Security document comprising a perforated opaque layer with a white appearance above a matrix of coloured sub-pixels
A security document having a stack of layers including a matrix of coloured sub-pixels, an opaque layer with a white appearance above the matrix of coloured sub-pixels, the opaque layer with a white appearance having perforations facing sub-pixels of the matrix of coloured sub-pixels such that, when the device is observed from above, a coloured image appears.
1 . A security document comprising:
a stack of layers having a matrix of coloured sub-pixels;
an opaque layer with a white appearance above the matrix of coloured sub-pixels; and
a laserable layer arranged above the opaque layer with a white appearance and configured to be laserized by applying a laser beam at at least one laserization wavelength,
wherein the opaque layer with a white appearance includes perforations facing sub-pixels of the matrix of coloured sub-pixels such that, when the security document is observed from above, a coloured image appears,
wherein the perforations pass through the opaque layer, and
wherein the laserable layer comprises portions that are blackened by laserization.
2 . The security document according to claim 1 , further comprising a filter limiting passage of at least the laserization wavelength, the filter being arranged between the laserable layer and the opaque layer with a white appearance, or
wherein the laserable layer is configured to form the filter limiting the passage of at least the laserization wavelength.
3 . The security document according to claim 1 , wherein the opaque layer with a white appearance is chosen to be perforated by a laser beam with a perforation wavelength.
4 . The security document according to claim 1 , wherein a perforation wavelength is different from the laserization wavelength.
5 . The security document according to claim 1 , wherein a pixel of the coloured image includes a coloured sub-pixel visible through a perforation and a portion with a white appearance of the opaque layer with a white appearance forming a white sub-pixel of the pixel.
6 . A method for manufacturing a security document, comprising:
assembling a matrix of coloured sub-pixels with, above the matrix of coloured sub-pixels, an opaque layer with a white appearance; and
forming perforations through the opaque layer with a white appearance and facing sub-pixels of the matrix of coloured sub-pixels such that, when the security document is observed from above, a coloured image appears,
wherein the perforations pass through the opaque layer and the opaque layer includes a metal oxide,
wherein a laserable layer is furthermore assembled above the opaque layer with a white appearance and configured to be laserized by applying a laser beam at at least one laserization wavelength, and
wherein the laserable layer is laserized to obtain blackened portions.
7 . The method according to claim 6 , wherein a filter limiting passage of at least the laserization wavelength is furthermore assembled between the laserable layer and the opaque layer with a white appearance, or
wherein the laserable layer is configured to form the filter limiting the passage of at least the laserization wavelength.
8 . The method according to claim 6 , wherein the opaque layer with a white appearance is perforated by a laser beam with a perforation wavelength to obtain the perforations.
9 . The method according to claim 6 , wherein a perforation wavelength is different from the laserization wavelength.
10 . The method according to claim 6 , further comprising, in a registration phase, observing a position of a group of coloured sub-pixels prior to formation of the perforations that form the coloured image.
11 . The method according to claim 10 , wherein the coloured sub-pixels of the group of coloured sub-pixels are observable through one or more perforations in the opaque layer with a white appearance.
12 . The method according to claim 6 , wherein a set of trenches is formed in a grid-shaped pattern through the opaque layer with a white appearance.
13 . The method according to claim 10 , wherein the position of the group of coloured sub-pixels is observed through trenches.
14 . A security document comprising:
a stack of layers having a matrix of coloured sub-pixels; and
an opaque layer with a white appearance above the matrix of coloured sub-pixels,
wherein the opaque layer with a white appearance includes a trench and perforations facing sub-pixels of the matrix of coloured sub-pixels such that, when the security document is observed from above, a coloured image appears,
wherein the perforations pass through the opaque layer and the opaque layer includes a metal oxide, and
wherein the trench is independent from the perforations.