Method for making a self-aligned optical guide between an optical source producing a directional emission and an optical fiber, comprising the following steps: - arranging the optical source and the optical fiber facing one another and defining an intermediate space between them, the optical source being configured to emit a first light having a first peak wavelength comprised between 700 nm and 1600 nm; - placing, in the intermediate space, a fluid guide forming composition in contact with the optical source and with the optical fiber, the guide forming composition comprising a first monomer, a first photoinitiator system able to activate the polymerization of the first monomer when illuminated with the first light and a second photoinitiator system being able to activate the polymerization of the first monomer when illuminated with a second light having a second peak wavelength, the second photoinitiator system not interacting with the first photoinitiator system when the first photoinitiator system is illuminated with the first light, the difference between the first peak wavelength and the second peak wavelength being more than 100 nm, - injecting the first light in the guide forming composition from the optical source and/or from the optical fiber, to harden a central region of the optical guide by photopolymerization of the first monomer initiated by the first photoinitiator system, the central region connecting the optical source and the optical fiber, - illuminating the guide forming composition with the second light to harden a peripheral region of the optical guide by photopolymerization of the first monomer initiated by the second photoinitiator system; - arranging the optical source and the optical fiber facing one another and defining an intermediate space between them, the optical source being configured to emit a first light having a first peak wavelength comprised between 700 nm and 1600 nm; - placing, in the intermediate space, a fluid guide forming composition in contact with the optical source and with the optical fiber, the guide forming composition comprising a first monomer, a first photoinitiator system able to activate the polymerization of the first monomer when illuminated with the first light and a second photoinitiator system being able to activate the polymerization of the first monomer when illuminated with a second light having a second peak wavelength, the second photoinitiator system not interacting with the first photoinitiator system when the first photoinitiator system is illuminated with the first light, the difference between the first peak wavelength and the second peak wavelength being more than 100 nm, - injecting the first light in the guide forming composition from the optical source and/or from the optical fiber, to harden a central region of the optical guide by photopolymerization of the first monomer initiated by the first photoinitiator system, the central region connecting the optical source and the optical fiber, - illuminating the guide forming composition with the second light to harden a peripheral region of the optical guide by photopolymerization of the first monomer initiated by the second photoinitiator system;