Film element

Patent metadata

Field	Value
Publication number	US-9983335-B2
Application number	US-201414559211-A
Country	US
Kind code	B2
Filing date	Dec 3, 2014
Priority date	Jan 17, 2008
Publication date	May 29, 2018
Grant date	May 29, 2018

Abstract

The invention concerns a film element having a replication layer ( 43 ), wherein an optically active surface structure ( 27 ) is shaped in a first surface of the replication layer. The surface structure is formed in at least a first region of the film element ( 35 ) by a first diffractive surface relief ( 46 ) comprising a plurality of successive elements following a first envelope curve ( 47 ), wherein the elements respectively comprise an element surface ( 48 ) arranged substantially parallel to a base surface and at least one flank adjoining the adjacent element surface or surfaces, the element surfaces ( 48 ) of adjacent elements are spaced in a direction perpendicular to the base plane, with a first optical spacing or a plurality of the first optical spacing, wherein the first optical spacing is between 150 nm and 800 nm, preferably between 150 nm and 400 nm. The first envelope curve ( 47 ) has a spatial frequency of between 100 L/mm and 2000 L/mm and an optical depth of more than 450 nm and the relief shape and the spatial frequency of the envelope curve ( 47 ) are so selected that the incident light is diffracted into one or more first directions to represent a first item of information, the color value of which is further determined by the first optical spacing.

First claim

The invention claimed is:

1. A film element having a replication layer with a first surface and a second surface opposite the first surface, wherein an optically active surface structure is shaped in the first surface of the replication layer and the second surface of the replication layer defines a base plane, and
wherein the surface structure is formed in at least a first region of the film element by a first diffractive surface relief comprising a plurality of successive reflection elements following a first envelope curve, wherein the reflection elements respectively comprise a reflective element surface arranged substantially parallel to a base surface and at least one flank adjoining the adjacent element surface or surfaces, and
wherein the base surface is oriented at an angle of inclination of at least 5° with respect to the base plane, and
wherein the element surfaces of adjacent elements are spaced in a direction perpendicular to the base surface such that the element surfaces of at least three adjacent elements each have a different height with respect to each other and with respect to the base surface with a first optical spacing or a plurality of the first optical spacing, wherein the first optical spacing is between 150 nm and 800 nm, and
wherein the first envelope curve has a spatial frequency of between 100 L/mm and 2000 L/mm and an optical depth at at least one location of more than 450 nm, wherein the optical depth is defined by the geometric difference between a minimum and a maximum perpendicular distance of the envelope curve with respect to the base surface, and the relief shape and the spatial frequency of the envelope curve are so selected that the incident light is diffracted into one or more first directions to represent a first item of information, the color value of which is further determined by the first optical spacing, and
wherein, in at least one second region, the surface structure is formed by a second surface relief, the second surface relief being an optically active surface relief which is not substructured by element surfaces such that the second surface relief differs from the first surface relief and which represents a second item of information, and
wherein the second surface relief is a diffractive surface relief comprising at least one of a diffraction grating or a hologram.

2. A film element as set forth in claim 1 , wherein the first region has a smallest dimension of more than 50 μm.

3. A film element as set forth in claim 1 , wherein the first region is shaped in the form of one or more symbols or a portrait.

4. A film element as set forth in claim 1 , wherein the at least one second region adjoins the first region or regions.

5. A film element as set forth in claim 1 , wherein the first region entirely encloses the second region or the second region entirely encloses the first region.

6. A film element as set forth in claim 1 , wherein the first envelope curve is a one-dimensional grating and wherein the second region is formed by two or more second subregions which are of a strip-shaped configuration of a width of less than 300 μm, and wherein the second subregions are spaced from each other in accordance with a periodic second raster of a raster width of less than 300 μm and at least region-wise a second subregion is arranged between two first subregions.

7. A film element as set forth in claim 1 , wherein the first and/or the second region is shaped in pattern form in the form of a third and fourth item of information respectively.

8. A film element as set forth in claim 7 , wherein the first and the second item of information and/or the third and the fourth item of information represent mutually supplemental items of information.

9. A film element as set forth in claim 1 , wherein the first envelope curve has an asymmetric relief profile.

10. A film element as set forth in claim 1 , wherein the first envelope curve is substructured such that the first item of information is generated substantially by diffraction of light in the first or minus-first diffraction order.

11. A film element as set forth in claim 1 , wherein the first envelope curve is substructured such that a color/tilt optical effect or a change in the color impression of the first item of information is generated upon rotation of the film element.

12. A film element having a replication layer with a first surface and a second surface opposite the first surface, wherein an optically active surface structure is shaped in the first surface of the replication layer and the second surface of the replication layer defines a base plane, and
wherein the surface structure is formed in at least a first region of the film element by a first diffractive surface relief comprising a plurality of successive reflection elements following a first envelope curve, wherein the reflection elements respectively comprise a reflective element surface arranged substantially parallel to a base surface and at least one flank adjoining the adjacent element surface or surfaces, and
wherein the base surface is oriented at an angle of inclination of at least 5° with respect to the base plane, and
wherein the element surfaces of adjacent elements are spaced in a direction perpendicular to the base surface such that the element surfaces of at least three adjacent elements each have a different height with respect to each other and with respect to the base surface with a first optical spacing or a plurality of the first optical spacing, wherein the first optical spacing is between 150 nm and 800 nm, and
wherein the first envelope curve has a spatial frequency of between 100 L/mm and 2000 L/mm and an optical depth at at least one location of more than 450 nm, wherein the optical depth is defined by the geometric difference between a minimum and a maximum perpendicular distance of the envelope curve with respect to the base plane, and the relief shape and the spatial frequency of the envelope curve are so selected that the incident light is diffracted into one or more first directions to represent a first item of information, the color value of which is further determined by the first optical spacing, and
wherein, in at least one second region, the surface structure is formed by a second surface relief, the second surface relief being an optically active surface relief which is not substructured by element surfaces such that the second surface relief differs from the first surface relief and which represents a second item of information, and
wherein the second surface relief is an achromatic surface relief comprising at least one of a matt structure, a macrostructure or a blaze grating.

13. A film element as set forth in claim 12 , wherein the first region has a smallest dimension of more than 50 μm.

14. A film element as set forth in claim 12 , wherein the first region is shaped in the form of one or more symbols or a portrait.

15. A film element as set forth in claim 12 , wherein the at least one second region adjoins the first region or regions.

16. A film element as set forth in claim 12 , wherein the first region entirely encloses the second region or the second region entirely encloses the first region.

17. A film element as set forth in claim 12 , wherein the first envelope curve is a one-dimensional grating and wherein the second region is formed by two or more second subregions which are of a strip-shaped configuration of a width of less than 300 μm, and wherein the second subregions are spaced from each other in accordance with a periodic second raster of a raster width of less than 300 μm

Assignees

• Tompkin Wayne Robert
• Schilling Andreas
• Ovd Kinegram Ag

Inventors

• Tompkin Wayne Robert
• Schilling Andreas

Classifications

• B42D25/328 Primary

  Diffraction gratings; Holograms · CPC title

• G02B5/1842 Primary

  Gratings for image generation (G02B5/1847 takes precedence) · CPC title

• B42D25/324

  Reliefs · CPC title

• B42D25/20

  characterised by a particular use or purpose · CPC title

• G02B5/18 Primary

  Diffraction gratings {(holographic optical elements G02B5/32, G03H; integrally combined with optical fibres G02B6/02057; for coupling light guides G02B6/34; integrally combined with optical integrated light guides G02B6/12; grating systems G02B27/44)} · CPC title