We'd like to image the output face (the core area) of a fiber onto the input face (core) of an identical fiber with the highest coupling efficiency possible. The wavelength is800 nm. What is the best method to achieve this?
I could think of the following two.1- Use double aspheric (two identical aspheres) with NA equal to the fiber's NA.
2-Use a single imaging GRIN lens that has the same NA as that of the fiber. Can GRIN lens handle high power light i.e. keep its refractive index profile intact?
Appreciate your comment and suggestions.