Abstract: A sprayable coating composition for a bare portion of an optical fiber that includes a refractive index grating having a characteristic wavelength response. A coating composition comprises a curable composition having a viscosity from about 0.05 Pa-sec to about 0.30 Pa-sec for spray application to cover the bare portion of the optical fiber, to protect the refractive index grating. A photoinitiator reacts with actinic radiation in the presence of oxygen to cure the curable composition covering the bare portion of the optical fiber. The characteristic wavelength response of the grating exhibits substantially linear variation between a lower limit of temperature and an upper limit of temperature when the curable composition has a glass transition temperature either above the upper limit of temperature or less than about 30° C. above the lower limit of temperature.

Abstract: A method for rapidly increasing the photosensitivity of an optical fiber comprising the step of providing an optical fiber comprising a glassy material and a thermally-stable coating. The thermally-stable coating has a thermally-stable exposure band, wherein desired time/temperature exposure parameters fall within the time/temperature thermal stability exposure band for the coating. The optical fiber is exposed for the desired time/temperature exposure to a hydrogen-containing atmosphere. The desired temperature is more than 250° C. and the desired time exposure does not exceed one hour. The glassy material then may be irradiated with actinic radiation, such that the refractive index of the irradiated portion results in a normalized index change of at least 10−5.

Abstract: A method for rapidly increasing the photosensitivity of an optical fiber comprising the step of providing an optical fiber comprising a glassy material and a thermally-stable coating. The thermally-stable coating has a thermally-stable exposure band, wherein desired time/temperature exposure parameters fall within the time/temperature thermal stability exposure band for the coating. The optical fiber is exposed for the desired time/temperature exposure to a hydrogen-containing atmosphere. The desired temperature is more than 250° C. and the desired time exposure does not exceed one hour. The glassy material then may be irradiated with actinic radiation, such that the refractive index of the irradiated portion results in a normalized index change of at least 10−5.