OPTICAL SYSTEM DEMONSTRATING IMPROVED RESISTANCE TO OPTICALLY DEGRADING EXTERNAL EFFECTS

• US 20100308571A1
• Filed: 06/22/2010
• Published: 12/09/2010
• Est. Priority Date: 11/21/2003
• Status: Active Grant

• Current Assignee: Visual Physics LLC (Crane Company)
• Original Assignee: Visual Physics LLC (Crane Company)
• Inventors: Cape, Samuel M., Hurt, Mark J., Steenblik, Richard A., Jordan, Gregory R.
• Granted Patent: US 8,867,134 B2
• Time in Patent Office: Days
• US Class Current: 283/72
• CPC Class Codes: B42D 15/0073 characterised by shape or material of the sheets
• CPC Class Codes: B42D 2035/20 Optical effects
• CPC Class Codes: B42D 2035/44 Miniaturised markings
• CPC Class Codes: B42D 25/21 for multiple purposes
• CPC Class Codes: B42D 25/29 Securities; Bank notes
• CPC Class Codes: B42D 25/324 Reliefs
• CPC Class Codes: B42D 25/355 Security threads
• CPC Class Codes: D21H 21/44 Latent security elements, i.e. detectable or becoming apparent only by use of special verification or tampering devices or methods
• CPC Class Codes: G02B 3/0031 Replication or moulding, e.g. hot embossing, UV-casting, injection moulding
• CPC Class Codes: G02B 3/0056 arranged along two different directions in a plane, e.g. honeycomb arrangement of lenses G02B3/0043 takes precedence; miniaturised objectives for electronic devices employing wafer level optics G02B13/0085
• CPC Class Codes: G02B 30/27 involving lenticular arrays

Abstract

A system for projecting one or more synthetic optical images, which demonstrates improved resistance to optically degrading external effects, is provided. The inventive system serves to lock the focal length of the focusing elements in place. In other words, no other transparent materials or layers brought into contact with the inventive system will serve to materially alter the focal length or the optical acuity of synthetic images formed by the system.

Claims

1. A system for projecting one or more synthetic optical images, which demonstrates improved resistance to optically degrading external effects, and which comprises:

(a) one or more arrangements of image icons; and

(b) one or more partially or totally embedded arrangements of image icon focusing elements,

wherein the one or more arrangements of image icon focusing elements is disposed relative to the one or more arrangements of image icons such that at least a portion of the image icon focusing elements forms at least one synthetic image of at least a portion of the image icons.

2. The system of claim 1, wherein the image icon focusing elements are refractive focusing elements having a focal length, the system having a refractive index from an outer surface to refracting interfaces that is varied between a first and a second refractive index, the first refractive index being substantially or measurably different than the second refractive index.

3. The system of claim 2, wherein the difference between the first refractive index and the second refractive index causes a change of at least about 0.1 micron in the focal length of the focusing elements.

4. The system of claim 1, which comprises:

(a) an array of image icons;

(b) an array of image icon focusing elements formed from a first material having a refractive index (n1); and

(c) a second material having a different refractive index (n2) that fills interstitial spaces between and/or covers the focusing elements, a distinct interface being formed between the first and second materials.

5. The system of claim 4, wherein the second material embeds the array of image icon focusing elements.

6. The system of claim 5, wherein the second material forms an outer boundary or layer of the array of image icons, thereby also embedding the array of image icons.

7. The system of claim 1, which comprises:

(a) an array of image icons; and

(b) an array of image icon focusing elements formed from a first material having a refractive index (n1) and a second material having a different refractive index (n2), the second material diffusing into the first material thereby forming a gradient interface with the first material.

8. The system of claim 4 or 7, wherein the focusing elements are selected from the group of converging lenses and diverging lenses.

9. The system of claim 4 or 7, wherein the first material has a refractive index ranging from about 1.5 to about 1.8.

10. The system of claim 9, wherein the first material is selected from the group of acrylated urethanes, epoxy acrylates and acrylic oligomers.

11. The system of claim 4 or 7, wherein the second material has a refractive index ranging from about 1.35 to about 1.49.

12. The system of claim 11, wherein the second material is selected from the group of urethane acrylates and acrylate monomers.

13. The system of claim 9, wherein the first material has a refractive index ranging from about 1.549 to about 1.56.

14. The system of claim 13, wherein the first material is a modified epoxy acrylate.

15. The system of claim 11, wherein the second material has a refractive index ranging from about 1.44 to about 1.45.

16. The system of claim 15, wherein the second material is isodecyl acrylate.

17. The system of claim 4 or 7, wherein the second material is a transparent or translucent adhesive.

18. The system of claim 1, wherein the one or more partially or totally embedded arrangements of image icon focusing elements includes image icon focusing elements selected from the group of cylindrical lenses, non-cylindrical lenses, and combinations thereof.

19. The system of claim 18, wherein the one or more partially or totally embedded arrangements of image icon focusing elements includes cylindrical lenses.

20. The system of claim 18, wherein the one or more partially or totally embedded arrangements of image icon focusing elements includes non-cylindrical lenses.

21. The system of claim 18, wherein the lenses have spheric or aspheric surfaces.

22. The system of claim 18, wherein the lenses have widths or base diameters of less than or equal to about 1 millimeter.

23. The system of claim 22, wherein the lenses have widths or base diameters ranging from about 200 to about 500 microns.

24. The system of claim 23, wherein the lenses have widths or base diameters ranging from about 50 to about 199 microns.

25. The system of claim 24, wherein the lenses have widths or base diameters of less than about 50 microns.

26. The system of claim 1 or 18, wherein the system has a thickness of less than or equal to about 1 millimeter.

27. The system of claim 26, wherein the system has a thickness ranging from about 200 to about 500 microns.

28. The system of claim 27, wherein the system has a thickness ranging from about 50 to about 199 microns.

29. The system of claim 28, wherein the system has a thickness of less than about 50 microns.

30. A sheet material made from the system for projecting one or more synthetic optical images of claim 1.

31. A sheet material made from the system for projecting one or more synthetic optical images of claim 4 or 7.

32. The sheet material of claim 30, which is selected from the group of substrates for subsequent printing or personalization, sheet materials for security documents, and base platforms for identification cards and security documents.

33. The sheet material of claim 32, which is a sheet material for security documents.

34. The sheet material of claim 32, which is a base platform for identification cards and security documents.

35. The sheet material of claim 30 or 32, wherein the sheet material has a thickness of less than or equal to about 1 millimeter.

36. The sheet material of claim 35, wherein the sheet material has a thickness of from about 200 to about 500 microns.

37. The sheet material of claim 36, wherein the sheet material has a thickness of from about 50 to about 199 microns.

38. The sheet material of claim 37, wherein the sheet material has a thickness of less than about 50 microns.

39. A base platform made from the system for projecting one or more synthetic optical images of claim 4 or 7.

40. The base platform of claim 39, wherein the first material has a refractive index ranging from about 1.35 to about 1.49.

41. The base platform of claim 40, wherein the first material is selected from the group of urethane acrylics and acrylic monomers,

42. The base platform of claim 39, wherein the second material has a refractive index ranging from about 1.5 to about 1.8.

43. The base platform of claim 42, wherein the second material is selected from the group of epoxy acrylates, polyester oligomers, poly(aromatic carbonates), and poly(aliphatic carbonates).

44. The base platform of claim 40, wherein the first material has a refractive index ranging from about 1.449 to about 1.46.

45. The base platform of claim 44, wherein the first material is tri(propylene glycol) diacrylate,

46. The base platform of claim 42, wherein the second material has a refractive index ranging from about 1.584 to about 1.685.

47. The base platform of claim 46, wherein the second material is polycarbonate

48. The base platform of claim 39, wherein the second material is a transparent or translucent adhesive.

49. A security device made from the system for projecting one or more synthetic optical images of claim 1.

50. A security device made from the system for projecting one or more synthetic optical images of claim 4 or 7.

51. The security device of claim 49, which is selected from the group of security strips, threads, patches, and overlays, for mounting on a surface of, or at least partially embedding within, a sheet material.

52. The security device of claim 49 or 51, wherein the security device has a thickness of less than about 50 microns.

53. The security device of claim 52, wherein the security device has a thickness of less than about 45 microns.

54. The security device of claim 53, wherein the security device has a thickness of from about 10 to about 40 microns.

55. A sheet material having opposing surfaces and comprising at least one security device of claim 51 mounted on a surface of, or at least partially embedded within, the sheet material.

56. A document made from the sheet material of claim 55.

57. The document of claim 56, which is selected from the group of banknotes, passports, identification cards, credit cards, and labels.

58. The document of claim 57, which comprises a banknote.