Abstract

Recently, we reported a technique for making a LP_0l → LP₁₁ fiber mode converter device.¹ The technique differs from holographic techniques^2,3 in that the periodic mode converter refractive index grating is written point-by-point in the, core of a two-mode photosensitive fiber with ultraviolet light, thereby allowing control of the pitch, length, and blaze of the perturbations. This paper provides further details on these fiber mode converters and reports the first direct observation of the index perturbations with thermoluminescence.

© 1991 Optical Society of America