A code reading device for two-dimensional code in transparent medium

Abstract

The present application relates to the technical field of two-dimensional code recognition, and discloses a device for reading a two-dimensional code in a transparent medium, comprising an image capturing mechanism, the image capturing mechanism comprising a camera and a lens, the camera being arranged in the forward direction of the two-dimensional code, and the lens being arranged on the camera; an illumination mechanism, the illumination mechanism comprising a light source, the light source being a highly directional polarized backlight, the light source being arranged in the reverse direction of the two-dimensional code, and the light-emitting side of the light source facing the two-dimensional code; and an image processing system, the image processing system being electrically connected to the camera, and the image processing system being used to process and analyze the image captured by the camera. The device for reading a two-dimensional code in a transparent medium, by respectively arranging the camera and the light source on both sides of the two-dimensional code, makes the part where the light source irradiates the transparent medium form a bright area, and the part where the light source irradiates the two-dimensional code form a dark area, which not only increases the contrast of the two-dimensional code, but also increases the depth range in which the depth system can clearly read the two-dimensional code, and enhances the compatibility with the ups and downs of the material.

Description

Technical Field

[0001] The present application relates to the technical field of two-dimensional code recognition, and in particular to a device for reading a two-dimensional code in a transparent medium. Background Art

[0002] With the development of Industry 4.0, the demand for product traceability is increasing. Product traceability is to use the Internet of Things, automatic identification and other technologies, through professional instruments and devices, to customize unique identification information for each product as an anti-counterfeiting ID card, so as to collect, track and analyze data in various links such as product production, warehousing, logistics and sales, build a full life cycle management model for products, and effectively improve product quality and safety assurance levels.

[0003] However, for the 2D code in the transparent medium, the transparent medium is usually large (more than 150mm), but the 2D code in the medium is often very small (less than 1mm). In order to ensure that the code point system can read the code clearly, the imaging magnification of the code reading system is very high, resulting in a very small depth of field of the code reading system. When the material is placed up and down and the device fluctuates, it will exceed the depth of field range, resulting in blurred imaging of the code reading system, image reading failure, and then a decrease in the code reading rate. Summary of the invention

[0004] In view of the deficiencies in the prior art, the present application provides a code reading device for a two-dimensional code in a transparent medium, which solves the problem that it is difficult for a code reading device to read a two-dimensional code in a transparent medium.

[0005] To achieve the above-mentioned purpose, the present application provides the following technical solution: a device for reading a two-dimensional code in a transparent medium, comprising:

[0006] An image shooting mechanism, the image shooting mechanism comprising a camera and a lens, the camera is arranged in the front direction of the QR code, and the lens is arranged on the camera;

[0007] An illumination mechanism, the illumination mechanism comprising a light source, the light source being arranged in the opposite direction of the two-dimensional code, with a light emitting side of the light source facing the two-dimensional code;

[0008] An image processing system is electrically connected to the camera, and is used to process and analyze images taken by the camera.

[0009] Preferably, the image capturing mechanism further comprises a polarizing plate, and the polarizing plate is arranged on a side of the lens away from the camera.

[0010] Preferably, the image capturing mechanism further includes a polarized light detector, which is disposed on a side of the lens away from the camera, and the lighting mechanism further includes a polarizer, which is disposed on a light emitting side of the light source.

[0011] Preferably, the shooting direction of the camera is perpendicular to the surface of the QR code.

[0012] Preferably, the lighting direction of the light source is perpendicular to the back of the QR code.

[0013] Preferably, the light source includes a laser, a collimator, a semi-transparent and semi-reflective prism and a light intensity detection module, the collimator is arranged on the light incident side of the semi-transparent and semi-reflective prism, the light intensity detection module is arranged on a light emitting side of the semi-transparent and semi-reflective prism, the other light emitting side of the semi-transparent and semi-reflective prism faces the QR code, and the laser is arranged on the side of the collimator away from the semi-transparent and semi-reflective prism.

[0014] Preferably, the light intensity detection module includes a silicon photocell, a signal amplification circuit and an analog-to-digital conversion circuit.

[0015] Preferably, the ratio of transmittance to reflectivity of the semi-transparent and semi-reflective prism is 1:1.

[0016] The present application provides a device for reading a two-dimensional code in a transparent medium, which has the following beneficial effects:

[0017] The device for reading a two-dimensional code in a transparent medium arranges a camera and a light source on both sides of the two-dimensional code respectively, so that the part where the light source illuminates the transparent medium forms a bright area, and the part where the light source illuminates the two-dimensional code forms a dark area. This not only increases the contrast of the two-dimensional code, but also increases the depth range in which the depth system can clearly read the two-dimensional code, and enhances the compatibility with the height fluctuation of the material. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0019] Figure 1 This is a schematic diagram of the overall structure of Example 1 of the present application.

[0020] Figure 2 This is a schematic diagram of the structure of the light source in Example 1 of the present application.

[0021] Figure 3 This is a schematic diagram of the overall structure of Example 2 of the present application.

[0022] In the figure: 1. camera; 2. lens; 3. polarizer; 4. light source; 41. laser; 42. collimator; 43. semi-transparent and semi-reflective prism; 44. light intensity detection module; 5. transparent medium; 6. QR code; 7. polarized light detector. DETAILED DESCRIPTION

[0023] In order to make the purpose, features, and advantages of the present application more obvious and easy to understand, the technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the embodiments described below are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0024] In the description of the present application, it should be understood that the terms "upper", "lower", "top", "bottom", "inside", "outside", etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0025] The following is combined with Figure 1 -Attached Figure 3 The technical solution of this application is further illustrated through specific implementation methods.

[0026] Embodiment 1:

[0027] See also Figure 1 The present application provides a technical solution: a device for reading a two-dimensional code in a transparent medium, comprising an image capturing mechanism, an illumination mechanism and an image processing system.

[0028] See also Figure 1 and Figure 2 The image capturing mechanism is used to capture images. The image capturing mechanism includes a frame, a first linear module, a camera 1, a lens 2 and a polarizing plate 3. The base of the first linear module is fixedly connected to the frame, the camera 1 is fixedly connected to the slide of the first linear module, the lens 2 is fixedly connected to the camera 1 through a collar, and the polarizing plate 3 is fixedly connected to the lens 2. In this embodiment, the camera 1 is arranged on the positive side of the two-dimensional code 6. When the two-dimensional code 6 enters the field of view of the camera 1, the shooting direction of the camera 1 is perpendicular to the surface of the two-dimensional code 6. In addition, the polarizing plate 3 can filter glare and improve the shooting clarity of the camera 1.

[0029] See also Figure 1 and Figure 2, the lighting mechanism is used to illuminate the two-dimensional code 6, the lighting mechanism includes a light source 4 and a second linear module, the base of the second linear module is fixedly connected to the frame, and the light source 4 is fixedly connected to the slide of the second linear module. In this embodiment, the light source 4 is arranged in the opposite direction of the two-dimensional code 6, and the light emitting side of the light source 4 faces the two-dimensional code 6. When the two-dimensional code 6 enters the field of view of the camera 1, the irradiation direction of the light source 4 is perpendicular to the back of the two-dimensional code 6. The light source 4 includes a laser 41, a collimator 42, a semi-transparent and semi-reflective prism 43 and a light intensity detection module 44. The collimator 42 is arranged on the light incident side of the semi-transparent and semi-reflective prism 43, and the light intensity detection module 44 is arranged on one light emitting side of the semi-transparent and semi-reflective prism 43. The other light emitting side of the semi-transparent and semi-reflective prism 43 faces the two-dimensional code 6. The laser 41 is arranged on the side of the collimator 42 away from the semi-transparent and semi-reflective prism 43. The light intensity detection module 44 includes a silicon photocell, a signal amplifying circuit and an analog-to-digital conversion circuit. The silicon photocell converts the light intensity into a current signal, the signal amplifying circuit converts the current signal into a voltage signal, and the analog-to-digital conversion circuit converts the analog voltage signal into a digital signal.

[0030] The image processing system is used to process and analyze the image taken by the camera 1 , and the image processing system is electrically connected to the camera 1 .

[0031] To summarize, the device for reading a two-dimensional code in a transparent medium, by respectively arranging the camera 1 and the light source 4 on both sides of the two-dimensional code 6, makes the part where the light source 4 illuminates the transparent medium 5 form a bright area, and the part where the light source 4 illuminates the two-dimensional code forms a dark area. This not only increases the contrast of the two-dimensional code 6, but also increases the depth at which the two-dimensional code 6 can be clearly read, and increases the depth range at which the depth system can clearly read the two-dimensional code, thereby enhancing the compatibility with the height fluctuations of the material.

[0032] Embodiment 2:

[0033] See also Figure 3 The difference between this embodiment and the embodiment 1 is that the image capturing mechanism further includes a polarized light detector 7, and the lighting mechanism further includes a polarizer 3. In this embodiment, the polarizer 3 is arranged on the light exiting side of the light source 4, the polarized light detector 7 is arranged on the lens 2, and the polarizer 3 is no longer arranged on the lens 2.

[0034] By arranging a polarizing plate 3 on the light source 4, the light emitted by the light source 4 is polarized light. The degree of degradation of the polarized light when passing through the transparent medium 5 is low, and the degree of degradation of the polarized light when passing through the two-dimensional code 6 is high. The polarized light detector 7 can detect and filter the polarized light with a high degree of degradation, thereby improving the contrast between the two-dimensional code 6 and the transparent medium 5, which is beneficial for the image processing system to recognize the image. Moreover, in the actual production process, the height of the surface of the two-dimensional code 6 is different when different workpieces enter the code reading device. By arranging the polarized light detector 7, the blurring of the image caused by the fluctuation of the height of the workpiece can be reduced, thereby improving the applicability of the code reader.

[0035] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device.

[0036] Although the embodiments of the present application have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present application, and that the scope of the present application is defined by the appended claims and their equivalents.

[0037] As described above, the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A device for reading a two-dimensional code in a transparent medium, characterized in that: include: An image capturing mechanism, the image capturing mechanism comprising a camera (1) and a lens (2), the camera (1) being arranged in the front direction of the two-dimensional code, and the lens (2) being arranged on the camera (1); An illumination mechanism, the illumination mechanism comprising a light source (4), the light source (4) being arranged in the opposite direction of the two-dimensional code, and the light emitting side of the light source (4) facing the two-dimensional code; An image processing system, the image processing system is electrically connected to the camera (1), and the image processing system is used to process and analyze images taken by the camera (1).

2. The device for reading a two-dimensional code in a transparent medium according to claim 1, characterized in that: The image capturing mechanism further comprises a polarizing plate (3), wherein the polarizing plate (3) is arranged on a side of the lens (2) away from the camera (1).

3. The device for reading a two-dimensional code in a transparent medium according to claim 1, characterized in that: The image capturing mechanism further comprises a polarized light detector (7), which is arranged on a side of the lens (2) away from the camera (1); the lighting mechanism further comprises a polarizing plate (3), which is arranged on a light emitting side of the light source (4).

4. The device for reading a two-dimensional code in a transparent medium according to claim 3, characterized in that: The shooting direction of the camera (1) is perpendicular to the surface of the two-dimensional code.

5. The device for reading a two-dimensional code in a transparent medium according to claim 3, characterized in that: The lighting direction of the light source (4) is perpendicular to the back of the two-dimensional code.

6. The device for reading a two-dimensional code in a transparent medium according to claim 1, characterized in that: The light source (4) comprises a laser (41), a collimator (42), a semi-transparent and semi-reflective prism (43) and a light intensity detection module (44); the collimator (42) is arranged on the light incident side of the semi-transparent and semi-reflective prism (43); the light intensity detection module (44) is arranged on a light emitting side of the semi-transparent and semi-reflective prism (43); the other light emitting side of the semi-transparent and semi-reflective prism (43) faces the two-dimensional code; and the laser (41) is arranged on a side of the collimator (42) away from the semi-transparent and semi-reflective prism (43).

7. The device for reading a two-dimensional code in a transparent medium according to claim 6, characterized in that: The light intensity detection module (44) comprises a silicon photocell, a signal amplification circuit and an analog-to-digital conversion circuit.

8. The device for reading a two-dimensional code in a transparent medium according to claim 6, characterized in that: The ratio of transmittance to reflectivity of the semi-transparent and semi-reflective prism (43) is 1:1.

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