The term photonics was 1st developed from the practical semiconductor light emitters in the early 1960s .A photonic network uses light as a source to convey the information instead of electronic signals. Photonics is related to quantum electronics. A photonic device component uses laser diodes, optical amplifiers, LED’s and photovoltaic cells for creating, manipulating or detecting light. Photonic crystals are defined as periodic optical nanostructures which uniformly affect the motion of photons .

Photonics is the science and practice of manipulating photons which can be made as small packets of light.


1. The light will travel thousand times faster than that of electrons in computer chips.

2. By using this , the transmission bandwidth can be increased than conventional copper wires.

3. No electromagnetic interference.


• Crystal is made of low-loss periodic containing dielectric medium .

• It is optical analog for the electrical semiconductors.

• Has the ability for localizing light in specified areas which prevents light from propagating in certain directions.


(PCF) Photonic crystal fibers (PCFs) are optical fibers that employ a microstructured arrangement in a background material of different refractive index. The background material is often undoped silica and a low index region is typically provided by air voids running along the length of the fiber. It is a crystal fiber that combines the properties of 2D photonic crystals and classic fibers. It is also known as microstructured fiber ( very small structured) or holes fiber ( due to air holes in its construction). It has two categories namely ,

1. Index guiding

2. Photonic bandgap.


Photonic crystals are nanoscale structures which depends on the frequency of their dielectric constants either allow or block individual wavelengths of light. In this each wavelength of light has a unique physical size, which causes them to appear as different colors. For satisfying the calculated wavelength to penetrate through a photonic crystal’s structure, it should be compatible with the crystal’s dielectric fields.


Photonic crystals use as biosensors, safe and well approach to target. Thus , the photonic crystals are going to be a future semiconductors which has many applications irrespective of their fields.