4. Conclusion

Photonic functions and systems are part of our society. They form the basis of modern telecommunications technologies, and perform the functions of transporting, multiplexing, converting and transforming information using light. There is a certain analogy with electronic circuits, where the flow of electrons is replaced by the flow of photons, and information is encoded in phase, amplitude, wavelength and polarization. To make the most of the photon's characteristics, the current challenge is to move optical design towards 3D systems, where the potential of highly focused ultrashort laser pulses comes into its own. The technique offers great flexibility in terms of substrate choice and process parameters, while also showing great potential for mass production. Dozens of research teams and industrial players are now involved in this field. This article only slightly reveals the potential...