CN100401337C - Quantum point safety device and method - Google Patents
Quantum point safety device and method Download PDFInfo
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- CN100401337C CN100401337C CNB031600816A CN03160081A CN100401337C CN 100401337 C CN100401337 C CN 100401337C CN B031600816 A CNB031600816 A CN B031600816A CN 03160081 A CN03160081 A CN 03160081A CN 100401337 C CN100401337 C CN 100401337C
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- fluorescence
- quantum dot
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- reader
- safety equipment
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Abstract
The present invention relates to a quantum dot which is used as a fluorescent marker in safety ink, paper, plastics, explosives or other articles or substances which need providing a specific signature or a mark. Quantum dots with a specific size, a specific ingredient and a specific structure can be used for generating specific fluorescence; a quantum dot mixture can be used for generating a random pattern of fluorescence with a changeable spectrum; a specific quantum dot structure can be used for providing desired physical and optical characteristics. The quantum dot can be read by an optical reader which can be combined with a reader which uses another technology.
Description
The present patent application is that application number is dividing an application of 00100861.7 application, and the applying date of original application is on February 15th, 2000, and denomination of invention is " Guantum dot safety device and a method ".
Technical field
The present invention relates to quantum dot, relate in particular to quantum dot and be used for safety applications.
Background technology
Quantum dot comprises its optics and physical characteristics and manufacture method, existing description and open in following publication:
1.Warren C.W.Chan, " the quanta point biological complex is used for the inspection of hypersensitive anisotropy " of Shuming Nie, " science " 281 (5385): 2016
2.Marcel Burchez J r.Mario Moronne, Peter Gin, Shimon Weiss, " the semiconductor microcrystallite is as the biological label " of A.PaulAlivisators, " science " 281 (5385): 2013
3.L.E.Brus, " applied physics " A53,465 (1991)
4.W.L.Wilson, P.F.Szajowski, L.E.Brus, " science " 262,1242 (1993) 5.A.Henglein, Chem.Rev.89,1861 (1989)
6.H.Weller，Angew.Chem.Int.Ed.Engl.32，41(1993)
7.M.A.Hines?and?P.Guyot-Sionnest，J.Phys.Chem.100，468(1996)
8.B.0.Dabbousi，et?al.J.Phys.Chem.B101，9463(1997)
9.C.B.Murray，D.J.Norris，M.G.Bawendi，J.Am.Chem.Soc.115，8706(1993)
10.X.G.Peng，J.Wickham，A.P.Alivasatos，J.Am.Chem.Soc.120，5343(1998)
11.L.M.Lizmarzan，M.Giersig，P.Mulvaney，Langmuir?12，4329(1996)
12.M.A.CorreaDuarte，M.Giersig，L.M.LizMarzan，Chem.Phys.Lett.286，497(1998)
13.Marcel Bruchez Jr.Mario Moronne, Peter Gin, Shimon Weiss, and A.Paul alivisatos, " the semiconductor microcrystallite is as the biological label " " science " 1998September 25; 281:2013-2016.
14.Warren C.W.Chan and Shuming Nie, " the quanta point biological complex is used for the hypersensitive anisotropy and detects " " science " 1998September25; 281:2016-2018.
Above-mentioned publication has been described the manufacturing quantum dot, the method for the CdSe crystal that covers as the CdSe-CdS of millimicro meter level and ZnS.This publication has also been described the physics and the optical characteristics of these quantum dots.Especially, in people's such as people's such as Chan article (publication 1) and Burchez Jr. article (publication 2), the quantum dot with following fluorescent characteristic has been described:
High fluorescent can be compared with the rhodamine 6G of ZO molecule;
Emission spectrum is equivalent to 1/3rd of a typical organic dyed labels latex balloon;
Compare with typical organic dyestuff, its photofading rate will be hanged down 100 times;
Long fluorescence lifetime is similar to hundreds of nanoseconds;
Fluorescence spectrum peak value and lateral size of dots have very close mutual relationship.
Summary of the invention
According to an aspect of the present invention, a kind of counterfeit security system that prevents is provided, comprise: have the safety equipment that can detect fluorescent characteristics in first side, described feature is in random site, and described safety equipment also have the readable message that obtains according to the characteristic of described feature and/or position; Be used to read the characteristic of described readable message and described feature and/or the reader of position, described reader comprises that being used for the described message of verification is the device that characteristic and/or position according to the described feature on the described safety equipment draw, described reader also comprises a lighting source, with light from the lead device of described safety equipment of this lighting source, detection is by the device of the safety equipment that light the threw light on institute emitted fluorescence of this lighting source and measure spectrum and/or the time and/or the space characteristics of this fluorescence, thereby determine the characteristic of the described feature on the described safety equipment and/or the device of position.
Quantum dot can be used as the fluorescence labelling thing in needs provide safety ink, paper, plastics, explosive or other any article or the material of unique signature or mark.Because quantum dot has controllable photoluminescence peak color, unique narrow fluorescence spectrum, long significantly fluorescence lifetime, and can make its fluorescent characteristic be independent of the characteristics such as environment that it contacted basically, therefore, quantum dot is better than the fluorophore of standard in above application.The quantum dot of specific size, composition and structure can be used for producing specific fluorescence, and the potpourri of quantum dot can be used for producing the arbitrary graphic pattern with the variable fluorescence of spectrum, and special quantum-dot structure can be used for the physics and the optical characteristics that provide required.
Description of drawings
Fig. 1 is included in the synoptic diagram that comes marked product among a kind of plastics with quantum dot.
Fig. 2 is the quantum dot synoptic diagram of a gland, represent that a quantum dot has a gland layer and another molecule organic layer, the effect of this organic layer is under the condition of the light that has special wavelength, this quantum dot and additional organic molecule are combined, or combine with suitable organic molecule.
Fig. 3 is the planimetric map of safety label, this safety label has a pad of peeling off, a pressure sensitive adhesive coating, a paper substrate layer of printing by the fluorescence quantum ink, and a transparent hologram that has " window ", see through and should " window " character string be printed on this paper substrate layer.
Fig. 4 is the optical module synoptic diagram of holographic reader, and being used to read with hologram and/or phosphor pattern is the safety label of form, and wherein this phosphor pattern has unique emission spectrum or fluorescence lifetime, for example those characteristics of quantum dot.
Fig. 5 is the skeleton view that is used to read the combined reader of hologram on the printing cards and fluorescence quantum.
The chart of Fig. 6 has shown that quantum dot fluorescence is with the difference between the fluorescence of typical organic dyestuff.
Fig. 7 is by safety label reader, character string printer, character string and safety label reader and communication network, is used to prevent and/or detect the process flow diagram of the system of counterfeit product.
Embodiment
According to one embodiment of present invention, the fluorescent characteristic of quantum dot can be used for providing a kind of on certain surface or in material the method for canned data, come thereby effective product or document distinguished with invalid product or document.For example, as shown in Figure 1, quantum dot 200 is comprised in by suitable material, as plastics make the eye 210 in.According to following each embodiment of the present invention that will describe, this eye 210 can as Teddy bear, come authorizing product with the difference of unauthorized product.
According to the application of the quantum dot of each embodiment of the present invention, will in following example, give to describe.As shown in Figure 2, a kind of quantum dot-labeled UV-solidifiable ink that is used for anti-counterfeit/safety applications can use by ZnSe and make around outer CdSe quantum dot 500 as gland 520.This is prepared by existing method by the CdSe quantum dot of ZnSe gland, is had the Size Distribution and the optical characteristics of uniqueness by the light 510 of quantum dot emission.For example, because quantum dot has the relevant rate of deposition of size,, quantum dot is pressed its size separation so can use centrifuge method.Alternatively, can use different conditions to make each batch quantum dot in developmental process, depart from its size, then, each batch quantum dot can be mixed selectively, have the potpourri that special size distributes so that prepare out.
As shown in Figure 3, a collection of ready quantum dot potpourri 410 by stirring reasonable time, as four hours, can be suspended in a kind of transparent UV-solidifiable resin, thereby make a kind of fluorescence UV-solidifiable ink 415.Many UV-solidifiable resins and ink can be buied from manufacturer at US and European.In the ink amount of quantum dot can height can be low.This ink is printed in the pattern on the paper stock that has adhesive coating and peeling paper pad 420, is cured by ultraviolet photoetching then.Then this paper that produces is carried out die-cut, to make the autoadhesion label 435 of rolling.
This label 435 can be read by a reader, as shown in Figure 4.This reader comprises an optical system, and it is by the light of suitable wavelength, and for example the light of 514nm throws light on to selected zone on the label.This light is used to read a zone on the label of being printed by quantum dot-labeled ink 415 690.This reader is collected institute's emitted fluorescence 660 from illuminated label, and analyzes its spectrum and time response.A lens combination 635 is focused into a point with this fluorescence light source, and a diffraction grating 615 is extended to its spectrum with this fluorescence light source on the linear array 625 of a photoelectric detector.Electronic circuit passes through the modulation illumination light, and will modulation and institute's emitting fluorescence of this illumination light be compared because of the variation that modulation takes place, thereby the time behavior of this fluorescence is analyzed.
Reader shown in Figure 4 can make up with the reader of other technology of use, for example magnetic strip reader as shown in Figure 5.
By using a kind of short pulse of exciting light to certain sample, and observation post's emitted fluorescence intensity in during hundreds of nanoseconds, the fluorescence of elapsed time parsing can be measured.In this article, " weak point " is to compare with this fluorescence lifetime.Most of fluorescent materials are only launched several nanoseconds light after activating, but the CdSe500 quantum dot of ZnS gland 520 can be launched hundreds of nanoseconds light usually after activating, shown in the right side of Fig. 6.The left side of Fig. 6 demonstrates the difference between quantum dot fluorescence and the typical organic dyestuff fluorescence.Another method of measuring the fluorescence that the elapsed time resolves is at this exciting light of one or more frequencies (as kHz-mHz) modulation, and observes this and activate phase relation between first modulation and the institute's emitted fluorescence light source modulation.More than two kinds of methods can clearly quantum dot fluorescence and organic dyestuff fluorescence be made a distinction.
By observing the three-dimensional spread spectrum of fluorescence, can make a distinction according to the bandwidth of quantum dot fluorescence fluorophore with this quantum dot and other kind.Spectrum and the combinatory analysis of time to fluorescence can be significantly with amounts
The fluorophore that son point and other any counterfeiter may be used for reaching identical fluorescent characteristic is distinguished and is come.The combination of spectrum and time fluorescent characteristic can be referred to as the fluorescence signature.
Reader shown in Figure 4 when label moves through this reader, reads on this label the fluorescence of each spot signature in a series of flecks.If this quantum dot presents very high concentration, thereby make each spot all comprise the typical sample of a quantum dot potpourri, each spot will produce identical fluorescence signature, and it can only duplicate by the method for duplicating the quantum dot potpourri.Therefore, this fluorescence signature provides the evidence in label source.
Thereby far on average have only one or several quantum dot to exist in each spot if these quantum dots are separated from one another, then each spot will have the fluorescence signature of oneself.This series fluorescence signature can be from a series of spot measurements of whole label, and then determine by the random site of various quantum dots on the label, and all are unique for each label.These a series of fluorescence signatures can be referred to as " phosphor pattern ".
Because the phosphor pattern on each label is unique, thus can be at the phosphor pattern of making on link or the applied links reading tag, and be input in the middle of the database.In sales section or distribution link, these phosphor patterns can be read, and are complementary with pattern in the database then.If certain pattern is detected not in the middle of database, then it is exactly certain counterfeiter evidence of the manufacture method of counterfeit quantum dot-labeled label.
Do not use database because it may require huge communication network, label can add the character string that comprises a kind of printing.This character string contains the enciphered message of representing this phosphor pattern.For example use phosphor pattern can generate this character string as key in a public-key cryptography scheme, this enciphered message can identification (RFID) tag printing person and this information is encrypted and this character string is printed on date on the label.Therefore at the sales section of the product of doing tag processes, reader both can read this phosphor pattern and also can read this character string, deciphered this character string, and extracted enciphered message, thus the validity of verification label and product.
The system that utilizes a kind of safety label reader to be used to prevent and/or detect counterfeit product as shown in Figure 7.This system comprises and uses a character string printer (not shown), character string and safety label reader (not shown), and a communication network (not shown).
The potpourri of quantum dot can be as the marker in the explosive.According to this embodiment of the invention, having a predetermined cun quantum dot that distributes to the greatest extent can join in explosive or other material in the fabrication phase, thereby according to time and/or these materials of place marks of making.
According to another embodiment of the invention, quantum dot can be arranged on a surface upward so that information stores to be provided.Especially can prepare quantum dot in batch, each batch all has unique spot size among a small circle.Each mark words and phrases for special attention all scribble can be photosensitive bonding agent, dichromic acid gel for example.A kind of optical system is focused into very speckle with laser beam scribbling on the surface of first quantum dot, it is similar to micron on diameter, the whole surface of this laser beam flying, open and close according to the position, thereby in this laser beam is when being in open mode, marking words and phrases for special attention first is glued together, and rinsing is carried out to remove not bonding quantum dot in this surface.Coat second for then this surface and mark words and phrases for special attention, repeat this process by different irradiation patterns.Respectively marking words and phrases for special attention subsequently provides the further bonding of different quantum dot sizes with irradiation pattern, and each batch all has own unique pattern.
Because the size of a general quantum dot is less than 4 millimicrons, a surface can hold 6,250,000 quantum dot/square micron or 6,250,000,000,000 point/square centimeter.Can or more prepare quantum dot on the specific dimensions 20 by accurate control growth time and condition or by physical separation method, be similar to 50 with current, 000,000/square centimeter high density magnetic storage density is compared to produce and is similar to 100,000,000,000,000/square centimeter total storage capacity.
The near-field scan optic probe that utilizes a probe size to compare with a quantum dot size can read the information that is stored on the label.
In order to produce the duplicate of quantum dot pattern by batch, can prepare a master pattern by using the method that generates original quantum dot pattern with quantum dot to the unique dna sequence dna mark of the size of this quantum dot.After being ready to complete, master pattern prepares a duplicate then by following steps:
1. master pattern is full of with the quantum dot that scribbles mercaptan demarcation DNA, this mercaptan demarcation adds DNA and is complementary to the DNA on the respective point on this master pattern, and allows complementary DNA chain synthetic.
2. rinse unnecessary quantum dot from master pattern.
3. prepare a flat glass sheet, at its surperficial vapour deposition one gold plating, this glass sheet is immersed in the ethanolic solution of 11-sulfhydryl undecanoic acid (MUA) of a millimole amount and soaked 18 hours, so that individual layer MUA and gold plating are combined, then, exist under the condition of NaHC03, how basic L-lysine is being adsorbed onto this individual layer MUA, then, add thiosuccimide-4-(N-maleimide methyl) cyclohexane-1-shuttle thing (SSMCC) to this individual layer MUA.This SSMCC and remaining lysine react the surface that comprises the maleimide group that can react with generation.
4. the gold surface of treated this glass sheet is pressed to this master pattern, thereby make a part of mercaptan on each quantum dot delimit DNA and this can react the maleimide set of contact.Allow this master pattern and glass sheet be pressed together and kept 12 hours, this mercaptan demarcation DNA and this maleimide group are reacted, and combine.
5. to the assembling device heating, complementary DNA chain is separated, and this glass sheet and this master pattern are broken away from.Then this glass sheet will have the quantum dot pattern, and it is the mirror image of this master pattern.
This duplicate comprises identical (or corresponding) quantum dot in the pattern identical with master pattern.By same steps as, a plurality of duplicate can be from a master pattern, made, and reproduction making duplicate can be passed through, thus can be from a large amount of duplicate of single master pattern production.
RNA has the similar particular combination characteristic with DNA, makes up as antibody/antigen; These or other any particular combination method all can essentially identical mode be used.
Fluorescent ink as described herein can be applied to the printing process of any standard, as long as it is fit to make quantum dot to be suspended in wherein carrier.A kind of preferred printing process is exactly an inkjet printing, because it can print variable information with the form of dissimilar quantum dots in different printing points.
Method as described herein can make amendment and adjust in every way.For example:
The composition of quantum dot and structure, as the selection of material, and the having or not of different material layers, all can change to produce different absorbabilities and fluorescence property;
This photosensitive adhesive can be selected from any known a lot of photosensitive adhesives;
The density of quantum dot can change in any scope that detects density on the label or in the material; Exciting light can change between long wavelength that can activate employed specific quantum dot and minimal wave length;
The pattern of quantum dot can be that be scheduled to, periodic, quasi periodic or at random on the label; Any device that can detect the time resolution fluorescence of fluorescence spectrum and/or quantum dot all can use;
Any fluorescent ink, particle, fiber or other structure or material all can use among the opaque reflection hologram or among the transmission hologram or under;
Quantum dot can have the detectable feature of optics, electromagnetism, chemistry, acoustics or mechanical means with any other and combine, so that the anti-counterfeit security mechanism that can further strengthen to be provided;
Any material or structure with adhesion characteristic all can be used in the reproduction process of quantum dot pattern;
Can use that a near field optic scanning probe microscopy, conventional microscope, fluorescent microscope, epifluorescence microscope, spectrofluorimeter or other are any can to read quantum dot pattern or distribution with being in separately or the distribution of the quantum dot under the collocation state or the device that arrangement, position or characteristic make a distinction;
Time resolution fluorescence can use the activation of simple pulse, square-wave pulse, Sine Modulated light or Adaptive Modulation light to detect;
Activation can be realized by any epipolic light and light source of can activating in the quantum dot of LASER Light Source, incandescent lamp, metal vapor discharge light or other;
The photoconductivity of semiconductor-quantum-point or absorption spectrum can be used to detect the existence and the characteristic of quantum dot;
In the present invention, label does not need hologram; They can utilize the combination of quantum dot ink, quantum dot ink and other ink to print simply, can be printed on the paper or other contains quantum dot or carry out on the substrate of coating or covering with the layer that contains quantum dot.
Even should be appreciated that to have provided various embodiment of the present invention and advantage in above description, but above-mentioned disclosing only is illustrative, still can make change in detail, as long as still be retained within the broad principles of the present invention.Therefore, the present invention is only limited by claims.
Claims (5)
1. one kind prevents counterfeit security system, comprising:
Have the safety equipment that can detect fluorescent characteristics in first side, described feature is in random site, and described safety equipment also have the readable message that obtains according to the characteristic of described feature and/or position; With
Be used to read the characteristic of described readable message and described feature and/or the reader of position, described reader comprises that being used for the described message of verification is the device that characteristic and/or position according to the described feature on the described safety equipment draw,
Described reader also comprises a lighting source, with light from the lead device of described safety equipment of this lighting source, detection is by the device of the safety equipment that light the threw light on institute emitted fluorescence of this lighting source and measure the spectrum of this fluorescence and/or thereby time and/or space characteristics are determined the characteristic of the described feature on the described safety equipment and/or the device of position.
2. according to the security system of claim 1, the device of wherein measuring the spectrum of this fluorescence and temporal characteristics comprises and being used for quantum dot fluorescence and organic dyestuff fluorescence, the device that makes a distinction by transmitted bandwidth or fluorescence lifetime.
3. according to the security system of claim 2, wherein this discriminating device comprises and is used for the light of modulation from this lighting source, and the device of the phase differential as a result between the modulation of the modulation of this lighting source light and fluorescence relatively.
4. according to the security system of claim 2, wherein this discriminating device comprises the device that is used to analyze this fluorescence spectrum.
5. according to the security system of claim 2, wherein this discriminating device comprises and is used for measuring the device of this fluorescence intensity in one group of predetermined wavelength and/or time.
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNB001008617A CN1141680C (en) | 2000-02-15 | 2000-02-15 | Guantum dot safety device and method |
Related Parent Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CNB001008617A Division CN1141680C (en) | 2000-02-15 | 2000-02-15 | Guantum dot safety device and method |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN1495681A CN1495681A (en) | 2004-05-12 |
| CN100401337C true CN100401337C (en) | 2008-07-09 |
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Family Applications (2)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CNB001008617A Expired - Lifetime CN1141680C (en) | 2000-02-15 | 2000-02-15 | Guantum dot safety device and method |
| CNB031600816A Expired - Lifetime CN100401337C (en) | 2000-02-15 | 2000-02-15 | Quantum point safety device and method |
Family Applications Before (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CNB001008617A Expired - Lifetime CN1141680C (en) | 2000-02-15 | 2000-02-15 | Guantum dot safety device and method |
Country Status (1)
| Country | Link |
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| CN (2) | CN1141680C (en) |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102912675B (en) * | 2012-10-15 | 2015-08-12 | 保定钞票纸业有限公司 | A kind of quantum dot fluorescence cheque paper and manufacture method thereof |
| WO2015036045A1 (en) * | 2013-09-13 | 2015-03-19 | CSEM Centre Suisse d'Electronique et de Microtechnique SA - Recherche et Développement | Lightguide tamper seal |
| CN106009931B (en) * | 2016-05-05 | 2018-12-07 | 中国科学院长春光学精密机械与物理研究所 | Information ciphering method and encryption system and encryption information read method and reading system |
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| CN1090074A (en) * | 1993-01-20 | 1994-07-27 | 陈刚 | The method of making composite holographic label on commodity package |
| CN1027204C (en) * | 1992-09-19 | 1994-12-28 | 南京大学 | Method for preparing visible photoluminescent silicon quantum point |
| CN1131176A (en) * | 1995-01-03 | 1996-09-18 | 通用电气公司 | Quantum splitting oxide phosphors and method of making same |
| CN1032940C (en) * | 1992-08-17 | 1996-10-02 | 汤姆森电子消费品公司 | Unforgeable identification device, identification device reader and method of identification |
| CN2266770Y (en) * | 1995-12-21 | 1997-11-05 | 沈良骏 | Random cipher code antifake mark label |
| CN1165176A (en) * | 1996-03-29 | 1997-11-19 | 通用电气公司 | Process for producing quantum splitting phosphors and novel compositions |
| WO1998022914A2 (en) * | 1996-11-20 | 1998-05-28 | Tecsec, Incorporated | Cryptographic medium |
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2000
- 2000-02-15 CN CNB001008617A patent/CN1141680C/en not_active Expired - Lifetime
- 2000-02-15 CN CNB031600816A patent/CN100401337C/en not_active Expired - Lifetime
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1032940C (en) * | 1992-08-17 | 1996-10-02 | 汤姆森电子消费品公司 | Unforgeable identification device, identification device reader and method of identification |
| CN1027204C (en) * | 1992-09-19 | 1994-12-28 | 南京大学 | Method for preparing visible photoluminescent silicon quantum point |
| CN1090074A (en) * | 1993-01-20 | 1994-07-27 | 陈刚 | The method of making composite holographic label on commodity package |
| CN1131176A (en) * | 1995-01-03 | 1996-09-18 | 通用电气公司 | Quantum splitting oxide phosphors and method of making same |
| CN2266770Y (en) * | 1995-12-21 | 1997-11-05 | 沈良骏 | Random cipher code antifake mark label |
| CN1165176A (en) * | 1996-03-29 | 1997-11-19 | 通用电气公司 | Process for producing quantum splitting phosphors and novel compositions |
| WO1998022914A2 (en) * | 1996-11-20 | 1998-05-28 | Tecsec, Incorporated | Cryptographic medium |
Also Published As
| Publication number | Publication date |
|---|---|
| CN1309383A (en) | 2001-08-22 |
| CN1495681A (en) | 2004-05-12 |
| CN1141680C (en) | 2004-03-10 |
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