WO2011104858A1

WO2011104858A1 - Method of identifying fluorescence spectrum

Info

Publication number: WO2011104858A1
Application number: PCT/JP2010/053071
Authority: WO
Inventors: 重雄前田; 潤徳田; 俊弘藤田
Original assignee: Idec株式会社
Priority date: 2010-02-26
Filing date: 2010-02-26
Publication date: 2011-09-01
Also published as: JP4965706B2; JPWO2011104858A1

Abstract

Disclosed is a method of identifying a fluorescence spectrum, which simply and highly accurately discerns multiple types of fluorescence spectrums from each other and discerns fluorescence spectrums disguised as those spectrums. The method identifies multiple types of combined fluorescence spectrums which are comprised of combined waveforms of a first fluorescence spectrum based on a first fluorescent material and a second fluorescence spectrum based on a second fluorescent material and which differ corresponding to the difference in the composition of these fluorescent materials. The method weights a measured fluorescence spectrum (Fm (λ)), which is comprised of a first fluorescence spectrum and a second fluorescence spectrum which overlap and which is measured from an object to be identified, by a first identification function (hα(λ)), a second identification function (hβ (λ)), and a third identification function (hγ (λ)), divides the respectively obtained first weighted average value, second weighted average value, and third weighted average value by the sum of the values to calculate a first identifying value, second identifying value, and third identifying value, and discerns multiple types of combined fluorescence spectrums from each other and determines the authenticity thereof on the basis of the combination of the identifying values.

Description

Fluorescence spectrum identification method

The present invention relates to a method for discriminating a fluorescence spectrum, and more particularly to a method for discriminating a plurality of types of true fluorescence spectra from each other and a false fluorescence spectrum camouflaged by any of them.

Conventionally, predetermined identification information is written on an article by containing a plurality of types of fluorescent materials having different main wavelengths in a predetermined composition, and a fluorescence spectrum corresponding to the identification information is read based on irradiation of excitation light, and the article There are known methods for determining the type of item and determining the authenticity of an article (for example, see Patent Document 1 below). FIG. 13 is a spectrum that qualitatively represents an example of a combination of fluorescence spectra constituting a plurality of types of identification information in the prior art. A combination of the blending amounts of the fluorescent material X having the dominant wavelength λx and the fluorescent material Y having the dominant wavelength λy is used as identification information, and these blending amounts are fluorescence based on the fluorescent material X as shown in FIG. The emission intensity at the principal wavelength λx of the spectrum (x ₁ · fx (λ), x ₂ · fx (λ), x ₃ · fx ₃ (λ) indicated by broken lines) is any one of S1, S2 and S3, In addition, the emission intensity at the main wavelength λy of the fluorescence spectrum based on the fluorescent material Y (y ₁ · fy (λ), y ₂ · fy (λ), y ₃ · fy (λ) indicated by broken lines) is S1 and S2. And S3. That is, one piece of identification information selected from the identification information of nine types (= three types of blending amount (intensity) of fluorescent material X × three types of blending amount (intensity) of fluorescent material Y) is written. In reading, the combined fluorescence spectrum obtained by synthesizing the fluorescence spectrum based on the fluorescent material X and the fluorescence spectrum based on the fluorescent material Y, for example, the intensities at the main wavelengths of the fluorescent material X and the fluorescent material Y are S2 and S3, respectively. When the fluorescent material X and the fluorescent material Y are blended with each other, as shown by the solid line, a synthesis in which the fluorescence spectrum x ₂ · fx (λ) and the fluorescence spectrum y ₃ · fy (λ) are synthesized The fluorescence spectrum F _2,3 (λ) is measured, and a set corresponding to the intensity of the synthesized fluorescence spectrum F _2,3 (λ) at the respective main wavelengths (wavelength λx, wavelength λy) of the fluorescent material X and the fluorescent material Y The identification value is derived.

Each identification value of the set of identification values is within an allowable range of any of the first allowable range (S1 ± δ), the second allowable range (S2 ± δ), and the third allowable range (S3 ± δ). In this case, it is determined that the spectrum is a true spectrum, and identification information is read according to which combination of identification values corresponds to which combination of allowable ranges. The first range (S1 ± δ), the second range (S2 ± δ), and the third range (S3 ± δ) are ranges that do not overlap each other.

In this way, when the identification information and the authenticity are determined by numerical determination based on a set of identification values, the determination can be easily performed by a simple reading device. This is because it is not necessary to display the synthetic fluorescence spectrum in the readout device, and it is possible to make a high-precision and quick determination because no artificial determination is involved.

However, when a set of identification information is determined according to the intensities at the main wavelengths of the fluorescent material X and the fluorescent material Y as in the prior art, a fake fluorescence spectrum from which a similar set of identification values is derived is easy. Can be reproduced. In general, when disguising a fluorescent spectrum as identification information, a fluorescent material that can be easily obtained at low cost is used, and as few fluorescent materials as possible are used.

Here, a conventional technique of camouflage will be briefly described. FIG. 14 is a spectrum showing an example of disguise for a plurality of types of synthetic fluorescence spectra in the past. As shown in FIG. 14, an existing fluorescent material X ′ having a predetermined main wavelength λx ′ (≠ λx, λy) and an existing fluorescent material Y ′ having a predetermined main wavelength λy ′ (≠ λx, λy) are And adjusting the blending amount of the fluorescent material X ′ so that the intensity at the wavelength λx is the same as that in the case of the synthetic fluorescence spectrum F (λ) (= F _2,3 (λ)), and the intensity at the wavelength λy is synthesized. A method of forming a fluorescence spectrum Fs (λ) by adjusting the blending amount of the fluorescent material Y ′ so as to be the same as that of the fluorescence spectrum F (λ) is known. This corresponds to a case where the fluorescent material X ′ or the fluorescent material Y ′ is easily obtained at low cost and is camouflaged by a fluorescent material such as a semiconductor bulk particle or an organic phosphor whose main wavelength is substantially fixed. . For such rough camouflage, fluorescent materials such as semiconductor nanoparticles whose main wavelength varies depending on the particle size and composition are used so that the main wavelengths of fluorescent material X and fluorescent material Y are the same. By selecting the type of fluorescent material, forgery with higher accuracy has been performed. Specifically, as shown in FIG. 14, the fluorescent material X ′ is selected so as to be substantially the same as the main wavelength λx of the fluorescent material X, and the intensity at the wavelength λx has a combined fluorescence spectrum F (λ). The blending amount of the fluorescent material X ′ is adjusted so as to be the same as in the above case, and the fluorescent material Y ′ is selected so as to be substantially the same as the main wavelength λy of the fluorescent material Y, and the intensity at the wavelength λy is increased. A method of adjusting the blending amount of the fluorescent material Y ′ so as to be the same as the case of the synthetic fluorescence spectrum F (λ) to form the fluorescence spectra Fn (λ) and Fw (λ) has come to be used. . As a result, when they are disguised with the fluorescence spectrum Fn (λ) or the fluorescence spectrum Fw (λ), their waveforms are similar to those of F (λ). The importance of discriminating the true / false of will increase.

FIG. 14 shows a synthetic fluorescence spectrum Fn (λ) in which the half widths of the fluorescence spectra based on the fluorescent material X ′ and the fluorescent material Y ′ are narrower than the half widths of the fluorescence spectra based on the fluorescent material X and the fluorescent material Y, respectively. ) And a synthetic fluorescence spectrum Fw (λ) wider than their half-value widths. However, due to the difference in the material system of the fluorescent material, there are various manufacturing processes even in the same material system. This is because the half-value widths of the fluorescence spectra based on these fluorescent materials differ depending on the processing conditions of the above. In the forgery of the synthetic fluorescence spectrum F (λ), since the dominant wavelength is usually adjusted by a change in particle diameter with respect to a phosphor of one type of material, fluorescence having a narrower half width of the fluorescence spectrum than that of the fluorescent material X is used. When the material X ′ is selected, the fluorescent material Y ′ having a narrower half width of the fluorescence spectrum than that of the fluorescent material Y is selected, and conversely, the fluorescent material X ″ having a wider half width of the fluorescence spectrum than that of the fluorescent material X. Is selected, the fluorescent material Y ″ having a half-width of the fluorescence spectrum wider than that of the fluorescent material Y is selected.

Tokurei WO04 / 025550

As described above, depending on the determination based on a set of identification information corresponding to the intensities at the main wavelengths of the fluorescent material X and the fluorescent material Y, various kinds of camouflaged false fluorescent spectra shown in FIG. Whether the fluorescence spectrum is true or false cannot be determined. In general, the intensities at the main wavelengths of the fluorescent material X and the fluorescent material Y change due to a measurement error or the like, so that the accuracy of discriminating each other's fluorescence spectra with respect to a plurality of types of true fluorescence spectra also decreases.

Therefore, in the present invention, the mutual fluorescence spectra for a plurality of types of fluorescence spectra are discriminated easily and with high accuracy, and the fake fluorescence spectra camouflaged as the true fluorescence spectra corresponding to them are discriminated.

In order to solve the above problems, a method for identifying a fluorescence spectrum according to the present invention includes:
A plurality of types of synthesis in which the combined waveform of the first fluorescent spectrum based on the first fluorescent material and the second fluorescent spectrum based on the second fluorescent material is different depending on the blending difference between the first fluorescent material and the second fluorescent material. Fluorescence spectra are discriminated from each other, and the intensity of the first fluorescence spectrum at the dominant wavelength and the second fluorescence spectrum are different from one of the plurality of types of synthetic fluorescence spectra, although the overall waveform is different A fluorescence spectrum identification method for distinguishing between a false fluorescence spectrum having substantially the same intensity at the dominant wavelength and each of the plurality of types of synthetic fluorescence spectra,
Each of the first fluorescent material and the second fluorescent material is a group of semiconductor nanoparticles,
A part of the first fluorescence spectrum and a part of the second fluorescence spectrum constituting each of the plurality of types of synthetic fluorescence spectra overlap,
A single-head peak shape having a distribution function of a single-head peak shape having a mode value in the vicinity of the main wavelength of the first fluorescence spectrum as a first discriminant function and a mode having a mode value in the vicinity of the main wavelength of the second fluorescence spectrum. Is a second discriminant function, and a single-peak distribution function having a mode between the mode value of the first discriminant function and the mode value of the second discriminant function is a third discriminant function. As a discrimination function, a first weighted average value obtained by weighting the measured fluorescence spectrum measured from the identification target with the first discrimination function is calculated, and the second discrimination function is used for the measured fluorescence spectrum. Calculating a weighted second weighted average value, and calculating a third weighted average value weighted by the third discriminant function for the measured fluorescence spectrum;
The first weighted average value is normalized by the sum of the first weighted average value, the second weighted average value, and the third weighted average value to calculate a first identification value for the measured fluorescence spectrum, and the second weighted value Normalizing the average value with the sum to calculate a second identification value for the measured fluorescence spectrum, and normalizing the third weighted average value with the sum to calculate a third identification value for the measured fluorescence spectrum;
The combination of the first identification value, the second identification value, and the third identification value is an allowable range for the predetermined first identification value associated with each of the plurality of types of synthetic fluorescence spectra and a predetermined first value. When the measurement fluorescence spectrum is included in any one combination of the tolerance range for the two identification values and the tolerance range for the predetermined third identification value, the measured fluorescence spectrum is one of the plurality of types of synthetic fluorescence spectra. Is determined to be the same as the synthetic fluorescence spectrum corresponding to the combination, and if it is not included in any combination of the allowable ranges associated with each of the plurality of types of synthetic fluorescence spectra, The measured fluorescence spectrum is determined to be the false fluorescence spectrum.

According to the method for identifying a fluorescence spectrum according to the present invention, based on the combination of the first identification value, the second identification value, and the third identification value, the discrimination of the mutual fluorescence spectra for a plurality of types of fluorescence spectra and corresponding to them. It is possible to easily and accurately discriminate a false fluorescence spectrum that is camouflaged as a true fluorescence spectrum.

A spectrum that qualitatively represents an example of the first fluorescence spectrum and the second fluorescence spectrum A spectrum that qualitatively represents an example of a combination of multiple types of fluorescence spectra Spectrum that shows an example of a combination of multiple types of fluorescence spectra A flowchart for explaining an example of a method for calculating a set of identification values used for information determination and authenticity determination Graph representing an example of an identification function Spectrum showing the relative intensity deviation of the fluorescence spectrum due to measurement error A graph representing the sum of the difference values of various identification values and the absolute values of the difference values for multiple types of fluorescence spectra The graph showing the change of the sum total of the difference value of various identification values with respect to the change of the half value width of the 1st fluorescence spectrum and the 2nd fluorescence spectrum by a measurement error, and the absolute value of those difference values The graph showing the change of the difference value of various identification values with respect to the change of the primary wavelength of the 1st fluorescence spectrum by the measurement error, and the 2nd fluorescence spectrum, and the sum total of the absolute value of those difference values Explanatory drawing showing the difference between an example of a true fluorescence spectrum and an example of a false fluorescence spectrum by narrow-fake camouflage Explanatory drawing showing the difference between an example of a true fluorescence spectrum and an example of a false fluorescence spectrum by wide disguise Explanatory drawing showing the difference between an example of a true fluorescence spectrum and an example of a false fluorescence spectrum due to composite disguise of position and intensity A spectrum that qualitatively represents an example of a combination of synthetic fluorescence spectra that make up multiple types of identification information in the past A spectrum that represents a disguised example of multiple types of synthetic fluorescence spectra in the past

The fluorescence spectrum identification method according to the present invention will be described. In addition, after demonstrating the conceptual structure of the identification method of a fluorescence spectrum, the specific structure is demonstrated, referring drawings.

[Conceptual composition]
In the fluorescent spectrum identifying method according to the present invention, a combined waveform of a first fluorescent spectrum based on a first fluorescent material and a second fluorescent spectrum based on a second fluorescent material is obtained by combining the first fluorescent material and the second fluorescent material. Different types of synthetic fluorescence spectra different from each other according to the difference in the composition are distinguished from each other, and the overall waveform is different from any one of the plurality of types of synthetic fluorescence spectra with respect to any one true fluorescence spectrum, but the first fluorescence spectrum A fluorescence spectrum identification method for discriminating between a false fluorescence spectrum and an intensity of the second fluorescence spectrum that are substantially the same with respect to the dominant wavelength of each of the plurality of types of synthetic fluorescence spectra,
Each of the first fluorescent material and the second fluorescent material is a group of semiconductor nanoparticles,
A part of the first fluorescence spectrum and a part of the second fluorescence spectrum constituting each of the plurality of types of synthetic fluorescence spectra overlap,
Distribution of a single-head peak shape having a mode near the dominant wavelength of the first fluorescence spectrum as a first discriminant function and a distribution function of a single-head peak shape having a mode near the dominant wavelength of the second fluorescence spectrum The function is the second discriminant function, and the single-peak distribution function having the mode between the mode value of the first discriminant function and the mode value of the second discriminant function is the third discriminant function. A first weighted average value of the measured fluorescence spectrum obtained by weighting the measured fluorescence spectrum measured from the identification target with the first identification function is calculated, and the second identification function is calculated with respect to the measured fluorescence spectrum. And calculating a second weighted average value of the measured fluorescence spectrum weighted with the third discriminating function, and calculating a third weighted average value of the measured fluorescence spectrum weighted with the third discrimination function with respect to the measured fluorescence spectrum And
The first weighted average value is normalized by the sum of the first weighted average value, the second weighted average value, and the third weighted average value to calculate a first identification value for the measured fluorescence spectrum, and the second weighted value Normalizing the average value with the sum to calculate a second identification value for the measured fluorescence spectrum, and normalizing the third weighted average value with the sum to calculate a third identification value for the measured fluorescence spectrum;
The combination of the first identification value, the second identification value, and the third identification value is an allowable range for the predetermined first identification value associated with each of the plurality of types of synthetic fluorescence spectra and a predetermined first value. When the measurement fluorescence spectrum is included in any one of the combinations of the tolerance range for the two identification values and the tolerance range for the predetermined third identification value, the measured fluorescence spectrum is one of the plurality of types of synthetic fluorescence spectra. Is determined to be the same as the synthetic fluorescence spectrum corresponding to the combination, and if it is not included in any combination of the allowable ranges associated with each of the plurality of types of synthetic fluorescence spectra, The measured fluorescence spectrum is determined to be the false fluorescence spectrum.
Hereinafter, the identification method of this configuration is also referred to as “identification method A”.

Here, “main wavelength” means a wavelength having the maximum intensity in the fluorescence spectrum based on the fluorescent material. “A part of the first fluorescence spectrum and a part of the second fluorescence spectrum overlap” means that the second fluorescence spectrum is larger than the main wavelength of the first fluorescence spectrum within 1/10 width (FWTM) of the first fluorescence spectrum. The sum of the partial width on the principal wavelength side of the first fluorescence spectrum and the partial width on the dominant wavelength side of the first fluorescence spectrum with respect to the 1/10 width (FWTM) of the second fluorescence spectrum is the first fluorescence. It means that it is larger than the interval between the dominant wavelength of the spectrum and the dominant wavelength of the second fluorescence spectrum.
“Semiconductor nanoparticle” means a particle having a particle size of 100 nm or less.
“Near the main wavelength of the first fluorescence spectrum” means a wavelength between the shortest wavelength and the longest wavelength corresponding to the 9/10 width of the first fluorescence spectrum. "Means a wavelength between the shortest wavelength and the longest wavelength corresponding to the 9/10 width of the second fluorescence spectrum. “Distribution function of a single peak shape” is a function of a shape including a convex peak portion on one point, and according to the change in wavelength from the mode value (maximum value) of the peak portion. It is a function that decreases monotonically and asymptotically converges to “0”.

In the case of the above-described fluorescence spectrum identification method A, the first identification value and the second identification value are the emission intensity of the true first fluorescence spectrum (the blending amount of the first fluorescence material) and the true second fluorescence spectrum, respectively. The emission intensity (the amount of the second fluorescent material) can be estimated well, and the first identification value, the second identification value, and the third identification value are normalized so that the first fluorescence spectrum and the second fluorescence value are normalized. Regardless of the overall emission intensity of the spectrum, the first identification value, the second identification value, and the third identification value are respectively the first fluorescence of the true first fluorescence spectrum and the false fluorescence spectrum that is camouflaged thereto. The difference in the vicinity of the dominant wavelength of the spectrum, the difference in the vicinity of the dominant wavelength of the second fluorescence spectrum between the true second fluorescence spectrum and the false fluorescence spectrum camouflaged to it, and the true first fluorescence spectrum and its false firefly Both the difference between the spectrum and the wavelength of the first fluorescence spectrum different from the main wavelength and the difference between the true second fluorescence spectrum and its fake fluorescence spectrum around the second wavelength of the second fluorescence spectrum and the different wavelength In order to change according to the difference, the ratio of the emission intensity based on the first fluorescent material and the emission intensity based on the second fluorescent material is based on the combination of the first identification value, the second identification value, and the third identification value. Different types of true synthetic fluorescence spectra can be distinguished from each other with high accuracy, and various types of true synthetic fluorescence spectra and various types of false synthetic fluorescence spectra can be distinguished with high accuracy and simplicity.

In the above-described fluorescence spectrum identification method A,
It is preferable that each of the plurality of types of synthetic fluorescence spectra has a double peak shape.
Hereinafter, the identification method of this configuration is also referred to as “identification method B”.

Here, “double-headed peak shape” means a shape including convex peak portions at two locations in the synthetic fluorescence spectrum. In the case where the combined fluorescence spectrum has a double-peak shape, the second half width (FWHM) of the first fluorescence spectrum and the second width of the second fluorescence spectrum on the side of the main wavelength of the second fluorescence spectrum with respect to the second wavelength. The sum of the full width at half maximum (FWHM) of the fluorescence spectrum and the partial width of the first fluorescence spectrum relative to the dominant wavelength of the second fluorescence spectrum is the dominant wavelength of the first fluorescence spectrum and the dominant wavelength of the second fluorescence spectrum. It becomes smaller than the interval.

In the above identification method B, since the main wavelength of the first fluorescence spectrum and the main wavelength of the second fluorescence spectrum are separated by a predetermined distance or more so that various synthetic fluorescence spectra have a double-headed peak shape, The contribution from the true second fluorescence spectrum in one discriminating value is satisfactorily reduced so that the emission intensity of the true first fluorescence spectrum can be estimated with higher accuracy and the true first fluorescence spectrum in the second discriminating value. From which the emission intensity of the second fluorescence spectrum can be estimated more satisfactorily, and the first identification value, the second identification value, and the third identification value are the true fluorescence spectrum and the Various differences from the false fluorescence spectrum are reflected with higher accuracy. Thereby, based on the combination of the first identification value, the second identification value, and the third identification value, a plurality of types of true synthetic fluorescence spectra can be discriminated with higher accuracy, and various types of true synthetic fluorescence spectra and various types of A false synthetic fluorescence spectrum can be distinguished with higher accuracy.

In the above-described fluorescence spectrum identification methods A to B,
It is preferable that the mode value of the third discriminant function has a configuration in a wavelength region where the first fluorescence spectrum and the second fluorescence spectrum overlap.
Hereinafter, the identification method of this configuration is also referred to as “identification method C”.

In the above identification method C, a portion where the difference between the first fluorescence spectrum and the false fluorescence spectrum camouflaged by the first fluorescence spectrum is large, and a portion where the difference between the second fluorescence spectrum and the false fluorescence spectrum camouflaged by the second fluorescence spectrum are large Therefore, the third identification value changes sensitively according to the difference between them, and the discrimination accuracy between various true synthetic fluorescence spectra and various false synthetic fluorescence spectra is improved.

In the above-described fluorescence spectrum identification methods A to C,
The first discriminant function, the second discriminant function, and the third discriminant function are preferably translationally symmetric functions.
In addition, the identification method of this structure is also called "the identification method D" below.

With the identification method D described above, the first weighted average value, the second weighted average value, and the third weighted average value can be easily calculated, and the first identification value, the second identification value, and the third identification value The weights of various weighted average values can be made uniform.

In the above fluorescence spectrum identification methods A to D,
Each of the first discriminant function, the second discriminant function, and the third discriminant function is preferably configured to have an approximate shape of the first fluorescence spectrum and the second fluorescence spectrum.
Hereinafter, the identification method of this configuration is also referred to as “identification method E”.

Here, as the “approximate shape of the first fluorescence spectrum and the second fluorescence spectrum”, for example, a function having substantially the same shape as the first fluorescence spectrum, a width that is the same as the half width of the first fluorescence spectrum is a half width. A Gaussian function based on the peak fitting of the first fluorescence spectrum, a function having substantially the same shape as the second fluorescence spectrum, a Gaussian function having a half-value width equal to the half-value width of the second fluorescence spectrum, A Gaussian function based on the peak fitting of the second fluorescence spectrum, a Gaussian function having an average value of the half width of the first fluorescence spectrum and the half width of the second fluorescence spectrum, and the first fluorescence spectrum and the second based on the peak fitting. An example is a Gaussian function in which the half value width is the average value of the half value width with the fluorescence spectrum.

With the above-described identification method E, the first identification value and the second identification value are values that can more accurately estimate the emission intensity of the true first fluorescence spectrum and the emission intensity of the true second fluorescence spectrum. , The first identification value, the second identification value, and the third identification value are respectively the difference between the first fluorescence spectrum and the fake fluorescence spectrum camouflaged with it, the true second fluorescence spectrum and the fake fluorescence camouflaged with it. Since the difference between the second fluorescence spectrum and the difference between the two can be reflected well, the discrimination accuracy with respect to a plurality of types of true synthetic fluorescence spectra and various types of true synthetic fluorescence spectra The discrimination accuracy from various false synthetic fluorescence spectra is further improved.

In the above-described fluorescence spectrum identification methods A to E,
The mode value of the first discrimination function is substantially the same as the dominant wavelength of the first fluorescence spectrum, and the mode value of the second discrimination function is substantially the same as the dominant wavelength of the second fluorescence spectrum. Preferably, the mode value of the third discriminant function is substantially the same as the intermediate value between the mode value of the first discriminant function and the mode value of the second discriminant function.
Hereinafter, the identification method having this configuration is also referred to as “identification method F”.

Here, “substantially the same” means that they are not intentionally different, and “substantially the same” means a case that exactly matches the dominant wavelength of the first fluorescence spectrum or the second fluorescence spectrum. This is not limited to the case, and implies a case where it does not exactly match the dominant wavelength of the first fluorescence spectrum or the measured second fluorescence spectrum due to a measurement error or the like.

With the above-described identification method F, the first identification value and the second identification value are values that can better estimate the emission intensity of the true first fluorescence spectrum and the emission intensity of the true second fluorescence spectrum. The first identification value equally reflects the difference between the first wavelength and the longer wavelength side of the first fluorescence spectrum between the first fluorescence spectrum and the fake fluorescence spectrum camouflaged as the first fluorescence spectrum. The value equally reflects the difference between the main wavelength of the second fluorescence spectrum between the true second fluorescence spectrum and the fake fluorescence spectrum camouflaged with the true second fluorescence spectrum, and the third wavelength and the third identification. The difference in the main wavelength side of the second fluorescence spectrum from the main wavelength of the first fluorescence spectrum between the first fluorescence spectrum and the fake fluorescence spectrum camouflaged by the first fluorescence spectrum, and the second fluorescence spectrum and the fake fluorescence spectrum camouflaged by the second fluorescence spectrum When In order to uniformly reflect the difference in the primary wavelength of the first fluorescence spectrum from the dominant wavelength of the second fluorescence spectrum, each other's discrimination accuracy with respect to a plurality of types of true synthetic fluorescence spectra and various types of true synthetic fluorescence spectra and various types The discrimination accuracy from the false synthetic fluorescence spectrum is further improved.

In the above-described fluorescence spectrum identification methods A to E,
Each of the plurality of types of synthetic fluorescence spectra is substantially the sum of the intensity of the first fluorescence spectrum with respect to the dominant wavelength of the first fluorescence spectrum and the intensity of the second fluorescence spectrum with respect to the dominant wavelength of the second fluorescence spectrum. It is preferable that the configuration is constant.
Hereinafter, the identification method of this configuration is also referred to as “identification method G”.

With the above identification method G, the ratio between the emission intensity of the first fluorescence spectrum and the emission intensity of the second fluorescence spectrum can be reliably varied. The sum of the first weighted average value and the second weighted average value for each of a plurality of types of true synthetic fluorescence spectra is substantially constant, and each of the first discriminating value and the second discriminating value is a true synthetic fluorescence spectrum and a false synthesis. Since it changes based on the third weighted average value that sensitively reflects the difference from the fluorescence spectrum, and the third identification value changes approximately in proportion to the third weighted average value, multiple types of true synthesis The discrimination accuracy with respect to the fluorescence spectrum and the discrimination accuracy between various true synthetic fluorescence spectra and various false synthetic fluorescence spectra are further improved. In addition, since the distribution range of the third identification value with respect to each of a plurality of types of true synthetic fluorescence spectra is reduced, various types of true synthetic fluorescence spectra and various types of false synthetic fluorescence spectra may be collectively determined. it can.

In the above fluorescence spectrum identification method G,
The first fluorescent material and the second fluorescent material have an intensity difference between the plurality of types of synthetic fluorescent spectra that is the smallest in a range between the dominant wavelength of the first fluorescent spectrum and the dominant wavelength of the second fluorescent spectrum. It is preferable that it is the structure selected so that may become the smallest.
Hereinafter, the identification method of this configuration is also referred to as “identification method H”.

With the above identification method H, since the distribution range of the third identification value for each of the plurality of types of true synthetic fluorescence spectra can be reduced, each of the first identification value, the second identification value, and the third identification value can be reduced. The difference between the true synthetic fluorescence spectrum and the false synthetic fluorescence spectrum can be reflected sensitively.

In the above-described fluorescence spectrum identification methods GH,
The mode value of the first discrimination function is substantially the same as the dominant wavelength of the first fluorescence spectrum, and the mode value of the second discrimination function is substantially the same as the dominant wavelength of the second fluorescence spectrum; It is preferable that the mode value of the third discriminant function is substantially the same as the wavelength having the smallest intensity difference between the plurality of types of synthetic fluorescence spectra.
Hereinafter, the identification method of this configuration is also referred to as “identification method I”.

With the above identification method I, since the distribution range of the third identification value for each of the plurality of types of true synthetic fluorescence spectra is further reduced, each of the first identification value, the second identification value, and the third identification value. However, the difference between the true synthetic fluorescence spectrum and the false synthetic fluorescence spectrum is reflected more sensitively.

In the above-described fluorescence spectrum identification methods GH,
The mode value of the first discrimination function is substantially the same as the dominant wavelength of the first fluorescence spectrum, and the mode value of the second discrimination function is substantially the same as the dominant wavelength of the second fluorescence spectrum; It is preferable that the mode value of the third discriminant function is substantially the same as the wavelength having the smallest maximum difference between the third discriminant values for each of the plurality of types of synthetic fluorescence spectra.
Hereinafter, the identification method of this configuration is also referred to as “identification method J”.

With the above identification method J, since the distribution range of the third identification value for each of the plurality of types of true synthetic fluorescence spectra is the smallest, each of the first identification value, the second identification value, and the third identification value. However, the difference between the true synthetic fluorescence spectrum and the false synthetic fluorescence spectrum is reflected more sensitively.

[Specific configuration]
A specific configuration according to the present invention will be described in detail with reference to the drawings. In addition, although a specific example is given and demonstrated, a design may be changed suitably, unless it deviates from the main point of this invention.

In the true article, as shown in FIG. 1, as the two types of fluorescent materials constituting the identification information, a set group of first ZAIS-based nanoparticles having the main wavelength λa (= 540 nm) ([first 1 fluorescent material] and a group of second ZAIS nanoparticles having a composition ratio different from that of the first ZAIS nanoparticle (λ2 (= 757 nm)) ([second fluorescent material]). A kind). The half-width (full width at half maximum; FWHM) of a fluorescence spectrum (a kind of [first fluorescence spectrum]) a ₁ · fa (λ) to a ₉ · fa (λ) based on a group of first ZAIS nanoparticles is Wa (≈130 nm), and the half-value width of the fluorescence spectrum (a kind of [second fluorescence spectrum]) b ₁ · fb (λ) to b ₉ · fb (λ) based on the group of second ZAIS nanoparticles is Wb (≈130 nm). The fluorescence spectra a ₁ · fa (λ) to a ₉ · fa (λ) and the fluorescence spectra b ₁ · fb (λ) to b ₉ · fb (λ) have a half-value width centered on the wavelength λa and the wavelength λb. In order to be characterized by a waveform that generally follows a Gaussian distribution of “130”, they are conveniently represented by a Gaussian function.

The compounding amount of the first ZAIS nanoparticle group is such that the intensity [arbitrary unit] at the wavelength λa with respect to the fluorescence spectrum a ₁ · fa (λ) to a ₉ · fa (λ) is “0.2 (= a ₁ ) ”to“ 1.8 (= a ₉ ) ”and adjusted so as to have any one of nine strengths at 0.2 intervals, and the amount of the aggregate group of the second ZAIS-based nanoparticles is The intensity [arbitrary unit] at the wavelength λb with respect to the fluorescence spectrum b ₁ · fb (λ) to b ₉ · fb (λ)) is “0.2 (= b ₁ )” to “1.8 (= b ₉ ). It has been adjusted so as to be any one of 9 levels of 0.2 intervals. However, the amount of the aggregate group of the second ZAIS-based nanoparticles is uniquely determined depending on the amount of the aggregate group of the first ZAIS-based nanoparticles. Specifically, the blending amount of the first ZAIS nanoparticle assembly group and the second ZAIS nanoparticle assembly group are shown in FIGS. 2 (A) to 2 (I). Thus, the intensity at the wavelength λa for the fluorescence spectra a ₁ · fa (λ) to a ₉ · fa (λ) and the intensity at the wavelength λb for the fluorescence spectra b ₁ · fb (λ) to b ₉ · fb (λ) The sum is constant (= 2.0), that is, [0.2 (= a ₁ ), 1.8 (= b ₉ )], [0.4 (= a ₂ ), 1.6 ( = B ₈ )], [0.6 (= a ₃ ), 1.4 (= b ₇ )], [0.8 (= a ₄ ), 1.2 (= b ₆ )], [1.0 (= A ₅ ), 1.0 (= b ₅ )], [1.2 (= a ₆ ), 0.8 (= b ₄ )], [1.4 (= a ₇ ), 0.6 ( = B ₃ )], [1.6 (= a ₈ ), 0.4 ( = B ₂ )] and [1.8 (= a ₉ ), 0.2 (= b ₁ )]. Thus, nine types of fluorescence spectra (one kind of [plural types of synthetic fluorescence spectra]) F ₁ (λ) (= a ₁ · fa (λ) + b ₉ · fb (λ) synthesized according to the combination thereof. ) To F ₉ (λ) (= a ₉ · fa (λ) + b ₁ · fb (λ)) represent the identification information corresponding to the identification information values “1” to “9”, respectively. Note that the fluorescence spectra a ₁ · fa (λ) to a ₉ · fa (λ) and the fluorescence spectra b ₁ · fb (λ) to b ₉ · fb (λ) have substantially the same shape (fa (λ ) = Fb (λ)), the combination of them is the total emission intensity of the fluorescence spectrum based on the first ZAIS-based nanoparticle aggregate group and the fluorescence spectrum based on the second ZAIS-based nanoparticle aggregate group. It is equivalent to the combination with the total emission intensity. As will be described later, in this embodiment, it is not necessary to satisfy the conditions on the same scale for these different combinations, that is, individual sizes of a ₁ to a ₉ and individual sizes of b ₁ to b ₉ . It does not depend on the size, and the combination ratio may be constant in each combination. For example, [0.2, 1.8], [0.8, 3.2], [1.8, 4.2], [3.2, 4.8], [5.0, 5.0 ], [7.2, 4.8], [9.8, 4.2], [12.8, 3.2] and [16.2, 1.8].

The aggregate group of the first ZAIS nanoparticles and the aggregate group of the second ZAIS nanoparticles are a group of arbitrary two types of ZAIS nanoparticles having different main wavelengths, and their half-value width or 1 / Considering 10 widths (full width corresponding to 1/10 of the maximum intensity; FWTM), various synthetic fluorescence spectra based on them have a double-headed peak shape, and two types of fluorescence spectra a ₁ · fa based on them (Λ) to a ₉ · fa (λ) and b ₁ · fb (λ) to b ₉ · fb (λ) are selected so as to overlap at least partially. Specifically, the main wavelength interval (λb−λa) between the fluorescence spectrum a ₁ · fa (λ) to a ₉ · fa (λ) and the fluorescence spectrum b ₁ · fb (λ) to b ₉ · fb (λ). ) Is a partial width Wal on the longer wavelength side than the dominant wavelength (wavelength λa) in the half-value width Wa of the fluorescence spectra a ₁ · fa (λ) to a ₉ · fa (λ) and the fluorescence spectrum b ₁ · fb (λ). Are at least larger than the sum of the partial width Wbs on the shorter wavelength side than the dominant wavelength (wavelength λb) in the half-value width Wb of b ₉ · fb (λ), and their combined fluorescence spectra F1 (λ) to F9 (λ) Are selected so as to have a double-headed peak shape substantially composed of peaks at two types of principal wavelengths (wavelength λa and wavelength λb). The main wavelength interval (λb−λa) is a portion on the longer wavelength side than the main wavelength (wavelength λa) in the 1/10 width Wa ′ of the fluorescence spectra a ₁ · fa (λ) to a ₉ · fa (λ). More than the sum of the width Wal ′ and the partial width Wbs ′ on the shorter wavelength side than the main wavelength (wavelength λb) in the 1/10 width Wb ′ of the fluorescence spectrum b ₁ · fb (λ) to b ₉ · fb (λ) Selected to be smaller. In this embodiment, the main wavelength interval (λb−λa) is selected to be larger than the larger partial width of the partial widths Wal ′ and Wbs ′. As shown in FIGS. 1 to 3, fluorescence spectra a ₁ · fa (λ) to a ₉ · fa (λ), b ₁ · fb (λ) to b based on a group of two types of ZAIS nanoparticles are used. _{When 9} · fb (λ) is well represented by a distribution function that is bilaterally symmetric about each principal wavelength (wavelength λa, wavelength λb) such as a Gaussian function of the same width and that is translationally symmetric in the wavelength direction Wa / 2 = Was = Wal = Wb / 2 = Wbs = Wbl, and Wa ′ / 2 = Was ′ = Wal ′ = Wb ′ / 2 = Wbs ′ = Wbl ′.

In addition, as shown in FIG. 3, the first ZAIS nanoparticle aggregate group and the second ZAIS nanoparticle aggregate group are an aggregate of any two types of ZAIS nanoparticles having different main wavelengths. The intensity difference at an arbitrary wavelength (the difference between the maximum intensity and the minimum intensity among the nine kinds of synthetic fluorescence spectra at an arbitrary wavelength) with respect to the nine types of synthetic fluorescence spectra based on them is between the two main wavelengths. The wavelength with the smallest odor is defined as the convergence wavelength, and the intensity difference at the convergence wavelength is defined as the convergence intensity difference, so that the convergence intensity difference is selected to be the smallest. As shown in FIG. 3, fluorescence spectra a ₁ · fa (λ) to a ₉ · fa (λ), b ₁ · fb (λ) to b ₉ · fb based on a group of two types of ZAIS nanoparticles. When (λ) is expressed by a distribution function that is bilaterally symmetric about the dominant wavelength such as a Gaussian function having the same width and is translationally symmetric in the wavelength direction, the convergent wavelength is the intermediate wavelength of these two dominant wavelengths (= (Λa + λb) / 2), and the convergence intensity difference is “0”. Two types of fluorescence spectra a ₁ · fa (λ) to a ₉ · fa (λ), b ₁ · fb (based on a group of first ZAIS nanoparticles and a group of second ZAIS nanoparticles) Even if λ) to b ₉ · fb (λ) do not show a bilaterally symmetric and translational distribution, the deviation of the symmetry is not large, so the convergence wavelength is the fluorescence spectrum a ₁ · fa (λ). Is a wavelength in the vicinity of an intermediate wavelength between the main wavelength (wavelength λa) of a ₉ · fa (λ) and the main wavelength (wavelength λb) of the fluorescence spectrum b ₁ · fb (λ) to b ₉ · fb (λ), Convergence intensity difference is larger than “0”, but is much larger than the case where the combination of the first ZAIS nanoparticle aggregate group and the second ZAIS nanoparticle aggregate group is not changed so as to satisfy the above condition. Small value.

A method for determining identification information for an article in which identification information has been written by including a group of first ZAIS nanoparticles and a group of second ZAIS nanoparticles as described above will be described. FIG. 4 is a flowchart illustrating an example of a method for calculating a set of identification values used for information determination and authenticity determination. FIG. 5 is a graph showing an example of the discrimination function.

First, a fluorescence spectrum (a kind of [measured fluorescence spectrum]) Fm (λ) is measured by irradiation with excitation light that can excite various ZAIS-based nanoparticles contained in the article (“fluorescence spectrum measurement process” S1).

Three types of weighted average values are calculated by changing the weights based on predetermined three types of discriminant functions for the measured fluorescence spectrum Fm (λ) (“weighted average value calculation process” S2). Specifically, as shown in FIG. 5, the dominant wavelength (wavelength λa) of the fluorescence spectra a ₁ · fa (λ) to a ₉ · fa (λ) is set to the mode (center), and the fluorescence spectrum a Gaussian function (a kind of [first discriminant function]) hα (λ) having a half-value width Wα (= Wa) substantially the same as the half-value width Wa of ₁ · fa (λ) to a ₉ · fa (λ) ) Is applied as a weighting function to calculate a weighted average value α (a kind of [first weighted average value]). Further, the dominant wavelength (wavelength λb) of the fluorescence spectrum b ₁ · fb (λ) to b ₉ · fb (λ) is set to the mode value (center), and the fluorescence spectrum b ₁ · fb (λ) to b ₉ · fb ( The following formula using a second Gaussian function (a kind of [second discriminant function]) hβ (λ) as a weighting function with a half-width Wβ (= Wb) substantially the same as the half-value width Wb of λ) A weighted average value β (a kind of [second weighted average value]) is calculated by the numerical calculation shown in FIG. Further, an intermediate wavelength ((λa + λb) between the dominant wavelength of the fluorescence spectrum a ₁ · fa (λ) to a ₉ · fa (λ) and the dominant wavelength of the fluorescence spectrum b ₁ · fb (λ) to b ₉ · fb (λ). ) / 2) is the mode value, and the half width Wa of the fluorescence spectrum a ₁ · fa (λ) to a ₉ · fa (λ) or the fluorescence spectrum b ₁ · fb (λ) to b ₉ · fb (λ) By a numerical operation represented by the following Equation 3 in which a third Gaussian function (a kind of [third discriminant function]) hγ (λ) having a width substantially the same as the half-value width Wb as a weight function is applied. The weighted average value γ (a kind of [third weighted average value]) is calculated.

Next, three types of identification values are calculated based on the calculated weighted average value α, weighted average value β, and weighted average value γ (“identification value calculation process” S3). Specifically, as shown in Equation 4 below, the weighted average value α is divided by the sum of the weighted average value α, the weighted average value β, and the weighted average value γ (α + β + γ) to obtain an identification value X ([first identification Similarly, as shown in Equation 5 below, the weighted average value β is divided by the sum (α + β + γ) to calculate the identification value Y (a type of [second identification value]). Similarly, as shown in the following Equation 6, the weighted average value γ is divided by the total sum (α + β + γ) to calculate the identification value Z (a kind of [third identification value]).

Next, a combination of the identification value X, the identification value Y, and the identification value Z and the nine types of synthetic fluorescence spectra F ₁ (λ) to F ₉ (λ) are calculated in advance, Based on the data table to determine the allowable range for each of Y and the identification value Z, the authenticity of the identification information written in the article and the determination of the identification information value are performed ("identification information / authentication determination process"). "S4). The data table includes median values X ₁ to X ₉ that determine an allowable range for the identification value _X and an allowable error range δ _X, and median values Y ₁ to Y ₉ for determining an allowable range for the identification value Y and The allowable error range δ _Y , the median values Z ₁ to Z ₉ for determining the allowable range for the identification value Z, and the allowable error range δ _Z are included.

Here, an allowable range for each of the identification value X, the identification value Y, and the identification value Z will be described. The measured fluorescence spectrum Fm (λ) has a relative intensity shift, a peak wavelength shift, and a peak width shift due to measurement errors with respect to the fluorescence spectra F ₁ (λ) to F ₉ (λ). Sometimes. FIG. 6 is a spectrum showing a relative intensity shift of the fluorescence spectrum. FIG. 6 shows the fluorescence spectrum F ₆ (λ) together with the fluorescence spectra Fm ′ (λ) and Fm ″ (λ) measured for the article in which the identification information corresponding to the identification information value 6 is written. As shown in Fig. 6, the fluorescence spectrum Fm '(λ) is measured by causing a deviation so that the relative intensity becomes small with respect to the fluorescence spectrum F ₆ (λ), or the fluorescence spectrum. Even if the fluorescence spectrum Fm ″ (λ) is measured such that the relative intensity with respect to F ₆ (λ) increases and the fluorescence spectrum Fm ″ (λ) is measured, each of the identification value X, the identification value Y, and the identification value Z is By being standardized as shown in Equations 4 to 6, the identification value X, the identification value Y, and the identification value Z are not substantially affected by the deviation.

On the other hand, when a shift in peak wavelength and a shift in peak width occur, the discriminating value X, the discriminating value Y, and the discriminating value Z are affected by the discrepancy. In consideration of misalignment, an allowable range for each of the identification value X, the identification value Y, and the identification value Z is determined. As a result, it is suppressed that the identification information is false even though the true identification information is written. Specific median values X ₁ to X ₉ , Y ₁ to Y ₉ , Z ₁ to Z ₉ and allowable error ranges δ _X , δ _Y , and δ _Z for each of the identification value X, the identification value Y, and the identification value _Z will be described. To do. In the following, the simulation is performed in the case where the fluorescence spectrum a ₁ · fa (λ) to a ₉ · fa (λ) and the fluorescence spectrum b ₁ · fb (λ) to b ₉ · fb (λ) are Gaussian functions. It demonstrates based on a result.

Table 1 below shows various identification values for a plurality of types of synthetic fluorescence spectra F ₁ (λ) to F ₉ (λ), a difference value between the various identification values, and a sum of absolute values of the difference values (= | ΔX | + | ΔY | + | ΔZ |; “SUM” in the table). FIG. 7 is a graph showing the sum of the difference values of various identification values and the absolute values of the difference values for a plurality of types of synthetic fluorescence spectra F ₁ (λ) to F ₉ (λ). In FIG. 7, the difference value ΔX of the identification value X is represented by a diamond mark, the difference value ΔY of the identification value Y is represented by a triangle mark, the difference value ΔZ of the identification value Z is represented by a square mark, and the difference value ΔX, The sum of the absolute values of ΔY and ΔZ (“SUM” in the figure) is represented by a cross. The same applies to FIGS. 8 and 9 described later.

As shown in Table 1 and FIG. 7, the median values X ₁ to X _{9 with} respect to the identification value X increase uniformly by “0.07” in accordance with the increase of the information identification value, The median values Y ₁ to Y ₉ are uniformly reduced by “0.07” in accordance with the increase of the information identification value, and the median values Z ₁ to Z _{9 with} respect to the identification value Z are independent of the identification information value. It is constant. Further, the sum of the absolute values of the difference values with respect to the identification value X, the identification value Y, and the identification value Z is substantially uniform by “0.14” in accordance with the increase and decrease of the information identification value from the reference value “6”. To increase. In FIG. 1 and FIG. 7, only the case where the half-value width Wa and the half-value width Wb are 130 nm and the half-value width of the discriminant function is also 130 nm is shown. Are different, but the median values X ₁ to X ₉ , median values Y ₁ to Y _9, and median values Z ₁ to Z ₉ show substantially the same tendency as those shown in Table 1 and FIG. In addition, the actual fluorescence spectrum a ₁ · fa (λ) to a ₉ · fa (λ) and the fluorescence spectrum b ₁ · fb (λ) to b ₉ · fb (λ) are not expressed by a strict Gaussian function. However, if the shape is almost similar to a Gaussian function, it shows the same tendency qualitatively. Therefore, the median values X ₁ to X ₉ , Y ₁ to Y ₉ , and Z ₁ to Z ₉ for each of the identification value X, the identification value Y, and the identification value Z are the same as the various identification values shown in Table 1. Set to a value.

Table 2 below shows various identification values, differences between various identification values, and differences between the half-value widths Wa and Wb of the fluorescence spectrum a ₆ · fa (λ) and the fluorescence spectrum b ₄ · fb (λ). Represents the sum of absolute values. Further, FIG. 8 shows changes in the difference values of various identification values and the sum of absolute values of the difference values with respect to changes in the half-value width of the fluorescence spectrum a ₆ · fa (λ) and the fluorescence spectrum b ₄ · fb (λ). It is a graph showing.

As shown in Table 2 and FIG. 8, the discriminant value X is monotonous as the half-value widths Wa and Wb of the fluorescence spectrum a ₆ · fa (λ) and the fluorescence spectrum b ₄ · fb (λ) increase. The identification value Y decreases monotonically, and the identification value Z increases monotonously. Conversely, as the half-value widths Wa and Wb decrease, the value of the identification value X increases monotonously, the value of the identification value Y increases monotonously, and the value of the identification value Z decreases monotonously. In addition, the sum of the absolute values of the difference values with respect to the identification value X, the identification value Y, and the identification value Z increases as the absolute value of the full width at half maximum increases. Although only the case of the information identification value 6 is shown in Table 2 and FIG. 8, the other identification information values 1 to 5 and 7 to 9 show substantially the same tendency. In addition, the actual fluorescence spectrum a ₁ · fa (λ) to a ₉ · fa (λ) and the fluorescence spectrum b ₁ · fb (λ) to b ₉ · fb (λ) are not expressed by a strict Gaussian function. However, if the shape is almost similar to a Gaussian function, it shows the same tendency qualitatively.

Table 3 below shows various identification values with respect to changes (peak shifts) of the main wavelengths of the fluorescence spectrum a ₆ · fa (λ) and the fluorescence spectrum b ₄ · fb (λ), and the difference values of the various identification values and their values. It represents the sum of absolute values of difference values. FIG. 9 shows the change in the difference value of various identification values and the sum of the absolute values of the difference values with respect to the change in the main wavelength of the fluorescence spectrum a ₆ · fa (λ) and the fluorescence spectrum b ₄ · fb (λ). It is a graph showing.

As shown in Table 3 and FIG. 9, the main wavelength of the fluorescence spectrum a ₆ · fa (λ) and the fluorescence spectrum b ₄ · fb (λ) are shifted to the longer wavelength side (increase in the main wavelength change amount). Accordingly, the value of the identification value X increases monotonously, the value of the identification value Y increases once, then monotonously decreases, and the value of the identification value Z decreases monotonously. In addition, according to the shift of the main wavelength of the fluorescence spectrum a ₆ · fa (λ) and the fluorescence spectrum b ₄ · fb (λ) to the short wavelength side (decrease in the change in the main wavelength), the value of the identification value X is temporarily After the decrease, the value monotonously increases, the value of the identification value Y monotonously decreases, and the value of the identification value Z monotonously increases. In the change of the main wavelength change amount, the identification value Y does not increase significantly because the maximum increase amount of the identification value Y in the shift of the main wavelength to the long wavelength side is about 0.006. In X, the maximum reduction amount of the identification value X in the shift of the dominant wavelength toward the short wavelength side is about 0.012, and does not decrease significantly. In addition, the sum of the absolute values of the difference values with respect to the identification value X, the identification value Y, and the identification value Z increases monotonously as the absolute value of the main wavelength change amount increases. Although only the information identification value 6 is shown in Table 3 and FIG. 9, the other information identification values 1 to 5 and 7 to 9 show substantially the same tendency. In addition, the actual fluorescence spectrum a ₁ · fa (λ) to a ₉ · fa (λ) and the fluorescence spectrum b ₁ · fb (λ) to b ₉ · fb (λ) are not expressed by a strict Gaussian function. However, if the shape is almost similar to a Gaussian function, it shows the same tendency qualitatively.

The change in the half width based on the measurement error is about 5% of the fluorescence spectrum a ₁ · fa (λ) to a ₉ · fa (λ), b ₁ · fb (λ) to b ₉ · fb (λ), The peak shift based on the measurement error (change in the measurement position of the main wavelength) is about 10 nm. Even when these measurement errors are combined with the measurement error or the slight difference based on the difference in the identification information value, the measurement error of the identification value X is less than “± 0.02”. Is less than “± 0.02”, and the measurement error of the identification value Z is less than “± 0.03”. Although the actual fluorescence spectrum a ₁ · fa (λ) to a ₉ · fa (λ) and the fluorescence spectrum b ₁ · fb (λ) to b ₉ · fb (λ) are not expressed by exact Gaussian functions, they are generally Gaussian. Because of the shape similar to the function, their measurement errors are almost the same. Therefore, the allowable error range [delta] _X for the identified value X, the allowable error range [delta] _Z for tolerance [delta] _Y and identification value Z for the identified value Y, respectively, "0.02", "0.02" and "0. 03 ".

If the combination of the identification value X, the identification value Y, and the identification value Z is within the allowable range defined by [X ₁ ± δ _X , Y ₁ ± δ _Y , Z ₁ ± δ _Z ], it is true identification information. It is determined that the information value is “1”. Similarly, within the allowable range defined by [X ₂ ± δ _X , Y ₂ ± δ _Y , Z ₂ ± δ _Z ], [X ₃ ± δ _X , Y ₃ ± δ _Y , Z ₃ ± δ _Z ] Within an allowable range defined by [X ₄ ± δ _X , Y ₄ ± δ _Y , Z ₄ ± δ _Z ], [X ₅ ± δ _X , Y ₅ ± δ _Y , Z ₅ ± [X ₇ ± δ _X , Y ₇ ± δ _Y ], within the allowable range defined by [δ _Z ], within the allowable range defined by [X ₆ ± δ _X , Y ₆ ± δ _Y , Z ₆ ± δ _Z ] , Z ₇ ± δ _Z ], within the allowable range defined by [X ₈ ± δ _X , Y ₈ ± δ _Y , Z ₈ ± δ _Z ] and [X ₉ ± δ _X , Y ₉ ± δ _Y , Z ₉ ± δ _Z ]], it is determined to be true identification information and the information values are “2”, “3”, “4”, “ 5 ”,“ 6 ”,“ 7 ”,“ 8 ”,“ 9 ” It is determined. Thereby, since the range of the identification value X and the range of the identification value Y according to various types of identification information values do not overlap each other, a plurality of types of identification information are reliably determined. Further, since the identification value X and the identification value Y are standardized so as not to depend on the intensity change in the measurement of the fluorescence spectrum as shown in the equations 4 to 6, the range of the identification value X and the identification value Y Can be set narrow, and a plurality of types of identification information are discriminated with high accuracy. Further, the discrimination accuracy is further improved by taking the discrimination value Z into consideration.

On the other hand, the identification value X, the combination of the identification value Y and identification value Z is not even within any range of _{_{_{[X i ± δ X, Y}}} i ± δ Y, Z i ± δ Z] (i = 1 ~ 9) For example, it is determined to be false identification information. As a result, the true fluorescence spectra (a ₁ · fa (λ) to a ₉ · fa (λ), b ₁ · fb () corresponding to any of the nine types of identification information values (“1” to “9”). When λ) to b ₉ · fb (λ)) are camouflaged, it is determined with high accuracy that the camouflaged fluorescence spectrum is different from any of the nine types of true fluorescence spectra.

Here, the authenticity determination of the fluorescence spectrum will be described in detail. FIG. 10 is an explanatory diagram showing a difference between an example of a true fluorescence spectrum and an example of a false fluorescence spectrum by narrow impersonation, and FIG. 11 shows an example of a true fluorescence spectrum and a false fluorescence spectrum by wide impersonation. FIG. 12 is an explanatory diagram showing a difference from an example, and FIG. 12 is an explanatory diagram showing a difference between an example of a true fluorescence spectrum and an example of a false fluorescence spectrum by a combined disguise of position and intensity. In addition, each of FIG. 10 (A), FIG. 11 (A), and FIG. 12 (A) shows the overall difference between the true fluorescence spectrum based on the fluorescent material A and the fluorescent material B and the disguise fluorescence spectrum. 10 (B), FIG. 11 (B), and FIG. 12 (B) each represent a partial difference between the fluorescence spectrum based on the fluorescent material A and the fluorescence spectrum camouflaged thereto, and FIG. 11C and FIG. 12C each show a partial difference between a fluorescence spectrum based on the fluorescent material B and a fluorescence spectrum camouflaged by the fluorescence spectrum. Further, in FIGS. 10 to 12, the portion that acts so that the weighted average value α, the weighted average value β, and the weighted average value γ decrease with respect to the true fluorescence spectrum is given a right-upward hatch, The parts that act in the direction in which they increase are hatched downwardly to the right.

In the case of narrow-fake camouflage, the weighted average value α and the identification value X are the true fluorescence spectrum a ₆ · fna (λ) and true as shown in FIG. 10 (A) and FIG. 10 (B). The difference based on the difference in half-value width from the fluorescence spectrum a ₆ · fa (λ) is reflected. Similarly, as shown in FIG. 10A and FIG. 10C, the weighted average value β and the identification value Y are obtained by comparing the false fluorescence spectrum b ₄ · fna (λ) and the true fluorescence spectrum b ₄ · The difference based on the difference in half width from fb (λ) is reflected. Further, as shown in FIGS. 10A to 10C, the weighted average value γ and the identification value Z are expressed as a false fluorescence spectrum Fn ₆ (λ) and a true fluorescence spectrum F ₆ (λ). differences, in particular, the true fluorescence spectra _{a 6} · the true fluorescence spectra _a 6 · fa _(λ) of the main wavelength than (wavelength [lambda] a) false in the long wavelength side fluorescence spectra _a 6 · fna _(λ) The difference based on the difference in half width from fa (λ) and the false fluorescence spectrum b ₄ · fnb (λ) on the shorter wavelength side than the main wavelength (wavelength λb) of the true fluorescence spectrum b ₄ · fb (λ) The composite difference resulting from the difference based on the difference in half-value width from the true fluorescence spectrum b ₄ · fb (λ) is reflected. Specifically, in the case of narrow camouflage, each of the weighted average value α, the weighted average value β, and the weighted average value γ decreases monotonously according to the decrease in the half width, but is shown in Table 2 above. As described above, the identification value X and the identification value Y increase monotonously by the normalization shown in

Equations

4 and 5, and the identification value Z decreases monotonously by the normalization shown in Equation 6.

Further, in the case of wide camouflage, the weighted average value α and the identification value X are expressed as a false fluorescence spectrum a ₆ · fwa (λ) and true as shown in FIG. 11 (A) and FIG. 11 (B). This reflects the difference based on the difference in half-value width from the fluorescence spectrum a ₆ · fa (λ). Similarly, as shown in FIG. 11A and FIG. 11C, the weighted average value β and the identification value Y are obtained by comparing the false fluorescence spectrum b ₄ · fwa (λ) and the true fluorescence spectrum b ₄ · The difference based on the difference in half width from fb (λ) is reflected. In addition, as shown in FIGS. 11A to 11C, the weighted average value γ and the identification value Z are the false fluorescence spectrum in the case of the false fluorescence spectrum Fw ₆ (λ) by the wide disguise. The difference between Fw ₆ (λ) and the true fluorescence spectrum F ₆ (λ), more specifically, false fluorescence on the longer wavelength side than the main wavelength (wavelength λa) of the true fluorescence spectrum a ₆ · fa (λ) More than the main wavelength (wavelength λb) of the difference between the spectrum a ₆ · fwa (λ) and the true fluorescence spectrum a ₆ · fa (λ) based on the difference in half width and the true fluorescence spectrum b ₄ · fb (λ) The composite difference resulting from the difference based on the difference in half width between the false fluorescence spectrum b ₄ · fwb (λ) and the true fluorescence spectrum b ₄ · fb (λ) on the short wavelength side is reflected. Specifically, in the case of wide camouflage, each of the weighted average value α, the weighted average value β, and the weighted average value γ increases monotonously according to the increase in the half width, as shown in Table 2 above. As described above, the identification value X and the identification value Y are monotonously decreased by the normalization shown in

Equations

4 and 5, and the identification value Z is monotonously increased by the normalization shown in Equation 6.

Accordingly, at least one identification value of the identification value X, the identification value Y, and the identification value Z for the false fluorescence spectrum F ₆ w (λ) in the case of narrow-width camouflage or wide-width camouflage corresponds to the true fluorescence spectrum F ₆ (λ). If it falls outside the allowable range, it can be determined that the fluorescence spectrum is not true F ₆ (λ). In the present embodiment, as shown in Table 2, the fluorescence spectra a ₆ .fna (λ) and a ₆ · fwa () constituting the false fluorescence spectra F ₆ n (λ) and F ₆ w (λ) are used. λ) and fluorescence spectra b ₄ · fnb (λ), b ₄ · fwb (λ) and the fluorescence spectrum a ₆ · fa (λ) and fluorescence spectrum b ₄ · fb (λ) constituting the true fluorescence spectrum When the difference from the half-value width is 30 nm or more, it is determined that the fluorescence spectrum is impersonated.

In the case of fake fluorescence spectra F ₆ n (λ) and F ₆ w (λ) of narrow or wide camouflage with respect to the fluorescence spectrum F ₆ (λ) whose identification information value is “6”, the discrimination value X Becomes a value within the permissible range of the identification value X for the fluorescence spectra having different identification information values, for example, the fluorescence spectrum F ₇ (λ) and the fluorescence spectrum F ₅ (λ), or the identification value Y is different from the identification information value. In some cases, the value is within the allowable range of the identification value Y for the fluorescence spectrum. However, as shown in Table 1, the identification value X and the identification value Y change with opposite polarities as the identification information value changes, that is, the identification value X increases when the identification value X increases. While Y decreases, the identification value Y increases when the identification value X decreases, while the identification value X and the identification value Y change in the same polarity in the case of narrow and wide camouflage. Therefore, even if one of the identification value X and the identification value Y is within the allowable range corresponding to the other identification information value, the other is always outside the allowable range corresponding to the other identification information value. Therefore, the fluorescence spectrum _{F 6} (lambda) fluorescence spectra _F 6 n _(λ) false by narrow impersonation and wide impersonation _{for, F} 6 w _(λ) of any of the other true fluorescence spectrum _{F 1 (λ)} ~ _F ₅ (λ) and F ₇ (λ) to F ₉ (λ) are not determined. In addition, although the case of the narrow-width impersonation or the wide-width impersonation with respect to the fluorescence spectrum F ₆ (λ) having the identification information value “6” has been described, the fluorescence spectra F ₁ (λ) to F ₅ ( The same applies to the case of narrow-width camouflage and wide-camera camouflage for λ), F ₇ (λ) to F ₉ (λ).

In addition, in the case of a fake fluorescence spectrum a ₆ ′ · fsa (λ) due to composite camouflage, as shown in FIGS. 12 (A) and 12 (B), the weighted average value α is mainly false. The difference of the fluorescence spectrum a ₆ ′ · fsa (λ) and the true fluorescence spectrum a ₆ · fa (λ) based on the difference in the position of the main wavelength, the emission intensity, and the half width is reflected. Similarly, as shown in FIG. 12A and FIG. 12C, the weighted average value β is mainly composed of the false fluorescence spectrum b ₄ ′ · fsa (λ) and the true fluorescence spectrum b _4. It reflects the difference based on the difference of the main wavelength position, emission intensity and half-value width from fb (λ). In addition, as shown in FIGS. 12A to 12C, the weighted average value γ is a false fluorescence spectrum a ₆ ′ · fsa (λ) and a true fluorescence spectrum a ₆ · fa (λ). The position of the main wavelength, the difference in emission intensity and half width, and the position of the main wavelength, emission intensity and half of the false fluorescence spectrum b ₄ ′ · fsb (λ) and the true fluorescence spectrum b ₄ · fb (λ) It will reflect complex differences resulting from differences based on price range differences. In the case of compound camouflage, the identification value X, the identification value Y, and the identification value Z change variously based on the selection of the fluorescent material and the selection of the blending amount, but the false fluorescence spectrum Fs ₆ A combination of the identification value X, the identification value Y, and the identification value Z for the fluorescence spectrum F ₁ (λ) to F ₉ (λ) in which the combination of the identification value X, the identification value Y, and the identification value Z with respect to (λ) is true. Since it is extremely rare to be included in any of the above, their fluorescence spectra can be distinguished well.

As described above, according to the fluorescence spectrum identification method of the present embodiment, true fluorescence spectra having different identification information values can be distinguished from each other based on the combination of the identification value X, the identification value Y, and the identification value Z. It is possible to discriminate between the true fluorescence spectrum and the false fluorescence spectrum due to the narrow camouflage, the wide camouflage or the composite camouflage.

Further, according to the fluorescence spectrum identification method of the present embodiment, the identification value X and the identification value Y are the emission intensity and the fluorescence spectrum b _{1 of the} fluorescence spectra a ₁ · fa (λ) to a ₉ · fa (λ), respectively. Standards in which the emission values of fb (λ) to b ₉ · fb (λ) can be satisfactorily estimated and the identification value X, the identification value Y, and the identification value Z are expressed by Equations 4 to 6, respectively. does not depend on the overall emission intensity of the fluorescence spectrum _{_{F 1 (λ) ~ F 9}} (λ) by reduction, identification value X, identification value Y and identification value Z is, respectively, fluorescence spectra _a 1 · fa _(λ) ~ A ₉ · fa (λ) and the fake fluorescence spectrum camouflaged with it in the vicinity of the wavelength λa, the fluorescence spectrum b ₁ · fb (λ) to b ₉ · fb (λ) and the fake camouflaged with it The difference in the vicinity of the wavelength λb from the fluorescence spectrum, and the fluorescence spectrum Vector _{_{a 1 · fa (λ) ~}} a 9 · fa (λ) and the fluorescence spectrum of the difference and the true near the wavelength λa different wavelengths λγ the fluorescence spectrum of the false _{b 1 · fb (λ) ~} b 9 · In order to change according to both the difference between the wavelength λb of fb (λ) and its fake fluorescence spectrum and the difference between the different wavelengths λγ, the combination of the identification value X, the identification value Y, and the identification value Z Based on these, nine types of fluorescence spectra F ₁ (λ) to F ₉ (where the ratio of the emission intensity based on the group of first ZAIS nanoparticles and the intensity of the emission based on the second group of ZAIS nanoparticles differ) λ) can be discriminated with high accuracy from each other, and the fluorescence spectra F ₁ (λ) to F ₉ (λ) and the fake fluorescence spectrum camouflaged with any of them can be discriminated with high accuracy and simplicity. In addition, since each of the identification value X, the identification value Y, and the identification value Z does not depend on the overall emission intensity of the fluorescence spectra F ₁ (λ) to F ₉ (λ), the article containing the identification information is small. Even when the irradiation area of the excitation light for exciting the ZAIS nanoparticle cannot be secured sufficiently, or when the flat region where the excitation light is irradiated cannot be secured, various determinations can be performed with high accuracy.

Further, the main wavelengths (wavelength λa) of the fluorescence spectra a ₁ · fa (λ) to a ₉ · fa (λ) so that the nine types of fluorescence spectra F ₁ (λ) to F ₉ (λ) have a double-headed peak shape. And the main spectrum (wavelength λb) of the fluorescence spectra b ₁ · fb (λ) to b ₉ · fb (λ) are separated by a predetermined distance or more, so that the fluorescence spectrum b ₁ · fb (λ) at the discrimination value X The contribution from b ₉ · fb (λ) is satisfactorily reduced so that the emission intensity of the fluorescence spectrum a ₁ · fa (λ) to a ₉ · fa (λ) can be estimated with higher accuracy and the discrimination value The contribution from the fluorescence spectra a ₁ · fa (λ) to a ₉ · fa (λ) in Y is well reduced, and the emission intensity of the fluorescence spectra b ₁ · fb (λ) to b ₉ · fb (λ) is further increased. The value can be estimated well, and the identification value X, the identification value Y, and the identification value Z are Is, fluorescence spectra _{_{a 1 · fa (λ) ~}} a 9 · fa (λ), in _{b 1 · fb (λ) ~} b 9 · fb (λ) and higher precision of various differences between the fluorescence spectrum of false Will be reflected. Thus, the discrimination accuracy of the nine types of fluorescence spectra F ₁ (λ) to F ₉ (λ) and the discrimination between the various fluorescence spectra F ₁ (λ) to F ₉ (λ) and the various false synthetic fluorescence spectra The accuracy is further improved.

Further, according to the method for discriminating the fluorescence spectrum of this embodiment, the mode value (wavelength λγ) of the discrimination function hγ (λ) is the fluorescence spectrum a ₁ · fa (λ) to a ₉ · fa (λ) and the fluorescence spectrum. b ₁ · fb (λ) to b ₉ · fb (λ) are in the overlapping wavelength region, and the fluorescence spectrum a ₁ · fa (λ) to a ₉ · fa (λ) and the fake fluorescence spectrum disguised as it And the fluorescence spectrum b ₁ · fb (λ) to b ₉ · fb (λ) overlap with a portion having a large difference between the fake fluorescence spectrum camouflaged with the fluorescence spectrum b ₁ · fb (λ) to b ₉ · fb (λ). It changes sensitively according to the difference between them, and the discrimination accuracy between the fluorescence spectra F ₁ (λ) to F ₉ (λ) and the false fluorescence spectrum camouflaged by any of them is improved.

Further, according to the fluorescence spectrum identification method of the present embodiment, the discrimination function hα (λ), the discrimination function hβ (λ), and the discrimination function hγ (λ) are translationally symmetric shapes, so that the weighted average value α, weighted The average value β and the weighted average value γ can be easily calculated, and the weights of the various weighted average values α, β, and γ in the identification value X, the identification value Y, and the identification value Z can be made uniform.

Further, according to the fluorescence spectrum identification method of the present embodiment, each of the identification function hα (λ) and the identification function hβ (λ) is applied to the approximate shape fa (λ) of the fluorescence spectrum based on the fluorescent material A and the fluorescent material B. Since the approximate shape fb (λ) of the fluorescence spectrum is based on the identification value X and the identification value Y, the emission intensity of the fluorescence spectrum a ₁ · fa (λ) to a ₉ · fa (λ) and the fluorescence spectrum b ₁ · The light emission intensities of fb (λ) to b ₉ · fb (λ) can be estimated more satisfactorily, and the identification value X, the identification value Y, and the identification value Z are respectively represented by fluorescence spectra a ₁ · fa (λ ) To a ₉ · fa (λ) and the fake fluorescence spectrum camouflaged with it, the fluorescence spectrum b ₁ · fb (λ) to b ₉ · fb (λ) and the fake fluorescence spectrum camouflaged with it Good reflection of the differences and the differences between them So it can, the fluorescence spectrum _{F 1 (λ) ~ F 9} (λ) mutual recognition accuracy and fluorescence spectra F ₁ for _{_{(λ) ~ F 9 (λ}} ) and the fluorescence spectrum of false disguised in any of them Is further improved.

Further, according to the fluorescence spectrum identification method of the present embodiment, the mode value (wavelength λα) of the identification function hα (λ) is the dominant wavelength of the fluorescence spectrum a ₁ · fa (λ) to a ₉ · fa (λ) ( The mode (wavelength λβ) of the discrimination function hβ (λ) is substantially the same as the wavelength λa), and the dominant wavelength (wavelength λb) of the fluorescence spectrum b ₁ · fb (λ) to b ₉ · fb (λ) And the mode value (wavelength λγ) of the discriminant function hγ (λ) is an intermediate value between the mode value of the discriminant function hα (λ) and the mode value of the discriminant function hβ (λ) (( λα + λβ) / 2 = (λa + λb) / 2), and the identification value X and the identification value Y are the emission intensity and fluorescence of the fluorescence spectra a ₁ · fa (λ) to a ₉ · fa (λ). with a better estimate of values and emission intensity of the spectral _{_{b 1 · fb (λ) ~}} b 9 · fb (λ), the identification value X fluorescence spectrum _{1 · fa (λ) ~ a} 9 · fa (λ) and equally reflect the differences in both the short wavelength side and the long wavelength side with respect to the wavelength λa of the fluorescence spectrum of spoofed false thereto, identification value Y Reflects equally the difference between the short wavelength side and the long wavelength side with respect to the wavelength λb of the fluorescence spectrum b ₁ · fb (λ) to b ₉ · fb (λ) and the fake fluorescence spectrum camouflaged with it. And the discriminating value Z is different from the fluorescence spectrum a ₁ · fa (λ) to a ₉ · fa (λ) and the false fluorescence spectrum camouflaged with the wavelength λa on the longer wavelength side and the fluorescence spectrum b ₁ · In order to evenly reflect the difference between fb (λ) to b ₉ · fb (λ) and the false fluorescence spectrum camouflaged with it on the shorter wavelength side than the wavelength λb, the fluorescence spectra F ₁ (λ) to F ₉ mutual recognition accuracy and fluorescence spectra for _{(λ) F 1 (λ)} ~ F 9 lambda) and the discrimination accuracy of the fluorescence spectrum of false disguised in any of them can be further improved.

Further, according to the method for identifying a fluorescence spectrum of the present embodiment, each of the nine types of fluorescence spectra F ₁ (λ) to F ₉ (λ) has a fluorescence spectrum a ₁ · fa (λ) to a ₉ · fa (λ ) At the main wavelength (wavelength λa) and the intensity at the main wavelength (wavelength λb) of the fluorescence spectra b ₁ · fb (λ) to b ₉ · fb (λ) are substantially constant, Their intensity ratio is definitely different. Further, the sum of the weighted average value α and the weighted average value β for each of the nine types of fluorescence spectra F ₁ (λ) to F ₉ (λ) is substantially constant, and each of the identification value X and the identification value Y is the fluorescence spectrum F. ₁ (λ) to F ₉ (λ) and a weighted average value γ that sensitively reflects the difference between the false fluorescence spectra camouflaged by any of them, and the third identification value is a weighted average value γ To the nine types of fluorescence spectra F ₁ (λ) to F ₉ (λ), and the fluorescence spectra F ₁ (λ) to F ₉ (λ) and any one of them. The accuracy of discrimination from the false fluorescence spectrum camouflaged by is further improved.

In the present embodiment, the allowable range for the identification value Z is changed for each of the various fluorescence spectra F ₁ (λ) to F ₉ (λ). F ₁ (λ) to F ₉ (λ) are substituted with a common tolerance, and various fluorescence spectra F ₁ (λ) to F ₉ (λ) and a fake fluorescence spectrum camouflaged by any of them It is also possible to make a configuration in which these are discriminated collectively.

In the present invention, the dominant wavelength (wavelength λa) of the fluorescence spectrum a ₁ · fa (λ) to a ₉ · fa (λ) and the fluorescence spectrum b ₁ · fb (λ) to b ₉ · fb (λ) Fluorescent material so that the maximum intensity difference between the smallest fluorescence spectra F ₁ (λ) to F ₉ (λ) is the smallest in the range between the wavelength λa and the wavelength λb. It can also be set as the structure by which A and the fluorescent material B are selected. With this configuration, since the distribution range of the identification value Z for each of the nine types of fluorescence spectra F ₁ (λ) to F ₉ (λ) can be reduced, the identification value X, the identification value Y, and the identification value Z can be reduced. It is possible to sensitively reflect the difference between the fluorescence spectra F ₁ (λ) to F ₉ (λ) and the fake fluorescence spectrum camouflaged in any of them.

Further, in this embodiment, various differences are determined based on the identification value X, the identification value Y, and the identification value Z. However, the sum of the difference values of the identification value X, the identification value Y, and the identification value Z is variously disguised. The spectrum in this case may be configured to make a true / false determination by using a unique increase.

In the present invention, the mode value (wavelength λα) of the discrimination function hα (λ) is substantially equal to the main wavelength (wavelength λa) of the fluorescence spectrum a ₁ · fa (λ) to a ₉ · fa (λ). And the mode value (wavelength λβ) of the discrimination function hβ (λ) is substantially the same as the dominant wavelength (wavelength λb) of the fluorescence spectrum b ₁ · fb (λ) to b ₉ · fb (λ). The mode (wavelength λγ) of the discrimination function hγ (λ) is substantially the same as the wavelength having the smallest maximum intensity difference among the nine types of fluorescence spectra F ₁ (λ) to F ₉ (λ). You can also With this configuration, the distribution range of the identification value Z for each of the nine types of fluorescence spectra F ₁ (λ) to F ₉ (λ) is further reduced, so that the first identification value, the second identification value, and the Each of the three identification values more sensitively reflects the difference between the fluorescence spectra F ₁ (λ) to F ₉ (λ) and the false fluorescence spectrum camouflaged by any of them.

In the present invention, the mode value (wavelength λα) of the discrimination function hα (λ) is substantially equal to the main wavelength (wavelength λa) of the fluorescence spectrum a ₁ · fa (λ) to a ₉ · fa (λ). And the mode value (wavelength λβ) of the discrimination function hβ (λ) is substantially the same as the dominant wavelength (wavelength λb) of the fluorescence spectrum b ₁ · fb (λ) to b ₉ · fb (λ). The mode value (wavelength λγ) of the discrimination function hγ (λ) is substantially equal to the wavelength with the smallest maximum difference between the discrimination values Z for each of the nine types of fluorescence spectra F ₁ (λ) to F ₉ (λ). It can also be set as the same structure. With this configuration, since the distribution range of the identification value Z for each of the nine types of fluorescence spectra F ₁ (λ) to F ₉ (λ) is the smallest, the identification value X, the identification value Y, and the identification value Z Each more sensitively reflects the difference between the fluorescence spectra F ₁ (λ) to F ₉ (λ) and the fake fluorescence spectrum camouflaged in any of them.

The present invention is suitable for discrimination of identification information based on the blending of fluorescent materials and discrimination of counterfeits.

S1: Fluorescence spectrum measurement process S2: Weighted average value calculation process S3: Identification value calculation process S4: Identification information / authenticity determination process

Claims

A plurality of types of synthesis in which the combined waveform of the first fluorescent spectrum based on the first fluorescent material and the second fluorescent spectrum based on the second fluorescent material is different depending on the blending difference between the first fluorescent material and the second fluorescent material. Fluorescence spectra are discriminated from each other, and the intensity of the first fluorescence spectrum at the dominant wavelength and the second fluorescence spectrum are different from one of the plurality of types of synthetic fluorescence spectra, although the overall waveform is different A fluorescence spectrum identification method for distinguishing between a false fluorescence spectrum having substantially the same intensity at the dominant wavelength and each of the plurality of types of synthetic fluorescence spectra,
Each of the first fluorescent material and the second fluorescent material is a group of semiconductor nanoparticles,
A part of the first fluorescence spectrum and a part of the second fluorescence spectrum constituting each of the plurality of types of synthetic fluorescence spectra overlap,
A single-head peak shape having a distribution function of a single-head peak shape having a mode value in the vicinity of the main wavelength of the first fluorescence spectrum as a first discriminant function and a mode having a mode value in the vicinity of the main wavelength of the second fluorescence spectrum. Is a second discriminant function, and a single-peak distribution function having a mode between the mode value of the first discriminant function and the mode value of the second discriminant function is a third discriminant function. As a discrimination function, a first weighted average value obtained by weighting the measured fluorescence spectrum measured from the identification target with the first discrimination function is calculated, and the second discrimination function is used for the measured fluorescence spectrum. Calculating a weighted second weighted average value, and calculating a third weighted average value weighted by the third discriminant function for the measured fluorescence spectrum;
The first weighted average value is normalized by the sum of the first weighted average value, the second weighted average value, and the third weighted average value to calculate a first identification value for the measured fluorescence spectrum, and the second weighted value Normalizing the average value with the sum to calculate a second identification value for the measured fluorescence spectrum, and normalizing the third weighted average value with the sum to calculate a third identification value for the measured fluorescence spectrum;
The combination of the first identification value, the second identification value, and the third identification value is an allowable range for the predetermined first identification value associated with each of the plurality of types of synthetic fluorescence spectra and a predetermined first value. When the measurement fluorescence spectrum is included in any one combination of the tolerance range for the two identification values and the tolerance range for the predetermined third identification value, the measured fluorescence spectrum is one of the plurality of types of synthetic fluorescence spectra. Is determined to be the same as the synthetic fluorescence spectrum corresponding to the combination, and if it is not included in any combination of the allowable ranges associated with each of the plurality of types of synthetic fluorescence spectra, A method for identifying a fluorescence spectrum, wherein the measured fluorescence spectrum is determined to be the fake fluorescence spectrum.
2. The fluorescence spectrum identification method according to claim 1, wherein each of the plurality of types of synthetic fluorescence spectra has a double-headed peak shape.
The mode of the fluorescence spectrum according to claim 1 or 2, wherein the mode value of the third discrimination function is in a wavelength region where the first fluorescence spectrum and the second fluorescence spectrum overlap.
The fluorescence spectrum identification method according to claim 1, 2, or 3, wherein the first discrimination function, the second discrimination function, and the third discrimination function are translationally symmetric functions.
The first discrimination function, the second discrimination function, and the third discrimination function are approximate shapes of the first fluorescence spectrum and the second fluorescence spectrum, respectively. Identification method of fluorescence spectrum.
The mode value of the first discriminant function is substantially the same as the dominant wavelength of the first fluorescence spectrum;
The mode of the second discriminant function is substantially the same as the dominant wavelength of the second fluorescence spectrum;
The mode value of the third discriminant function is substantially the same as the intermediate value between the mode value of the first discriminant function and the mode value of the second discriminant function;
The method for identifying a fluorescence spectrum according to any one of claims 1 to 5.
Each of the plurality of types of synthetic fluorescence spectra is substantially the sum of the intensity of the first fluorescence spectrum with respect to the dominant wavelength of the first fluorescence spectrum and the intensity of the second fluorescence spectrum with respect to the dominant wavelength of the second fluorescence spectrum. The method for identifying a fluorescence spectrum according to any one of claims 1 to 5, wherein:
The first fluorescent material and the second fluorescent material have an intensity difference between the plurality of types of synthetic fluorescent spectra that is the smallest in a range between the dominant wavelength of the first fluorescent spectrum and the dominant wavelength of the second fluorescent spectrum. The method for identifying a fluorescence spectrum according to claim 7, wherein is selected to be the smallest.
The mode value of the first discriminant function is substantially the same as the dominant wavelength of the first fluorescence spectrum;
The mode value of the second discriminant function is substantially the same as the dominant wavelength of the second fluorescence spectrum;
The mode value of the third discriminant function is substantially the same as the wavelength having the smallest intensity difference between the plurality of types of synthetic fluorescence spectra;
The method for identifying a fluorescence spectrum according to claim 7 or 8.
The mode value of the first discriminant function is substantially the same as the dominant wavelength of the first fluorescence spectrum;
The mode value of the second discriminant function is substantially the same as the dominant wavelength of the second fluorescence spectrum;
The mode value of the third discriminant function is substantially the same as the wavelength with the smallest maximum difference between the third discriminant values for each of the plurality of types of synthetic fluorescence spectra;
The method for identifying a fluorescence spectrum according to claim 7 or 8.