Method for realizing display of various encrypted information through laser-induced anion exchange

Abstract

The invention discloses a method for realizing display of various encrypted information through laser-induced anion exchange. The method comprises the following steps: mixing CsPbBr3 quantum dots and PDMS (Polydimethylsiloxane) to prepare a composite film; designing an encrypted information pattern with confusion information; different degrees of anion exchange are realized by utilizing an anion exchange solution and regulating and controlling laser parameters, and an encrypted information pattern with confusion information is completed on the composite film; and finally, an ultraviolet lamp, a 470 + / -10nm narrow-band filter and a smart phone are used for reading and decrypting encrypted information. The method is easy and convenient to operate, the risk of information counterfeiting is remarkably reduced, the hierarchy and complexity of information encryption are improved, and the efficient encryption / decryption function is achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of information encryption, and in particular to a method for realizing display of multiple encrypted information by laser-induced anion exchange. Background Art

[0002] In the digital age, the massive growth of information has greatly changed the way people live. However, along with the information explosion comes the proliferation of false information and counterfeit goods that are difficult to distinguish between true and false, which pose a serious threat to human safety and social stability. Therefore, it is particularly urgent to develop advanced information encryption and anti-counterfeiting technologies. Among many technologies, optical anti-counterfeiting, especially fluorescent anti-counterfeiting technology, stands out due to its advantages such as high visibility, simple design, low manufacturing cost and convenient verification.

[0003] Advances in optical anti-counterfeiting technology have provided new methods for improving the storage capacity and encryption security of optical information. Perovskite quantum dots have become a rising star in the field of optical information encryption due to their excellent optical properties, such as high fluorescence quantum yield, wide luminescence spectrum range, and adjustable luminescence color. A significant advantage of perovskite quantum dots is that they can achieve precise control of the luminescence wavelength through anion exchange technology. In particular, laser-triggered liquid-phase anion exchange technology can finely adjust the fluorescence peak position of perovskite quantum dots by precisely controlling laser parameters. This precise control not only improves the information accuracy of optical encryption, but also significantly improves the security level, effectively preventing information or data from being forged.

[0004] The development of this technology indicates that the application of optical encryption technology in the field of information security will be more extensive and in-depth in the future, especially in the fields of financial transactions, military communications and personal privacy protection that require high security. With the continuous advancement and innovation of optical encryption technology, its application in the fields of information security and anti-counterfeiting is expected to continue to expand, providing strong technical support for protecting information security in the digital age. Summary of the invention

[0005] The present invention aims to propose a method for realizing the display of multiple encrypted information by laser-induced anion exchange, which is based on the design and manufacture of quantum dot composite film encryption methods for various information storage scenarios.

[0006] In a first aspect, the present invention provides a method for realizing multiple encrypted information display by laser-induced anion exchange, which specifically comprises the following steps:

[0007] Step 1: Mix the CsPbBr3 quantum dot solution with PDMS and cross-link to form a composite film;

[0008] Step 2: Design an encrypted information pattern including obfuscated information and correct information, and import the pattern information into the EzCad2 software as the planning path of the laser;

[0009] Step 3: placing the composite film in an anion exchange solution, controlling the laser path through software, and performing laser-induced anion exchange to achieve patterning of the encrypted information;

[0010] Step 4: Use ultraviolet light to illuminate the patterned encrypted information to make it emit fluorescence, and use a 470±10nm narrow-band filter to filter the light, and finally obtain the encrypted information pattern after filtering;

[0011] Step 5: Read the encrypted information pattern obtained in step 4.

[0012] Preferably, the encrypted information includes QR code information and digital information.

[0013] Preferably, in step 1, a curing agent is added to the PDMS and CsPbBr3 quantum dot solution, and the solution is fully stirred and then coated on a glass substrate, and a composite film is obtained after annealing, wherein the mass of the curing agent is 0.1 times the mass of PDMS, the volume ratio of PDMS to the CsPbBr3 quantum dot solution is 1:1, the concentration of the CsPbBr3 quantum dot solution is 67.5 mg / ml, and the thickness of the composite film is controlled at 200-300 μm.

[0014] Preferably, in step 2, an encrypted information pattern including obfuscated information and correct information is designed, and the specific process is: design a two-dimensional code information pattern storing correct information, and add the obfuscated information pattern therein to obtain the encrypted information pattern.

[0015] Preferably, in step 2, an encrypted information pattern including obfuscated information and correct information is designed, and the specific process is: converting the correct digital information into binary form, and determining the patterns represented by "1" and "0" respectively, and adding the obfuscated information pattern thereto to obtain the encrypted information pattern.

[0016] Preferably, in step 3, 1% oleylamine and 1% oleic acid are added to a mixture of chloroform and toluene in a volume ratio of 1:1 to serve as an anion exchange solution.

[0017] Preferably, in step 3, the laser path is controlled by EzCad2 software, and different laser parameters are used for laser-induced anion exchange to achieve patterning of the encrypted information, wherein the correct information is scanned using the following laser parameters: wavelength of 532nm, scanning speed of 8mm / s, frequency of 50Hz, and laser power of 580μJ; the obfuscated information is scanned using the following laser parameters: wavelength of 532nm, scanning speed of 8mm / s, frequency of 50Hz, and laser power of 80μJ.

[0018] Preferably, in step 5, the encrypted information pattern is read, and when the encrypted information is a QR code, the encrypted information pattern is scanned by a smart device to read the information.

[0019] Preferably, in step 5, the encrypted information pattern is read. When the encrypted information is digital information, the binary system is converted into the decimal system according to the patterns represented by "1" and "0" respectively, and the information is read.

[0020] Compared with the prior art, the present invention has the following beneficial effects:

[0021] (1) The present invention utilizes the filter's specific transmission, reflection or absorption characteristics to selectively pass light within certain wavelength ranges while blocking light of other wavelengths, accurately controlling the display of the encrypted pattern and improving the accuracy of the encryption process. (2) The anion exchange technology proposed in the present invention can achieve precise control of the luminescent wavelength by adjusting the laser parameters, thereby creating a unique, accurate, and difficult-to-copy luminescent pattern.

[0022] (3) The patterning method proposed in the present invention can precisely control the spatial position of anion exchange by changing the laser focusing position, and can achieve fast and accurate patterning without a mask plate, which greatly reduces the complexity of the encryption operation process.

[0023] (4) The two-dimensional code used in the present invention has a wide range of application scenarios. As encrypted information, it will not attract special attention and has a strong hiding effect.

[0024] (5) The equipment used in the present invention is cheap, and the optical path constructed is simple and easy to understand.

[0025] (6) The invention has strong scalability: 1) by changing the type of halogenated alkane, a wider spectrum tuning can be achieved, which provides the possibility for full-color encryption applications; 2) the prepared composite film is ultra-flexible and can be arbitrarily bent and folded into different shapes. After multiple bending and folding, it can still maintain a high photoluminescence (PL) intensity; and the stability of the perovskite coated with PDMS is greatly improved, so the technology has strong environmental adaptability. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 Schematic diagram of the formation of CsPbBr3-PDMS composite membrane.

[0027] Figure 2 Actual pictures of CsPbBr3-PDMS composite membrane under (a) natural light and (b) ultraviolet light.

[0028] Figure 3The designed (a) QR code with correct information and (b) QR code with obfuscated information added, where the red part is the obfuscated information pattern.

[0029] Figure 4 Schematic diagram of laser-induced anion exchange.

[0030] Figure 5 It is a two-dimensional code with obfuscated information prepared by laser induction under ultraviolet light.

[0031] Figure 6 Schematic diagram of the decryption process.

[0032] Figure 7 Under ultraviolet light, a 470±10nm narrow-band filter is used to filter out the correct information of the QR code that confuses the information.

[0033] Figure 8 The designed (a) binary encryption pattern with obfuscation information and (b) binary encryption pattern without obfuscation information, where the light blue part is the obfuscation information.

[0034] Fig. 9 It is a binary encrypted information pattern with obfuscated information prepared by laser induction under ultraviolet light.

[0035] Fig.10 In order to filter out the correct binary encrypted information pattern that obfuscates the information under ultraviolet light, a 470±10nm narrow-band filter is used.

[0036] Fig.11 The patterning of the film induced under the same laser parameters, where (a) is the actual picture under ultraviolet light irradiation, and (b) is the image taken after using a 470±10nm narrow band filter under ultraviolet light irradiation. DETAILED DESCRIPTION

[0037] The present invention is further explained below in conjunction with specific test examples. It should be understood that these embodiments are only used to illustrate the present invention and are not used to limit the scope of the present invention. After reading the present invention, various equivalent forms of modifications to the present invention by those skilled in the art all fall within the scope defined by the claims attached to this application.

[0038] It should be noted that the terms such as "upper", "lower", "left", "right", "middle", etc. cited in this specification are only for the convenience of description and are not used to limit the scope of implementation. Changes or adjustments to their relative relationships should be regarded as the scope of implementation of this application without substantially changing the technical content.

[0039] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which this application belongs; the term "and / or" used herein includes any and all combinations of one or more of the associated listed items.

[0040] If the specific conditions are not specified in the examples, the experiments were carried out under conventional conditions or conditions recommended by the manufacturer. If the manufacturers of the reagents or instruments are not specified, they are all conventional products that can be purchased commercially.

[0041] As used herein, the term "about" is used to provide flexibility and imprecision associated with a given term, measurement or value. The degree of flexibility for a particular variable can be easily determined by one skilled in the art.

[0042] As used herein, the term "at least one of" is intended to be synonymous with "one or more of." For example, "at least one of A, B, and C" expressly includes only A, only B, only C, and combinations of each thereof.

[0043] In the embodiment of the present invention, a green composite film was first prepared using CsPbBr3 quantum dots and PDMS, and then a blue encrypted pattern with obfuscated information (due to the chloride ions in the anion exchange solution) was prepared using the laser-induced anion exchange method. Finally, three decryption methods (ultraviolet light, 470±10nm narrowband filter and smart phone) were combined to decrypt the information. The specific principle is: the green composite film is immersed in an anion exchange solution whose main component is chloroform, and the solution is irradiated with a 532nm laser to generate Cl - , so that the green light in the composite film is gradually converted into blue light with a wavelength of 471nm, and a patterned QR code with correct information is obtained. Then, the composite film is irradiated under different laser parameter conditions, so that its green light is gradually converted into blue light with a wavelength of 500nm, and the patterning of obfuscated information is obtained. Finally, the encrypted pattern is irradiated with ultraviolet light and the obfuscated information in the encrypted pattern is filtered out using a 470±10nm narrow-band filter. A smartphone is used to take a photo and decrypt it to obtain the correct encrypted information.

[0044] The CsPbBr3 quantum dot solution of the present invention can be commercially available or homemade according to literature. The CsPbBr3 quantum dot solution involved in the following embodiments is homemade according to the literature Precise Laser-Modulated Anion Exchange on Ultraflexible Perovskite Films for Multicolor Patterns.

[0045] Example 1

[0046] Example 1 is to use QR code to realize encrypted information storage. By storing the information in the correct QR code and adding obfuscated information to it, the encrypted information is hidden. The specific steps are as follows. The main experimental device and operation process are as follows: Figure 1 , Figure 4 and Figure 6 As shown, the laser outputs 532nm pulsed laser, the material compounded with the film is PDMS, the halogen ion solution is chloroform, and the perovskite quantum dots are CsPbBr3.

[0047] Step 1: Mix the CsPbBr3 quantum dot solution with PDMS to form a composite film. The process diagram is as follows: Figure 1 As shown, the specific steps are as follows:

[0048] Step 1.1: First, the glass slide was ultrasonicated in deionized water, isopropanol and acetone for 10 min in sequence, then dried with nitrogen and treated with UV for 20 min.

[0049] Step 1.2: Put the curing agent with a mass of about 0.1 times that of PDMS into the mixture of PDMS and CsPbBr3 quantum dot solution (the volume ratio of PDMS to quantum dot solution is 1:1, and the concentration of quantum dot solution is 65.6 mg / ml), stir it thoroughly until it is uniform, and then remove the bubbles with vacuum suction.

[0050] Step 1.3: Place the treated glass slide on the scraper, drop an appropriate amount of CsPbBr3-PDMS solution on the glass slide, and then scrape it evenly with the scraper.

[0051] Step 1.4: Place the coated film on a hot plate and anneal at 150°C for 3 hours. Finally, a CsPbBr3-PDMS composite film is prepared. The actual picture of the film in normal state is as follows Figure 2 As shown in (a) of FIG. 1 , it emits green light under the irradiation of ultraviolet light. Figure 2 As shown in (b) in .

[0052] Step 2: Use QR code to store encrypted information and design a QR code information pattern that stores the correct information "laser".

[0053] Step 2.1: Enter the correct information "laser" in the QR code generator to generate the corresponding QR code, such as Figure 3 As shown in (a) in .

[0054] Step 2.2: Convert the QR code image into a corresponding vector image, add obfuscation information into it using Adobe Illustrator software, and then generate an image with obfuscation information, such as Figure 3As shown in (b), the red part is the designed obfuscation information.

[0055] Step 2.3: Import the pattern information generated in step 2.2 into the EzCad2 software as the planning path for the laser.

[0056] Step 3: Place the composite film in an anion exchange solution, control the laser path through EzCad2 software, and perform laser-induced anion exchange to achieve patterning of the encrypted information. Figure 4 As shown,

[0057] Step 3.1: Prepare anion exchange solution. The specific operation is as follows: In a glass dish, add 1% oleylamine and 1% oleic acid (volume ratio is 1:1) to a mixture of chloroform (as a chlorine source) and toluene in a volume ratio of 1:1 to obtain anion exchange solution, and immerse the CsPbBr3-PDMS composite membrane in the anion exchange solution.

[0058] Step 3.2: Control the laser path through EzCad2 software to perform laser-induced anion exchange to achieve Figure 3 For the patterning of the image in (a), the following laser parameters were used: wavelength of 532 nm, scanning speed of 8 mm / s, frequency of 50 Hz, and laser power of 580 μJ.

[0059] Step 3.3: Use EzCad2 software to control the laser path again and perform laser-induced anion exchange to achieve Figure 3 The patterning of the red part of the image (b) is done with the following laser parameters: wavelength 532nm, scanning speed 8mm / s, frequency 50Hz, laser power 80μJ. The final image is as follows: Figure 5 The left image shows the light blue part of the image is confusing information, and the rest is correct information. When the image is scanned with a mobile phone, no information can be obtained. Figure 5 The right image of .

[0060] Step 4: Use ultraviolet light, 470±10nm narrowband filter and camera to decrypt. The decryption process diagram is as follows: Figure 6 shown.

[0061] Step 4.1: Under ultraviolet light, use a 470±10nm narrowband filter to filter the QR code image. Patterns with wavelengths outside the 470±10nm range will be filtered out. The final result is a QR code with the correct information. The actual effect of the shot is shown below: Figure 7 As shown in the image on the left.

[0062] Step 5: Read the encrypted information pattern obtained in step 4. Scan it with your mobile phone to get the correct encrypted information - "laser". Figure 7 As shown in the image on the right.

[0063] Example 2

[0064] Embodiment 2 is to use binary to realize the encryption of digital information. By converting digital information into binary form and adding obfuscated information therein, encrypted data is constructed, thereby realizing the hiding and protection of original data information. The specific steps are as follows, wherein the laser outputs 532nm pulsed laser, the material composited with the film is PDMS, the halogen ion solution is chloroform, and the perovskite quantum dot is CsPbBr3.

[0065] Step 1: Same as step 1 in Example 1.

[0066] Step 2: Use binary to encrypt digital information and design a binary encrypted information pattern that includes obfuscated information and correct information.

[0067] Step 2.1: Figure 8 (a) in the figure designs a binary encrypted information pattern based on "circle" and "square" with obfuscated information and correct information. The light blue part is the obfuscated information, and the dark blue part is the correct information. Among them, the "circle pattern" represents the number "1" and the "square pattern" represents the number "0". The patterns represented by the numbers "0" and "1" can also be other patterns, not limited to the above patterns. Among them, the first row of patterns is read as the binary information of "10", which represents the number "2" after conversion to decimal. The following rows of patterns are read in the same way, and finally the wrong information "822198" can be obtained. Figure 8 (b) is the binary encryption pattern after removing the obfuscated information. After reading the first row of patterns, the binary information of "1000" is obtained, which represents the number "8" after conversion to decimal. The following rows of patterns are read in the same way, and finally the correct information "210094" can be obtained.

[0068] Step 2.2: According to the design encryption information idea of ​​step 2.1, import the designed binary encrypted pattern information with obfuscated information and correct information into the EzCad2 software as the planning path of the laser.

[0069] Step 3: placing the composite film in an anion exchange solution, controlling the laser path through EzCad2 software, and performing laser-induced anion exchange to achieve patterning of the encrypted information.

[0070] Step 3.1: Prepare anion exchange solution. The specific operation is as follows: In a glass dish, add 1% oleylamine and 1% oleic acid (volume ratio is 1:1) to a mixture of chloroform (as a chlorine source) and toluene in a volume ratio of 1:1 to obtain anion exchange solution, and immerse the CsPbBr3-PDMS composite membrane in the anion exchange solution.

[0071] Step 3.2: Control the laser path through EzCad2 software to perform laser-induced anion exchange to achieve Figure 8 The patterning of the dark blue pattern (correct digital information) in (a) was performed by scanning with the following laser parameters: wavelength of 532 nm, scanning speed of 8 mm / s, frequency of 50 Hz, and laser power of 580 μJ.

[0072] Step 3.3: Use EzCad2 software to control the laser path again and perform laser-induced anion exchange to achieve Figure 8 The patterning of the light blue pattern (obfuscated information) in (a) was performed using the following laser parameters: wavelength 532nm, scanning speed 8mm / s, frequency 50Hz, laser power 80μJ. The actual effect obtained is shown in the figure below. Fig. 9 The left image of , where the light blue part is confusing information and the other parts are correct information.

[0073] Step 4: Decryption using UV light, 470±10nm narrowband filter and camera equipment.

[0074] Step 4.1: Under ultraviolet light, use a 470±10nm narrowband filter to filter the image in step 3. Patterns with wavelengths outside the 470±10nm range will be filtered out. The final result is binary encrypted pattern information with correct information. The actual effect obtained by shooting is shown in the figure below. Fig.10 As shown in the image on the left.

[0075] Step 5: Read the encrypted information pattern obtained in step 4, such as Fig.10 According to the rule that the "circular pattern" represents the number "1" and the "square pattern" represents the number "0", the binary system is converted into decimal, and the data information obtained is "210094", which is the correct encryption information.

[0076] Comparative Example 1

[0077] The other processes are the same as those in Example 1, except that in step 3, when the composite film is patterned, the same laser parameters are used to pattern the confusing information and the correct information, that is, the following laser parameters are used for scanning: wavelength of 532nm, scanning speed of 8mm / s, frequency of 50Hz, laser power of 580μJ, wherein, Fig.11(a) is a real picture under ultraviolet light. Fig.11 (b) is an image taken under ultraviolet light using a 470±10nm narrow-band filter, in which the confusing information cannot be filtered out.

[0078] The above-mentioned implementation cases are only preferred implementation cases in the present invention, but the implementation methods of the present invention are not limited to the above-mentioned implementation cases. For example, various forms of combinations of the schemes in the embodiments, any other changes, modifications, substitutions, and combinations made without departing from the spirit and principles of the present invention should be equivalent replacement methods and are within the protection scope of the present invention.

Claims

1. A method for realizing multiple encrypted information display by laser-induced anion exchange, characterized in that: The specific steps include: Step 1: Mix the CsPbBr3 quantum dot solution with PDMS and cross-link to form a composite film; Step 2: Design an encrypted information pattern including obfuscated information and correct information, and import the pattern information into the EzCad2 software as the planning path of the laser; Step 3: placing the composite film in an anion exchange solution, controlling the laser path by software, and performing laser-induced anion exchange to achieve patterning of the encrypted information; Step 4: Use ultraviolet light to illuminate the patterned encrypted information to make it emit fluorescence, and use a 470±10nm narrow-band filter to filter the light, and finally obtain the encrypted information pattern after filtering; Step 5: Read the encrypted information pattern obtained in step 4.

2. The method according to claim 1, characterized in that The encrypted information includes QR code information and digital information.

3. The method according to claim 1, characterized in that In step 1, a curing agent is added to the PDMS and CsPbBr3 quantum dot solution, and the mixture is fully stirred and then coated on a glass substrate. A composite film is obtained after annealing, wherein the mass of the curing agent is 0.1 times the mass of PDMS, the volume ratio of PDMS to the CsPbBr3 quantum dot solution is 1:1, the concentration of the CsPbBr3 quantum dot solution is 67.5 mg / ml, and the thickness of the composite film is controlled at 200-300 μm.

4. The method according to claim 1, characterized in that In step 2, an encrypted information pattern including obfuscated information and correct information is designed. The specific process is: design a two-dimensional code information pattern that stores the correct information, and add the obfuscated information pattern therein to obtain the encrypted information pattern.

5. The method according to claim 1, characterized in that In step 2, an encrypted information pattern including obfuscated information and correct information is designed. The specific process is: convert the correct digital information into binary form, determine the patterns represented by "1" and "0" respectively, and add the obfuscated information pattern therein to obtain the encrypted information pattern.

6. The method according to claim 1, characterized in that In step 3, 1% oleylamine and 1% oleic acid are added to a mixture of chloroform and toluene in a volume ratio of 1:1 to serve as an anion exchange solution.

7. The method according to claim 1, characterized in that In step 3, the laser path is controlled by EzCad2 software, and different laser parameters are used for laser-induced anion exchange to achieve patterning of the encrypted information, wherein the correct information is scanned using the following laser parameters: wavelength of 532 nm, scanning speed of 8 mm / s, frequency of 50 Hz, and laser power of 580 μJ; the obfuscated information is scanned using the following laser parameters: wavelength of 532 nm, scanning speed of 8 mm / s, frequency of 50 Hz, and laser power of 80 μJ.

8. The method according to claim 1, characterized in that In step 5, the encrypted information pattern is read. When the encrypted information is a QR code, a smart device is used to scan the encrypted information pattern to read the information.

9. The method according to claim 1, characterized in that In step 5, the encrypted information pattern is read. When the encrypted information is digital information, the binary system is converted into decimal system according to the patterns represented by "1" and "0" respectively, and the information is read.

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