Light therapy system for a treatment of the cornea and sclera for a noninvasive correction of a refractive system of an eye, comprising: a) a dispenser for dispensing an agent containing a photosensitizer on the cornea and sclera,; b) an imaging unit for 3D imaging of the cornea and sclera within an imaging volume, outputting image data; c) an image processing unit being adapted to receive the image data, to recognize a first collagen tissue structure; d) a UVA light source which is controllable and generates the UVA light with a first wavelength adapted to the photosensitizer and the crosslinking; e) an optical system adapted to the imaging unit and to the UVA light source, with an aperture as an outlet for the UVA light and as an inlet for the light from the imaging volume to the imaging unit, and providing a controllable deflection and focusing means for deflecting and focusing the UVA light on a focus point behind the aperture, such that said focus point can be controllably positioned within the imaging volume; and f) a processing and control unit adapted to control the optical system and the UVA light source; characterized in that g) the image processing unit is adapted to recognize a first orientation of respective collagen fibers or collagen fiber bundles within the first collagen tissue structure as a function of position; h) the processing and control unit is adapted - to receive data relating to a refractive error of the eye; - to determine a second collagen tissue structure with additional new corrective collagen crosslinks added to the first collagen tissue structure, such as to achieve a minimized refractive error of the eye; - to determine a UVA light energy as a function of the position, the new corrective collagen crosslinks and a growth factor for the new corrective collagen crosslinks, such that the growth of the new corrective collagen crosslinks is effected; and - to control the optical system and the UVA light source, such that the determined UVA light energy is applied within the cornea and sclera along the first orientation of the respective collagen fibers or collagen fiber bundles. a) a dispenser for dispensing an agent containing a photosensitizer on the cornea and sclera,; b) an imaging unit for 3D imaging of the cornea and sclera within an imaging volume, outputting image data; c) an image processing unit being adapted to receive the image data, to recognize a first collagen tissue structure; d) a UVA light source which is controllable and generates the UVA light with a first wavelength adapted to the photosensitizer and the crosslinking; e) an optical system adapted to the imaging unit and to the UVA light source, with an aperture as an outlet for the UVA light and as an inlet for the light from the imaging volume to the imaging unit, and providing a controllable deflection and focusing means for deflecting and focusing the UVA light on a focus point behind the aperture, such that said focus point can be controllably positioned within the imaging volume; and f) a processing and control unit adapted to control the optical system and the UVA light source; characterized in that g) the image processing unit is adapted to recognize a first orientation of respective collagen fibers or collagen fiber bundles within the first collagen tissue structure as a function of position; h) the processing and control unit is adapted - to receive data relating to a refractive error of the eye; - to determine a second collagen tissue structure with additional new corrective collagen crosslinks added to the first collagen tissue structure, such as to achieve a minimized refractive error of the eye; - to determine a UVA light energy as a function of the position, the new corrective collagen crosslinks and a growth factor for the new corrective collagen crosslinks, such that the growth of the new corrective collagen crosslinks is effected; and - to control the optical system and the UVA light source, such that the determined UVA light energy is applied within the cornea and sclera along the first orientation of the respective collagen fibers or collagen fiber bundles. - to receive data relating to a refractive error of the eye; - to determine a second collagen tissue structure with additional new corrective collagen crosslinks added to the first collagen tissue structure, such as to achieve a minimized refractive error of the eye; - to determine a UVA light energy as a function of the position, the new corrective collagen crosslinks and a growth factor for the new corrective collagen crosslinks, such that the growth of the new corrective collagen crosslinks is effected; and - to control the optical system and the UVA light source, such that the determined UVA light energy is applied within the cornea and sclera along the first orientation of the respective collagen fibers or collagen fiber bundles.