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

Abstract

The application discloses a kind of laser-induced anion exchange realizes the method for displaying multiple encrypted information, and its steps are as follows: CsPbBr3 quantum dot is mixed with PDMS to make composite film;Design encrypted information pattern with confusion information;Different degrees of anion exchange are realized using anion exchange solution and control laser parameters and complete encrypted information pattern with confusion information on composite film;Finally, use ultraviolet lamp, 470±10nm narrow-band filter and smart phone to read and decrypt encrypted information.The application is easy to operate, and significantly reduces the risk of information forgery, improves the level and complexity of information encryption, and realizes efficient encryption / decryption function.

Description

Technical Field

[0001] This invention relates to the field of information encryption technology, and in particular to a method for displaying various encrypted information by laser-induced anion exchange. Background Technology

[0002] In the digital age, the massive increase in information has profoundly changed human lifestyles. However, this information explosion has also brought with it a proliferation of misinformation and counterfeit goods, posing serious threats to human security and social stability. Therefore, the development of advanced information encryption and anti-counterfeiting technologies has become particularly urgent. Among numerous 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 enhancing optical information storage capacity and encryption security. Perovskite quantum dots, due to their superior optical properties such as high fluorescence quantum yield, wide emission spectrum range, and tunable emission color, have become rising stars in the field of optical information encryption. A significant advantage of perovskite quantum dots lies in their ability to precisely control the emission wavelength through anion exchange technology. In particular, laser-triggered liquid-phase anion exchange technology, by precisely controlling laser parameters, can meticulously adjust the fluorescence peak position of perovskite quantum dots. This precise control not only improves the accuracy of optically encrypted information but also significantly enhances the security level, effectively preventing information or data from being forged.

[0004] The development of this technology foreshadows a wider and deeper application of optical encryption in the field of information security in the future, especially in areas requiring high security such as financial transactions, military communications, and personal privacy protection. With the continuous advancement and innovation of optical encryption technology, its application in information security and anti-counterfeiting is expected 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 displaying various encrypted information by laser-induced anion exchange. This method is based on the design and fabrication of quantum dot composite thin films for encryption in various information storage scenarios.

[0006] In a first aspect, the present invention provides a method for displaying various encrypted information by laser-induced anion exchange, specifically including the following steps:

[0007] Step 1: CsPbBr3 quantum dot solution is mixed with PDMS and crosslinked to form a composite film;

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

[0009] Step 3: Place the composite film in anion exchange solution, and use software to control the laser path to perform laser-induced anion exchange to pattern the encrypted information;

[0010] Step 4: Illuminate the patterned encrypted information with an ultraviolet lamp to make it fluoresce, and then filter it with a 470±10nm narrowband filter to obtain the filtered encrypted information pattern.

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

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

[0013] Preferably, in step 1, the curing agent is added to the PDMS and CsPbBr3 quantum dot solution, stirred thoroughly, and then coated onto a glass substrate. After annealing, a composite film is obtained. The mass of the curing agent is 0.1 times the mass of the PDMS, the volume ratio of PDMS to CsPbBr3 quantum dot solution is 1:1, the concentration of 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 is designed that includes obfuscated information and correct information. The specific process is as follows: design a QR code information pattern that stores the correct information, and add an obfuscated information pattern to it to obtain an encrypted information pattern.

[0015] Preferably, in step 2, an encrypted information pattern is designed that includes obfuscated information and correct information. The specific process is as follows: the correct digital information is converted into binary form, and the patterns represented by "1" and "0" are determined, and obfuscated information patterns are added to them to obtain the encrypted information pattern.

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

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

[0018] Preferably, 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.

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

[0020] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0021] (1) This invention utilizes the specific transmission, reflection, or absorption characteristics of filters to selectively allow light within certain wavelength ranges to pass through while blocking other wavelengths, thereby precisely controlling the display of encrypted patterns and improving the accuracy of the encryption process. (2) The anion exchange technology proposed in this invention can achieve precise control of the emission wavelength by adjusting the laser parameters, thus creating unique, precise, and difficult-to-replicate emission patterns.

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

[0023] (4) The QR code used in this invention has a wide range of applications. As encrypted information, it will not attract special attention and has a strong hiding effect.

[0024] (5) The equipment used in this invention is inexpensive and the optical path is simple and easy to understand.

[0025] (6) The invention has strong scalability. 1) By changing the type of haloalkanes, a wider spectral tuning can be achieved, which provides the possibility for full-color encryption applications. 2) The prepared composite film is ultra-flexible and can be bent and folded into different shapes at will. After multiple bending and folding, it can still maintain a high photoluminescence (PL) intensity. Moreover, the stability of the perovskite coated with PDMS is greatly improved, so the technology has strong environmental adaptability. Attached Figure Description

[0026] Figure 1 This is a schematic diagram of the CsPbBr3-PDMS composite film formation.

[0027] Figure 2 The images show the CsPbBr3-PDMS composite film under (a) natural light and (b) ultraviolet light.

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

[0029] Figure 4 This is a schematic diagram of laser-induced anion exchange.

[0030] Figure 5 This refers to a QR code containing obfuscated information, prepared by laser induction under ultraviolet light irradiation.

[0031] Figure 6 This is a diagram illustrating the decryption process.

[0032] Figure 7 To filter out the correct information from the QR code by using a 470±10nm narrowband filter under ultraviolet light.

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

[0034] Figure 9 This refers to a binary encrypted information pattern containing obfuscated information, prepared by laser induction under ultraviolet light irradiation.

[0035] Figure 10 To filter out the correct binary encrypted information pattern by using a 470±10nm narrowband filter under ultraviolet light.

[0036] Figure 11 The patterning of the induced thin film under the same laser parameters is shown in (a) as an actual image under ultraviolet light irradiation and (b) as an image taken under ultraviolet light irradiation using a 470±10nm narrowband filter. Detailed Implementation

[0037] The present invention will be further illustrated below with specific test examples. It should be understood that these embodiments are for illustrative purposes only and are not intended to limit the scope of the invention. After reading the present invention, any modifications of the present invention in various equivalent forms by those skilled in the art will fall within the scope defined by the appended claims.

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

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

[0040] Unless otherwise specified in the examples, the procedures should be performed under standard conditions or conditions recommended by the manufacturer. Reagents or instruments whose manufacturers are not specified are all commercially available products.

[0041] As used herein, the term “about” is used to provide for the flexibility and imprecision associated with a given term, measure, or value. Those skilled in the art can readily determine the degree of flexibility for a particular variable.

[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” explicitly includes only A, only B, only C, and combinations thereof.

[0043] In this embodiment of the invention, a green composite film was first prepared using CsPbBr3 quantum dots and PDMS. Then, a blue encrypted pattern with obfuscated information (due to the presence of chloride ions in the anion exchange solution) was prepared using laser-induced anion exchange. Finally, the information was decrypted using three decryption methods (ultraviolet lamp, 470±10nm narrowband filter, and smartphone). Specifically, the green composite film was immersed in an anion exchange solution whose main component was chloroform, and the solution was irradiated with a 532nm laser to generate Cl... - The green light emitted from the composite film is gradually converted into blue light with a wavelength of 471nm, resulting in a patterned QR code with the correct information. Then, the composite film is irradiated under different laser parameters, causing its green light to gradually convert into blue light with a wavelength of 500nm, resulting in a patterned obfuscated information. Finally, the encrypted pattern is irradiated with an ultraviolet lamp, and the obfuscated information is filtered out using a 470±10nm narrowband filter. A smartphone is then used to photograph and decrypt the image, revealing the correct encrypted information.

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

[0045] Example 1

[0046] Example 1 demonstrates the use of QR codes for encrypted information storage. By storing information within a valid QR code and adding obfuscating information, the encrypted information is hidden. The specific steps are as follows, along with the main experimental setup and operating procedures. Figure 1 , Figure 4 and Figure 6 As shown in the figure. The laser outputs a 532nm pulsed laser, the material composited with the thin film is PDMS, the halide ion solution is chloroform, and the perovskite quantum dots are CsPbBr3.

[0047] Step 1: Mix CsPbBr3 quantum dot solution with PDMS to prepare composite thin film. A schematic diagram of the process is shown below. Figure 1 As shown, the specific steps are as follows:

[0048] Step 1.1: First, sonicate the glass slide in deionized water, isopropanol and acetone for 10 minutes in sequence, then dry it with nitrogen gas and treat it with ultraviolet light for 20 minutes.

[0049] Step 1.2: Add approximately 0.1 times the mass of the curing agent of PDMS to 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 thoroughly until homogeneous, and then remove air bubbles by vacuuming.

[0050] Step 1.3: Place the prepared glass slide on a scraper, drop an appropriate amount of CsPbBr3-PDMS solution onto 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. The final CsPbBr3-PDMS composite film was prepared. A photograph of the film in its normal state is shown below. Figure 2 As shown in (a), it emits a green glow under ultraviolet light, as... Figure 2 As shown in (b) of the diagram.

[0052] Step 2: Use QR codes to store encrypted information. A QR code information pattern was designed to store 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 the figure.

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

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

[0056] Step 3: Place the composite film in anion exchange solution, and use EzCad2 software to control the laser path to perform laser-induced anion exchange and pattern the encrypted information. A schematic diagram of the laser device is shown below. 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 1:1) to a mixture of chloroform (as chlorine source) and toluene in a volume ratio of 1:1 to obtain anion exchange solution. Immerse the CsPbBr3-PDMS composite membrane in the anion exchange solution.

[0058] Step 3.2: Laser-induced anion exchange is achieved by controlling the laser path using EzCad2 software. Figure 3 The patterning of image (a) was performed using the following laser parameters: wavelength 532nm, scanning speed 8mm / s, frequency 50Hz, and laser power 580μJ.

[0059] Step 3.3: Again, control the laser path using EzCad2 software to perform laser-induced anion exchange, achieving... Figure 3 The patterning of the obfuscated information in the red portion of image (b) was performed using the following laser parameters: wavelength 532 nm, scanning speed 8 mm / s, frequency 50 Hz, and laser power 80 μJ. The final physical image is shown below. Figure 5 The image on the left shows obfuscated information in light blue, while the rest represents correct information. This pattern yields no information when scanned with a mobile phone, as shown below. Figure 5 The image on the right.

[0060] Step 4: Decryption is performed using an ultraviolet lamp, a 470±10nm narrowband filter, and a photographic device. A schematic diagram of the decryption process is shown below. Figure 6 As shown.

[0061] Step 4.1: Under ultraviolet light, filter the QR code image using a 470±10nm narrowband filter. Patterns with emission wavelengths outside the 470±10nm range will be filtered out. The final result is a QR code with correct information. The actual effect image 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”, such as... Figure 7 As shown in the image on the right.

[0063] Example 2

[0064] Example 2 demonstrates the encryption of digital information using binary representation. By converting digital information into binary form and adding obfuscation information, encrypted data is constructed, thereby achieving the hiding and protection of the original data. The specific steps are as follows: the laser outputs a 532nm pulsed laser; the material composited with the thin film is PDMS; the halide ion solution is chloroform; and the perovskite quantum dots are CsPbBr3.

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

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

[0067] Step 2.1: Figure 8 (a) presents a binary encrypted information pattern based on "circles" and "squares," containing obfuscated and correct information. The light blue portion represents the obfuscated information, and the dark blue portion represents the correct information. The "circular pattern" represents the digit "1," and the "square pattern" represents the digit "0." The patterns representing "0" and "1" can also be other patterns, not limited to those described above. The first row of patterns, when read, yields the binary information "10," which, when converted to decimal, represents the digit "2." The subsequent rows are read using the same method, ultimately yielding the erroneous information "822198." Figure 8 (b) is the binary encryption pattern after removing the obfuscated information. The first row of patterns is read to get the binary information "1000", which is the number "8" in 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: Following the design encryption approach in Step 2.1, import the designed binary encryption pattern information containing both obfuscated and correct information into the EzCad2 software as the laser's planning path.

[0069] Step 3: Place the composite film in anion exchange solution, and use EzCad2 software to control the laser path to perform laser-induced anion exchange and pattern 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 1:1) to a mixture of chloroform (as chlorine source) and toluene in a volume ratio of 1:1 to obtain anion exchange solution. Immerse the CsPbBr3-PDMS composite membrane in the anion exchange solution.

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

[0072] Step 3.3: Again, control the laser path using EzCad2 software to perform laser-induced anion exchange, achieving... Figure 8 The patterning of the light blue pattern (obfuscating information) in (a) was performed using the following laser parameters: wavelength 532 nm, scanning speed 8 mm / s, frequency 50 Hz, and laser power 80 μJ. The final result is shown in the image below. Figure 9 The image on the left shows information in light blue that is misleading, while the rest is correct.

[0073] Step 4: Decrypt using an ultraviolet lamp, a 470±10nm narrowband filter, and a photographic device.

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

[0075] Step 5: Read the encrypted information pattern obtained in Step 4, such as... Figure 10 According to the rule that a "circular pattern" represents the number "1" and a "square pattern" represents the number "0", converting binary to decimal yields the data "210094", which is the correct encrypted information.

[0076] Comparative Example 1

[0077] The other processes are the same as in Example 1, except that in step 3, when the composite film is patterned, the same laser parameters are used for patterning both obfuscated and correct information, i.e., the following laser parameters are used for scanning: wavelength 532nm, scanning speed 8mm / s, frequency 50Hz, and laser power 580μJ. Figure 11Image (a) shows the actual object under ultraviolet light. Figure 11 (b) is an image taken under ultraviolet light using a 470±10nm narrowband filter, in which the obfuscating information cannot be filtered out.

[0078] The above embodiments are merely preferred embodiments of the present invention, but the implementation of the present invention is not limited to the above embodiments. Any changes, modifications, substitutions, or combinations made without departing from the spirit and principle of the present invention, such as various combinations of solutions in the embodiments, should be considered equivalent replacements and are all within the protection scope of the present invention.

Claims

1. A method for displaying multiple encrypted information using laser-induced anion exchange, characterized in that, Specifically, the steps include the following: Step 1: CsPbBr3 quantum dot solution is mixed with PDMS and crosslinked to form a composite film; Step 2: Design an encrypted information pattern that includes both obfuscated and correct information, and import the pattern information into EzCad2 software as the laser planning path; Step 3: Place the composite film in anion exchange solution, and use software to control the laser path to perform laser-induced anion exchange to pattern the encrypted information; Step 4: Illuminate the patterned encrypted information with an ultraviolet lamp to make it fluoresce, and then filter it with a 470±10nm narrowband filter to obtain the filtered encrypted information pattern. Step 5: Read the encrypted information pattern obtained in Step 4; In step 3, the laser path is controlled by EzCad2 software, and laser-induced anion exchange is performed using different laser parameters to pattern the encrypted information. The correct information is scanned using the following laser parameters: wavelength 532nm, scanning speed 8mm / s, frequency 50Hz, and laser power 580μJ. The obfuscated information is scanned using the following laser parameters: wavelength 532nm, scanning speed 8mm / s, frequency 50Hz, and laser power 80μJ.

2. The method as described in claim 1, characterized in that, Encrypted information includes QR code information and digital information.

3. The method as described in claim 1, characterized in that, In step 1, the curing agent is added to the PDMS and CsPbBr3 quantum dot solution, stirred thoroughly, and then coated onto a glass substrate. After annealing, a composite film is obtained. The mass of the curing agent is 0.1 times the mass of the PDMS, the volume ratio of PDMS to CsPbBr3 quantum dot solution is 1:1, the concentration of 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 as described in claim 1, characterized in that, In step 2, an encrypted information pattern is designed that includes obfuscated information and correct information. The specific process is as follows: design a QR code information pattern that stores the correct information, and add an obfuscated information pattern to it to obtain an encrypted information pattern.

5. The method as described in claim 1, characterized in that, In step 2, an encrypted information pattern is designed that includes obfuscated information and correct information. The specific process is as follows: the correct digital information is converted into binary form, and the patterns represented by "1" and "0" are determined. Obfuscated information patterns are then added to these patterns to obtain the encrypted information pattern.

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

7. The method as described in 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.

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

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