Security elements and methods of manufacture thereof

A security element comprising:

• a first layer having a first surface extending along a first direction and a second direction;
• an array of image regions across the first surface arranged along at least the second direction, each image region comprising at least a first image sub-region having an average inclination defining an angle, relative to a plane of the security element, about an image region axis extending along the first direction;
• a diffractive optically variable effect generating structure provided in or on the first surface across the first image sub-regions, the diffractive optically variable effect generating structure comprising diffractive elements that extend along a direction within 45° of the first direction,
• wherein the diffractive optically variable effect generating structure is provided across the first image sub-regions and spatially arranged and/or modulated across the first image sub-regions in accordance with a first image such that the first image is displayed by the first image sub-regions in combination at least at a first viewing angle,
• wherein the image regions define a two-dimensional array of image regions across the first surface, and
• wherein each sub-region within each image region defines a pixel of a corresponding image exhibited at a corresponding viewing angle.

A security element comprising:

• a first layer having a first surface extending along a first direction and a second direction;
• an array of image regions across the first surface arranged along at least the second direction, each image region comprising at least a first image sub-region having an average inclination defining an angle, relative to a plane of the security element, about an image region axis extending along the first direction;
• a diffractive optically variable effect generating structure provided in or on the first surface across the first image sub-regions, the diffractive optically variable effect generating structure comprising diffractive elements that extend along a direction within 45° of the first direction,
• wherein the diffractive optically variable effect generating structure is provided across the first image sub-regions and spatially arranged and/or modulated across the first image sub-regions in accordance with a first image such that the first image is displayed by the first image sub-regions in combination at least at a first viewing angle,
• wherein the array of first image sub-regions comprises an array of primary areas and an array of secondary areas,
• wherein the diffractive optically variable effect generating structure comprises a primary diffractive optically variable effect generating structure provided across the primary areas and a secondary diffractive optically variable effect generating structure provided across the secondary areas, and
• wherein the primary diffractive optically variable effect generating structure differs from the secondary diffractive optically variable effect generating structure in at least one of a pitch of the structure, an orientation of the structure and a size, a shape and/or a profile of the elements of the structure such that the primary and secondary areas appear different at least at the first viewing angle.

A security element comprising:

• a first layer having a first surface extending along a first direction and a second direction;
• an array of image regions across the first surface arranged along at least the second direction, each image region comprising at least a first image sub-region having an average inclination defining an angle, relative to a plane of the security element, about an image region axis extending along the first direction;
• a diffractive optically variable effect generating structure provided in or on the first surface across the first image sub-regions, the diffractive optically variable effect generating structure comprising diffractive elements that extend along a direction within 45° of the first direction,
• wherein the diffractive optically variable effect generating structure is provided across the first image sub-regions and spatially arranged and/or modulated across the first image sub-regions in accordance with a first image such that the first image is displayed by the first image sub-regions in combination at least at a first viewing angle, and
• wherein the or each sub-region within each image region has an average inclination that defines an angle of between 1° and 70° relative to the plane of the security element, about the image region axis extending along the first direction.