Printing an authentication pattern with multi-deflection continuous inkjet printer

An authentication pattern of an object, printed on a printing substrate, said printing substrate being a surface of said object or of a packaging of said object, the authentication pattern being defined by a group of white and black pixels, said authentication pattern comprising:

• a succession of rasters spaced apart in a direction X as per a raster pitch,
• wherein each raster has a direction substantially parallel to a direction Y perpendicular to direction X,
• wherein all the black pixels of a raster are disposed at a distance from an axis of direction X that is continuously between a minimum distance and a maximum distance, and
• wherein each raster comprises no more than three black pixels.

A marking printed on a printing substrate, said printing substrate being the surface of an object or of a packaging of said object, said marking comprising a group of white and black pixels, and comprising a succession of rasters spaced apart in a direction X, each raster having a direction substantially parallel to a direction Y substantially perpendicular to direction X, said marking comprising:

• a first zone comprising an identification marking of said object, said identification marking being defined by a group of white and black pixels, said identification marking comprising a succession of rasters spaced apart in a direction X as per a raster pitch, each raster having a direction substantially parallel to a direction Y perpendicular to direction X;
• and
• a second zone associated with each said identification marking and comprising an authentication pattern of said object, printed on a printing substrate, said printing substrate being a surface of said object or of a packaging of said object, the authentication pattern being defined by a group of white and black pixels, said authentication pattern comprising
• a succession of rasters spaced apart in a direction X as per a raster pitch,
• wherein each raster has a direction substantially parallel to a direction Y perpendicular to direction X,
• wherein all the black pixels of a raster are disposed at a distance from an axis of direction X that is continuously between a minimum distance and a maximum distance, and
• wherein each raster comprises no more than three black pixels.

A method for printing at least one authentication pattern of an object on a printing substrate, said printing substrate being the surface of said object or of a packaging of said object, using a multi-deflection continuous inkjet printer or a print head of said printer, said pattern comprising a group of white and black pixels, the method comprising:

• printing a succession of rasters spaced apart in a direction X as per a raster pitch,
• wherein each said raster has a direction substantially parallel to a direction Y substantially perpendicular to direction X,
• wherein all the black pixels of one raster are disposed at a distance from an axis of direction X that is continuously between a minimum distance and a maximum distance, and
• wherein each said raster comprises no more than three black pixels.

A method comprising:

• printing, using a multi-deflection continuous inkjet printer or a print head of said printer, a first zone comprising an identification marking defined by a group of white and black pixels, said identification marking comprising a succession of rasters spaced apart in a direction X as per a raster pitch, each raster having a direction substantially parallel to a direction Y perpendicular to direction X;
• and
• printing a second zone associated with each identification marking and comprising an authentication pattern,
• wherein said printing of the second zone comprises
• printing a succession of rasters spaced apart in a direction X as per a raster pitch,
• wherein each said raster has a direction substantially parallel to a direction Y substantially perpendicular to direction X,
• wherein all the black pixels of one raster are disposed at a distance from an axis of direction X that is continuously between a minimum distance and a maximum distance, and
• wherein each said raster comprises no more than three black pixels.

A multi-deflection continuous inkjet printer or print head of said printer, comprising:

• an ink circuit;
• a print head;
• and
• control and command means configured to
• print a succession of rasters spaced apart in a direction X as per a raster pitch,
• wherein each said raster has a direction substantially parallel to a direction Y substantially perpendicular to direction X,
• wherein all the black pixels of one raster are disposed at a distance from an axis of direction X that is continuously between a minimum distance and a maximum distance, and
• wherein each said raster comprises no more than three black pixels.

A permanent storage medium storing data readable by a computer or by command means of a multi-deflection continuous inkjet printer, or plurality of such media, the data notably comprising instructions executable by the printer command means and which when executed make a multi-deflection continuous inkjet printer capable of implementing a method comprising:

• printing a succession of rasters spaced apart in a direction X as per a raster pitch,
• wherein each said raster has a direction substantially parallel to a direction Y substantially perpendicular to direction X,
• wherein all the black pixels of one raster are disposed at a distance from an axis of direction X that is continuously between a minimum distance and a maximum distance, and
• wherein each said raster comprises no more than three black pixels.

A multi-deflection continuous inkjet printer, comprising:

• an ink circuit;
• a print bead coupled to said ink circuit;
• and
• a controller operably coupled to said print head,
• wherein said controller is configured to print, using said print bead of said printer, at least one marking on a printing substrate, said at least one marking including a group of white and black pixels, and a succession of rasters spaced apart in a direction X as per a raster pitch, each said raster having a direction substantially parallel to a direction Y substantially perpendicular to direction X, said at least one marking comprising
• a first zone comprising an identification marking of said object;
• and
• a second zone associated with said identification marking and comprising an authentication pattern,
• wherein all said black pixels of a raster of said authentication pattern are disposed at a distance from an axis of the direction X that is continuous between a minimum distance and a maximum distance, and
• wherein each raster comprising no more than three black pixels;
• and
• wherein said print head is configured to form bursts of droplets for each of the marking zones, each bunt forming a raster on the printing substrate, each said burst being formed at a first frequency for the first zone, and at a second frequency higher than the first frequency for the second zone.