CN212568538U - Digital dot image detection device - Google Patents

Digital dot image detection device Download PDF

Info

Publication number
CN212568538U
CN212568538U CN202021216663.4U CN202021216663U CN212568538U CN 212568538 U CN212568538 U CN 212568538U CN 202021216663 U CN202021216663 U CN 202021216663U CN 212568538 U CN212568538 U CN 212568538U
Authority
CN
China
Prior art keywords
image
dot
printing
site
proof
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Active
Application number
CN202021216663.4U
Other languages
Chinese (zh)
Inventor
张研
王东琦
吕伟
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Anhui Antai New Style Packaging Materials Co ltd
Shenzhen Jinjia Group Co Ltd
Original Assignee
Anhui Antai New Style Packaging Materials Co ltd
Shenzhen Jinjia Group Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Anhui Antai New Style Packaging Materials Co ltd, Shenzhen Jinjia Group Co Ltd filed Critical Anhui Antai New Style Packaging Materials Co ltd
Priority to CN202021216663.4U priority Critical patent/CN212568538U/en
Application granted granted Critical
Publication of CN212568538U publication Critical patent/CN212568538U/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Abstract

The utility model discloses a digital site image detection device, wherein digital site image detection device, include: a detect platform for placing the printed matter for shoot the printed matter and predetermine regional image and the enlarged site of region and enlarge the display device who shoots the appearance and be used for showing the site and enlarge the image of shooing the appearance and shooting, it is provided with the support to detect bench, the site enlarge shoot appearance slidable set up in on the support to be connected with display device through the data line. The utility model discloses a site is enlarged and is shot the image that the appearance was shot standard proof and printing proof respectively, through data line transmission to display device in to can contrast the collection image of standard proof and printing proof directly perceivedly through display device, observe the site form difference of enlarging back standard proof and printing proof printed matter, thereby produce the adjustment, improve the detection accuracy.

Description

Digital dot image detection device
Technical Field
The utility model relates to a printing technology field, in particular to digital site image detection device.
Background
Printing is a technique of transferring ink to the surface of a printing material by performing processes such as plate making, inking, and pressing on an original containing information such as characters and pictures, and copying the contents of the original in bulk. In the existing packaging printing technology, after pictures and texts are directly printed on paper or other printing materials (such as PET films) through a plurality of printing color set units, the paper or other printing materials are cut into packaging boxes or packaging bags.
In the printing process, the printing quality needs to be checked in a sampling mode, and the color difference, the definition, the dot position, the dot size and the like are mainly detected. At present, generally, an on-line image detection device performs image analysis on a produced printing sample sheet and a standard sample sheet prestored in a computer to judge whether errors such as large-area missing printing exist, but small-area dot difference cannot be evaluated, and high-precision control on printing color and printing effect cannot be realized. For detecting the dot difference, a magnifying glass is generally adopted for watching and comparing the standard sample sheet and the production sample sheet by human eyes to estimate the dot difference between the standard sample sheet and the printing sample sheet, so that the production adjustment can be carried out. However, the magnification of the magnifier is generally 5-10 times, and observation by using the magnifier and human eyes not only depends on the experience level of technologists, but also cannot accurately regulate and control observation errors, and is time-consuming and labor-consuming.
Thus, the prior art has yet to be improved and enhanced.
SUMMERY OF THE UTILITY MODEL
In view of the above-mentioned prior art's weak point, the utility model aims to provide a digital dot image detection device can enlarge the printing and shoot and show, supplies the dot difference to observe.
For solving the technical problem, the utility model discloses following technical scheme has been taken:
a digital dot image detecting apparatus, comprising: a detect platform for placing the printed matter for shoot the printed matter and predetermine regional image and the enlarged site of region and enlarge the display device who shoots the appearance and be used for showing the site and enlarge the image of shooing the appearance and shooting, it is provided with the support to detect bench, the site enlarge shoot appearance slidable set up in on the support to be connected with display device through the data line.
The digital dot image detection device further comprises a first sliding device used for controlling the dot amplification shooting instrument to move, the first sliding device comprises a first sliding block, a first sliding rail, a screw rod and a motor, the screw rod and the first sliding rail are arranged on the support, one part of the first sliding block is sleeved on the screw rod and is in threaded connection with the screw rod, the other part of the first sliding block is sleeved on the first sliding rail and is connected with the dot amplification shooting instrument, and the motor is connected with one end of the screw rod.
In the digital dot image detection device, an air suction hole for adsorbing a printed matter is arranged on the detection table.
In the digital dot image detection device, a second slide rail is arranged on the detection table, a second slide block is arranged on the second slide rail, and the support is arranged on the second slide block.
In the digital dot image detection device, an air suction hole for adsorbing a printed matter is arranged on the detection table.
In the digital dot image detection device, a positioning ruler is arranged on the detection table.
In the digital dot image detection device, a shooting lens of the dot amplification shooting instrument is provided with a framing positioning line.
In the digital dot image detection device, the display device is arranged on the detection table through a support frame, and the display device is rotatably connected with the support frame.
In the digital dot image detection device, a third slide rail is further arranged on one side of the detection table, a third slide block is arranged on the third slide rail, and the support frame is arranged on the third slide block.
In the digital dot image detection device, a non-reflective neutral gray coating is arranged on the detection table.
Compared with the prior art, the utility model provides a digital site image detection device, wherein digital site image detection device passes through the site is enlargied and is shot the appearance and can enlarge the shooting as required magnification, and the image can clearly observe the site form, the site interval and the site of printed matter and warp etc.. The utility model discloses place standard proof and printing proof on examining test table, through the site is enlarged and is shot the image that the appearance was shot standard proof and printing proof respectively to transmit to display device through the data line in, thereby display device can contrast the collection image of standard proof and printing proof directly perceivedly, observe the site form difference of enlarging back standard proof and printing proof printed matter, thereby produce the adjustment, improved the detection precision.
Drawings
Fig. 1 is a schematic diagram of the structure of the digital dot image detection device provided by the present invention.
Fig. 2 is the schematic diagram of the digital dot image detection device according to the present invention, which is used when the blue dots of the standard proof and the printing proof are shot by the framing and positioning lines on the dot amplification shooting instrument.
Fig. 3 is a block diagram of an image detection system of the digital dot image detection apparatus provided by the present invention.
Fig. 4 is a flowchart of a detection method of the detection device of the digital dot image detection device according to the present invention.
Fig. 5 is a schematic diagram of image color separation processing in the detection method of the detection device of the digital halftone image detection device provided by the invention.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.
It will be understood that when an element is referred to as being "on," "secured to" or "disposed on" another element, it can be directly on the other element or intervening elements may also be present. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or intervening elements may also be present.
It should be noted that the terms of orientation such as left, right, up and down in the embodiments of the present invention are only relative to each other or are referred to the normal use state of the product, and should not be considered as limiting.
Referring to fig. 1, the present invention provides a digital dot image detecting device, including: detect platform 1, site and enlarge shooting appearance 2 and display device 3, it is provided with support 4 on the platform 1 to detect, the site enlarge shoot appearance 2 slidable set up in on the support 4 to be connected with display device 3 through data line 5.
The detection table 1 is used for placing a printed matter, the dot amplification shooting instrument 2 is used for shooting an image of a preset area of the printed matter and amplifying the image, and the display device 3 is used for displaying the image shot by the dot amplification shooting instrument 2. The dot amplification shooting instrument 2 can shoot by amplification times according to needs, so that dot shapes, dot intervals, dot deformation and the like of the printed matter can be clearly observed. The utility model discloses place standard proof and printing proof on examining test table 1, by the net point enlargies the image of taking 2 shooting standard proofs and printing proofs of appearance, transmits to display device 3 in through data line 5 to can follow the collection image of display device 3 contrast standard proof and printing proofs directly perceivedly, supply to observe the net point form difference of enlargiing back standard proof and printing proof printed matter, thereby produce the adjustment, reduced and enlarged with the magnifying glass, the error of experience judgement has improved the detection precision.
In this embodiment, the dot magnification camera 2 has a standard light source commonly used for detecting printed matters, and 5 types of commonly used standard light sources include D65 (international standard workers light, 6500K), D50 (simulated sunlight, 5000K), TL84 (european, japanese, chinese shop light source, 4000K), F (home hotel light, 2700K) and UV ultraviolet light source (365nm), and are used for observing the product colors in different color lights. Of course, the standard light source of the present invention is not limited to the above 5 types.
The magnification of the dot magnification camera 2 is adjustable, and the magnification of the dot magnification camera 2 in this embodiment may be 40 to 200 times, and 10 times is used as the adjustment step length. In daily production, the magnification of the printed matter is about 5-100 times, and the dot shape, the dot pitch, the dot deformation and the like can be clearly observed by 100 times. The multiple of 40-200 times is adopted here, and the method can be applied to images with smaller sizes, but is not limited to images with smaller sizes, so that the compatibility of the dot image detection device is higher.
Further, the dot amplification shooting instrument 2 can adopt an electronic magnifier, a digital display lens and the like, and can be used for online acquisition and offline acquisition so as to be suitable for image acquisition in different environments.
The digital dot image detection device also comprises a main control device (not shown in the figure) for installing an image detection system and storing images collected by the dot amplification shooting instrument 2, which is beneficial to the analysis of the image detection system and the quantification of dot deformation parameters of printed matters, thereby carrying out production adjustment. The display device 3 is electrically connected with a main control device, and the main control device can be a computer, a tablet, a mobile phone or other developed special equipment.
In this embodiment, the digital dot image detecting device further includes a first sliding device 6 for controlling the dot magnifying camera 2 to move, the first sliding device 6 includes a first sliding block 61, a first sliding rail 62, a screw 63 and a motor 64, the screw 63 and the first sliding rail 62 are both disposed on the bracket 4, a part of the first sliding block 61 is sleeved on the screw 63 and screwed with the screw 63, another part of the first sliding block 61 is sleeved on the first sliding rail 62 and is connected and fixed with the dot magnifying camera 2, and the motor 64 is connected with one end of the screw 63.
When the position of the dot amplification shooting instrument 2 in one direction needs to be adjusted, the motor 64 rotates forward or backward to drive the screw rod 63 to rotate coaxially, and the rotation of the screw rod 63 enables the first slide block 61 to move on the first slide rail 62 (for example, to move along the X-axis direction or the Y-axis direction), so that the dot amplification shooting instrument 2 connected with the first slide block 61 moves synchronously. Further, the dot magnification camera 2 is rotatably connected with the first sliding block 61 and can be lifted, so that the dot magnification camera can rotate to take an angle according to needs, and the dot magnification camera 2 can be lifted and adjusted, so that an ideal focusing distance can be found.
Referring to fig. 1, a second slide rail 11 is arranged on the detection table 1, a slidable second slide block 12 is arranged on the second slide rail 11, the support 4 is arranged on the second slide block 12, the second slide block 12 moves on the second slide rail 11 (for example, moves along the Y-axis direction or the X-axis direction), so that the support 4 moves synchronously, the dot gain shooting instrument 2 can move along the X-axis direction, the Y-axis direction, the Z-axis (lifting), the rotation angle and other four dimensions are adjusted by combining the first slide device 6, and the amplification function of the dot gain shooting instrument 2 is combined to realize an omnidirectional image view finding mode, so that sampling at any position and any angle of 360-degree full-width surface is ensured, and shooting requirements are met.
Further, an air cylinder (not shown in the figure) is further arranged on the detection table 1, and a telescopic end of the air cylinder is connected with the second sliding block 12, so that the movement of the second sliding block 12 can be controlled through the air cylinder. The motor 64 and the cylinder are electrically connected with the main control device, so that the dot amplification shooting instrument 2 can automatically move as required to collect images.
In this embodiment, the display device 3 is disposed on the detection table 1 through the supporting frame 31, and the display device 3 is rotatably connected to the supporting frame 31, so that the direction of the display device 3 can be adjusted, and the operation of a worker is facilitated. Further, one side of the detection table 1 is further provided with a third slide rail 13, a third slide block 14 is arranged on the third slide rail 13, and the support frame 31 is arranged on the third slide block 14, so that the display device 3 can move as required to meet the use requirement.
In an alternative embodiment, the size of the test station 1 is 800 × 1000mm, which is larger than the size of a single printed sheet to ensure that the sample is completely placed and observed. Preferably, a non-reflective neutral gray coating is arranged on the detection table 1, so that the influence of the brightness and color of the detection table 1 on the brightness and color of the standard sample sheet and the printing sample sheet is avoided.
In this embodiment, the detection table 1 is provided with an air suction hole 15 for adsorbing a printed matter. Because the thickness difference of printed matter, the sample can produce little stick up limit deformation in the printing, through induced draft hole 15 makes can make the smooth shop of printed matter on the platform.
Preferably, the distance between the air suction holes 15 is not too large, so that the method can be applied to smaller samples, such as: for a cut sample of 100X 200mm, the spacing between the aspiration holes 15 may be less than 80X 80 mm.
As shown in fig. 1, the detection table 1 is provided with a positioning ruler 16 for aligning the initial placement positions of the standard proof and the printed proof, so that the shooting at the same position can be completed without adjusting the position of the dot amplification shooting instrument 2, and the error caused by different shooting positions is avoided.
Referring to fig. 2 and fig. 3, an image capturing frame 201 is disposed when the shooting lens of the dot gain shooting device 2 shoots, a collecting frame 202 is disposed in the capturing frame 201, and a framing positioning line 21 is disposed on the collecting frame 202, so that a framing position of an image can be accurately positioned.
In operation, the image is captured through the capture frame 201, the corresponding area needing enlarged shooting is found, then the shooting lens can automatically acquire a clear image, then the frame position of the image is acquired through the acquisition frame 202, and then the enlarged image of the frame position is shot.
In order to observe the same unknown information such as the screen dot screening angle, the screen line number and the like of the standard sample sheet and the printing sample sheet, the viewing direction of the viewing positions of the standard sample sheet and the printing sample sheet can be kept completely consistent by utilizing the viewing positioning line 21, and then images are collected, so that the accuracy of the detection result is ensured, and the production quality is improved.
The utility model discloses an it sets up location chi 16 to examine test table for location standard proof and printing proof, what make standard proof and printing proof gather is the image of same region, and the site is enlarged and is shot appearance 2 and catch the shooting region after enlarging the image, and later auto focus, the rethread is looked a frame location line 21, finds the accurate position that the sample needs to gather, thereby acquires the local picture and text information region that standard proof and printing proof need compare. The selection of the local pattern or the local image-text information is determined according to the observation requirement, and particularly, a certain micro pattern on a large sample sheet needs to be checked for the difference between the printing sample sheet and the standard sample sheet, and the position is selected as a positioning object, so that the effect that the viewing positions of the standard sample sheet and the printing sample sheet are consistent can be realized.
In this embodiment, the framing positioning line 21 is a scale mark on the edge of the collecting frame, and the positions of the standard proof and the printed proof can be determined by using the scale mark, so that the effect that the framing positions of the standard proof and the printed proof are consistent can be achieved. Meanwhile, the image acquisition of the standard proof and the printing proof needs to be guaranteed to have the same magnification. In specific implementation, the scale mark may be inside the collection frame 202, as shown in fig. 2(a), or may be outside the collection frame 202, as shown in fig. 2(b), or may be inside or outside the collection frame 202, as shown in fig. 2(c), which is not limited to this.
In the image acquisition of the embodiment, the image-text information captured on the standard proof and the printing proof is determined to be an accurate range and used for dot analysis. The image range observed by the lens is in the capturing frame, the lens can be moved and rotated for positioning in the image capturing process, the graduated scale is arranged on the image acquisition frame, and the acquired image can not be moved and rotated but can not be amplified and reduced so as to obtain the image-text information of the consistent position of the standard sample sheet and the printing sample sheet. And shooting and transmitting the images in the acquisition frame to the main control device by utilizing a view finding function and displaying the images on a screen.
Preferably, the digital dot image detection device further includes an image detection system for comparing dot differences of images acquired by the standard proof and the printed proof, the image detection system is solidified in the main control device, and the image detection system includes: an overall difference detection unit 100, an image color separation difference detection unit 200, a printing plate information difference detection unit 300, and a result output unit 400.
Wherein the overall difference detecting unit 100 is configured to detect an overall difference between the standard proof image and the print proof image; the image color separation difference detection unit 200 is configured to detect an image color separation difference when the overall difference is smaller than a set value; the printing plate information difference detection unit 300 is used for detecting the printing plate information difference when the color separation difference is smaller than a set value; the result output unit 400 is used for outputting the detection result and sending the detection result to the display device 3 for displaying the detection result.
Thus, the content detectable by the image detection system includes:
(1) integral difference of images: such as sharpness, color deviation, etc.
In an alternative embodiment, the step of sharpness detection comprises: converting the color image into a grayscale image, the sharply focused image having a greater grayscale difference than the blurred image, and thereafter: judging the image definition by using a variance function as an evaluation function, wherein the evaluation function comprises the following steps:
D(f)=∑yx|f(x,y)-μ|2
wherein μ is an average gray value of the whole image, and the larger the value of the evaluation function is, the sharper the image is.
The step of color deviation detection includes: transforming the image in the acquisition frame to Lab space, and then calculating L of each pixel in the image*,a*,b*Value of, then a for each pixel*,b*The values are summed, the result being:
Figure BDA0002558254680000081
Figure BDA0002558254680000082
the overall color deviation of the image is then:
Figure BDA0002558254680000083
Figure BDA0002558254680000084
wherein D isAAs red-green deviation of the image, DBIn order to be the deviation of the yellow-blue image,
Figure BDA0002558254680000085
the a value of each pixel of the proof,
Figure BDA0002558254680000086
the a values for each pixel of the print swatch,
Figure BDA0002558254680000087
the b values of the pixels of the standard proof,
Figure BDA0002558254680000088
b values of all pixels of the printing sample sheet are represented, when DA is larger than 0, the color of the printing sample sheet is relatively green, otherwise, the color of the printing sample sheet is relatively red; when Db is more than 0, the color of the printed sample is blue, otherwise, the color of the printed sample is yellow.
(2) Difference of image color separation: because the printing image is formed by the dot overprinting of different colours, the utility model discloses a distinguish different colours and divide, only contrast the difference of a certain colour dot on standard proof and the printing proof, for example only contrast the yellow dot (like the slash filling part in fig. 2) of standard proof and printing proof to do benefit to dot difference classification processing. By utilizing a clustering algorithm, classification processing is carried out on the dots of different colors of the image, and the differences of the dots of each color in the standard sample sheet and the printing sample sheet, including but not limited to the information of area ratio, size, shape and the like, can be analyzed;
the detection step of the image color separation difference comprises the following steps: reading the color value of each pixel point of the dot image in the collection frame, as shown in (a) of fig. 5, the honeycomb part represents cyan dots, the grid filled honeycomb filled part represents magenta dots, the slash filled part represents yellow dots, and the RGB values corresponding to the CMYK monochrome dots are (0,255,255), (255,0,255), (255, 0) (0,0,0), respectively. Then, the dot images are subjected to color separation processing by using a fuzzy clustering algorithm, and the images of different dots are respectively displayed, as shown in (b) of fig. 5.
And then, carrying out area ratio calculation, size measurement and shape analysis on the single-color dots.
Wherein, the dot area rate a is obtained by counting the total number N of dot pixels in the monochrome imagedAccounts for the total number of pixels N in the imageAThe ratio of (A) to (B) is obtained:
Figure BDA0002558254680000091
(3) difference of printing plate information: the method mainly comprises the detection of printing plate information such as screening angles, screening line numbers and the like, and when the screening angles, the screening line numbers, the dot shapes and the dot sizes of the standard sample sheets and the printing sample sheets are different, the standard sample sheets and the printing sample sheets can be adjusted according to the measurement results.
The screening angle is the included angle between the dot arrangement line and the horizontal line. And selecting the arrangement direction of the lattice points by using a measuring scale, and calculating the included angle between the lattice points and the horizontal line.
The number of the screen lines is the number of the screen points included in a unit length along the direction of the screen line angle. Selecting the arrangement direction of the dots by using a measuring ruler, and measuring the dot center point pitch p, wherein the dot center point pitch p is obtained by calculating the following formula:
Figure BDA0002558254680000101
and obtaining the number of the screened lines.
Finally, the result output unit 400 judges the results of the overall image difference, the color separation difference and the printing plate difference.
In an optional embodiment, the image detecting system of the present invention further includes a measuring ruler unit, which can measure the dots by using the measuring ruler, and determine the dot difference (such as the size, the screening angle, the number of the screened lines, etc.) between the printed sample sheet and the standard sample sheet, thereby modifying the printing parameters. The measured differences may suggest process modifications. If the measured printing proof screen point is 20um and the measured standard printing proof screen point is 25um, the printing screen point on the printing plate of the corresponding printing color group can be increased by adjusting the process parameters, so that the effect of being consistent with the standard printing proof is achieved.
For example, by measuring the standard proof blue screening angle at 30 degrees and the measured print proof screening angle at 25 degrees, the blue plate can be modified to change the screening angle to 30 degrees. Because the magnification factor is fixed, the measured actual size/magnification factor of the dots is equal to the printing size, the printing dot size of the standard sample sheet and the printing sample sheet can be compared, if the dots of the printing sample sheet are too large, the size of the dots on the printing plate needs to be reduced, and the printed dots are small.
Further, when the parameters of the standard proof and the printed proof are unknown, the dot shape and size of the standard proof can be observed by magnifying the standard proof, and according to the difference, for example: the standard sample sheet is a square dot, the printing sample sheet is a round dot, the dot shape of the printing sample sheet needs to be adjusted, and the difference can be judged for process correction; process optimization can be performed when the standard proof and print proof parameters are known. And adjusting the printing plate parameters according to the detection result.
The utility model discloses an image detection system can carry out automated inspection, need not human eye observation, manual measurement etc. has improved digital site image detection device's intelligent degree.
Referring to fig. 4, based on the above-mentioned digital dot image detection device, the present invention further provides a detection method using the digital dot image detection device, which includes the following steps:
s100, amplifying a standard specimen image by a dot amplification shooting instrument arranged above the detection table, collecting an image of a set area and sending the image to a display device;
s200, amplifying the printing sample image by the dot amplification shooting instrument, collecting the printing sample image in a set area and sending the printing sample image to a display device; the position of the standard sample sheet image collected by the dot amplification shooting instrument is the same as the position of the printing sample sheet image;
and S300, displaying the standard sample image and the printing sample image by the display device.
Wherein the step S100 includes:
s110, amplifying and capturing a standard sample image, and positioning and framing;
and S120, acquiring a view area image and sending the view area image to a display device.
The step S200 includes:
s210, amplifying and capturing an image of the printing sample, and positioning and framing; the framing positions of the standard proof image and the printing proof image are the same;
and S220, acquiring the image of the view area and sending the image to the display device.
After step S300, the method further includes:
s400, detecting the integral difference between the standard sample image and the printing sample image;
s500, detecting color separation difference of the image when the overall difference is smaller than a set value;
s600, detecting the difference of the printing plate information when the color separation difference is smaller than a set value;
and S700, displaying the detection result.
By using the detection method, the difference between the standard sample and the printing sample can be automatically detected without human eye observation, manual measurement and the like, and the intelligent degree of the digital dot image detection device is improved.
Wherein, S400 is mainly used for detecting the definition and color deviation of the image; wherein:
the detecting of the sharpness comprises:
converting the color image into a gray image, wherein the sharply focused image has larger gray difference than the blurred image;
judging the image definition by using a variance function as an evaluation function, wherein the evaluation function comprises the following steps:
D(f)=∑yx|f(x,y)-μ|2
wherein mu is the average gray value of the whole image, and the image is clearer when the value of the evaluation function is larger;
the method for detecting the color deviation comprises the following steps: transforming the image in the acquisition frame to Lab space, and then calculating L of each pixel in the image*,a*,b*Value of, then a for each pixel*,b*The values are summed, the result being:
Figure BDA0002558254680000121
Figure BDA0002558254680000122
the overall color deviation of the image is then:
Figure BDA0002558254680000123
Figure BDA0002558254680000124
wherein D isAAs red-green deviation of the image, DBIn order to be the deviation of the yellow-blue image,
Figure BDA0002558254680000125
the a value of each pixel of the proof,
Figure BDA0002558254680000126
the a values for each pixel of the print swatch,
Figure BDA0002558254680000127
the b values of the pixels of the standard proof,
Figure BDA0002558254680000128
b values of all pixels of the printing sample sheet are represented, when DA is larger than 0, the color of the printing sample sheet is relatively green, otherwise, the color of the printing sample sheet is relatively red; when Db is more than 0, the color of the printed sample is blue, otherwise, the color of the printed sample is yellow.
The step S500 includes: in detecting the color separation difference, the detecting of the color separation difference comprises:
reading the color value of each pixel point of the screen image in the collection frame;
carrying out color separation processing on the dot images by using a fuzzy clustering algorithm, and respectively displaying images of different dots;
carrying out area rate calculation, size measurement and shape analysis on the monochromatic screen points;
wherein, the dot area rate a is obtained by counting the total number N of dot pixels in the monochrome imagedAccounts for the total number of pixels N in the imageAThe ratio of (A) to (B) is obtained:
Figure BDA0002558254680000129
in step S600, the step of detecting the printing plate information difference includes detecting a screening angle, a screening number, a dot shape, and a dot size, when the screening angle, the screening number, the dot shape, and the dot size are different between the standard proof and the printing proof, and when the color separation difference is smaller than a set value, the step of detecting the printing plate information difference includes:
selecting the arrangement direction of the lattice points by using a measuring ruler, and calculating the included angle between the lattice points and the horizontal line;
selecting the arrangement direction of the dots by using a measuring ruler, and measuring the dot center point pitch p, wherein the dot center point pitch p is obtained by calculating the following formula:
Figure BDA0002558254680000131
and obtaining the number of the screen wires according to the direction of the screen wire angle and the number of the screen wires contained in the unit length.
To sum up, the utility model discloses a site enlargies shoots the appearance and can enlarge the multiple as required, can clearly observe the site form, the site interval and the site deformation etc. that detect the printed matter on the bench. During detection, the standard sample sheet and the printing sample sheet are placed on the detection table, the images of the standard sample sheet and the printing sample sheet are shot by the dot amplification shooting instrument and transmitted to the display device through the data line, the collected images of the standard sample sheet and the printing sample sheet can be visually compared through the display device, and the dot form difference of the amplified standard sample sheet and the amplified printing sample sheet is observed, so that production adjustment is carried out, errors of magnifying experience judgment of the magnifier are reduced, and detection precision is improved.
The image detection can be used for framing and positioning, the consistency of the printing sample and the dot area of the standard sample is ensured, the occurrence of misjudgment is avoided, the detection precision is ensured, the judgment result can be directly output, and the intelligent degree is high.
It should be understood that equivalent alterations and modifications can be made by those skilled in the art according to the technical solution of the present invention and the inventive concept thereof, and all such alterations and modifications should fall within the scope of the appended claims.

Claims (9)

1. A digital dot image detecting apparatus, comprising: a detect platform for placing the printed matter for shoot the printed matter and predetermine regional image and the enlarged site of region and enlarge the display device who shoots the appearance and be used for showing the site and enlarge the image of shooing the appearance and shooting, it is provided with the support to detect bench, the site enlarge shoot appearance slidable set up in on the support to be connected with display device through the data line.
2. The digital dot image detection device according to claim 1, further comprising a first sliding device for controlling the dot magnification camera to move, wherein the first sliding device comprises a first slider, a first slide rail, a screw rod and a motor, the screw rod and the first slide rail are both disposed on the bracket, a part of the first slider is sleeved on the screw rod and is in threaded connection with the screw rod, another part of the first slider is sleeved on the first slide rail and is connected with the dot magnification camera, and the motor is connected with one end of the screw rod.
3. The digital dot image detection device according to claim 2, wherein a second slide rail is disposed on the detection table, a second slide block is disposed on the second slide rail, and the support is disposed on the second slide block.
4. The digital dot image detection device according to claim 1, wherein the detection table is provided with an air suction hole for sucking a printed matter.
5. The digital dot image detection device according to any one of claims 1 to 4, wherein a positioning ruler is arranged on the detection table.
6. The digital dot image detection device according to any one of claims 1 to 4, wherein a view finding positioning line is provided on a shooting lens of the dot magnification shooting device.
7. The digital dot image detection device according to any one of claims 1 to 4, wherein the display device is disposed on the detection table through a support frame, and the display device is rotatably connected to the support frame.
8. The digital dot image detection device according to claim 7, wherein a third slide rail is further disposed on one side of the detection table, a third slide block is disposed on the third slide rail, and the support frame is disposed on the third slide block.
9. A digital dot image detecting device according to claim 7, wherein a non-reflective neutral gray coating is provided on the detecting table.
CN202021216663.4U 2020-06-28 2020-06-28 Digital dot image detection device Active CN212568538U (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202021216663.4U CN212568538U (en) 2020-06-28 2020-06-28 Digital dot image detection device

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202021216663.4U CN212568538U (en) 2020-06-28 2020-06-28 Digital dot image detection device

Publications (1)

Publication Number Publication Date
CN212568538U true CN212568538U (en) 2021-02-19

Family

ID=74612732

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202021216663.4U Active CN212568538U (en) 2020-06-28 2020-06-28 Digital dot image detection device

Country Status (1)

Country Link
CN (1) CN212568538U (en)

Similar Documents

Publication Publication Date Title
TWI225927B (en) Defect inspection system
JP6061851B2 (en) Measuring machine, measuring system, measuring alignment method and measuring alignment program using the same
US8237828B2 (en) Device for inspection of print products
JP2006189421A (en) High-intelligent digital image inspection system and its inspection method
CN110793976B (en) Printing quality detection system and method
US8359976B2 (en) Method and machine for aligning flexographic printing plates on printing cylinders
EP1911588B2 (en) Colour gauge head positioning device
WO2014157042A1 (en) Measuring device, measurement method, information processing device, and measurement program
US20100039510A1 (en) Method and DEVICE for PRINT INSPECTION
EP0860277A1 (en) A system and method for registration control on-press during press set-up and printing
US20020026879A1 (en) System and method for registration control on-press during press set-up and printing
CN111999312A (en) Digital dot image detection device and detection method
CN212568538U (en) Digital dot image detection device
JP2016206760A (en) Color discrimination method and color discrimination device, as well as printer color tone control method
CN107650508B (en) A kind of machine vision method of offset printing process control
JP2008541304A (en) Method and apparatus for measuring the quality of a printed image
US7339705B2 (en) Apparatus for and method of making measurement on printed sheet
KR20140100756A (en) Measurement Method of Surface Behavior and Sizing Degree for Paper, and Its Measuring Apparatus
CN115420746A (en) Quality detection method, quality detection device and quality detection equipment for printed parts
CN108389182A (en) A kind of picture quality detection method and device based on deep neural network
JP3065071B1 (en) Printing inspection equipment
JP2019215348A (en) Image inspection robot
DE102012207226B4 (en) Apparatus for analyzing a printed copy
US8488220B1 (en) Method and apparatus for calibrating imaging equipment
JP3508659B2 (en) Video extensometer

Legal Events

Date Code Title Description
GR01 Patent grant
GR01 Patent grant