WO2009143731A1

WO2009143731A1 - An anti-forgery system and its method for identifying the truth of an object by verifying a micro-code and a verification code

Info

Publication number: WO2009143731A1
Application number: PCT/CN2009/071350
Authority: WO
Inventors: 何登科
Original assignee: 北京华旗资讯数码科技有限公司
Priority date: 2008-05-27
Filing date: 2009-04-20
Publication date: 2009-12-03

Abstract

An anti-forgery certificate for identifying the truth of an object by verifying a micro-code and a verification code is provided. The verification code and the corresponding micro-code for identifying the truth of an object are both printed on the surface of the anti-forgery certificate, the micro-code consists of a plurality of micro-image cells, every kind of combination of the micro-image cells corresponds to a micro-code and forms a mini-image which is invisible by naked eyes. The micro-code can be decoded to produce an unique information code which is the same with the verification code printed on the surface of the anti-forgery certificate.

Description

Anti-counterfeiting system and method for verifying authenticity by verifying micro image coding and verification code

[1] The present invention relates to an anti-counterfeiting system and method for verifying authenticity by examining miniature image encoding and verification codes

In particular, it relates to an anti-counterfeiting system and method for printing a matching miniature image encoding and verification code, and verifying whether the micro-image encoding and the verification code are matched to match the authenticity.

[2] Background Art

[3] Among the existing anti-counterfeiting technologies, such as ID cards, passports and other documents, the main anti-counterfeiting measures are as follows

1) The more common way is to set the laser holographic pattern on the document. The disadvantage of this kind of anti-counterfeit identification that is recognized by the human eye is that it can be faked and faked by using similar equipment, and it is impossible to distinguish between true and false, not only the anti-counterfeiting function. Strong, and the cost is extremely high; 2) The visual reading information of the surface anti-counterfeiting identification of the document uses an intuitive physical anti-counterfeiting method, and the security point level is managed according to the level. The disadvantage is that it is easy to leak and the anti-counterfeiting method uses common security and a little. After being broken, the whole line is lost; 3) The video reading information and the encryption point are stored in the IC chip integrated with the certificate. The disadvantage of this method is that once the chip is damaged, the machine-readable anti-counterfeiting identification function of the document is invalid. It needs to be queried through the network to the original database, which is inconvenient to query, especially when it is unable to connect with the network, it will be difficult to check. In addition, the cost of the IC card chip is extremely high.

[4] Among the existing anti-counterfeiting technologies, there is also a method for encoding micro-hole anti-counterfeiting. Please refer to Chinese Patent Application No.: 99100515.5, which uses a coded version (microporous master) as a microscopic particle barrier layer. Heavy-charged particle irradiation, in the inspection of each mark, through the micro-pore distribution and the coded version of the micro-pore distribution to identify the authenticity, but this anti-counterfeiting technology has the disadvantage that the micro-hole is also easy to copy, and anti-counterfeiting function Not strong.

[5] In addition, in the prior art, the micro image coding technology for reading the surface of an object by using an optical reading device has become increasingly mature. Please refer to the Chinese invention patent of Patent No. ZL02122633.4, the invention name is: Method for producing image index And a processing system for applying image indicators, the patent discloses in detail a device for recognizing miniature image coding, which can set a dot matrix with a maximum of 13950 black dots per square centimeter, so that it cannot be identified without special equipment. The composition of its image coding has a tendency to be easily used by ordinary people. The characteristics of the identification.

[6] Summary of the invention

[7] The object of the present invention is to provide a new anti-counterfeiting system and method for verifying the authenticity of a micro image by verifying the micro image encoding and verification code. The technical problem to be solved is that the surface of the anti-counterfeiting certificate is not easily recognized and copied by the human eye. The image is encoded and verified by the human eye, and the authenticity is determined by checking whether the image code printed on the security certificate matches the verification code.

[8] The object of the present invention and solving the technical problem thereof are achieved by the following technical solutions: An anti-counterfeiting certificate for verifying the authenticity of a miniature image encoding and verification code according to the present invention, which is used for surface printing a verification code for verifying the authenticity of the item to be inspected and a miniature image code corresponding to the verification code, the miniature image coding being composed of a plurality of micro image units, and distinguishing by a combination of a plurality of micro image units in each micro image coding Different miniature image encodings, and the combination of the plurality of micro image units forms a microscopic image that cannot be recognized by the human eye; the information code uniquely obtained by decoding the micro image encoding is the same as the verification code printed on the surface of the anti-counterfeit certificate.

[9] An anti-counterfeiting system for matching anti-counterfeiting using miniature image encoding and verification code according to the present invention, comprising an anti-counterfeiting certificate, surface printing a verification code for verifying the authenticity of the item to be inspected, and a miniature image encoding corresponding to the verification code The micro image coding is composed of a plurality of micro image units, and different micro image coding is distinguished by a combination of a plurality of micro image units in each micro image coding, and the combination of the plurality of micro image units forms a human eye. A small image that cannot be recognized, the information code obtained by decoding the unique image code is matched with the verification code printed on the surface of the security certificate; the optical module is used to obtain the optical image of the surface microscopic magnification of the security certificate; the image sensor, the optical module The acquired optical image is generated as a digital image; the image recognition processing unit picks up the miniature image code from the digital image generated by the image sensor, and decodes the miniature image into a unique information code corresponding thereto; and an output unit for the miniature image Information code output obtained after code decoding; control Block receives image identification information code output from the processing unit, and controls the output unit outputs.

[10] A method for authenticating a micro image encoding and verification code according to the present invention, comprising the steps of: printing a verification code representing the item to be inspected on the surface of the security certificate and matching the verification code Miniature image coding, which is a micro-pattern array formed by combining a plurality of micro-image units and which is not recognized by the human eye, and the micro-image coding is decoded to obtain a unique information code. Corresponding to the above verification code matching; the optical module obtains the optical image after microscopically magnifying the surface of the anti-counterfeit certificate, and the optical image is generated as a digital image by the image sensor; the image recognition processing unit checks the digital image generated by the image sensor Whether there is a miniature image encoding; if there is a miniature image encoding in the digital image, the micro image is picked up and decoded into an information code corresponding thereto, and the control module controls the output unit to output the information code; the information code output by the output unit is The verification code printed on the surface of the anti-counterfeiting certificate is compared. If the information code and the verification code match, the anti-counterfeiting certificate is true. If they do not match, the anti-counterfeiting certificate is false.

[11] The technical solution as described above, the present invention has the following advantages by checking the micro image encoding and verification code to identify the authenticity of the anti-counterfeiting system and the method thereof:

[12] The invention detects the authenticity of the anti-counterfeiting system by detecting the micro image encoding and verification code to obtain the micro image encoding of the surface of the anti-counterfeit certificate, and then decoding the micro image to obtain the information code, and then the information code and the anti-counterfeiting. The verification code printed on the surface of the certificate is checked, and the authenticity is checked according to the verification result. In the method of the present invention, the anti-counterfeiting certificate is made of any object that can be printed with a miniature image, or the object to be inspected directly printed on the surface with a miniature image, and the printed micro image encoding only needs to be printed. Therefore, the cost is low. In addition, the anti-counterfeiting function can be quickly realized by printing the micro image coding on the surface of the object to be inspected without the anti-counterfeiting.

[13] The above-mentioned miniature image coding is composed of extremely small micro image units, so that it does not affect the visual effect of other graphic characters printed on the surface of the anti-counterfeit certificate, and can ensure that ordinary people cannot use without using special instruments. Distinguishing the graphic composition of the miniature image encoding to ensure the security of the miniature image encoding, and in the case of large-area damage on the surface of the security certificate, the miniature image encoding and recognition device can still pass through the extremely small undamaged portion. Get miniature image encoding to check the authenticity.

[14] The above miniature image coding is extremely small, and each micro image coding is composed of a plurality of micro image units, and each micro image coding is distinguished by a combination of micro image units, and each micro image unit has at least a diameter. As small as 40μηι, if 16 micro image units are used to form a miniature image coding, 7 micro image units are used to locate the micro image coding, and 9 micro image units are used to form a 3x3 planar two-dimensional state area array. 4 ⁹ (= 262144) different combinations of states, corresponding to 262,144 different values that can define different product check codes, which can be retrieved from the 262,144 state combinations, to correspond to the Unicode code structure 65,536 code positions belonging to a Chinese character, the rest The state combination can be reserved for other purposes. It can be seen that the micro image coding is not recognized by the naked eye, and the micro image unit array is combined in various ways, so it is very suitable for use as an anti-counterfeiting authentication, and the micro image coding can also be printed. The ink used is distinguished from the ink of other parts of the printing, and the micro image encoding is obtained by filtering the filter of the micro image encoding and recognizing device, so that the micro image encoding printed on the anti-counterfeiting certificate of the present invention must have a special light source illumination at the same time. The high-magnification micro-amplification, the specific filter filtering, etc. are all available, and the protection of the miniature image encoding as an anti-counterfeiting mark is further realized.

[15] The invention adopts a method of directly reading the micro image coding printed on the surface of the anti-counterfeit certificate, so that the identification speed is fast, and the inspection work of a large number of items to be inspected is completed in a short day, and The query of the verification code visible in the eye can also query part of the product information, such as product batch, sales time, etc., and the verification code is set on the anti-counterfeit certificate in anti-counterfeiting mode, which makes the security certificate non-replicable. .

[16] BRIEF DESCRIPTION OF THE DRAWINGS

1 is a structural block diagram of an anti-counterfeiting system for matching anti-counterfeiting using micro image encoding and verification code according to the present invention.

2 is a schematic view of the anti-counterfeiting certificate of the present invention applied to a wine bottle.

[19] FIG. 3 is a schematic diagram of printing multiple sets of miniature image codes on the anti-counterfeiting certificate of the present invention.

[20] FIG. 4 is a schematic diagram of a micro image unit array combining structure in micro image encoding.

[21] FIG. 5 is a schematic diagram of a state area setting mode of micro image encoding.

[22] FIG. 6 is a flow chart of a method for authenticating a miniature image encoding and verification code to identify authenticity.

[23] Specific implementation

[24] In order to further explain the technical means and efficacy of the present invention for achieving the intended purpose, the following uses the micro image coding and the verification code to match the anti-counterfeiting according to the present invention with reference to the accompanying drawings and preferred embodiments. The anti-counterfeiting system, its specific implementation, structure, features and functions, are described in detail later.

[25] Please refer to FIG. 1 , which is a structural block diagram of an anti-counterfeiting system for matching anti-counterfeiting using micro image coding and verification code, the micro image coding anti-counterfeiting system includes a micro image coding recognition device and an anti-counterfeiting certificate, and an anti-counterfeiting certificate surface printing There is a miniature image encoding for representing the item to be inspected and a verification code corresponding to the miniature image encoding, the miniature image encoding being composed of a plurality of micro image units, and combining the plurality of micro image units in each mini image encoding Distinguishing different miniature image encodings, and the combination of the plurality of micro image units forms a microscopic image that is not recognized by the human eye; the micro image encoding is decoded. The only information code obtained is the same as the verification code printed on the surface of the security certificate. The micro image code printed on each security certificate is one-to-one corresponding to the verification codes of different items to be inspected, and each item to be inspected preferably has a unique verification code.

[26] Specifically, the above-mentioned miniature image coding is performed by combining and decoding a plurality of micro image units, that is, first combining various micro image units and different information codes according to a set combined array manner. In one correspondence, the image recognition processing unit decodes the micro image encoding according to the combined array shape of the micro image units.

[27] The above micro image encoding and recognizing device comprises: an optical module for acquiring an optical image of a microscopic magnification of an anti-counterfeit certificate surface; an image sensor for generating an optical image acquired by the optical module as a digital image; an image recognition processing unit, the image sensor The generated digital image is picked up by the micro image, and the micro image is encoded and decoded into a unique information code; the output unit is configured to output the information code obtained by encoding and decoding the micro image; and the control module receives the image recognition processing unit. The information code is output, and the output unit is controlled to output it. Specifically, the output unit may be a display module including a display screen, or may be an audio output module including a speaker.

[28] Please refer to FIG. 2, which is a schematic diagram of the anti-counterfeiting certificate of the present invention applied to a wine bottle. The above-mentioned miniature image code 10 is printed on the surface of the anti-counterfeiting certificate 1, and is composed of a plurality of micro-image units 16, and each The combination of the plurality of micro image units 16 in the miniature image encoding 10 distinguishes between the different miniature image encodings 10, and the combination of the plurality of micro image units 16 forms a minute graphic that the human eye cannot recognize. In Fig. 2, the anti-counterfeiting certificate is set on the top of the bottle, or can be set at each position of other items to be inspected, or it can be placed in the box separately. In addition, a verification code 2 is also provided on the bottle for checking by the inspector, and the verification code 2 is a string identical or matching the information code uniquely obtained after decoding by the miniature image encoding 10.

Referring to FIG. 3, FIG. 4, FIG. 5, FIG. 3 is a schematic diagram of printing multiple sets of micro image coding on the anti-counterfeiting certificate of the present invention, and FIG. 4 is a schematic diagram of a micro image unit array combining structure in micro image coding. Fig. 5 is a schematic diagram showing the manner of setting the state area of the micro image coding to clearly illustrate the design of the present invention. The micro image code 10 includes a content data portion 12 and a header portion 14. According to the present embodiment, the content data unit 12 includes nine micro image units composed of nine dots 16, and the area occupied by the content data portion 12 is divided into nine state regions 18, thereby constituting a 3x3 plane two-dimensional. The array of status areas, each of the status areas 18 includes one A dot of 16. According to the design of the present embodiment, a different position of a dot 16 in a state area 18 can be utilized to represent a value in the corresponding index data. Specifically, as shown in FIG. 5, a state area 18 can be equally divided into four virtual areas, and the dots 16 are selectively placed in one of the four virtual areas of the lower right, the lower left, the upper left, and the upper right. To represent four different bit values 00, 01, 10, or 11, respectively. Therefore, the bit values shown in the content data portion 12 of Fig. 4 are combined by the state of the micro image units of the corresponding arrangement relationship in Fig. 6. Since each of the state regions 18 is divided into four virtual regions, when the respective dots 16 are selectively disposed in one of the four virtual regions, the content data portion 12 can be made to have 4 ⁹ (= 262144) state combinations. . According to the above, the micro image encoding is decoded by the placement position of the micro image unit (ie, the dot 16) in different virtual regions, and the setting of the virtual region and the placement position of the micro image unit are uncontrollable by the replica. Therefore, encoding a miniature image composed of a plurality of micro image units is extremely non-reproducible.

[30] In the first embodiment of the present invention, the above-described miniature image encoding is printed with ink different from the color of the surface of the security certificate, that is, the ink color used for printing the micro image encoding on the surface of the security certificate is encoded with the printed micro image. The color of the ink is different; the optical module is provided with a lens and a filter, and the lens amplifies the optical image of the surface of the security certificate, and the filter filters the light of the optical image that is different in color from the micro image.

[31] In the second embodiment of the present invention, the micro image encoding described above is printed on the surface of the anti-counterfeiting certificate by a special ink, and the light wave reflected by the special ink under the illumination of the specific wavelength is different from the ordinary ink; The information other than the micro image coding printed on the surface of the anti-counterfeit certificate is printed with ordinary ink; the optical module is provided with a special light source, a filter and a lens, and the special light source irradiates light of a specific wavelength on the surface of the anti-counterfeit certificate, and the lens will have an anti-counterfeit certificate surface. The optical image is magnified, and the filter filters the light outside the wavelength band of the special ink reflected by the special light source.

[32] The above-mentioned anti-counterfeit certificate can be provided with a concealed area printed with ordinary ink on the surface, and the micro image code representing the item to be inspected is printed in a concealed area with a special ink; the color of the ordinary ink is the same as the color of the special ink, thereby miniaturizing The image coding is mixed with the common ink printing portion by the same color, so that the ordinary user can obtain the micro image unit array structure of the micro image coding by using the microscopic magnification device.

[33] In the third embodiment of the present invention, the above-described miniature image encoding is an absorption ink that absorbs a large amount of infrared light. Printing on the surface of the anti-counterfeit certificate; printing the micro-image-encoded anti-counterfeit certificate on the surface of the non-absorbent ink that does not absorb infrared light to print information other than the micro-image encoding; the optical module is provided with an infrared light source, a filter and a lens, the infrared The light source illuminates the surface of the anti-counterfeit certificate with the infrared light, and the lens amplifies the optical image on the surface of the anti-counterfeit certificate, and the filter filters the light wave at a frequency other than the infrared band. Specifically, the above-mentioned absorbing ink is preferably a carbon-containing ink.

[34] The above-mentioned anti-counterfeit certificate is printed with a non-absorbent ink on the surface with a concealed area, and the micro-image code representing the object to be inspected is printed to absorb the ink in the concealed area, and the color of the non-absorbent ink is the same as the color of the absorbed ink, thereby miniaturizing The image-encoded and non-absorbent ink-printed portions are mixed together in the same color, so that an ordinary user can obtain a micro-image unit array structure in which micro image coding cannot be obtained by using a microscopic magnification device.

[35] The above verification code can be printed outside the concealed area, or printed in the concealed area, and printed in a color different from the ink color of the concealed area. In addition, it is preferable that the verification code is disposed on the surface of the anti-counterfeit certificate in an anti-counterfeiting manner, and the anti-counterfeiting method includes setting the verification code on the surface of the anti-counterfeiting certificate as a watermark, or printing the verification code on the surface of the anti-counterfeiting certificate with the ink containing the ultraviolet phosphor.

[36] Please refer to FIG. 3, which is a flow chart of the method for authenticating the micro image coding and verification code to verify the authenticity of the present invention. The method is as follows:

[37] printing a verification code representing the item to be inspected and a miniature image code matching the verification code on the surface of the security certificate, the miniature image coding being a micro graphic array formed by combining a plurality of micro image units and being unrecognizable by the human eye The unique obtained information code after the decoding of the miniature image code is matched with the verification code;

[38] The optical module obtains an optical image of the surface of the anti-counterfeit certificate microscopically amplified, and the optical image is generated by the image sensor as a digital image;

[39] The image recognition processing unit checks whether there is a micro image encoding from the digital image generated by the image sensor, and if there is no micro image encoding in the digital image, waits for the image sensor to transmit a digital image having a miniature image encoding, or through an output unit Informing that the security certificate does not contain a valid miniature image code;

[40] If there is a miniature image encoding in the digital image, the micro image is picked up and decoded into an information code corresponding thereto, and the control module controls the output unit to output the information code; [41] The information code outputted by the output unit is compared with the verification code printed on the surface of the anti-counterfeit certificate. If the information code and the verification code match, the anti-counterfeiting certificate is true. If they do not match, the anti-counterfeiting certificate is false.

Claims

Claim

[1] An anti-counterfeiting certificate for verifying authenticity by verifying micro image encoding and verification code, wherein: the anti-counterfeiting certificate surface prints a verification code for verifying the authenticity of the item to be inspected and a miniature image corresponding to the verification code Encoding, the miniature image encoding is composed of a plurality of micro image units, and different micro image encodings are distinguished by a combination of a plurality of micro image units in each micro image encoding, and the combination of the plurality of micro image units forms a human eye A small figure that cannot be recognized; the information code that can be uniquely obtained by decoding the micro image code is the same as the verification code printed on the surface of the security certificate.

[2] The anti-counterfeiting certificate for verifying authenticity by verifying micro image coding and verification code according to claim 1

The micro image encoding is printed on the surface of the anti-counterfeiting certificate by using a special ink, and the light wave reflected by the special ink under the illumination of the specific wavelength is different from the ordinary ink; the surface of the anti-counterfeiting certificate is made of ordinary ink. Printing information other than micro image encoding, the surface of the anti-counterfeiting certificate does not contain special ink except micro image encoding.

[3] An anti-counterfeiting certificate for verifying authenticity by verifying micro image encoding and verification code according to claim 2

The feature is that: the micro image encoding is printed on the surface of the anti-counterfeiting certificate by a large amount of absorption ink that absorbs infrared light.

[4] An anti-counterfeiting certificate for verifying authenticity by verifying micro image encoding and verification code according to claim 3.

It is characterized in that: the absorption ink is a carbon-containing ink.

[5] An anti-counterfeiting certificate for verifying authenticity by verifying micro image encoding and verification code according to claim 2

And characterized in that: the surface of the anti-counterfeiting certificate is printed with a concealed area by a common ink, and the micro-image code is printed in a concealed area with a special ink; the color of the ordinary ink is the same as the color of the special ink.

[6] The anti-counterfeiting certificate for verifying authenticity by verifying micro image coding and verification code according to claim 5

And characterized in that: the verification code is printed on the concealment area and printed in a color different from the color of the concealed area ink.

[7] The anti-counterfeiting certificate for verifying the authenticity of the micro image encoding and the verification code according to claim 1

The feature code is: wherein the verification code is set on the surface of the security certificate for the anti-counterfeiting mode.

[8] The anti-counterfeiting certificate for verifying authenticity by verifying micro image coding and verification code according to claim 7

The feature is that the verification code is set on the surface of the security certificate in the form of a watermark.

[9] The anti-counterfeiting certificate for verifying authenticity by verifying micro image coding and verification code according to claim 7

And characterized in that: the verification code is printed with an ink containing an ultraviolet phosphor.

[10] An anti-counterfeiting system using micro image coding and verification code matching anti-counterfeiting, characterized in that it comprises an anti-counterfeiting certificate, a surface verification printing verification code for verifying the authenticity of the item to be inspected, and a miniature image coding corresponding to the verification code, The miniature image coding is composed of a plurality of micro image units, and different micro image coding is distinguished by a combination of a plurality of micro image units in each micro image coding, and the combination of the plurality of micro image units is not recognized by the human eye. The micro-image is encoded, and the information code obtained by decoding is matched with the verification code printed on the surface of the anti-counterfeit certificate; the optical module is used for obtaining the optical image of the microscopic magnification of the surface of the anti-counterfeit certificate;

An image sensor that generates an optical image acquired by the optical module as a digital image;

The image recognition processing unit picks up the micro image code from the digital image generated by the image sensor, and decodes the micro image into the information code corresponding thereto;

An output unit, configured to output an information code obtained by encoding and decoding the micro image; and a control module that receives the information code output by the image recognition processing unit and controls the output unit to output the information code.

[11] The anti-counterfeiting system for matching anti-counterfeiting using micro image encoding and verification code according to claim 10, wherein: said micro image encoding is printed on a surface of an anti-counterfeiting certificate by a special ink, the special ink being at a specific wavelength The light wave reflected by the light irradiation is different from the ordinary ink; the surface of the anti-counterfeit certificate is printed with information other than the miniature image code by the ordinary ink, and the surface of the anti-counterfeit certificate does not contain the special ink except the micro image code.

[12] The anti-counterfeiting system for matching anti-counterfeiting using micro image encoding and verification code according to claim 11, wherein: the optical module is provided with a special light source, a filter and a lens, and the special light source will light of a specific wavelength Irradiated on the surface of the anti-counterfeit certificate, the lens magnifies the optical image on the surface of the anti-counterfeit certificate, and the filter filters the light outside the band of the light reflected by the special ink under the illumination of the special light source.

[13] A method for authenticating a micro image by verifying a miniature image encoding and verification code, characterized in that it comprises the following steps:

Printing a verification code representing the item to be inspected on the surface of the security certificate and a miniature matching the verification code Image coding, the micro image coding is a micro graphic array formed by combining a plurality of micro image units and being unrecognizable by the human eye, and the only obtained information code after the decoding of the micro image encoding is matched with the verification code;

The optical module obtains an optical image obtained by microscopically magnifying the surface of the anti-counterfeit certificate, and the optical image is generated by the image sensor as a digital image;

The image recognition processing unit checks whether there is a micro image encoding from the digital image generated by the image sensor;

If there is a miniature image encoding in the digital image, the micro image is picked up and decoded into an information code corresponding thereto, and the control module controls the output unit to output the information code; and the information code outputted by the output unit and the surface of the security certificate are verified. The code is compared. If the information code and the verification code match, the security certificate is true. If they do not match, the security certificate is false.

[14] A method for authenticating a micro image by verifying a miniature image encoding and verification code according to claim 13.

The feature is that: the micro image code does not exist in the digital image, and then waits for the image sensor to transmit the digital image with the miniature image code, or the output unit notifies that the security certificate does not contain the effective micro image code.

[15] A method for authenticating a micro image by verifying a miniature image encoding and verification code according to claim

The micro image encoding is composed of a plurality of micro image units, and different micro image encodings are distinguished by a combination of a plurality of micro image units in each mini image encoding.

[16] A method for authenticating a micro image by verifying a miniature image encoding and verification code according to claim

[17] A method for authenticating a micro image by verifying a miniature image encoding and verification code according to claim 16.

The optical module is provided with a special light source, a filter and a lens. The special light source illuminates a specific wavelength of light on the surface of the anti-counterfeit certificate, and the lens amplifies the optical image on the surface of the anti-counterfeit certificate, and the filter applies the special ink. Light filtering outside the wavelength band of light reflected by a special light source.