Multilayer body with electrically controllable optically active systems of layers

• US 7,940,340 B2
• Filed: 07/04/2006
• Issued: 05/10/2011
• Est. Priority Date: 07/04/2005
• Status: Active Grant

• Current Assignee: Leonhard KURZ Stiftung & Company KG
• Original Assignee: Leonhard KURZ Stiftung & Company KG, PolyIC GmbH & Co. KG (Leonhard KURZ Stiftung & Company KG)
• Inventors: Ludwig, Klaus, Clemens, Wolfgang
• Primary Examiner(s): ROJAS, OMAR R
• Application Number:
  US11/994,571
• Publication Number:
  US 20080198278A1
• Time in Patent Office: 1,771 Days
• Field of Search: None
• US Class Current: 349/1
• CPC Class Codes: B42D 2033/26 Liquid-crystal material
• CPC Class Codes: B42D 2033/46 with electrical circuitry
• CPC Class Codes: B42D 25/29 Securities; Bank notes
• CPC Class Codes: B42D 25/328 Diffraction gratings; Holograms
• CPC Class Codes: B42D 25/364 Liquid crystals
• CPC Class Codes: G02F 1/0147 based on thermo-optic effects G02F1/132 takes precedence
• CPC Class Codes: G03H 1/0011 for security or authentication holograms on information-bearing cards B42D25/328; testing papers with holograms G07D7/0032
• CPC Class Codes: G03H 1/0244 Surface relief holograms replicating hologram without interference recording G03H1/0276
• CPC Class Codes: G03H 1/0256 having specific functional layer
• CPC Class Codes: G03H 2250/38 Liquid crystal
• CPC Class Codes: G03H 2260/12 Photopolymer

Abstract

A multilayer body (1) having an optically active first layer system (10) is described, in which case the first layer system (10) is an optically variable device (OVD), and the optical effect of the first layer system (10) can be influenced by an electrically controllable second layer system (20).

Claims

1. A multilayer body comprising:

an optically variable device (OVD) active first layer system having at least a diffractive optical effect; and

an electrically controllable second layer system for influencing the optical effect of the first layer system and arranged above the first layer system, the first layer system including a metallic reflective layer forming a lower electrode layer of the second layer system and exhibiting said at least diffractive optical effect;

wherein the first layer system comprises a relief structure and a metallic reflective lower electrode layer on the relief structure, which relief structure and lower electrode layer extend generally in a given direction, the relief structure comprising projections extending normal to the given direction and which projections alternate with diffraction gratings forming the diffractive optical effect in the given direction.

2. The multilayer body as claimed in claim 1 wherein the second layer system is arranged so that at least one of the optical characteristics of the second layer system including optical density, light scattering or color is arranged to be controllable electrically.

3. The multilayer body as claimed in claim 1 wherein the second layer system comprises an electrode layer in the form of a partial electrode layer with electrode areas arranged in the form of strips or a matrix.

4. The multilayer body as claimed in claim 1 wherein the first layer system comprises areas which reproduce at least one of an image or alphanumeric information.

5. The multilayer body as claimed in claim 1 wherein the optical effect of the second layer system is arranged to be reversibly controllable.

6. The multilayer body as claimed in claim 1 wherein the optical effect of the second layer system is arranged to be irreversibly controllable.

7. The multilayer body as claimed in claim 1 wherein the optical effect of the second layer system is arranged to be controlled in a bistable form.

8. The multilayer body as claimed in claim 1 wherein the first layer system comprises one of 1) a replication layer and an optical isolation layer or 2) a replication layer and a reflective layer, the replication layer in each case comprising a diffractive relief structure forming at least one of a diffraction grating, a hologram or other diffractive imaging arrangement for providing said diffractive optical effect.

9. The multilayer body as claimed in claim 1 wherein the first layer system is a thin-film layer system for producing color effects by electromagnetic radiation interference.

10. The multilayer body as claimed in claim 1 wherein the first layer system comprises a cholesteric liquid-crystal-layer and an absorption layer.

11. The multilayer body as claimed in claim 1 further including organic and/or inorganic drive electronics coupled to the second layer system.

12. The multilayer body as claimed in claim 1 further including at least one of one or more sensors, an RFID circuit , a display, a switch or a voltage source.

13. The multilayer body as claimed in claim 1 wherein the first and second layer systems are flexible.

14. The multilayer body as claimed in claim 1 wherein the first and second layer systems are flexible and supported on a flexible carrier film.

15. The multilayer body as claimed in claim 1 wherein the lower electrode layer of the second layer system extends in a given direction and is divided into different areas along that given direction, the different areas of the metallic reflective lower electrode layer comprising a planar electrode portion alternating with a diffractive grating electrode portion, the latter forming said optical diffractive optical effect.

16. The multilayer body as claimed in claim 1 wherein the first layer comprises the metallic reflective lower electrode layer extending in a given direction, the lower electrode layer being arranged in the given direction to alternately reflect light and to diffract light in a direction generally normal to the given direction.

17. The multilayer body as claimed in claim 1 wherein the first layer comprises a relief structure and a metallic reflective lower electrode layer on the relief structure, which relief structure and lower electrode layer extends in a given direction, the relief structure comprising projections extending normal to the given direction and which projections alternate with diffraction gratings forming the diffractive optical effect in the given direction, the reflective lower layer on the relief structure for reflecting and diffracting light in a direction generally normal to the given direction.

18. The multilayer body as claimed in claim 15 wherein the planar areas of the metallic reflective lower layer is formed as strips.

19. The multilayer body as claimed in claim 15 wherein the planar areas of the metallic reflective lower layer is formed as strips wherein alternate strips in the given direction are simultaneously connected to a voltage of opposite polarities.

20. A multilayer body comprising:

an optically variable device (OVD) active first layer system having at least a diffractive optical effect; and

an electrically controllable second layer system for influencing the optical effect of the first layer system and arranged above the first layer system, the first layer system including a metallic reflective layer forming a lower electrode layer of the second layer system and exhibiting said at least diffractive optical effect;

wherein the metallic reflective lower electrode layer comprises alternating projections and diffraction gratings extending in a given direction, the gratings forming said diffractive optical effect, the metallic reflective lower electrode layer on the projections being coplanar in a first plane and the diffraction gratings being coplanar in a second plane spaced from the first plane.

21. A multilayer body comprising:

an optically variable device (OVD) active first layer system having at least a diffractive optical effect; and

an electrically controllable second layer system for influencing the optical effect of the first layer system and arranged above the first layer system, the first layer system including a metallic reflective layer forming a lower electrode layer of the second layer system and exhibiting said at least diffractive optical effect;

wherein the lower electrode layer of the second layer system extends in a given direction and is divided into different areas along that direction, the different areas being electrically coupled to a voltage source for creating a field that runs with and extends in the given direction;

wherein the different areas of the metallic reflective lower electrode layer comprise alternating diffractive grating electrode portions, the diffractive grating areas of the metallic reflective lower layer being formed as strips wherein alternate strips in the given direction are simultaneously connected to a voltage of opposite polarities.