5. Conclusion

At a time when the prefix "nano" is often used for media purposes, we have shown that, on the contrary, optics and photonics have resolutely entered the field of nanometric scales. At the end of the 1990s, no one could have imagined the production of optical microcavities with quality factors approaching one million, or the manufacture of microlasers with an active volume of less than a tenth of a cubic micrometer. Today, the manufacturing precision required to optimize the performance of these ultimate components is well into the nanometer range. Instrumental techniques for sub-wavelength analysis and manipulation have also become widespread. Micro-nanotechnologies have thus enabled the emergence of new optical functionalities, and opened up the prospect of large-scale integration of optical components in the same way as electronic components in microprocessors. From this point of view,...