Color Inspection Device

Abstract

To provide a color tone inspection device with which it is made possible to accurately inspect a color tone independently of the accuracy of a lighting device or a light receiving device.SOLUTION: A placement member 3 to which reference color tone with the luminance value of R 128±10, the luminance value of G 128±10 and the luminance value of B 128±10 of the pixel represented by 256 gray levels is added, is provided to a bypass part 23 of a conveyor 2 in advance. Meanwhile, when an inspection object 10 does not exist, an image of reference color tone part 31 of the placement member 3 is acquired and a difference with the reference value of reference color tone preliminarily stored in storage means 7 is calculated. Meanwhile, when acquiring an image of the inspection object 10 and performing inspection, the luminance values of reference data stored in the storage means 7 or the luminance values of an image acquired by a light receiving device 5 are corrected on the basis of a difference value of these before performing inspection.SELECTED DRAWING: Figure 5

Description

[Technical field]

[0001] The present invention relates to a color tone inspection device that can inspect the color tone of a printed portion on the surface of an article, and more particularly, to a color tone inspection device that can inspect color tone with high accuracy without depending on the state of an illumination device or a light receiving device. [Background technology]

[0002] Conventionally, characters and patterns printed on product packages have been inspected visually or using inspection devices, etc. Among these, when an inspection device is used for inspection, an image of the surface of the product package is acquired and compared with inspection standard data stored in advance in a storage means, so that the printing condition of the product can be inspected based on whether or not a certain standard is met (Patent Document 1, etc.). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2020-190514 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, when performing inspection using the above-mentioned inspection device, the following problems arise.

[0005] That is, there are cases where the color tone of the printed part on the product package is extremely important. For example, in the case of cosmetics such as hair dye, paint, and lipstick, even a slight difference between the color printed on the product package and the actual color of the product may result in complaints from consumers.

[0006] Conventionally, it is possible to check the brightness of the lighting device by comparing it with pre-stored RGB reference data, but even if such a check is performed, the illuminance of the lighting device may change over time. For example, when using LED lighting, the fluorescent material may change over time, causing a change in color tone, or the resin in the LED lighting may discolor. In addition, in the case of white light bulbs, the brightness changes over time after they are turned on, and the color also changes slightly.

[0007] Furthermore, on the light receiving device side, the color filter of the camera may deteriorate over time, or the product precision of the light receiving element of the camera may fluctuate, causing the acquired color tone information to change.

[0008] Therefore, the present invention has been made with attention to the above-mentioned problems, and has an object to provide a color tone inspection device that can accurately inspect color tone without relying on the accuracy of the lighting device or the light receiving device. [Means for solving the problem]

[0009] That is, in order to solve the above problems, the present invention provides an illumination device that irradiates light onto an object to be inspected, a belt for transporting the inspection object; a mounting member for mounting the inspection object transferred from the belt and installed in an illumination area of ​​the illumination device; and light irradiated onto the inspection object mounted on the mounting member, A color tone inspection device including a light receiving device that receives reflected light, and an inspection means that inspects an object to be inspected based on information about the object to be inspected obtained by the light receiving device, a reference color tone section having a predetermined color tone is provided on a mounting member provided in a light irradiation area of ​​the lighting device; The inspection means performs inspection by correcting the color tone by the inspection means based on the color tone from the reference color tone portion of the mounting member.

[0010] With this configuration, even if a change occurs in the lighting device or the light receiving device, an image of the reference color tone is acquired and used for inspection, so that the color tone can be accurately inspected based on the color tone image. Furthermore, it becomes possible to obtain the color tone applied to the mounting member in a situation where the inspection object is not present, and to inspect the color tone of the inspection object based on that color tone.

[0011] In addition, in such an invention, The reference color tone portion is provided within the width of the belt.

[0012] Furthermore, the belt is configured to bypass the bottom of the placement member and receive and transport the inspection object from the placement member. Effect of the Invention

[0013] According to the present invention If, Even if a change occurs in the light-emitting device or the light-receiving device, an image of the reference color tone is acquired and used for inspection, so that it is possible to accurately inspect the color tone based on the image of the reference color tone. [Brief description of the drawings]

[0014] [Figure 1] 1 is a schematic diagram of a color tone inspection device according to an embodiment of the present invention; [Diagram 2] Functional block diagram of the same configuration [Diagram 3] FIG. 2 shows an illumination device, a light receiving device, and a reference color tone unit in the embodiment. [Figure 4] FIG. 13 shows another reference color tone section in the same form. [Diagram 5] FIG. 13 is a flowchart showing the inspection in the same embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0015] Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

[0016] The color tone inspection device 1 in this embodiment is adapted to inspect the color tone applied to a product package, and as shown in Fig. 1, is configured to include a conveyor 2 for transporting an inspection object 10, which is a product package, an illumination device 4 for irradiating light onto the inspection object 10 transported on the conveyor 2, and a light receiving device 5 for acquiring an image of the inspection object 10 illuminated by the illumination device 4. Characteristically, a mounting member 3 for mounting the inspection object 10 is provided within a light receiving area of ​​the light receiving device 5, the mounting member 3 is colored in a reference color tone, and the RGB of the reference color tone is compared with the RGB brightness of the inspection object 10 to correct the RGB brightness value for inspection. Hereinafter, this embodiment will be described in detail.

[0017] 1, the conveyor 2 for transporting the inspection object 10 is configured with a plurality of rollers 21 and a belt 22 encircled by these rollers 21, and the inspection object 10 can be placed and transported on the belt 22. Among these, a detouring section 23 is provided in the light receiving area of ​​the light receiving device 5 in the conveyor 2 so that the inspection object 10 can be handed over to the mounting member 3 described below, and after the transported inspection object 10 is handed over to the mounting member 3 and the belt 22 is detouring downward, the inspected inspection object 10 can be received from the mounting member 3 and transported.

[0018] The lighting device 4 is capable of irradiating the inspection target 10 with light, and is provided by arranging multiple light-emitting members inside a lighting fixture 41 configured in a semi-cylindrical shape. As the light-emitting members, halogen lamps, fluorescent lamps, LEDs, etc. are used, and in particular, when LEDs are used, it is possible to independently irradiate different colors.

[0019] On the other hand, the light receiving device 5 is configured to receive the light that is incident through the slit 42 of the lighting fixture 41 out of the light irradiated by the lighting device 4, and a line sensor or the like is used for this light receiving device. The width direction of this line sensor is the short side direction of the conveyor 2, and the light receiving direction is inclined toward the conveying direction with respect to the normal to the conveying surface.

[0020] In such a configuration, in order to obtain accurate color tone information without depending on the accuracy of the illumination device 4 or the light receiving device 5, a reference color tone section 31 is provided within the light receiving area of ​​the light receiving device 5, and inspection can be performed by making corrections based on the color tone colored in this reference color tone section 31.

[0021] As shown in FIG. 3, the reference color tone section 31 is provided by coloring the mounting member 3, and RGB luminance information is obtained in advance by another color tone inspection device 1 or the like. In this case, the reference color tone section 31 is provided with a gray color that can obtain luminance values ​​of 128±10 as the R luminance value, 128±10 as the G luminance value, and 128±10 as the B luminance value when expressed in 256 gradations. The mounting member 3 colored with the reference color tone is provided in a slit-shaped light receiving area, so that an image of the reference color tone can be obtained when the inspection target 10 is not being conveyed. Note that, although the luminance value is set near the median value of 256 gradations here, it may be near the median value of 1024 gradations, or may be another luminance value.

[0022] Although a single-color reference tone section 31 is provided here, an R-colored section 31a, a G-colored section 31b, and a B-colored section 31c may be provided independently, as shown in FIG. 4, and the luminance of each may be set within the range of 128±10.

[0023] The correction means 6 performs a color tone correction process based on the reference color tone part 31, and corrects the RGB of the reference data stored in the storage means 7, or corrects the RGB brightness value of the image information received by the light receiving device 5. Specifically, when the reference color tone part 31 of the mounting member 3 is colored so that R=r0, G=g0, and B=b0, and the pixels of the reference color tone received by the light receiving device 5 of this color tone inspection device 1 are R=r1, G=g1, and B-b1, the differences ΔR=r0-r1, ΔG=g0-g1, and ΔB=b0-b1 are obtained. Then, the differences are corrected from the RGB brightness value of the pixel of the inspection reference data, or from the RGB brightness value of the image of the inspection object 10 received by the light receiving device 5. These corrections are performed every time the transported inspection object 10 is inspected.

[0024] The inspection means 8 performs the inspection by comparing image information based on the image received by the light receiving device 5 with the reference data stored in the storage means 7. At this time, for example, it is judged whether or not pixels with RGB luminance within a predetermined width exist at a position corresponding to a pixel at a specific position of the inspection object 10, and if pixels with other luminance values ​​exist continuously for a predetermined period or more, it is judged to be "defective". Of course, the quality of the inspection object 10 may be inspected by other algorithms, but when performing these inspections, the luminance information corrected by the correction means 6 is used. When performing such correction, the reference data is corrected and the corrected reference data is compared with the image data of the inspection object 10 acquired by the light receiving device 5 to make a judgment, or the luminance value of the image data on the inspection object 10 side is corrected and the corrected luminance value is compared with the luminance value of the reference data stored in the storage means 7 to perform the inspection.

[0025] The output means 9 outputs the inspection results judged by the inspection means 8, and outputs not only the pass / fail result of the inspection but also the parts judged to be defective, etc. Also, when performing the correction process, if the RGB correction value is extremely large, there is a possibility that a malfunction has occurred in the lighting device 4 or the light receiving device 5, so the correction value may also be output so that it can be judged by visual inspection, or if the correction value is larger than a predetermined threshold value, it may be judged that a malfunction has occurred in the lighting device 4 or the light receiving device 5 and a notification may be issued.

[0026] Next, a process using the color tone testing device 1 configured as above will be described with reference to the flowchart of FIG.

[0027] First, when inspecting the inspection target 10, the mounting member 3 is attached to the color tone inspection device 1 capable of accurately acquiring color tones in advance, and RGB luminance information (r0, g0, b0) which is the reference color tone of the mounting member 3 is acquired and stored in the storage means 7 (step S1). Then, the mounting member 3 is attached to the color tone inspection device 1 to be used this time.

[0028] Then, the color tone inspection device 1 is turned on to drive the lighting device 4, the light receiving device 5, the conveyor 2, etc., and the reference color tone of the mounting member 3 is obtained by the light receiving device 5. At this time, the luminance information (r1, g1, b1) of the RGB is obtained (step S2).

[0029] Then, the difference between the acquired RGB information (r1, g1, b1) and the RGB luminance value (r0, g0, b0) of the reference color tone stored in advance in the storage means 7 is calculated (step S3).

[0030] When the inspection object 10 is transported on the conveyor 2 in this state, the inspection object 10 is transferred from the conveyor 2 to the mounting member 3, and an image of the surface of the inspection object 10 is acquired by the light receiving device 5 (step S4).

[0031] Then, image data based on the image of the surface of the inspection object 10 is compared with inspection reference data previously stored in the storage means 7 to inspect the suitability of RGB for each pixel. At this time, the difference calculated in step S3 is used to correct the RGB luminance value of each pixel of the inspection reference data, or the RGB luminance value of each pixel based on the image acquired from the inspection object 10 is corrected (step S5). Then, it is determined whether or not each pixel falls within a predetermined threshold range (step S6), and if there are multiple consecutive pixels that exceed the threshold, an output indicating that the pixel is defective is issued (step S8).

[0032] On the other hand, if there are no defects in any of the pixels, or if there are defective pixels but the number is within a predetermined range, an output indicating that the product is non-defective is made (step S7).

[0033] As described above, according to the embodiment, the illumination device 4 irradiates the inspection object 10 with light, A belt 22 for transporting the inspection object 10, a mounting member 3 on which the inspection object 10 delivered from the belt 22 is placed and which is installed in the illumination area of ​​the illumination device 4, and light irradiated onto the inspection object 10 placed on the mounting member 3, A color tone inspection device 1 including a light receiving device 5 for acquiring reflected light and an inspection means 8 for inspecting the quality of an inspection object 10 based on information about the inspection object 10 acquired by the light receiving device 5, A reference color tone section 31 having a predetermined color tone is provided on a mounting member 3 provided in an irradiation area of ​​the light from the lighting device 4,The inspection means 8 is adapted to correct the color tone based on the color tone from the reference color tone portion 31 of the mounting member 3 and perform inspection. Therefore, even if there is a change in the illumination or light reception, an image of the reference color tone image is obtained and inspection is performed, so that accurate color tone inspection can be performed based on that image.

[0034] The present invention is not limited to the above-described embodiment, but can be embodied in various forms.

[0035] For example, in the above embodiment, the inspection object 10 is transported by the conveyor 2 and inspected, but the present invention can also be applied to a case where the inspection object 10 is placed on a table such as a stage and inspected.

[0036] In addition, in the above embodiment, a mounting member 3 is placed in the detouring section 23 of the conveyor 2, and correction is made using the color of the mounting member 3, but it is also possible to transport an article having a reference color tone and make correction based on that color.

[0037] Furthermore, in the above embodiment, correction is performed each time using the color of the reference color tone section 31, but if there is no difference from the RGB luminance acquired by the light receiving device 5, correction may not be performed, and correction may be performed only if there is a difference of a certain level or more. [Explanation of symbols]

[0038] 1. Color inspection device 2. Conveyor 21. Roller 22. Belt 23...Detour section 3 (31) Placing member (reference color tone portion) 4. Lighting equipment 41 Lighting fixture 42...Slit 5... Light receiving device 6...Correction means 7...Memory means 8. Inspection method 9. Output means 10. Inspection object

Claims

1. An illumination device that irradiates light onto the inspection object; A belt for transporting the inspection object; a placement member on which the inspection object transferred from the belt is placed and which is disposed in an illumination area of ​​the illumination device; a light receiving device that receives reflected light from the light irradiated onto the inspection object placed on the placement member; an inspection means for inspecting the quality of an object to be inspected based on information about the object to be inspected acquired by the light receiving device; In a color tone inspection device comprising: a reference color tone section having a predetermined color tone is provided on a mounting member provided in a light irradiation area of ​​the lighting device; a color tone inspection device, characterized in that the inspection means performs inspection by correcting the color tone by the inspection means based on the color tone from the reference color tone portion of the mounting member.

2. A color tone inspection device as described in Claim 1, wherein the reference color tone portion is provided within the width of the belt.

3. A color inspection device as described in claim 1, wherein the belt bypasses the bottom of the mounting member to receive and transport the object to be inspected from the mounting member.

Images