The invention provides a non-invasive skin treatment device (200) comprising: a light source (10) constructed for emitting treatment light (15), an optical system (20) constructed for focusing the treatment light along an optical axis (OA) to a focus position (320) inside the skin tissue (300), and an indenter (30) comprising a skin contact surface (34) having an aperture (A1) at a distance from the optical system for allowing the treatment light to be focused through the aperture into the skin tissue. The indenter is configured and constructed for generating, in a cross-section of the aperture taken along the optical axis and along a cross-section direction wherein the aperture has a width dimension, a maximally curved protrusion of skin tissue freely protruding through the aperture towards the optical system by pressing the indenter against the skin surface of a specific skin type with a pressure exceeding a predefined pressure, a skin surface of said maximally curved protrusion having a radius of curvature (RC) at an intersection with the optical axis. The optical system is configured and constructed for generating a focused beam of the treatment light having, in said cross-section of the aperture at said intersection, a wave front with a radius of curvature ranging between 75% and 125% of said radius of curvature (RC) of the skin surface of said maximally curved protrusion.Linvention concerne un dispositif de traitement de peau non invasif (200) comprenant : une source de lumière (10) conçue pour émettre une lumière de traitement (15), un système optique (20) conçu pour concentrer la lumière de traitement le long dun axe optique (OA) vers une position de concentration (320) à lintérieur du tissu cutané (300), et un pénétrateur (30) comprenant une surface de contact avec la peau (34) ayant une ouverture (A1) à une certaine distance du système optique pour permettre à la lumière de traitement dêtre concentrée à travers louverture dans le tissu cutané. Le pénétrate
