Patent ID: 6532773
Filing Date: 2003-03-18
Classification: C03B,Y02P

Abstract:
Process for fabricating an optical preform having a desired index profile that is uniform in the longitudinal direction, said process comprising the following steps:(i) depositing successive layers of core material onto the interior wall of a precursor glass tube, said core material having a refractive index profile whose magnitude varies from the outer deposited layers to the inner deposited layers; (ii) collapsing the central hole of the precursor glass tube to form a precursor optical preform, and drawing a length of fiber therefrom; (iii) determining the refractive index profile of the core of the drawn fiber at various locations along its length; (iv) calculating the amount of core material that needs to be removed from the inner deposited layers at locations of the precursor perform corresponding to each of the various locations to convert the index profile of the precursor preform into the desired index profile; (v) depositing successive layers of core material onto the interior wall of a second glass tube, said core material having a refractive index profile whose magnitude varies from the outer deposited layers to the inner deposited layers in a manner substantially identical to the profile of a precursor optical preform; and (vi) removing the calculated amounts of core material from the inner deposited layers of the second glass tube at locations corresponding to each of the locations of the precursor preform, and collapsing the central hole of the second glass tube to form the second optical preform.