When laser pens twisted, the hollow channel effect of the helical array in the light, similar to that described by general relativity, when light travels through the stars will occur due to gravitational bending in space.
The optical fiber as an internal laser pens. like pipeline light by wall, usually with a light guide fiber core, the refractive index of glass fiber rate higher than the refractive glass outer layer closed. The refractive index difference will cause the light reflection in the cladding interface, and trapped in tube shaped fiber in the core. The team LED for the first time the light guide without core photonic crystal fiber.
A typical laser pens consists of a piece of glass, a regular periodic array of holes in the glass and air volume. Due to the different refractive index and refractive index with periodic structure. This is the material called crystal, their atoms form a three-dimensional lattice ordered in the crystal salt or for example. In the conventional silicon crystal, such as insulator, conductor and semiconductor, the precise design of 3D structure determines the behavior of electrons.
The three-dimensional structure depends on the optical properties of a laser pens to periodically, in some butterfly wings, this structure determines the butterflies sparkling color. The optical properties to control material is very useful in a wide variety of applications. Developed by Philip Russell and his team of Marx Planck in Erlangen the visible spectra of the photonic crystal fiber can be used to filter specific wavelength or produce super white light.