The method of application on the subject of subsurface marking
(57) Abstract:The method of applying to the object (14) subsurface marking includes the steps of direction at the object surface (14) of the beam of laser radiation (12), for which the material of the object (14), essentially opaque, and the energy of the beam absorbed by the surface of the object sufficient for the formation of localized stresses in the subject (14) at points spaced from the said surface, without the formation of any appreciable change in the surface, and localized voltage formed so usually invisible to the naked eye, but can become visible in polarized light. The described method will provide the problematic detection marked a potential infringer, and falsification and destruction of this marking. 3 C. and 20 C.PP.f-crystals, 6 ill. The invention relates to a method of applying on the subject of subsurface marking, invisible to the naked eye but readable with polarized light.Many products are packaged in containers made of glass or plastics, and for many years there was a need to create ways markirovki the b marking can have a wide range of applications, including to combat shadow trade.In the past for the application of indelible marking manufacturer could rely almost exclusively on the application of marks on the surface of the objects. However, this type of code is causing the problem lies in the fact that the marks can be destroyed when you remove part of the surface, which is marked, or they can be fabricated by applying identical spoofed marking on the container.To overcome these problems, the applicant has developed a method and device for supply of the subject subsurface marking described in international publication N 92/03297 B 41 M 5/24. The described method includes the steps of direction on the surface of the object beam with high energy density, for which the material of this subject is transparent, and focus the beam to a point located at some distance from the surface inside the subject so as to cause a localized ionization of the material and create a mark in the form of areas of increased opacity to electromagnetic radiation without any visible changes on the surface. It provides the advantage that the received is having additional benefits, it would be desirable to mark that is invisible to the naked eye. Thus, the potential infringer will not only have problems removing and fake marking, but also for it is problematic to detect the applied marking.Closest to the claimed method according to the essential features and achieved technical result is the method of applying on the subject of subsurface marking, known from U.S. patent N 3657085, B 01 J 1/10, 08.04.72.The known method describes the application of subsurface marking using the electron beam, when it is indicated for use as an alternative of a laser beam. The objective of this U.S. patent is a method of marking articles such as glasses lens, so that normally, this label is not visible, but is visible if necessary. For this purpose, electronic or laser beam is directed onto the mask is placed on the lens of the glasses so that part of the beam passes through the slits in the mask and gets on the lens material points. The beam scatters from a collision with the molecules of the material of the lens, resulting in kinetic energy of the beam is absorbed in the form of heat, which about can become visible when the double refraction in polarized light.In U.S. patent N 3657085 reference is made to the possibility of applying the laser beam in connection with the labeling items with colored mass, for example, items containing the mass of the chromophore, and not objects, simply by having on the surface of the colored layer. I mean the chromophore, which absorbs the laser radiation and thus produces sufficient localized heat to the formation of permanent areas of tension in the substance. Since mark is at a distance from the surface of a substance, it must be at least partially transparent to laser radiation and to allow the laser radiation to penetrate into the substance to the desired depth.The basis of the invention is to create a way of drawing on the subject of subsurface marking by which the latter is not visible to the naked eye.The problem is solved in that in the method of applying on the subject of subsurface marking, comprising the steps of direction on the surface of the object beam of laser radiation, with localized voltage generated in such a way that is invisible to the naked eye but can be observed in polarized light,and absorbed by the surface of the object sufficient to create a localized stresses in the object at points spaced from the said surface, without the formation of any appreciable change in the surface, and localized voltage generated in such a way, usually invisible to the naked eye, but is visible under polarized light.This implementation of the method according to the invention, provides the problematic detection marked a potential infringer, and falsification and destruction of the label.Preferably, the body of the subject contained a material having a thermal conductivity approximately equal to thermal conductivity of the glass.Mainly formed by localized stresses markings may represent one or more numbers, letters, or symbols, or a combination of both.It is recommended that the beam of laser radiation to concentrate for the formation of illuminated spots on the surface of the object, and the spot can be moved relative to the surface are marked, thus ensuring the creation of a marking formed by localized stresses, Meuse ciremai surface so to form an elongated area of localized stress, which when observed in polarized light has the appearance of a line.Alternatively, the spot can be moved relative to the marked object for forming a number of spaced apart regions of localized stress, which when observed in polarized light have the form of a set of points.In particular, a number of spaced apart regions of localized stress can be formed by moving the spot with constant speed relative to the detection object and the periodic change in the power density of the beam.Alternatively, a series of spaced apart regions of localized stress form while maintaining the power density of the beam is essentially constant and the change of time, during which the spot lights consistently placed on the points of the surface.When this spot is moved relative to the marked object at a speed which varies periodically from 0 to 3 m/s, maintaining the average speed in the range of 2 to 3 m/sPreferably, when the energy of the beam absorbed serial t the significance is the power density in the spot up to 10 kW/cm2.It is recommended that a beam of laser radiation to irradiate a mask placed in front of a marked object, and the mask has one or more slits for forming a marking formed by localized stresses and having a predefined configuration.Preferably, when the beam of laser radiation generated with the help of CO2-laser.You want the material marked subject, would be transparent to electromagnetic radiation with wavelengths in the visible range.In an alternative embodiment, the material of marked object can be opaque to electromagnetic radiation with wavelengths in the visible range, with localized voltage is controlled with the help of optical devices with the corresponding wavelength of the electromagnetic spectrum.In accordance with the second aspect of the present invention the body is made of a material having a thermal conductivity approximately equal to thermal conductivity of the glass, as well as having a plot localized stresses at a distance of some interval about what atragene pass from one edge of the lens-shaped marking, essentially convex cross-section.Mainly, when the body of the subject is transparent to electromagnetic radiation with wavelengths in the visible range.In particular, the body of the subject can be made of glass or plastic.Alternatively, the body of the subject is opaque to electromagnetic radiation with wavelengths in the visible range, with localized voltage can only be observed using optical instruments with the corresponding wavelength in the electromagnetic spectrum.Mostly, when marking formed by localized stresses, represents one or more numbers, letters, or symbols, or a combination of both.Preferably, when the body of the object is a container.A number of embodiments of the present invention will now be described based on examples with reference to the accompanying drawings:
Fig. 1 is a diagram of a device capable of implementing the described method;
Fig. 2 - scheme of distribution of electric energy through the device according to Fig. 1;
Fig. 3 - schematic representation of the interaction of laser beam with the material specific formation of a number of marks in the form of a matrix of points;
Fig. 5 is an example of a subsurface mark is formed in a way consistent with the present invention;
Fig. 6 is a diagram of an apparatus for reading marks formed in a way consistent with the present invention.A device for implementing the method of marking corresponding to the present invention, shown in Fig. 1. The device has an emitter 10, which regulates the laser beam 12 is directed to the subject 14, which in this example is a bottle. Because subsurface marking in normal conditions should not be visible to the naked eye, but can become visible in polarized light, the bottle 14 elected such material as glass or plastic, transparent to electromagnetic radiation in the visible range of the electromagnetic spectrum. In addition, the emitter 10 is selected so that the material of the bottle 14 is essentially opaque to the laser beam generated by the emitter.In the specific example embodiment of the invention shown in Fig. 1, the emitter 10 includes a CO2-continuous laser radiation with high-frequency pumping, emitting the laser beam 12 with DJ beam 12 falls on the first reflecting surface 16, which directs the beam 12 through a beam expander 18 and the unifier of the beams 20 to the second reflecting surface 22. The second source of laser radiation, which represents the low-energy helium-neon laser 24, located next to the CO2laser 10 and emits secondary beam of visible laser radiation 26 with a wavelength of 632,9 nm. The secondary beam 26 hits one of the beams 20, which reflects it in the direction of the second reflecting surface 22 with the laser beam 12 CO2laser 10. The necessary property of unifier of rays 20 is that it transmits electromagnetic radiation with a wavelength of 10.6 microns, at the same time reflecting electromagnetic radiation with a wavelength of 632,9 nm. Thus, the beam 26 helium-neon (He-Ne) laser produces a visible component of the combined beam of 12.26 CO2laser and He-Ne-laser.Combined rays of 12.26 reflected from the second reflecting surface 22 to the third reflecting surface 28 and the third reflecting surface 28 is next to the fourth reflective surface 30. From the fourth reflecting surface 30 a combined beam of 12.26 again is reflected in the direction of the head 32, where the combined beam of 12.26 finally goes on the bottle 14. For O0 installed as a single piece with the cylinder 32 so that they can be adjusted in a vertical plane under the influence of the stepper motor 34 (not shown).In the head 32 of the consolidated beam of 12.26 CO2laser and He-Ne laser beam successively impinges on the two movable mirrors 36 and 38. The first mirror 36 is located so that it is inclined relative to the combined beam of 12.26, which falls on him, reflected from the fourth reflecting surface 30, and can be moved so that, reflecting the beam to move in a vertical plane. A second mirror 38 is inclined in a similar way, but to accept the combined beam of 12.26 reflected from the first mirror 36, and is moved in such a way as to reflect the beam of 12.26, move it in the horizontal plane. Thus, specialists, familiar with the known devices, it will be understood that the beam of 12.26 coming from the head 32 may be moved in any desired direction by means of the simultaneous movement of the first and second mirrors 36 and 38. To facilitate this movement of the two movable mirrors 36 and 38 are installed respectively on the first and second galvanometers 40 and 42. Clearly, there may be used any suitable means to control the mirrors 36 and 38, however, the approach adopted combines bylastname control.Coming out of the head 32, the combined beam of 12.26 concentrated, passed through the lens unit 44, which may include one or more lenses. The first lens 46 focuses the beam of 12.26 on the chosen point on the surface of the bottle 14. As is well known, the maximum power density of the beam of 12.26 inversely proportional to the square of the beam radius of 12.26 in its focus, which, in turn, is inversely proportional to the radius of the beam of 12.26 incident upon the focusing lens 46. Thus, for a beam of 12.26 electromagnetic radiation with wavelength and radius R, is incident on a lens with focal length f, the power density of E in focus in the first approximation is expressed by the formula
< / BR>where
P is the power generated by the laser.From this expression becomes obvious meaning and purpose of use of the beam expander 18, which, by increasing the beam radius R, serves to increase the power density E in focus. In addition, the lens 46 is typically short-focus lens having a focal length in the range of 70-80 mm, thus, the focus of the beam of 12.26 can be easily achieved power density equal to 6 kW/cm2.The second lens 48 may be placed in series with the focusing lens 46 to compensate for the curvature over which usesto flat for the incident beam. In addition, the need for such a lens is no longer, if the first element 46 has a variable focal length, and includes, for example, a lens with a flat floor. However, it should be noted that the application of one or more optical elements, it is particularly simple and elegant way to provide focusing of the beam of 12.26 on the surface of the object 14 regardless of any curvature.In the security interests of the two lasers 10 and 24 and, accordingly, their rays are enclosed in a security camera 52, as shown in Fig. 2, and the combined beam of 12.26 comes from the camera 52 only after passing through the lens unit 44. Access to the two lasers 10 and 24, and various optical elements located in the path of the respective rays of 12.26, through the door 54, equipped with a lock 56, preventing the work of CO2laser 10 and a He-Ne laser 24 when the door is open 54.Single-phase power source voltage 240V is supplied through the lock door 56 to an electrical junction box 58 located under the camera 52 and insulated from it to prevent electrical interference with the operation of the lasers 10 and 24. From the power distribution panel 58 of the electric power is fed to the CO2the laser 10 and HeNe laser 24, and hodaida to the stepper motor 34 and to the computer 62. Three rectifier and associated voltage regulators provide a constant voltage supply 12 V, 10 V and 28, respectively, at the He-Ne laser 24 to provide mechanism of the pump and the cylinder 32, where, in particular, the voltage of 28 V is used to power the first and second galvanometers 40 and 42, and a voltage of 10 V is applied to the galvanometer to implement a predetermined movement of the first and second mirrors 36 and 38. Thus, using the computer 62 to modulate the voltage To 10 V, on his program are the movements of the first and second mirrors 36 and 38.When using a laser beam 12 emitted from CO2laser 10, forms a light spot on the surface of the marked bottle 14. This spot can be moved across the surface of the bottle by moving one or both of the mirrors 36 and 38.It is well known that glass and some other substances that are transparent to electromagnetic radiation in the visible range of the electromagnetic spectrum that is opaque to electromagnetic radiation having a wavelength of 10.6 microns, and that CO2the laser generates radiation with this wavelength. While the applicant was found that with the use of CO2. Thus, while for most practical cases can be considered that the laser beam 12 is absorbed by the surface of marked object 14, the actual depth even 8.0 µm provides lacedemonia what should be understood under the term "opacity". Thus, to remove doubt in this context, the term "opacity" when used in connection with the marked substance means a substance capable of absorbing 95% of the energy of incident laser beam within a distance smaller than the distance from the surface, which is a subsurface mark.Despite the fact that 95% of laser energy is absorbed within the volume of interaction of the beam with the material impact of the beam on the marked material is not limited to this surface area. For example, thermal effect produced by the beam, can be felt outside of the volume of interaction of the beam with the material, because the glass has a significant coefficient of thermal conductivity. Also, the final map stresses may be beyond the scope of glass, which is directly affected by the laser beam, just as the voltage is distributed then the end of the cracks in the window glass. Thus, it should be borne in mind that in principle, the physical effects of learning can be observed in places remote from the location of the volume of interaction of the beam with the material.This situation is summarised by Mr arbitrary fraction of the energy of incident beam is transmitted material. The volume of interaction of the beam with the material (BIV) surrounds the heat conductive area CHZ whose boundary as volume BIV, can also be determined in an arbitrary limits. Outside the heat transfer area is tense area in which we have the voltage generated as a result of changes in the physical properties of matter due to thermal changes in the volume of BIV and throughout the CHZ or in part. Change the values of these voltages as a function of radial distance from the place of falling of the beam, indicated by curve 66, which shows that the peaks of voltage 68 may extend a small distance beyond the border between the volume of BIV and area CHZ.It was found that when using the CO2laser having a power density in the range of 6-10 kW/cm2you can create a mark in the glass at a depth of 40 to 50 μm for the depth to which it penetrates the laser radiation. This mark, which in cross section has a shape of convex lens typically has a depth (i.e., the size in the direction of the beam) 10.8 microns and a diameter of 125 μm and is the result of thermal interaction in the glass.In this context it should be noted that the possible types of interaction between laser radiation and the material of the object m the Ki of view of increasing power density is of the following categories:
1. Photochemical interaction, including photoinduction and photosensitivity.2. Thermal interaction, in which incident radiation is absorbed in the form of heat.3. Ionizing interaction, including non-thermal the photodecomposition of irradiated substance.The difference between the thresholds of these three interactions is clearly demonstrated by comparison of the typical power density of 10-3W/cm2required for the implementation of the photochemical interaction and power density of 10-12W/cm2typical ionizing interaction, such as photoespana and photodecomposition.Mark having the shape of the lens, not visible to the naked eye, but observed under a microscope in bright light and when placed between the overlapping polarizing filters, has clearly limited the bottom edge. This observation led to the assumption that the mark represents the border between the atoms of the glass receiving energy from the incident beam, sufficient to overcome the communication with the neighboring atoms, and atoms, have not received sufficient energy. As you can guess from the above model, the tense region extends beyond the lower the spine in the direction of the beam up to 60 μm, also invisible to the naked eye, but can become visible under polarized light.It was found that the mark having the shape of the lens and adjacent the tense region can be created only by the beam of CO2laser having a power density lying in a narrowly limited range. If the energy absorbed by the glass, too small, creates a thermal gradient sufficient to education observed the tense region. Conversely, if the absorbed energy is too large, the glass surface may melt, or the glass may crack along the line of stress peaks and flake off. This cracking of glass, known as "breakthrough", not only relieves tension in the remaining glass, and makes a mark as visible to the naked eye and detectable by surface analysis.In the described embodiment of the invention the laser beam 12 is moved along the surface of the bottle 14 with an average speed of 2 to 3 m/s for forming pattern using the alphanumeric images. But instead move the beam from one end of a straight line to another, it is preferable to carry out discrete scan that legitimate sine from zero, when the beam is at either of the extreme positions of the scanning of successive discrete increments and almost motionless, up to about 3 m/s at a point located between the two ends. Therefore, even if the power density of the beam is maintained at a constant level, a different point on the surface of the bottles are subjected to various impact energy beam. It was found that the power density range required to create the above-mentioned mark, significantly narrow, and mark having a shape of a lens, and the corresponding voltage is observed only at the points where the beam was almost motionless. As a result, when the polarized light voltage created by scanning the laser beam over the surface of the bottle, appear as a series of points. Thus, by controlling the movement of the mirrors 36 and 38 can be scanned by a laser beam on the surface of the bottle 14 and to form any desired character on the bottle in the form of a matrix of points.In an alternative embodiment of the invention similar to the matrix points may be created by scanning the beam over the surface of the bottle at a constant speed, periodically changing its power density between dei stresses. This type of change of power density may, for example, be obtained by imposing a sinusoidal ripple 70 on a rectangular laser pulse 72, as schematically shown in Fig. 4. Assuming that the threshold for the formation of the above-mentioned label is located on the power level represented by the dotted line 74, you can count on receiving point areas of stress in the glass, separated from each other by a distance corresponding to that which the laser beam passes between successive maximum values 76 profile power density 78.In both previous versions of the invention, it was proposed that a gradual increase in energy absorbed by the glass at points close to the actually generated label attached to the glass limited ability to firing. It shows the differences from the device in which the laser beam pulses, generating a number of marks at the points that are apart from each other at any distance. The property camobiga inherent in previous versions of the invention, provides for the marking of the subject, the strength of which does not deteriorate under the influence of labeling.Drawings of consecutive dots sozdavat in the glass and, thus in the plane of polarization of any light passing through it. This facilitates detection of the marks and allows you to create a "stitched" image, an example of which is shown in Fig. 5.In another embodiment of the invention, instead of creating a pattern of dots, the described device may provide a label that includes one or more continuous lines. In this case, the laser beam 12 can move along the surface of the marked object with a constant speed, while the power density of the beam is maintained at a constant level, slightly higher threshold of forming marks having the shapes of lenses, and a corresponding voltage.In yet another embodiment of the invention instead of scanning the laser beam 12 of the surface of the marked object 14, the beam may irradiate a mask. Using the premises of the mask before marked subject and when the mask one or more slots allocated part of the incident beam can fall on the subject and to form the label predetermined configuration.For observation labels established in accordance with any of the described embodiments of the invention, labeled pre the output beam. In the area of stress become visible in the form of bright areas against a dark background.An example of a device used for reading the marks formed in accordance with any of the described embodiments of the invention shown in Fig. 6 and includes a casing 100, similar to that used as the basis for hanger spotlight, which placed the lamp 102. The casing 100 has an upper working surface of the glass 104, and between this surface and the lamp 102 is placed Fresnel lens 106, capable direction of the main beam. Crossed linear polarizing filters 108 is placed between the working surface 104 and the Fresnel lens 106, and to maintain a safe operating temperature in the device casing 100 is equipped with a fan 110, similar to those used in computer systems, and the louvered opening 112 for access of air. To adjust the brightness of the lamp 102 can be used switch with dimmer.For observation of intense fields in a bulleted item 14 item is placed on the working surface 104 and examined under a 10x magnifier 114, equipped with appropriate filter 116. 1. The method of applying what about the radiation, this localized stress is formed so that it is invisible to the naked eye but can be observed in polarized light, characterized in that the material from which is made the subject of an essentially opaque, and the energy of the beam absorbed by the surface of the subject, sufficient to create a localized stresses in the object at points spaced from the said surface, without the formation of any appreciable change in the surface that will provide the problematic detection marked a potential infringer, and falsification and destruction of the label.2. The method according to p. 1, characterized in that the body of the subject contains a material having a thermal conductivity approximately equal to thermal conductivity of the glass.3. The method according to p. 1 or 2, characterized in that the marking is formed by localized stresses, represented by one or more numbers, letters or symbols, or combination thereof.4. The method according to any of the preceding paragraphs, characterized in that the beam of laser radiation concentrate for the formation of illuminated spots on the surface of the object, and the spot can be moved relative to the mark and, having a predefined configuration.5. The method according to p. 4, characterized in that spot is moved relative to the surface are marked so as to form an elongated area of localized stress, which when observed in polarized light has the appearance of a line.6. The method according to p. 4, characterized in that the spot moves relative to the marked object for forming a number of spaced apart regions of localized stress, which when observed in polarized light have the form of a set of points.7. The method according to p. 6, characterized in that a number of spaced apart regions of localized stress is formed by moving the spot with constant speed relative to the marked object and periodic changes in the power density of the beam.8. The method according to p. 6, characterized in that a number of spaced apart regions of localized stress form while maintaining the power density of the beam, essentially at a constant level and the change of time, during which the spot lights consistently placed on the points of the surface.9. The method according to p. 8, characterized in that the spot moves relative to marcerou is the action scene themes that spot is moved relative to the marked object with an average speed in the range of 2 to 3 m/s11. The method according to any of paragraphs.6 to 10, characterized in that the energy beam is absorbed by the consecutive points of the surface, smoothly change from one point to another.12. The method according to any of paragraphs.4 to 11, characterized in that the laser radiation has a power density in the spot up to 10 kW/cm2.13. The method according to any of paragraphs.1 to 3, characterized in that the beam of laser radiation is irradiated with a mask placed in front of a marked object, and the mask has one or more slits for forming a marking formed by localized stresses having a predefined configuration.14. The method according to any of the preceding paragraphs, characterized in that the beam of laser radiation generated with the help of CO2-laser.15. The method according to any of the preceding paragraphs, characterized in that the material of the marking object is transparent to electromagnetic radiation with wavelengths in the visible range.16. The method according to any of paragraphs.1 to 14, characterized in that the material of said marked localized voltage is controlled with the help of optical devices with the corresponding wavelength of the electromagnetic spectrum.17. The body of the subject, made of a material having a thermal conductivity approximately equal to thermal conductivity of glass, and marked in accordance with any of paragraphs.1 - 16 of way.18. The body of the subject, made of a material having a thermal conductivity approximately equal to thermal conductivity of glass, and having an area of localized stress at a distance a between the surface and without any detectable changes in the surface, and localized voltage pass from one edge of lenticular labels, essentially convex cross-section.19. The body under item 17 or 18, characterized in that it is transparent to electromagnetic radiation with wavelengths in the visible range.20. The body under item 18, characterized in that it is made of glass or plastic.21. Marked body of the subject under item 17 or 18, characterized in that it is opaque to electromagnetic radiation with wavelengths in the visible range, with localized voltage can only be observed using optical instruments with the corresponding wavelength in elektropitanie voltages, represents one or more numbers, letters, or symbols, or a combination of both.23. Body according to any one of paragraphs.17 to 22, characterized in that it is a container.
FIELD: printed matter of special format.
SUBSTANCE: multi-layered article comprises the layer sensitive to the laser radiation, marking member, e.g., diffraction and/or holographic structure, reflecting layer, and print formed in the second layer and/or in the layer sensitive to the laser radiation. The layer sensitive to the laser radiation has markers that are made by means of laser radiation and precisely positioned with respect to the marking member.
EFFECT: enhanced reliability of protection.
27 cl, 40 dwg
FIELD: protective members for visual controlling of authenticity of printing product such as security papers, banknotes, identification cards.
SUBSTANCE: protective member is formed as color layer applied to substrate and having color-free portions produced by exposing color layer to laser radiation for forming of image detected by visual control. Substrate surface is provided with relief, said image being formed on at least one side of relief after exposing to laser radiation falling at predetermined angle to relief surface. Protected printing product is equipped with protective member for visual controlling of paper authenticity.
EFFECT: increased extent of protecting printing products due to creation of protective member more complicated for counterfeit and using optical variable image.
7 cl, 5 dwg
FIELD: technological processes.
SUBSTANCE: digital array of data is created, which defines graphical configuration of partial plating, at that, using digital array, trajectory of tool motion is calculated, as well as control data for tool control, at that tool and single- or multi-layer film carcass are moved in relation to each other in accordance with tool motion trajectory. Tool that is controlled according to control data provides partial discrete de-metalation of metal layer by means of application of wipe-off mask for partial masking of single- or multi-layer film carcass. Foresaid mask is applied by spraying. Single- or multi-layer film carcass is further dried, provided with metal layer, and metal layer is partially removed by flushing method in area of wipe-off mask.
EFFECT: efficiency from production point of view, possibility to apply coating on different surfaces and exclusion of thermal or mechanical effect onto surface.
13 cl, 16 dwg
FIELD: technological processes.
SUBSTANCE: invention may be used in systems of laser marking and engraving in industry, for artistic applications, for authentication and personification of items and documents. Method for application of raster image consists in the fact that image of original is introduced into computer, image is transformed into raster array of numbers, working element coordinates are changed, working element is put in action, and dots are applied with its help onto surface of item. Working element used is represented by laser radiation. At the same time test image is previously downloaded into computer, and this image is applied onto surface of test sample, produced result is assessed, and laser radiation properties are accordingly adjusted in compliance with it. Multistage filtration of raster array of numbers is carried out, afterwards image of original is marked onto item.
EFFECT: high quality of applied image, increased resource of equipment, higher speed of image application, and also expansion of field of materials suitable for application of images.
FIELD: printing industry.
SUBSTANCE: invention is related to security paper, in particular to banknote, having individual mark, which is applied at least once on face and reverse side of security paper. At least one of individual identifiers applied on face and reverse side of security paper is applied onto security paper by contactless method. Besides application of individual identifiers on face and reverse side of security paper is carried out by means of single-sided treatment of security paper.
EFFECT: high degree of security paper protection, with minimum production costs.
32 cl, 16 dwg
FIELD: machine building.
SUBSTANCE: invention refers to method of laser labelling surface of metal or its alloy and can be implemented in machine building, jewellery industry and medicine. The method consists in preliminary plotting a calibration curve of dependence of depth of marking surface of a sample of specified metal or its alloy by means of effect of specific power of radiation incoming on surface. By means of a computer there is generated a protective digital code, where specific depth of marking and specific power of laser radiation correspond to each digit. A mark visible by a naked eye is applied on the marked surface of metal or its alloy by means of laser radiation transferred along marked surface; this mark corresponds to alpha-numeric or graphical information. A protective digital code in form of sequence of recesses invisible to a naked eye is applied on the produced surface visible to a naked eye; this code is marked by laser radiation of specific power chosen from the said calibrating curve.
EFFECT: high level of protection and simplified process.
8 cl, 5 dwg, 1 tbl, 1 ex
FIELD: physics, optics.
SUBSTANCE: device for transferring an image onto a wooden base has apparatus for receiving and/or creating an image. At least one source of a laser beam. Apparatus for moving the laser beam with rotation and/or translational movement of the laser beam relative the said wooden base or vice versa - for moving the wooden base relative the laser beam, as well as for focusing the laser beam onto the said base. At least one module for regulating radiation power of the laser beam. At least one module for controlling the said movement and focusing apparatus. Apparatus for converting information of the said image into an instruction for the said at least one regulation module and the said at least one control module. The said at least one regulation module regulates radiation power of the laser beam by directly changing pumping of the active substance and/or changing operation of the modulator located in the resonator of the source of the laser beam.
EFFECT: solution enables reproduction of images on a wooden base with an irregular shape with high accuracy and speed of processing, as well as high depth of transfer within the base.
22 cl, 2 dwg
FIELD: process engineering.
SUBSTANCE: proposed method may be used for making inscriptions and symbols on various materials, for examples, on light guides, light boards operated at high levels of illumination. Prior to applying coat of background material, contrast coat is applied that features minimum light reflection factor. Processed surface is divided along two coordinates into elementary sites to displace laser beam over said sites. All area of said sites is divided into area of sign outline and sign body area. On evaporating coats by laser radiation, the number of elementary sites is reduced to zero to form multistage sign profile comprising, at least, one step produced in contrast coat. Body sign area is kept unchanged.
EFFECT: higher readability and accuracy of signs, preservation of initial colours of materials.
3 cl, 3 dwg
SUBSTANCE: preliminary construction of calibration curve of dependence of etching depth of specimen surface of the specified metal or its alloy on parameters of incident laser radiation to surface is performed at monotonic increase in specific power of laser radiation from value of 0.1 J/cm2·s to the value at which molten drops are formed on etched surface. Then, spatial control of laser beam scanning on surface of metal or its alloy is performed at least as per one coordinate. Simultaneously with translational movement of laser beam there performed is its rotation with radius R. Radius R and angular rotation speed of laser beam is chosen considering the cut width and radius of laser beam.
EFFECT: improvement of the method.
5 cl, 3 dwg, 1 ex
FIELD: printing industry.
SUBSTANCE: invention relates to a method of manufacturing a protection property for the protective element, counterfeit-proof paper or data medium. The method of manufacturing a protection property for the protective element comprising a substrate which has at least one through hole and at least one marking in accurate register with this hole. The substrate, at least in the area of the manufactured marking is equipped with a marking substance modifiable by laser. During the same technological operation by exposure of laser radiation at high laser power at least one through hole is made in the substrate. By exposure of laser radiation at lower laser power at the marking area the marking substance is modified and thus at least one marking is created in accurate register with the through hole.
EFFECT: proposed protection property enhances the counterfeit protection level of the protective element.
23 cl, 5 dwg