FORGE-PROOF DOCUMENT

Abstract

The present invention relates to a forge-proof document comprising: a front side, a back side, a first security feature comprising a perforation pattern which displays a first image information when viewed against a bright background, and a second security feature comprising a pattern which displays a second image information when light falling on the pattern is reflected, wherein the first and the second image information to be displayed on the forge-proof document correspond with each other, wherein the front side comprises the second security feature, wherein the back side comprises the second security feature, and wherein the second image information of the back side is the mirrored image information of the second image information of the front side.

Claims

1. A forge-proof document comprising: a front side; a back side; a first security feature comprising a perforation pattern which displays a first image information when viewed against a bright background; and a second security feature on each of the front and back sides, the second security feature of each side comprising a pattern which displays a second image information; wherein the second image information on each of the front and back sides and the first image information correspond with each other; and wherein the second image information of the back side is mirrored image information of the second image information of the front side.

2. The forge-proof document according to claim 1, herein: the second security feature on the front side comprises at least one of an engraved pattern, an inkjet printed pattern, or a laser printed pattern; and the second security feature on the back side comprises at least one of an engraved pattern, an inkjet printed pattern, or a laser printed pattern.

3. (canceled)

4. The forge-proof document according to claim 1, wherein the first image information and the second image information on the back side coincide.

5. (canceled)

6. The forge-proof document according to claim 4, wherein the second image information on the front side coincides with the first image information and the second image information on the back side.

7. The forge-proof document according to claim 1, wherein the second image information on the front side comprises a greater or smaller size on the document than the second image information of on the back side.

8. The forge-proof document according to claim 1, wherein: the pattern of the second security feature on the front side is made by a first printing technique; and the pattern of the second security feature on the back side is made by a second printing technique

9. The forge-proof document according to claim 8, wherein: the first and second printing techniques differ from each other; the first printing technique comprises laser engraving, inkjet printing, or laser printing; and the second printing technique comprises laser engraving, inkjet printing, or laser printing.

10. The forge-proof document according to claim 1, wherein at least some perforations forming the perforation pattern extend over only a part of a thickness of the document, and a thickness of a remaining part of the document at a position of each of the at least some perforations is modulated in accordance with the first image information.

11. The forge-proof document according to claim 1, wherein at least some perforations forming the perforation pattern extend at an angle differing from 90 degrees relative to a main plane of the document, and the angles of the at least some perforations is modulated to obtain a grey-value modulation of the first image information.

12. (canceled)

13. The forge-proof document according to claim 1, wherein material is arranged in at least some perforations of the perforation pattern of the first security feature, and the material is at least one of an ink which lights up under UV light or a vapour-deposited metal layer.

14. The forge-proof document according to claim 1, comprising differently colored material layers, wherein for each perforation of the perforation pattern, a color is visible depending on the depth of the respective perforation.

15. (canceled)

16. The forge-proof document according to claim 1, wherein at least one of a density of perforations or a diameter of perforations for at least some perforations forming the perforation pattern is modulated in order to generate the first image information.

17. The forge-proof document according to claim 1, wherein the document is manufactured from plastic laminate and a core layer of the plastic laminate has a color differing from at least another layer of the plastic laminate.

18. The forge-proof document according to claim 7, wherein a size of the second image information on the back side and a size of the first image information are the same.

19. The forge-proof document according to claim 1, wherein the perforation pattern of the first security feature is configured to present an image which differs by angle of view.

20. The forge-proof document according to claim 1, wherein a cross-section of at least one perforation of the perforation pattern in a transverse plane is non-circular.

21. The forge-proof document according to claim 9, wherein the first printing technique comprises laser engraving and the second printing technique comprises inkjet printing or laser printing.

22. A forge-proof document comprising: a first side; a second side; a first security feature on the first side, the first security feature comprising a pattern that displays first image information; and a second security feature on the second side, the second security feature comprising a pattern that displays second image information; wherein the second image information is mirrored image information of the first image information.

23. The forge-proof document according to claim 22, wherein the pattern of the first or second security feature comprises a perforation pattern which displays the first or second image information, respectively, when viewed against a bright background.

24. A method of forming a forge-proof document, the method comprising: forming a first security feature on a first side of the document, the first security feature comprising a pattern that displays first image information; and forming a second security feature on a second side of the document, the second security feature comprising a pattern that displays second image information; wherein the second image information is mirrored image information of the first image information.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0120] FIG. 1 shows a second security feature of a front side of an inventive forge-proof document;

[0121] FIG. 2 shows a second security feature of a back side of the inventive forge-proof document;

[0122] FIG. 3 shows a first and second security feature of a front side of the inventive forge-proof document positioned such that light can shine through;

[0123] FIG. 4 shows a first and second security feature of a back side of the inventive forge-proof document positioned such that light can shine through;

[0124] FIG. 5 shows a schematic perspective view of a device for manufacturing a forge-proof document according to the present invention;

[0125] FIG. 6 shows a detail view of a perforation pattern such as illustrated in FIG. 5;

[0126] FIG. 7 shows a schematic perspective view of a passport according to the present invention;

[0127] FIG. 8 shows a view of a bank note provided with a pattern according to the present invention;

[0128] FIG. 9 shows a postage stamp provided with a perforation pattern according to another embodiment of the present invention;

[0129] FIG. 10 shows a cross-sectional view of an embodiment of a forge-proof document according to the present invention;

[0130] FIG. 11 shows a cross-sectional view of an embodiment of a forge-proof document according to the present invention;

[0131] FIG. 12 shows a cross-sectional view of an embodiment of a forge-proof document according to the present invention;

[0132] FIG. 13 shows a cross-sectional view of an embodiment of a forge-proof document according to the present invention;

[0133] FIG. 14 shows a cross-sectional view of an embodiment of a forge-proof document according to the present invention;

[0134] FIG. 15 shows a schematic perspective detail view of an embodiment of the invention;

[0135] FIG. 16 shows a schematic perspective detail view of an embodiment of the invention;

[0136] FIG. 17 shows a cross-sectional view of an embodiment of the invention, which also serves to elucidate the method used therein; and

[0137] FIG. 18 shows a cross-sectional view of an embodiment of the present invention.

DESCRIPTION OF THE EMBODIMENTS

[0138] In the following several embodiments of the present invention are explained based on the drawings. It is noticed that the drawings show each a specific embodiment as explained below and further alternative modifications as specified in the description are at least in part not illustrated. However, it is explicitly pointed out that, in particular, the features shown in FIGS. 5 to 18 can be combined with a forge-proof document described in FIGS. 1 to 4.

[0139] Further, the same reference signs used in the Figures denote the same components.

[0140] In FIG. 1 a second security feature 3 of a front side F of an inventive forge-proof document 1 is shown, wherein FIG. 2 shows a second security feature 3 of a back side B of the inventive forge-proof document 1.

[0141] Further, FIG. 3 shows a first and second security feature 2, 3 of the front side F of the inventive forge-proof document 1 positioned such that light can shine through, wherein FIG. 4 shows a first and second security feature 2, 3 of a back side B of the inventive forge-proof document 1 also positioned such that light can shine through.

[0142] For the sake of ease and brevity in the following, FIGS. 1 to 4 are described together.

[0143] FIGS. 1 to 4 show a forge-proof document 1 having a front side F (FIGS. 1 and 3) and a back side B (FIGS. 2 and 4).

[0144] The forge-proof document 1 has a first security feature 2 comprising a perforation pattern 4 which displays a first image information when viewed against a bright background, and a second security feature 3 comprising an engraved pattern 5 which displays a second image information when light falling on the engraved pattern 5 is reflected.

[0145] It is noted that the first and second security feature 2, 3 represent an image of a person and a passport photograph, respectively.

[0146] It is also noticed that instead of an engraved pattern it is possible to use an inkjet printed pattern as the second security feature or to use a laser printed pattern as the second security feature.

[0147] Further, as can be easily seen from FIGS. 1 to 4, the first and the second image information 4, 5 to be displayed on the forge-proof document 1 correspond with each other.

[0148] Moreover, the front side F and the back side B comprise the second security feature 3, wherein the second image information 5 of the back side B is the mirrored image information of the second image information 5 of the front side F.

[0149] In other words, all the observable first and second image information 4, 5 on the back side B is the horizontally mirrored image information of the observable first and second image information 4, 5 on the front side F (cf. FIGS. 3 and 4).

[0150] Further, on the front side F, the second image information 5 represented by the second security feature 3 corresponds to the second image information 5 on the back side B.

[0151] Moreover, on the back side B, the second image information 5 represented by the second security feature 3 is identical to the first image information 4 represented by the first security feature 2 (cf. FIG. 4).

[0152] And on the back side B, the first and second image information 4, 5 of the corresponding security features 2, 3 coincide as can be seen by comparing FIGS. 2 and 4.

[0153] As also can be seen from the FIGS. 1 to 4, the second image information 5 of the front side F comprises a greater size on document 1 than the second image information 5 of the back side B, wherein the size of the second image information 5 on the back side B and the size of the first image information 4 are identical (cf. FIG. 4).

[0154] Summarizing the above. As shown in FIGS. 1 to 4 the forge-proof document's front side F comprises the second security feature 3 having an engraved pattern 5 which displays a second image information when light falling on the engraved pattern is reflected.

[0155] The back side B comprises the second security feature 3 having an engraved pattern 5 which displays a second image information when light falling on the engraved pattern 5 is reflected.

[0156] Further, the forge-proof document 1 comprises—as already mentioned—the first security feature 2 having a perforation pattern which displays a first image information 4 when viewed against a bright background, and the second image information 5 of the front and back sides F, B corresponds to the first image information 4.

[0157] Even further, the second image information 5 of the back side B is the mirror image information of the second image information 5 of the front side F.

[0158] Referring to all FIGS. 1 to 4, the mentioned figures show that the first security feature 2 in the form of a perforation pattern displays grey tones when viewed against a bright background.

[0159] The forge-proof document 1 is manufactured from a material which transmits light to a limited extent, wherein some of the perforations forming part of the perforation pattern extend over only a part of the thickness of the document 1 at the position of the perforation.

[0160] Thus, the thickness of the remaining part of the document 1 at the position of the perforation is modulated in accordance with the image to be displayed.

[0161] To achieve different grey tones, the density and/or the diameter of the perforations of the first security feature 2 is modulated in order to generate the first image information. An embodiment explaining to achieve these different grey tones will be explained below.

[0162] As explained above the first security feature 2 comprises a perforation pattern 4 which displays a first image information when viewed against a bright background, and the second security feature 3 comprises an engraved pattern 5 which displays a second image information when light falling on the engraved pattern 5 is reflected.

[0163] However, it is also possible that the front side F of the forge-proof document 1 comprises the second security feature 3 having a pattern of a first printing technique, and the back side B comprises the second security feature 3 having a pattern of a second printing technique.

[0164] In such an embodiment, the first and second printing technique differ from each other. This means that the first and second printing techniques comprise laser engraving, inkjet printing or laser printing, wherein in this special embodiment, the first printing technique comprises laser engraving and the second printing technique comprises inkjet printing or laser printing. In other words, the pattern of the second security feature displays a second image information when light falling on the pattern is reflected.

[0165] Further, in this special embodiment with two different printing techniques for the second security feature 3 on the front side F and on the back side B, the second image information 5 made by the first printing technique is applied on the front side F and the second image information 5 made by the second printing technique is applied on the back side B.

[0166] Further, the second image information 5 corresponds to the first image information 4, wherein the second image information 5 of the back side B is the mirror image information of the second image information 5 of the front side F.

[0167] Now reference is made to FIGS. 5 to 9.

[0168] Before discussion of the technique shown in FIGS. 5 to 9, it is pointed out that in the present technique, the making of brightness tones, as in the graphic art, is possible by means of perforations which are applied according to a fixed grid, wherein the size of the perforations is a measure for the intensity and that it is also possible to reproduce brightness tones by making use of perforation holes of equal dimensions, wherein the density of these dimensions is a measure for the intensity. Both options can in principle also be combined.

[0169] It is pointed out here that in the graphic art the first option is equivalent to the manner in which black and white photographs are reproduced in newspapers and that an example of the second technique can be found in the series of Netherlands postage stamps in which the likeness of Her Majesty the Queen is represented by dots of varying density.

[0170] Shown in FIG. 5 is a video camera 10 which is directed at a passport photograph 11. Video camera 10 records the image of passport photograph 11, converts it into an electronic form and feeds the thus obtained signal to a computer 12 in which it is stored.

[0171] The device shown in FIG. 5 further comprises a laser beam generating means 13 which is controlled by computer 12. This control relates not only to the intensity and focusing of the laser beam 14 transmitted by laser device 13, but also to the direction in which laser beam 14 is transmitted. It is possible to vary this direction in two planes to apply a perforation pattern 16 and a first security information in a document 15.

[0172] It is pointed out here that such laser devices are known in the prior art; in order to change the laser light beam, use is herein made of mirror systems not otherwise shown in FIG. 5. It is also possible to have laser device 13 stand still and to cause a carrier on which document 15 is placed to move. It is also possible to cause the carrier to move in one direction and the laser beam in the other direction; the choice between the various possibilities depends on the technology used. Essential is however that perforation pattern 16 and a first security information comprise perforation holes of differing diameter, wherein the diameter is a function of the brightness to be represented in the image. Perforation holes of differing density can be made by causing the laser beam to generate more or fewer holes locally.

[0173] This is illustrated more clearly in FIG. 6, which shows a detail of perforation pattern 16. Herein can be seen that in the present embodiment the perforation pattern is formed by perforation holes 17 which are ordered in a regular grid, for instance a rectangular grid.

[0174] The dimension of the holes is herein a measure for the brightness of the image represented by perforation pattern 16, in the present case the passport photograph 11. It is noted here that the dimensions of the perforation holes can be adjusted continuously, thus, in principle, in analog manner; by processing with a digital computer, a finite, yet large, number of stages is however obtained. Tests have demonstrated that it is nevertheless possible to obtain a representation of an image which forms an adequate rendering of the relevant image and can be easily compared therewith. It will be apparent that in this manner a good authenticity feature is obtained which is difficult to copy.

[0175] Shown in FIG. 7 is a passport 18 in which the photograph 11 is fixed, for instance by means of glue, tubular rivets or other manner of attachment. On the same page, adjacently thereof, a perforation pattern 16 representing the relevant image is applied. A good comparison can be made by holding up the relevant page of the passport to the light. It is otherwise also possible to apply the perforation pattern on another page of the passport, provided a quick visual comparison is possible. This makes forgery more difficult since at least two different pages must be forged for this purpose. It is also possible to apply the image enlarged, reduced in size or modified in other manner.

[0176] FIG. 8 shows a banknote 19 which is provided with a perforation pattern 20, in the present case in the form of an owl. This perforation pattern is not related to another image arranged on the banknote but forms exclusively a security feature per se; it is possible to provide banknotes with such a security feature. It is again pointed out that the difference with the prior art lies in the fact that the image 20 represents different brightness tones, for instance grey tones. Use is otherwise made herein of a free grid, wherein the dimensions of the perforations are the same and the density of the perforations varies in order to represent the grey tones. The same applies for the postage stamp 21 shown in FIG. 9 which is provided with a perforation pattern 22 in the form of a likeness of Her Majesty the Queen; both forms are herein combined, i.e., a varying grid, wherein the dimensions of the perforations also differ.

[0177] Again, it is pointed out that the description of FIGS. 5 to 9 can be applied for the first security feature 2 shown in FIGS. 1 to 4.

[0178] Thus, some or all mentioned features of FIGS. 5 to 9 can be incorporated in the embodiment shown in FIGS. 1 to 4.

[0179] Now reference is made to FIGS. 10 to 17.

[0180] FIG. 10 shows a cross-section of a forge-proof document 1. Document 1 is manufactured from plastic but can likewise be manufactured from another material, such as paper or textile, and it can also be manufactured from laminated material, wherein a combination of diverse material types is made.

[0181] This document 1 is provided with perforations. In FIG. 10, the perforations 32 have been arranged. In this embodiment of the present invention, perforations 32 do not extend through the whole thickness of document 1 but leave a part 33 of the document 1 intact.

[0182] The remaining parts 33 of the diverse perforations are herein of differing thickness. They therefore transmit light to a greater or lesser extent and, when the document is held against the light, an image comprising grey tones will result subject to the thickness of the remaining part 33 and the depth of perforation 32.

[0183] According to an embodiment as shown in FIG. 11, the perforations are arranged obliquely, i.e., at an angle differing from 90° relative to the main plane of the document. It is herein possible to obtain a modulation of the grey tones by varying the relevant angle. This is elucidated with dotted lines in FIG. 11.

[0184] It is further possible as shown in FIG. 12 to modulate the width, i.e., the diameter of holes 34. It is of course possible here to combine both forms of modulation. It is moreover possible to combine one of the two modulation forms or both of them with modulation of the density of the perforations. It is of course possible to assign determined properties to such a combination of modulation methods. An example hereof is shown in FIG. 13.

[0185] When the document is viewed straight on, as indicated with dotted lines in FIG. 12, a similar grey tone is herein displayed for each of the perforations.

[0186] This grey tone can be modulated by varying the density or by varying the size of the perforations. It is herein possible according to the invention to generate an image.

[0187] Owing to the fact that both perforations 34 are arranged obliquely, it is possible to provide these perforations with extra information, for instance by arranging them in the form of a letter or a logo. This is of course only visible when the image is viewed at a determined angle.

[0188] In the embodiment shown in FIG. 14, a perforation in the form of a cone or in the form of a truncated cone is obtained in both cases. Modulation of the visible grey tone can herein be obtained by varying the “depth” of the cone or its apex angle. This thus forms a combination of depth of hole modulation and diameter of hole modulation. Perforation 40 is thus, for instance, continuous, while perforation 41 is blind.

[0189] It is further possible, as shown in FIG. 15, to arrange a perforation in a form differing from a circle, for instance a rectangle 36. The rectangular perforation can be difficult to obtain with mechanical means, so that a laser is necessary for this purpose. A laser beam can, after all, be controlled such that it causes a perforation with such a contour, provided the focusing is sufficiently fine. It will be apparent that other shapes are possible, such as triangles, squares, ovals and so on.

[0190] FIG. 16 shows a configuration wherein this document is provided with layer 37 provided with ink. This layer is not particularly noticeable when the perforation is arranged with a laser; this layer is also removed by the laser. When an attempt is made to provide such a document with a perforation by means of mechanical means, for instance drilling, the ink will smear, which is clearly visible. Such a configuration can also be applied to laminated cards, the inner layer of which has a colour, for instance white, which differs from the colours of the other layers.

[0191] FIG. 17 shows how it is possible, using the same laser light source 38, to provide the same document 1 in different positions with a straight perforation 35 and subsequently with an oblique perforation 34. It is of course essential herein that the laser light beam 39 leaving laser source 38 can be deflected sufficiently. In addition, accurate stops and the like are necessary for the required precision in the positioning of document 1 in the different positions. It will be apparent that it is possible to perforate the document from more than two positions.

[0192] Finally, FIG. 18 shows an embodiment wherein laser light source 38 is placed relatively close to document 1, so that as a result of the angular deviation there result perforations which extend at a different angle. It will further be apparent that it is possible within the scope of the present invention to vary in countless ways from the shown embodiments.

[0193] Again, it is pointed out that the description of FIGS. 10 to 18 can be applied for the first security feature 2 shown in FIGS. 1 to 4.

[0194] Thus, some or all mentioned features of FIGS. 10 to 18 can be incorporated in the embodiment shown in FIGS. 1 to 4.