Fabrication Of Long-period Gratings Research Articles

Fabrication of long-period gratings with a mercury-arc lamp

Long-period gratings (LPGs) were fabricated in hydrogen-loaded standard single-mode fibers by use of a broadband UV mercury-arc lamp. Several kinds of LPGs with loss of ∼50% were fabricated in 40 min. With this technology, LPGs can be mass produced at very low cost.

Recording of long-period gratings in special single-mode fibers by a CO 2 laser

The paper deals with the fabrication of long-period gratings (LPG) in special optical fibers with an inverted parabolic-index profile of the cladding by periodically exposing the fibers to radiation of a high-power CO 2 laser. Details on the fiber fabrication and preparation of LPGs with a period of about 1 mm in the fibers are presented. The fabricated LPGs were evaluated on the basis of their transmission spectra determined by measuring the output spectral density of the fiber with the LPGs. It is shown that the position of the band and its strength depend on the laser beam velocity, beam power and the interaction time of radiation with the fiber.

Fabrication of long-period gratings in poly(methyl methacrylate-co-methyl vinyl ketone-co-benzyl methacrylate)-core polymer optical fiber by use of a mercury lamp

Polymer optical fiber (POF) with a highly photosensitive poly(methyl methacrylate-co-methyl vinyl ketone-co-benzyl methacrylate) core is fabricated. Gratings can be fabricated in the core of a POF with a low-cost mercury lamp. The part of the emission spectrum of the mercury lamp in which the cladding material exhibits photosensitivity is effectively filtered by a 1.5-mm-thick Pyrex glass to ensure that a long-period grating is formed only in the core of a POF. A long-period grating with a 3-dR resonant peak at 1568 nm is fabricated with 0.3 mW/cm2 of UV irradiation over a period of 200 s.

Strong 157 nm F 2 -laser photosensitivity-locking of hydrogen-loaded telecommunication fibre for 248 nm fabrication of long-period gratings

Strong (>20 dB) long-period fibre gratings were fabricated by combining F/sub 2/-laser photosensitivity-locking of hydrogen-soaked telecommunication fibre and KrF-laser grating formation. The 157 nm pretreatment permanently enhances the fibre photosensitivity response to the low-energy 248 nm photons. Thermal annealing at 120/spl deg/C for 24 h improves the grating stability without diminishing the enhancement.