Nanophotonics is behaviour of light on the nanometer scale, and of the interaction of nanometer-scale objects with light. Optics, optical engineering, electrical-engineering, and nano-technology involves metallic components, which can transport and focus light. Nano-optics usually refers to situations involving ultraviolet, visible, and near-infrared light (free-space wavelengths from 300 to 1200 nanometers).

Think of nanophotonics is engineering light at a very, very small scale, or also known as a nanometer scale. As our human brains are not very good at conceptualizing how small a nanometer is, let’s put things into perspective: The average human head has around 100,000 hair follicles, and each hair follicle can grow 20 hair. On the other hand, the word nanophotonics refer to photons, the building block of light.