FR2866460A1 - Document e.g. bank note, securing method, involves associating safety light sign producing determined light response to document, and incorporating marker generating light transmission ray into safety sign - Google Patents

Abstract

The method involves associating a safety light sign (100) that produces a determined light response in response to an excitation radiation, to a document (10). The light response is produced partially according to a wide spectrum. A marker is incorporated into the safety sign, where the marker is able to generate a light transmission ray in response to another excitation radiation. Independent claims are also included for the following: (A) a safety document such as bank note (B) a method for authenticating a safety document (C) an authentication machine for implementing safety document authenticating method.

Description

The present invention relates generally to the manufacture and

  authentication of security documents.

  More specifically, the invention relates to a method of securing a document, comprising associating the document with a luminescent safety sign which produces a determined light response in response to a first excitation radiation, said luminous response being performing at least partially in a broad spectrum.

  The invention also relates to a security document obtained by such a method.

  And the invention also relates to a method of authenticating such a security document, and an associated authentication machine.

  It is specified that broad spectrum is understood to mean a spectrum of wavelengths which is different from a single line, covering without interruption a longer range of wavelengths.

  And a ray is defined as a radiation essentially limited to a very narrow wavelength range, ie covering a range of wavelengths of the order of about 20 nm only.

  Safety methods of the type mentioned above are already known.

  It is thus known, for example, to associate with a security document such as a banknote a luminescent security sign which produces a response in the visible spectrum in response to excitation radiation which may be in the ultra violet spectrum. (UV).

  The authentication of the document results from the comparison of the light response of said document exposed to the excitation radiation with a stored expected response.

  This authentication can be performed by a machine.

  It can also be performed in some cases directly by a human observer (especially with the naked eye).

  This type of process thus offers a certain level of security.

  The object of the invention is to further increase the level of security that can be obtained.

  In order to achieve this object, the invention provides a method for securing a document, comprising associating the document with a luminescent safety sign which produces a determined light response in response to a first excitation radiation, said light response being effected at least partially according to a broad spectrum, characterized in that the method also comprises the incorporation in said safety sign of at least one marker capable of generating, in response to a second excitation radiation, at least a light emission line.

  Preferred but nonlimiting aspects of the security method according to the invention are the following: where the light emission line (s) generated by the said marker (s) is ( are) outside the wavelength range covered by said broad spectrum of the security sign response, where the light emission line (s) generated by the said (s) s) marker (s) is (are) located in the wavelength range covered by said broad spectrum of the security sign response, É the light emission lines generated by said (s) s) marker (s) are distributed both in and out of the wavelength range covered by said broad spectrum of the security sign response, E the first and second excitation radiation are identical and merged into one and the same excitation radiation, e said excitation radiation is a radiation whose spectrum is centered around a wavelength e less than or equal to a value of the order of 370 nm, e said broad spectrum of said light response corresponds to a range of wavelengths included in the visible spectrum, E said broad spectrum of said light response corresponds to a range of wavelengths between about 500 nm and about 560 nm, 2866460 3 Is carried out a coding with several light emission lines associated with one or more marker (s) incorporated (s) said security sign, E incorporates said security sign indicates a same dopant in association with different matrices, each pair formed by said dopant and one of the matrices corresponding to a respective marker producing at least one respective light emission line, so that with the same dopant the at least two different light emission lines in said security sign, E said security sign is associated with a dye, E said dye performs a filtering in a light said wavelength constants constitute a band-pass filter for the wavelengths of the responses of said security sign, E at least one light emission line of said one or more markers ( s) incorporated in the security sign at its wavelength comprised in the wavelengths of said band-pass filter.

  The invention also proposes a security document such as a bank note, the document comprising a luminescent security sign capable of producing a determined light response in response to a first excitation radiation, said light response being effected at least partially according to a broad spectrum, characterized in that said security sign incorporates at least one marker capable of generating, in response to a second excitation radiation, at least one light emission line.

  Preferred but non-limiting aspects of such a security document are the following: where the light emission line (s) generated by the said marker (s) is (are ) located outside the wavelength range covered by said broad spectrum of the security sign response, where the light emission line (s) generated by the said (s) ) marker (s) is (are) located in the wavelength range covered by said broad spectrum of the security sign response, É the light emission lines generated by the said (s) ) marker (s) are distributed both in and outside the wavelength range covered by said broad spectrum of the security sign response, E the various components of the security sign are able to be excited by radiation single excitation which thus corresponds to both the first and second excitation radiation, E said security sign comprises several m arqueurs capable of generating under the effect of the second excitation radiation different light emission lines, E said different lines form a code recognizable by an authentication machine, E at least some of said markers are made from the same dopant, by associating this same dopant with different respective matrices.

  The invention also relates to a method for authenticating such a security document, as well as an authentication machine for implementing such an authentication method.

  The authentication method is characterized in that it comprises the possibility of performing an authentication: E in a simplified mode, in which: - the document is illuminated with said first excitation radiation, - the light response of the security sign to said first excitation radiation, with a broadband sensor means, for seeking only the component of the response of said security sign which is defined by a broad spectrum, 2866460 5 - the response collected is compared with a response stored broad spectrum spectrum, and, if the two compared responses satisfy a given correspondence, the authenticity of the sign according to the simplified mode, E and / or in an advanced mode, is concluded in which: the document is illuminated with said second excitation radiation, - the light response of the safety sign to said second excitation radiation is collected, with a sensor means capable of detecting the the presence of isolated light lines, in order to search for the component of the response of said security sign which is defined by at least one light emission line, - the collected response is compared with a stored expected line response (s), and if the two compared answers satisfy a given match, the authenticity of the sign in the advanced mode is concluded.

  Preferred but nonlimiting aspects of this authentication method are the following: where the light emission line (s) generated by the said marker (s) is (are) located outside the wavelength range covered by said broad spectrum of the security sign response, where the light emission line (s) generated by the said (s) marker (s) is (are) located in the wavelength range covered by said broad spectrum of the security sign response, É the light emission lines generated by the said (s) marker (s) are distributed both in and outside the wavelength range covered by said broad spectrum of the security sign response, É in the advanced mode, the simplified mode authentication operations are also performed, The first and second excitation radiation are identical so that the document is illuminated with the same excitation radiation for the implementation of the two authentication modes.

  É for authentication in simplified mode, the luminous response of the security sign is collected at said first excitation radiation without perceiving the presence of isolated light lines, É the simplified mode authentication is performed visually by a human operator, É l ' authentication in simplified mode is performed by machine, E said machine is provided with means capable of characterizing a colorimetry of the component of the response of the security sign which is defined by a broad spectrum, E the advanced mode authentication is performed by a machine.

  The authentication machine according to the invention is characterized in that it comprises: É means for illuminating the document, É means for acquiring the luminous response of the security sign, É Memory storage means at least one expected response, 20 É means for comparing the collected light response and a stored expected response.

  Preferred but non-limiting aspects of such a machine are the following: The machine acquisition means comprise means for individually collecting each line generated by the marker (s) incorporated in the sign. document security, É the acquisition means of the machine comprise a plurality of sensors each for detecting a line around a wavelength individually associated with said sensor, the meeting of the lines associated with the different sensors means of acquisition covering at least a part of the visible spectrum, É said lines associated with the different sensors of the acquisition means are of the order of 20 nm wide, E the meeting of said lines associated with the different sensors substantially covers the entire visible spectrum, The means for acquiring the machine further comprise means for collecting the response of said security sign which is defined by a broad spectrum, É the illumination means are capable of emitting excitation radiation centered around a wavelength less than or equal to a value of the order of 370 nm, É the acquisition means of the luminous response of the security sign are able to collect a luminous response in the visible spectrum, É the means of acquisition of the luminous response of the security sign are able to collect a luminous response in a range of wavelengths between about 500 nm and about 560 nm.

  Other aspects, objects and advantages of the invention will become more apparent upon reading the following description, with reference to the accompanying drawings, in which: FIG. 1 is a diagrammatic representation of a security document such as a bank note, produced according to the invention, É Figures 2a and 2b are two schematic representations illustrating two authentication modes of such a security document:> Figure 2a corresponding to a simplified authentication mode, Figure 2b corresponding to an advanced authentication mode.

  FIG. 3 diagrammatically represents means for authenticating such a document.

  Referring firstly to Figure 1, there is shown schematically a security document 10 such as a bank note according to the invention.

  The document 10 comprises at least one region 100 corresponding to a luminescent security sign.

  The region 100 may have been associated with the document by any technique known per se (printing of a luminescent ink, integration of a sheet element or a luminescent wire, etc.).

  As is known, the region 100 of the document 10 is able to produce, when exposed to excitation radiation 210 (as shown in FIG. 2a), a response 220 of determined characteristics.

  More precisely, the response 220 is a broad-spectrum response, as is symbolized in the diagram of FIG. 2a (the spectrum of this response covers a wavelength range substantially greater than a range of the order of 20 nm).

  It should be noted that this diagram (like that of FIG. 2b) represents on the ordinates the intensity of a response, as a function of wavelengths 9, which appear on the abscissa.

  The characteristics of the response 220 depend on the characteristics of the excitation radiation 210, and the luminescent properties of the security sign constituted by the region 100.

  In the context of the invention, however, the response of the security sign of the region 100 to excitation radiation is not limited to such a response 220 as shown in FIG. 2a.

  Indeed, as shown in FIG. 2b, the same safety sign of the region 100 is able to emit a response 221, and this in response to a second excitation radiation 211.

  The response 221 consists of at least one line (three lines in the case of the representation of Figure 2b).

  It is specified that the two excitation radiations 210 and 211 may be identical and coincide in one and the same excitation radiation.

  In such a case, the representation of FIGS. 2a and 2b should be replaced by a single radiation in which the responses 220 and 221 are superimposed, this radiation being emitted in response to the single excitation radiation.

  In any case, even in the case where the first and second excitation radiations are combined into a single excitation radiation, so that the response of the sign 100 is in fact a single response to this single excitation radiation. two components of the response of the security sign 100 will be distinguished: É Component 220 which is carried out according to a broadband spectrum, É Component 221 which takes place in one or more lines.

  We will thus designate by 220 and 221: E the two respective responses in the case where these two responses 10 are effectively distinct because resulting from two distinct excitation radiations, E is the two components of a response that is strictly unique because resulting from a single excitation radiation (or because two excitation radiations are certainly implemented, but are directed simultaneously to the sign 100).

  In the same way, we will speak in this text of first and second excitation radiation, bearing in mind that these radiations can be confused in a single radiation (in this case, each of the terms first excitation radiation and second radiation of excitation refers to this unique excitation radiation).

  As indicated above, the response 221 to the second excitation radiation is not a broad spectrum response.

  On the contrary, it is a response consisting of a light line, or a plurality of distinct lines.

  These lines may all be outside the wavelength range covered by the broad spectrum of the response 220 to the first excitation radiation.

  They may also be in the wavelength range covered by said broad spectrum of the security sign response to the first excitation radiation.

  In this case, the intensity of the response of each line will be substantially greater than the intensity of the broad spectrum response to the first excitation radiation, for the window of wavelengths corresponding to the line.

  It is also possible to provide that the response 221 comprises a plurality of light lines, distributed both within the wavelength range covered by the broad-spectrum response to the first excitation radiation, and outside this range. of wavelengths.

  It is this latter variant which is schematically illustrated in FIG. 2b (the graph associated with this figure taking in dotted line the broad spectrum response to the first excitation radiation 210).

  To obtain such a double response (responses 220 and 221), the security sign 100 has particular luminescent properties.

  This sign comprises in fact at least one marker capable of generating, in response to the second excitation radiation, the light emission line (s) of the response 221.

  This marker (s) has therefore been incorporated into the sign 100, by any method known per se.

  And this marker (s), which makes it possible to define the response 221, is (are) sensitive to the second excitation radiation.

  It is specified that the term "marker" refers to the combination of a dopant with a given matrix (a matrix being defined as the physical environment hosting the dopant).

  As has been said, the first and second excitation radiations can constitute a single excitation radiation.

  These excitation radiations can be centered in the UV domain.

  A single excitation radiation can thus, in one embodiment of the invention, correspond to a wavelength spectrum centered around a wavelength of the UV spectrum.

  This wavelength may for example be less than or equal to a value of the order of 370 nm.

  The wide spectrum response 220 preferably corresponds to a range of wavelengths within the visible spectrum.

  For example, this broad response spectrum may be expected to span a wavelength range of about 500 nm to about 560 nm.

  As has been said, each line of the response 221 to the second excitation radiation is obtained by integrating a specific marker into the security sign 100.

  Each marker can thus generate at least one line for the response 221.

  It is specified that it is possible to obtain different respective markers by associating a same dopant to different respective matrices.

  In this case, each pair formed by the dopant and one of the matrices corresponds to a different marker, each marker generating as said at least one line in the response 221.

  It is thus possible to use the same doping ion on matrices of different characteristics (type of matrix, stoichiometry of the matrix, etc.) so that the response lines on the different matrices are shifted (the difference between lines being preferably of a width for example of at least 10 nm).

  In a particular embodiment (which corresponds to an excitation performed around a wavelength of the order of 800 nm and to a response in wavelengths of the order of 1050 to 1060 nm - and differs thus examples of wavelengths which have just been given and which will be developed later in this text), it is possible, for example, to use a dopant in the form of Neodyne ions on the one hand on a matrix of type YLF and thus obtain a first marker whose response to a laser excitation of wavelength 800 nm is an emission line centered on 1054 nm, and on the other hand on a YAG type matrix and thus obtain a first marker whose response to the same laser excitation of wavelength 800 nm is an emission line centered on 1064 nm.

  In this way, at least two different light emission lines can be generated with the same dopant in the response 221 of the security sign 100.

  Moreover, the security sign 100 may be associated with a dye. A dye is defined here as means making it possible to ensure a light filter function, according to a desired wavelength window.

  The dye may correspond to a substance or a powder integrated in the sign of the region 100, or to any other optical filtering means which passes only the radiation of a given range of wavelengths.

  This dye can in particular perform a filtering in a window of wavelengths of the visible spectrum.

  The dye thus constitutes a band-pass filter for the wavelengths of the responses of the security sign 100.

  This filtering function makes it possible to eliminate any undesirable components of the responses 220 and / or 221.

  It can be expected that when employing such a dye, at least one emission line of the response 221 has its wavelength included in the wavelength window of the dye bandpass filter.

  In this case, the dye allows the sign 100 to emit the line in question, and this line may be detected by suitable authentication means.

  It has been said that answer 221 was made from at least one line, and that it could consist of several distinct lines.

  It is also possible to carry out from a given combination of different lines an encoding of the response 221.

  And one can also consider declining this coding for example according to different groups of security documents.

  It is thus possible to code: E with a first general code the response 221 of a first group of notes (corresponding for example to a first face value), É with a second general code a second group of notes, etc. And within each of these groups, each ticket may optionally be associated with a specific code of the response 221, this specific code corresponding to a particular declination of the general code associated with the group to which the ticket belongs.

  In all cases, the authentication of the response 221 will be done according to the same general principle as the authentication of the response 220.

  The response 221 will thus be collected (by means which will be described below), then compared to an expected reference response which is stored in the authentication means (for example in an authentication machine, or in a server to which the authentication machine is connected).

  We will now describe the main steps of the authentication process of the document 10, with particular reference to Figure 3.

  This figure schematically represents an authentication device 30 for the document 10.

  The device 30 is fixed, the document 10 moving past sensor means of this device in the direction of the arrow F. The device 30 is provided with means for generating the excitation radiation 210 and 211.

  In the representation of FIG. 3, these means correspond to two different light sources 310 and 311.

  However, as has been said, the two radiations can be confused in this case the device 30 may comprise only a single source generating a single excitation radiation, which corresponds to both the radiation 210 and 211.

  In one embodiment, the illumination means of the machine are thus able to emit excitation radiation centered around a wavelength less than or equal to a value of the order of 370 nm.

  In all cases, the radiation 210 and 211 are directed towards a fixed area to be crossed by the security sign 100 of the document 10.

  It is specified that it is possible alternatively to provide that the document 10 is fixed, and that it is the device 30 that is mobile relative to the document.

  When the security sign 100 arrives in the zone illuminated by the radiation 210 and 211, this security sign produces two respective responses 220, 221 to the said radiation 210, 211 (or a response comprising the two components 220, 221, in the case where the excitation radiation is unique or more generally in the case where the two excitation radiation is emitted simultaneously on the region 100).

  It has been seen above that the security document 10 (which may be for example a banknote) has a luminescent security sign 100 to which at least one marker is incorporated so as to generate in addition a response (or component response) 220 broad-spectrum response (or response component) 221 in at least one line, in response to excitation radiation 211.

  It is possible to implement the authentication of such a document in a simplified mode, and / or in an advanced mode.

  It is recalled that the first excitation radiation and the second excitation radiation are designated: E each of the respective radiations 210 and 211 if these radiations are distinct, É the single excitation radiation in the case where the radiation 210 and 211 are confused.

  It is also recalled that the response of the sign 100 to the first excitation radiation is a response 220 which is carried out according to a broad spectrum, and the response of this same sign to the second excitation radiation is a response 221 which is performed according to one or more lines.

  These two answers can be in the visible domain.

  And these two responses can actually be two components of a single response, in the case where the excitation radiation is itself unique or more generally, in the case where the excitation radiation is emitted simultaneously towards the document to authenticate.

  The simplified authentication mode involves the first excitation radiation 210 and the corresponding broadband response 220.

  In this simplified mode, the following operations are carried out: The sign 100 of the document is illuminated with the first excitation radiation. The luminous response of the security sign 100 is collected at this first excitation radiation with a sensor means. broadband, in order to search only for the component of the response of said security sign which is defined by a broad spectrum (i.e., response 220), E. comparing the collected response with a stored broad expected spectrum response, and, if the two compared answers satisfy a given correspondence, the authenticity of the sign in the simplified mode is concluded.

  The broadband sensor means may be a single sensor, or a set of sensors. He is in any case able to collect the answer 220.

  The advanced mode involves the second excitation radiation 211 and the corresponding line response (s) 221.

  In this advanced mode, the following operations are carried out: Illuminates 100 of the document with the second excitation radiation, the light response of the safety sign 100 is collected to said second excitation radiation, with a sensor means capable of detecting the presence of isolated light lines, in order to search for the component of the response of said security sign which is defined by at least one light emission line, and comparing the collected response with a stored expected line response (s) and if the two compared answers satisfy a given match, the authenticity of the sign in the advanced mode is concluded.

  The sensor means able to detect the presence of isolated light lines can here again be a single sensor.

  It can also be in the form of a plurality of sensors. It can thus include a sensor for detecting each of the lines of the expected response 221.

  And it is possible that the broadband sensor means and the line sensor means are combined into one and the same sensor means. It will thus be possible for this sensor means to gather a plurality of sensors known as line sensors, individually associated with the detection of the response of the sign 100 along a given line.

  In this case, the set of line sensors can cover a spectrum of continuous wavelengths, the windows of wavelengths associated with the different sensors can be adjacent.

  The spectrum covered by the combination of the wavelength windows associated with the different sensors may in particular cover at least part of the visible spectrum. And more generally, responses 220 and 221 can thus cover at least part of the visible spectrum.

  These responses may in particular be in wavelengths between about 500 nm and about 560 nm.

  It is also possible that this spectrum substantially covers the entire visible spectrum.

  The lines associated with the different line sensors can correspond to windows of wavelengths of the order of 20 nm wide.

  The different sensor means are integrated in the authentication machine 30, a schematic illustration of which is given in FIG.

  In this illustration, the sensor means are thus in the form of a plurality of line sensors 32.

  The machine also comprises means 33 which are connected to the sensor means 32.

  These means 33 are capable of performing comparison and authenticity diagnostic operations which will be described later in this text. The machine 30 thus comprises the following elements: É Means 310, 311 for illuminating the security sign 100 of the document 10, É Means 32 for acquiring the luminous response of the security sign 100, É Storage means at least one expected response, means for comparing the collected light response and a stored expected response.

  The means 33 comprise the means for memorizing the expected response (s) and the comparison means (or may come into contact with a remote memory for example at a central server).

  The means 33 are thus able to compare the response 220 collected by the sensor means to a stored broadband response, and to give an indication of good comparison (correspondence of the collected response and the stored response) or poor comparison.

  And these means 33 are also able to perform the same operations for the response 221, as a function of the comparison with a response to a line (s) stored.

  As has been said, the acquisition means 32 of the machine may comprise individual sensors making it possible to individually collect a response of the document along one line, in particular to detect the line (s) generated by the marker (s) incorporated into the security sign of the document, during authentication in advanced mode.

  Advanced Mode authentication can be done at the same time as Easy Mode authentication.

  It is also possible to implement only a simplified mode authentication, in which the sign 100 is illuminated with the first authentication radiation 210 and only the presence and the conformity of the response 220 are detected.

  In this case, the authentication is done without searching in the light response of the security sign to said first excitation radiation the presence of isolated light lines.

  This possibility may in particular be implemented by simple authentication machines which do not include a line sensor means.

  It will thus be possible to use, for such authentication carried out in simplified mode only, existing machines provided only with broadband sensors.

  Such broadband sensors may for example only allow the detection and recognition of a colorimetry of the response 220 of the security sign which is defined by a broad spectrum.

  And the means 33 of the machines used only for authentication in simplified mode thus do not necessarily include means for comparing a response 221, or even means for storing an expected line response (s).

  Simplified mode authentication can also be performed visually by a human operator.

  Authentication in advanced mode is necessarily carried out by machine.

  In the case where the lines of the response 221 form a code, the authentication machine 30 is associated not only with means for detecting and authenticating said response, but also with means for recognizing this code.

  These means can be incorporated in the means 33. They can also be deported to a central server with which the machine is able to communicate.

  Providing specific means for advanced mode authentication significantly enhances the security level associated with the document.

  And the combination of responses 220 and 221 makes it possible at one and the same time: E to allow recognition of the response 220 of the document with simple authentication machines, provided only with broadband sensor means, or even by an observer looking at the camera. the document illuminated by excitation radiation 210. The security documents according to the invention can thus be authenticated (like some existing documents) on the sole basis of the recognition of the broadband response 220, E to allow additional security by the response 221. It will be noted in particular that a counterfeiter wanting to produce false documents 10 provided with a sign 100, and having detected on a genuine document only the broadband response 220, will reproduce in its imitation of the sign 100 that the means making it possible to generate the broadband response 220, and will not integrate in this imitation of the sign 100 of marker (s) making it possible to generate a no answer to line (s) 221.

Claims (42)

  A method of securing a document, comprising associating the document with a luminescent safety sign which produces a determined light response in response to a first excitation radiation, said light response being at least partially in accordance with a broad spectrum, characterized in that the method also comprises the incorporation in said safety sign of at least one marker capable of generating, in response to a second excitation radiation, at least one light emission line.   2. Method according to the preceding claim, characterized in that the ray (s) of light emission generated (s) said (s) marker (s) is (are) located (s) out of the wavelength range covered by said broad spectrum of the security sign response.   3. Method according to claim 1, characterized in that the ray (s) of light emission generated by the said marker (s) is (are) located in the wavelength range covered by said broad spectrum of the security sign response.   4. Method according to claim 1, characterized in that the light emission lines generated by the said marker (s) are distributed both inside and outside the wavelength range covered by said broad spectrum of the security sign response.   5. Method according to one of the preceding claims, characterized in that the first and the second excitation radiation are identical and merged into one and the same excitation radiation.   6. Method according to the preceding claim, characterized in that said excitation radiation is a radiation whose spectrum is centered around a wavelength less than or equal to a value of the order of 370 nm.   7. Method according to one of the preceding claims, characterized in that said broad spectrum of said light response corresponds to a range of wavelengths included in the visible spectrum.   8. Method according to the preceding claim, characterized in that said broad spectrum of said light response corresponds to a range of wavelengths between about 500 nm and about 560 nm.   9. Method according to one of the preceding claims, characterized in that a coding is carried out with several light emission lines associated with one or more marker (s) incorporated (s) said security sign.   10. Method according to one of the preceding claims, characterized in that incorporating at said security sign a same dopant in combination with different matrices, each pair formed by said dopant and a matrix corresponding to a respective marker producing at least one line respective light emission, so that with the same dopant is generated at least two different light emission lines in said security sign.   11. Method according to one of the preceding claims, characterized in that said security sign is associated with a dye.   12. Method according to the preceding claim, characterized in that said dye performs a filtering in wavelengths of the visible spectrum.   13. Method according to the preceding claim, characterized in that said dye forms in the wavelengths a band-pass filter for the wavelengths of the responses of said security sign.   14. Method according to the preceding claim, characterized in that at least one light emission line of said marker (s) incorporated (s) security sign has its wavelength included in the wavelengths of said filter bandpass.   A security document such as a bank note, the document comprising a luminescent security sign capable of producing a determined light response in response to a first excitation radiation, said light response being effected at least partially according to a spectrum. broad, characterized in that said security sign incorporates at least one marker capable of generating, in response to a second excitation radiation, at least one light emission line.   16. Security document according to the preceding claim, characterized in that the ray (s) of light emission generated by the said marker (s) is (are) located (s) outside the wavelength range covered by said broad spectrum of the security sign response.   17. Security document according to claim 15, characterized in that the light emission line (s) generated by the said marker (s) is (are) located (s) in the wavelength range covered by said broad spectrum of the security sign response.   18. Security document according to claim 15, characterized in that the light emission lines generated by the said marker (s) are distributed both in and outside the wavelength range. covered by said broad spectrum of the security sign response.   19. Security document according to one of the four preceding claims, characterized in that the various components of the security sign are able to be excited by a single excitation radiation which thus corresponds to both the first and the second radiation of 'excitation.   20. Security document according to one of the five preceding claims, characterized in that said security sign comprises several markers capable of generating under the effect of the second excitation radiation different light emission lines.   21.Safety document according to the preceding claim, characterized in that said different lines form a recognizable code by an authentication machine.   22. Security document according to one of the two preceding claims, characterized in that at least some of said markers are made from the same dopant, by associating the same dopant to different respective matrices.   23. A method for authenticating a security document obtained by a method according to one of claims 1 to 12, characterized in that said authentication method comprises the possibility of performing an authentication: É according to a simplified mode, wherein: - the document is illuminated with said first excitation radiation, - the luminous response of the security sign is collected at said first excitation radiation, with a broadband sensor means, in order to search only the component of the response of said security sign which is defined by a broad spectrum, - the collected response is compared with a stored broad expected spectrum response, and, if the two compared responses satisfy a given match, the authenticity of the sign according to the mode is determined simplified, and / or in an advanced mode, in which: - the document is illuminated with said second excitation radiation, - the light response is collected; euse of the security sign to said second excitation radiation, with a sensor means adapted to detect the presence of isolated light lines, in order to search for the component of the response of said security sign which is defined by at least one emission line. luminous, - the collected response is compared with a stored expected line response (s), and, if the two compared responses satisfy a given match, the authenticity of the sign in the advanced mode is concluded.   24. Authentication method according to the preceding claim, characterized in that the ray (s) of light emission generated by the said marker (s) is (are) located (s) ) out of the wavelength range covered by said broad spectrum of the security sign response.   25. Authentication method according to claim 23, characterized in that the light emission line (s) generated by the said marker (s) is (are) located (s). ) in the wavelength range covered by said broad spectrum of the security sign response.   26. Authentication method according to claim 23, characterized in that the light emission lines generated by the said marker (s) are distributed both in and outside the range of lengths. wave covered by said broad spectrum of the security sign response.   27. Authentication method according to one of the four preceding claims, characterized in that in the advanced mode is also carried out the authentication operations of the simplified mode.   28. Authentication method according to one of the five preceding claims, characterized in that the first and second excitation radiation are identical so that the document is illuminated with the same excitation radiation for the implementation of two authentication modes.   29. Authentication method according to one of the six preceding claims, characterized in that for authentication in simplified mode the light response of the security sign to said first excitation radiation is collected without perceiving the presence of isolated light lines.   30. Authentication method according to the preceding claim, characterized in that the authentication in simplified mode is performed visually by a human operator.   2866460 26 31. Authentication method according to one of claims 27 to 30, characterized in that the authentication in simplified mode is performed by machine.   32. Authentication method according to the preceding claim, characterized in that said machine is provided with means capable of characterizing a colorimetry of the component of the response of the security sign which is defined by a wide spectrum.   33. Authentication method according to one of the ten preceding claims, characterized in that the authentication in advanced mode is performed by a machine.   34. Authentication machine for implementing an authentication method according to one of the preceding claims, characterized in that the machine comprises: É means of illumination of the document, É means of acquisition of the luminous response of the security sign, É Means for storing at least one expected response, 20 É Means for comparing the collected luminous response and a stored expected answer.   35. Authentication machine according to the preceding claim, characterized in that the acquisition means of the machine comprise means for collecting individually each line generated by the marker (s) incorporated (s) to the security sign of the document.   36. Authentication machine according to the preceding claim, characterized in that the acquisition means of the machine comprise a plurality of sensors each for detecting a line around a wavelength individually associated with said sensor, the meeting the lines associated with the different sensors of the acquisition means covering at least part of the visible spectrum.   37. Authentication machine according to the preceding claim, characterized in that said lines associated with the different sensors of the acquisition means are of the order of 20 nm wide.   38. Authentication machine according to one of the two preceding claims, characterized in that the meeting of said lines associated with the different sensors substantially covers the entire visible spectrum.   39. Authentication machine according to one of the five preceding claims, characterized in that the acquisition means of the machine further comprise means for collecting the response of said security sign which is defined by a wide spectrum.   40. Authentication machine according to one of the six preceding claims, characterized in that the illumination means are capable of emitting excitation radiation centered around a wavelength less than or equal to a value of the order. 370 nm.   41. Authentication machine according to one of the seven preceding claims, characterized in that the means for acquiring the light response of the security sign are able to collect a light response in the visible spectrum.   42. Authentication machine according to the preceding claim, characterized in that the means for acquiring the light response of the security sign are able to collect a light response in a wavelength range of between approximately 500 nm and approximately 560 nm.