Abstract: A laser system according to an embodiment of the present invention includes an oscillation unit to generate a laser output, a connection unit to connect the oscillation unit with an optical fiber loop, an amplifying unit to amplify the laser output on the optical fiber loop, a conversion unit disposed on the optical fiber loop to convert pulsed wave laser output into continuous wave laser output, and an output unit disposed between the connection unit and the conversion unit to split a part of the laser output toward the conversion unit. The system for generating a high output pulsed wave laser and converting the pulsed wave laser into a continuous wave laser may be implemented in a simple structure and small size with high stability and high reproducibility. In addition, a high output laser may be obtained. Also, since conversion from the pulsed wave into the continuous wave is easy, both of the high output pulsed wave and the high output continuous wave may be obtained as necessary.

Abstract: A laser system according to an embodiment of the present invention includes an oscillation unit to generate a laser output, a connection unit to connect the oscillation unit with an optical fiber loop, an amplifying unit to amplify the laser output on the optical fiber loop, a conversion unit disposed on the optical fiber loop to convert pulsed wave laser output into continuous wave laser output, and an output unit disposed between the connection unit and the conversion unit to split a part of the laser output toward the conversion unit. The system for generating a high output pulsed wave laser and converting the pulsed wave laser into a continuous wave laser may be implemented in a simple structure and small size with high stability and high reproducibility. In addition, a high output laser may be obtained. Also, since conversion from the pulsed wave into the continuous wave is easy, both of the high output pulsed wave and the high output continuous wave may be obtained as necessary.

Abstract: Disclosed herein is a functional tunable multichannel filter which is capable of adjusting channel spacing and/or a wavelength location using polarization controllers (?/2, (?/4). The functional tunable multichannel filter includes one or more polarization maintaining fibers, a first polarization controller (?/2), a second polarization controller (?/4) and a 3 dB coupler. Additionally, the functional tunable multichannel filter is configured to tune a wavelength and adjust channel spacing by adjusting polarization of an optical signal passing through each of the polarization maintaining fibers using the first and second polarization controllers.

Abstract: Disclosed are a continuous wave supercontinuum laser source resonator using low-priced multimode semiconductor lasers as pumping light and applying a rare-earth doped optical fiber and a Highly Nonlinear Dispersion Shifted Fiber (HNL-DSF) to a ring resonator structure to embody a continuous wave supercontinuum light source, and a medical diagnostic apparatus using the same. The resonator consists of a pump combiner for inputting pumping light into the resonator; a rare-earth doped optical fiber for receiving and converting the pumping light into seed light of a predetermined wavelength band; a Highly Nonlinear Dispersion Shifted Fiber (HNL-DSF) for converting the light converted by the rare-earth doped optical fiber and oscillating in the resonator into a continuous wave supercontinuum laser source; and a coupler for outputting the supercontinuum laser source generated from the Highly Nonlinear Dispersion Shifted Fiber (HNL-DSF).

Abstract: Provided is a tunable dispersion compensator based on an optical fiber grating for use in an optical transmission system. A tunable dispersion compensator comprises: a disk; a ring surrounding the disk, wherein the ring is rotatable independent of the disk; and a bendable plate crossing the disk and having end parts configured to move with the rotation of the ring, wherein at least one of the optical fiber grating is attached to the plate.

Abstract: The present invention relates to a tunable distribution compensator, including: an optical fiber having a chirped optical fiber grating; first and second frames having first and second stepped portions, respectively, wherein the first stepped portion is symmetrically faced to the second stepped portion; a first metal plate with a predetermined length for attaching the optical fiber; a second metal plate seated on the first and second stepped portions; and a bending unit connected to the first and second frames and the second metal plate for symmetrically bending the optical fiber.

Abstract: Disclosed are a Raman or erbium-doped fiber laser using a few-mode fiber grating, and a long-distance remote sensor using the same that can simultaneously measure temperature and strain by separating temperature and strain components using Raman amplification or erbium amplification. When a multi-wavelength Raman or erbium-doped laser is configured by means of a short-period fiber grating serving as a few-mode fiber grating at one side of a resonator and a chirped fiber Bragg grating or tunable chirped fiber Bragg grating at the other side of the resonator, multi-wavelength laser signals are generated in different modes. Because wavelength shift and reflectivity vary with a change in temperature and strain, temperature and strain components can be simultaneously measured. Because an optical fiber of several tens of kilometers is used, it can be utilized as a sensing probe of the long-distance remote sensor.

Abstract: The present invention relates to a tunable distribution compensator, including: an optical fiber having a chirped optical fiber grating; first and second frames having first and second stepped portions, respectively, wherein the first stepped portion is symmetrically faced to the second stepped portion; a first metal plate with a predetermined length for attaching the optical fiber; a second metal plate seated on the first and second stepped portions; and a bending unit connected to the first and second frames and the second metal plate for symmetrically bending the optical fiber.

Abstract: Provided is a tunable dispersion compensator based on an optical fiber grating for use in an optical transmission system. A tunable dispersion compensator comprises: a disk; a ring surrounding the disk, wherein the ring is rotatable independent of the disk; and a bendable plate crossing the disk and having end parts configured to move with the rotation of the ring, wherein at least one of the optical fiber grating is attached to the plate.

Abstract: An erbium-doped optical fiber (EDF) and a fabricating method thereof The erbium-doped optical fiber has a core formed by substantially doping silica with erbium and having gratings formed therein at a predetermined period, for propagating light therethrough, and a cladding surrounding the core and having a lower refractive index than the core. Since the erbium-doped optical fiber acts as a gain flattening filter, an erbium-doped fiber amplifier formed out of the erbium-doped optical fiber obviates the need of splicing an erbium-doped optical fiber with a gain flattening filter.

Abstract: A multi-cladding optical fiber, a long-period optical fiber grating written in the optical fiber, and a writing method thereof are provided. The multi-cladding optical fiber includes a core made of germanium-doped silica (GeO2—SiO2), for guiding light, an inner cladding made of fluorine-doped silica (F—SiO2), the inner cladding having a refractive index smaller than that of the core and surrounding the core, and an outer cladding made of silica, the outer cladding having a refractive index smaller than that of the core and larger than that of the inner cladding and surrounding the inner cladding. Therefore, an optimized optical fiber can be designed. That is to say, an optical fiber having desired characteristics can be fabricated by adjusting at least one of the parameters including the amount of F doped into the inner cladding, the thickness of the inner cladding, the amount of GeO2 doped into the core, the composition of SiO2 in the outer cladding and the drawing tension of the optical fiber.