Method for manufacturing a security device, security device obtained by such a method, and identity document comprising such a device

A method for manufacturing a security device including at least a first image visible through an array of microlenses to an observer according to a first angle of observation, and a second image visible through the array of microlenses to the observer according to a second angle of observation, the second angle of observation being different from the first angle of observation, the method comprising:

• providing a window that is transparent to at least a part of visible light, the window comprising a front face and a rear face, the front face comprising an array of microlenses, each microlens of the array of microlenses having a focal length defining an object focal plane parallel to the front face and the rear face of the window;
• defining a global image comprising at least two patterns configured to represent the first image visible to the observer according to the first angle of observation through the array of microlenses and the second image visible to the observer according to the second angle of observation through the array of microlenses;
• disposing the global image relative to the array of microlenses;
• and
• engraving the global image through the rear face and between an engraving plane, defined by an upper tangent plane of the engraved image, and the rear face of the window by a laser beam incident on the rear face, the engraving plane being located between the front face of the window and the object focal plane of the microlenses and being distant from the rear face of the window by a distance that is less than or equal to one third of the focal length, the laser forming an engraving point according to an optical axis, the optical axis forming an angle of incidence with the rear face of the window.