[c-nsp] [OT] Driving 1310nm optics through 1550nm circulators

[Mikael Abrahamsson]

On Wed, 9 Jan 2008, Gert Doering wrote:

> What are "optical circulators"?

http://en.wikipedia.org/wiki/Optical_circulator

"An optical circulator is a special fiber-optic component that can be used 
to separate optical powers that travel in opposite directions in one 
single optical fiber, analogous to the operation of an electronic 
circulator. An optical circulator is a three-port device that allows light 
to travel in only one direction—from port 1 to port 2, then from port 2 to 
port 3. This means that if some of the light emitted from port 2 is 
reflected back to the circulator, it is directed not back to port 1, but 
on to port 3. Circulators can also be used to achieve bi-directional 
transmission over a single fiber. Because of its high isolation of the 
input and reflected optical powers and its low insertion loss, optical 
circulators are widely used in advanced communication systems and 
fiber-optic sensor applications."

-- 
Mikael Abrahamsson    email: swmike at swm.pp.se