mm to 1.6 mm, and may be formed by drilling a hole in the middle of the light-shielding paper, or may be directly processed by drilling a hole at the intersection position of the outer frame 31 and the first optical axis 14.

[0059] Preferably, the working distance from the first aperture stop 13 to the first detection area 15 is ≦25 mm, which can achieve the effect of close-range scanning imaging, is advantageous for miniaturizing the device, and solves the problem of device installation space.

[0060] FIG. 6 further shows a half-field optical path diagram of the first imaging module 10. As shown in FIG. 6, based on the specific needs of close-range magnification imaging, the size parameters of the first magnifying lens 11, including the radius of the entrance surface and the exit surface and the distance of the intersection of the entrance surface / exit surface and the first optical axis, can be designed to determine the magnification ratio of the first magnifying lens 11 and the object distance and image distance to be clearly imaged. At the same time, the first aperture stop 13 and the outer frame are aligned to restrict the light beam deviated from the first optical axis 14, thereby forming a first detection area 16 and a first imaging area 15 on both sides of the first optical axis 14, which can magnify and image the image to be detected located in the first detection area 16, respectively. The first imaging area 15 and the first detection area 16 have lengths L' and L respectively along the Y-axis direction, where L' / L is the magnification ratio of the first magnifying lens 11.

[0061] As shown in FIG. 6, the enlarged image to be detected is an inverted real image, and further signal inversion and other operations must be performed in the subsequent image processing.

[0062] In an actual image detection process, an object 900 to be detected (the above-mentioned battery film) is placed in the first detection area 16, and the first imaging chip 12 is placed in the first imaging area 15. In general, the first imaging module 10 realizes image acquisition by the first imaging chip 12, so that the effective scanning length of the first imaging chip 12 can be considered to be equal to L'. At this time, an image of the surface of the object to be detected (image to be detected) can be enlarged and clearly captured in the first imaging area 15 and acquired by the first imaging chip 12.

[0063] In the following Table 1, one set of preferred design parameters of the first imaging module 10 is diagrammatically shown, and it is obvious that those skilled in the art can determine the corresponding design parameters based on the actual image detection indicators.

[0064] [Table 1] The configuration of the first imaging module 10 and the magnification imaging principle have been described in detail above. Furthermore, a plurality of first imaging modules 10 are arranged at intervals along the Y-axis direction with a pitch H, i.e., a first imaging array 1 is formed.

[0065] The above-mentioned first imaging array 1 uses a plurality of magnifying lenses arranged at intervals and imaging chips corresponding to them one-to-one, and can effectively shorten the object-image distance and realize short-distance scanning and device miniaturization under the premise of securing a specific magnification and wide-width scanning, and therefore can effectively eliminate the disadvantage that the object-image distance must be increased to cover a relatively large image detection area and avoid imaging distortion when a single magnifying lens is used, resulting in a significant increase in device size. However, when a single imaging array with one row is used, there still exists a problem of missed detection of a specific area in the entire detection width, and the reason for this can be explained by FIG. 4.

[0066] As shown in Figure 4, in the multiple first imaging modules 10 of the first imaging array 1, each first imaging area 15 expands the first detection area 16 along the Y direction, so that even if each first imaging chip 12 is connected to each other as closely as possible so that each first imaging area 15 is connected coherently, each corresponding first detection area 16 still has multiple detection blind spots along the Y direction, and the length of each detection blind spot is HL. The existence of the above-mentioned detection blind spots is determined by the characteristics of the multiple expanded optical path structures themselves arranged at intervals, and causes a detection miss phenomenon on the surface of the object waiting to be detected, so further improvement of the single-row expanded imaging method is required.

[0067] For this reason, as shown in Fig. 3, in addition to the first imaging array 1, in this embodiment, a second imaging array 2 is further provided at a certain interval from the first imaging array 1 along the X-axis direction. Specifically, the second imaging array 2 includes a plurality of second imaging modules 20 arranged at intervals along the Y-axis direction, and each second imaging module 20 includes a second magnifying lens 21 and a second imaging chip 22 arranged in sequence along its optical axis (shown as a second optical axis 24). Accordingly, a second detection region 26 and a second imaging region 25 for magnified imaging are formed on both sides of the second optical axis 24, respectively, and the second imaging chip 22 is placed within the second imaging region 25.

[0068] The second imaging module 20 may include a second aperture stop 23, similar to the first imaging module 10, and the second imaging chip 22 includes a second chip substrate 222 and a second photoelectric conversion chip 221 mounted thereon.

[0069] In some preferred embodiments, the configuration parameters of each first imaging module 10 included in the first imaging array 1 and each second imaging module 20 included in the second imaging array 2 are the same, i.e., completely identical imaging modules may be used, and at the same time, the pitch along the Y-axis direction of each second imaging module 20 is the same as the pitch along the Y-axis direction of each first imaging module 10 (both indicated by H), so Figure 4 can also be used to explain the configuration of the second imaging array 2, and for the sake of brevity, the description will not be repeated here.

[0070] In this embodiment, preferably, as shown in FIG. 3, the first detection area 16 and the second detection area 26 are at the same height in the Z-axis direction, and the Z-axis is perpendicular to the X-axis and the Y-axis.

[0071] Figure 7 shows a top view of multiple first imaging areas 15 and second imaging areas 25 in this preferred embodiment (the figure shows three first imaging areas 15 and three second imaging areas 25 diagrammatically), each of the first imaging chip 12 and second imaging chip 22 being located within each of the imaging areas mentioned above, and Figure 8 is a top view of multiple first detection areas 16 and second detection areas 26 corresponding to Figure 7. 3, 4, 7 and 8, in a preferred embodiment of the present application, the first imaging module 10 and the second imaging module 20 are arranged in a staggered manner along the Y-axis direction, and the arrangement is designed to satisfy that, except for the first detection area 16 and / or the second detection area 26 located at the front and rear ends in the Y-axis direction, each of the first detection areas 16 has a portion overlapping the second detection area 26 along the Y-axis direction at both ends, and each of the second detection areas 26 has a portion overlapping the first detection area 16 along the Y-axis direction at both ends. With the above-mentioned settings, the first imaging array 1 and the second imaging array 2 realize coverage of the entire detection area without blind spots, thereby realizing full-width expanded detection of image features at the micrometer level.

[0072] In this embodiment, preferably, as shown in FIG. 7, the center of each first imaging area 15 is aligned exactly with the midpoint of the line connecting the centers of two adjacent second imaging areas 25, and correspondingly, as shown in FIG. 8, the center of each first detection area 16 is aligned exactly with the midpoint of the line connecting the centers of two adjacent second detection areas 26, and both ends of each first detection area 16 each have an overlapping portion of ΔZ with two adjacent second detection areas 26, which is similar for the second imaging area 25 and the second detection area 26, and will not be repeated here.

[0073] Specifically, taking the parameters shown in Table 1 as an example, it is preferable to design the above-mentioned first imaging module 10 and second imaging module 20 with H set to 21 mm, and therefore ΔZ=0.5 mm.

[0074] In addition, those skilled in the art can flexibly adjust the pitch, staggered arrangement method, size of overlapping portion, etc. of each imaging module in the first imaging array 1 and the second imaging array 2 to meet actual image detection needs, and none of the above-mentioned adjustments deviate from the technical idea of ​​the present application.

[0075] As shown in FIG. 3, preferably, the direction of the first optical axis 14 of each first imaging module 10 is the same, the direction of the second optical axis 24 of each second imaging module 20 is the same, both the first optical axis 14 and the second optical axis 24 are perpendicular to the Y-axis direction, and the bisector of the angle θ between the first optical axis 14 and the second optical axis 24 points in the Z-axis direction.

[0076] In this embodiment, the preferred value range of θ is 8° to 12°, and as shown in FIG. 3 and FIG. 8, when the depth of field of each magnifying lens is Δl, according to the sine law, the effective width of each detection area in the scanning sub-direction, i.e., in the X direction, is ΔD=4Δl*Sin(θ / 2). The effective width represents the allowable tolerance range ΔD of the detection area in the X direction, that is, within this depth of field tolerance range, a clear image can be scanned. The object to be detected within the above-mentioned ΔD range continues to move along the X direction and is continuously scanned, and the optical signal of its surface is acquired by the first imaging array 1 and the second imaging array 2 and converted into an electrical signal, and then undergoes analog-to-digital conversion through the data conversion module, and finally synthesized into a surface image by the data processing module. Specifically, the processing procedures of the data processing module include signal inversion, position calibration, overlap removal, image splicing, compensation synthesis, etc. The above operations are already known to those skilled in the art.

[0077] When the first imaging array 1 and the second imaging array 2 are close to each other in the X direction, the optical paths of those imaging modules may affect each other. This is because when a light ray enters the magnifying lens on one side, it is usually irradiated to the imaging chips located on each side, but because the exit surface of the magnifying lens has a convex structure, the light is emitted diverging at a certain angle, and at the same time, because the distance between the imaging chips on both sides is small, the light ray on one side enters the imaging chip on the other side, causing interference.

[0078] Therefore, as shown in Fig. 3, the array-type image detection device preferably further includes a baffle 34. In this embodiment, the baffle 34 is located between the first imaging array 1 and the second imaging array 2, extends parallel to the Z axis and along the Y axis, and is fixedly connected to the outer frame 31 by means of insertion, adhesion, etc., and serves to separate the magnifying lenses and the imaging chips on both sides. Preferably, the baffle 34 is made of black PC material or other material with relatively high light absorption, so as to absorb stray light caused by wall reflection, further increase the effective optical signal, and present a clearer image.

[0079] [Example 2] FIG. 9 shows a side cross-sectional view along the X-axis direction of an array-type image detection device according to a preferred embodiment 2 of the present invention, which differs from embodiment 1 in that the first imaging chip 12 and the second imaging chip 22 also rotate correspondingly with respect to the first optical axis 14 and the second optical axis 24, respectively, and the imaging surfaces of each imaging chip are set to be perpendicular to the optical axis of the imaging module in which they are located.

[0080] Specifically, as shown in FIG. 9, by rotating the first chip substrate 122 so that its surface is perpendicular to the first optical axis 14 and aligning the first optical axis 14 with the center of the first photoelectric conversion chip 121, the imaging surface of the first imaging chip 12 becomes perpendicular to the first optical axis 14, and at the same time, the chief ray also passes exactly through the center of the first magnifying lens 11 and can be irradiated to the center of the first photoelectric conversion chip 121, which makes it more advantageous to realize optical symmetry and can tolerate a wider range of scanning deviations.

[0081] Similar operations can be performed for the second imaging chip 22, and will not be described again here.

[0082] 9, in this embodiment, the first photoelectric conversion chip 121 and the second photoelectric conversion chip 221 convert the optical signal of the image to be detected into an analog signal, and then connect to the corresponding socket 605 provided on the relay substrate 51 via the socket 600 provided on the first chip substrate 122 and the second chip substrate 222, respectively, and the connection method may be a method such as an FFC cable. In this way, data transfer between the imaging chip and the data conversion module is realized.

[0083] Although the specific embodiments of the present application have been described in detail above, those skilled in the art may further make some improvements and modifications to the present application without departing from the principles of the present application, and these improvements and modifications also fall within the scope of the claims of the present application. [Explanation of symbols]

[0084] 1: First imaging array 10: First imaging module 11: First magnifying lens 11A:Incidence surface 11B: Output surface 12: First imaging chip 121: First photoelectric conversion chip 122: First chip substrate 13: First aperture stop 14: First optical axis 15: First imaging area 16: First detection area 2: Second imaging array 20: Second imaging module 21: Second magnifying lens 22: Second imaging chip 221: Second photoelectric conversion chip 222: Second chip substrate 23: Second aperture stop 24: Second optical axis 25: Second imaging area 26: Second detection area 31: Outer frame 32: Second outer frame 33: Heat sink 34: Baffle 4: Light source module 41: Light scattering film 42: Light source board 43: Light source chip 51: Relay board 52: Data processing board 600:Socket 601: Socket 602: Data processing chip 603: Socket 604: Serial port circuit 605: Socket 700: Core material 701: Coating 702: Coating 703: Bali 800: CIS sensor 810: Photoelectric conversion chip substrate 811: Photosensitive element 900: Object waiting to be detected

Claims

1. 1. An array-type image detection device comprising two rows of imaging arrays spaced apart along a first direction, Each column of the imaging array includes a plurality of imaging modules arranged at intervals along the second direction, each imaging module including a magnifying lens and an imaging chip arranged in sequence along its optical axis; Each imaging module enlarges and captures the image to be detected that is located within the detection area within the imaging area, and acquires it using an imaging chip located within the imaging area. Each detection area, except for the detection areas located at both ends in the second direction, has an overlapping portion with another detection area at both ends along the second direction. Array type image detection device.

2. the magnifying lens is a meniscus lens having a concave entrance surface and a convex exit surface, The radius of the entrance surface is 15 mm or less, and the radius of the exit surface is 8 mm or less; The distance between the intersections of the entrance surface and the exit surface with the optical axis is 3 mm or less.

2. The array-type image sensing device of claim 1.

3. The magnifying lens is further cut along its optical axis, and when projected onto a plane perpendicular to the optical axis, the resulting rectangle has a length in the range of 9 to 11 mm and a width in the range of 2 to 6 mm.

2. The array-type image sensing device of claim 1.

4. The distance from the detection region to the imaging region of each imaging module is 90 mm or less, and the image magnification is 1 to 6 times.

2. The array-type image sensing device of claim 1.

5. Among the two columns of the imaging arrays, each imaging module of the imaging array in one column has a first optical axis in the same direction, and each imaging module of the imaging array in the other column has a second optical axis in the same direction, and both the first optical axis and the second optical axis are perpendicular to the second direction.

2. The array-type image sensing device of claim 1.

6. an angle between the first optical axis and the second optical axis is in the range of 8° to 12°, and a bisector of the angle extends along a third direction perpendicular to the first direction and the second direction; 6. The array image sensing device of claim 5.

7. The detection regions of the imaging modules are at the same height in the third direction.

7. The array type image sensing device according to claim 6.

8. Each imaging module further includes an aperture stop located on its optical axis, the aperture stop being located between a detection region of the imaging module and a magnifying lens.

2. The array-type image sensing device of claim 1.

9. The distance from the aperture stop of each imaging module to the detection area is 25 mm or less.

9. The array-type image sensing device of claim 8.

10. The imaging surface of each imaging chip is perpendicular to the optical axis of the imaging module in which it is located.

2. The array-type image sensing device of claim 1.

11. The array type image detection device further includes a hollow outer frame that fixedly houses each of the imaging modules.

2. The array-type image sensing device of claim 1.

12. the array-type image detection device further comprises a light-opaque baffle positioned between the two imaging arrays; 2. The array-type image sensing device of claim 1.

13. The array type image detection device further includes a light source module for generating a light beam toward the detection area.

2. The array-type image sensing device of claim 1.

14. a data conversion module for converting analog signals acquired by each imaging chip into digital signals; a data processing module for processing the digital signal to generate a digitized enlarged image of the image to be detected.

2. The array-type image sensing device of claim 1.

Images