Compensator, Tunable, Dispersion
Sunday, September 03, 2006
The Tunable Dispersion Compensator (chromatic dispersion compensation) has been designed and developed using a virtually imaged phased array and is both tunable and wideband.
The Compensator light beam is from a single mode input Fiber Optic, which is collimated and focused with a half cylindrical lens to a line on a mirror glass plate. One side of the mirror glass plate has a 99.9 percent reflection coating except for a small window, where the light beam enters. The window is antireflection coated on both sides. The opposite side has a high reflective coating, so that a small amount of light is coupled out of the mirror glass plate at each reflection. After multiple reflections in the mirror glass plate, the light beams interfere to form a collimated light that has an angle dependent wavelength pattern. A lens mirror combination reflects the collimated light back to the mirror glass plate at a specific angle. The shape of the reflector and the incident angle of the collimated light beam determine this angle. The light beam returns to the mirror glass plate at a different position. This will produce a wavelength dependent time delay when the light beam is coupled back to the output Fiber Optic. Using various mirror glass plate designs and various focal lengths, the amount of dispersion and dispersion slope can be tuned by changing the distance between the focusing lens and the mirror glass plate.
Source: Avanex; AT & T
Reference: None Available
Industrial Products
posted by JD52 @ 12:30 AM,
