Origins of Photonics
The word 'photonic' was coined to describe components and systems that operate with photons in the same way that the word 'electronic' describes components and systems that operate with electrons.
By their nature, photonic components and systems are optical in the same way that electronic systems are electrical. Their is however a subtle difference between a system or component being optical or the subset of optical that would be considered photonic. The difference is that photonic components are generally concerned with light or optical signals, their generation, manipulation and detection. There is an implied level of complexity in this that is absent in a simple optical light source such as an electric light bulb.
Of course this definition is not rigorous and the bounderies of photonics are ill-defined. The term opto-electronics has been partly displaced by the term photonics in the buzz-words of the 21st century, and yet several photonic devices actually use some electrical power or electronic signals or control, and so are opto-electronic rather than being wholly photonic. The poor house-hold light bulb is one of the first examples of an electrical and optical, hence opto-electronic, device, yet there are no incandescent light-bulb manufacturers we know of who would claim this to be an opto-electronic or photnic business.