Abstract: An optical fiber cascaded Raman laser scheme is provided. An optical fiber cascaded Raman laser scheme in accordance with an embodiment of the present invention includes a pump light source, an optical fiber, a wavelength division multiplexing optical fiber combiner, another wavelength division multiplexing optical fiber combiner, a short period optical fiber bragg grating, a long period bragg grating, first means, and second means. The pump light source generates pump light. The optical fiber causes Raman scattering regarding the optical pump light as nonlinear material. The wavelength division multiplexing optical fiber combiner forms intra cavity regarding light of second order stoke frequency shifted wavelength. The light is stoke frequency shifted by Raman scattering of the optical fiber. The another wavelength division multiplexing optical fiber combiner forms intra cavity regarding light of first and third order stoke frequency shifted wavelength.

Abstract: A dual wavelength optical fiber laser includes a first and a second optical fibers which generating stimulated scattering by a pump light source; two short period optical fiber gratings that is resonating each of a first and a second wavelength light which are generated by the optical fibers and regulating reflecting characteristics according to the first and the second wavelengths; a WDM optical fiber coupler which inputs a pump wavelength to the optical fibers and outputs a laser operation wavelength; and an interference removing unit which is connected between the optical fibers and removes an interference in the first and the second wavelength of resonating.

Abstract: An optical fiber mode-locked laser is disclosed. The laser comprises a gain medium doped optical fiber to achieve a population inversion between high and low energy levels by a pump light source and to oscillate optical waves in sequence, a cholesteric liquid crystal circular polarization mirror to transmit the waves from the pump light source and to be operated as a circular polarization reflection mirror for the oscillated optical waves from the gain medium doped optical fiber, a polarization controller to control the polarization state of the proceeding light which is oscillated from the gain medium doped optical fiber, a dispersion shifted fiber to give a non-linear effect to the proceeding light through the polarization controller, and an optical fiber laser output mirror which forms a resonator by putting out some portion of the proceeding light by transmission and reflecting the other portion of the light.

Abstract: The present invention relates to an optical fiber amplifier incorporating therein a wavelength division multiplexer and a plurality of diffraction grating pairs for generating a number of optical signals with a pumping light of one wavelength, each optical signal having a different wavelength. The optical device includes a first optical means for guiding the first pumping light and the optical signals, a second optical means for generating a second pumping light with the first pumping light and generating the plurality optical signals with the second pumping light, and an optical coupler for introducing the first pumping light into the second optical means and outputting the optical signals.

Abstract: A mode-locked fiber laser and a fiber amplifier using a single pump laser, the fiber laser using a pump source to generate soliton optical short pulse and the fiber amplifier amplifying the optical short pulse. The mode-locked fiber laser and fiber amplifier use a single pump laser in accordance with an embodiment of the present invention that includes a tunable directional coupler, a mode-locked fiber laser, and an optical amplifier. The tunable directional coupler is connected to the pump source. The mode-locked fiber laser receives the pump output of the pump source and generates a soliton optical pulse. The mode-locked fiber laser is connected to an output port of the tunable directional coupler. The optical amplifier receives the pump output of the pump source, receives the soliton optical pulse generated by the mode-locked fiber laser, and amplifies the soliton optical pulse. The optical amplifier is connected to the other output port of the tunable directional coupler.

Abstract: An apparatus for measurement of an optical pulse shape intended to measure the temporal waveform of an ultrashort single optical pulse is disclosed. The present invention comprises a linearly chirped supercontinuum light source that is synchronized with an optical pulse to be measured; a nonlinear optical interferometer to transform the temporal waveform of an incident optical pulse into a spectrum using an incident light from said supercontinuum light source; and an optical spectrum analyzer to measure the wavelength of the light passing through the nonlinear interferometer so that it can measure the temporal waveform of a single optical pulse. The present invention employs the method that transforms the temporal waveform of an incident optical pulse into a spectrum and measures the wavelength using a linearly chirped supercontinuum light source, a nonlinear optical interferometer, and an optical spectrum analyzer.

Abstract: The present invention provides a tunable optical filtering system using fiber-optic polarimetric interferometer. The tunable optical filtering system using fiber-optic polarimetric interferometer in accordance with the present invention comprises a stabilization light source, a first polarization beam splitter, a first optical fiber node, a number of polarization maintaining optical fibers, a phase modulator, a stabilization electronics, a second optical fiber node, a second polarization beam splitter, and two wavelength division optical multiplexers. The stabilization light source supplies stabilization light. The first polarization beam splitter polarizes the stabilization light and the input light to be filtered and generates polarized light. The first optical fiber node connects the output of the first polarization beam splitter with polarization maintaining fibers with the angle of 45 degree between their birefringent axes and splits the polarized light.

Abstract: The present invention provides a demultiplexer for generating a constant four-wave-mixing beam without regard to an input polarization state using a dispersion-shifted fiber that is a nonlinear material with high refractive index. A number of parts in conventional demultiplexer implementations, which are sensitive to input polarization state has been replaced with optical fibers of high polarization mode dispersion.

Abstract: An optical fiber Mach-Zehnder interferometer optical filter is disclosed.

Abstract: The present invention discloses an all-optical wavelength converter using a semiconductor optical amplifier and a polarization interferometer. The all-optical wavelength converter using a semiconductor optical amplifier and a polarization interferometer including a wavelength converter which modulates a probe light into a inverting waveform to a signal light and outputs the modulated light by using cross gain modulation, a phenomenon that occurs while the signal light and the probe light pass together through an optical splitter/combiner, a semiconductor optical amplifier and a filter at the same time, a polarization interferometer which makes the probe light outputted from the wavelength converter and having the inverting waveform to the signal light undergo a double-refraction so that a predetermined time split occurs on it and provides a non-inverting wavelength conversion and suppresses the slow XGM components in the converted outputs due to the slow carrier recombination time.

Abstract: The present invention discloses an optical fiber laser and a method of harmonic mode locking utilizing the optical fiber laser, which is capable of locking a harmonic frequency occurred by inserting an optical modulator between a Faraday rotator mirror and a non-linear amplifying loop mirror to coincide the frequency component of the optical modulator with the frequency component of the longitudinal mode of the laser. In order to achieve the object of the present invention, it comprises an optical fiber laser which comprises a non-linear amplifying loop mirror, a linear mirror and an optical fiber directional coupler or fiber coupler.

Abstract: A hybrid type passively and actively mode-locked laser scheme is disclosed, in which not only the capability of producing ultra-short optical pulses by the conventional passively mode-locked optical fiber laser scheme is utilized, but also the repetition rate variation capability and the optical pulse synchronization capability of the conventional actively mode-locked laser scheme are utilized. Consequently, all the advantages of the two conventional laser schemes are obtained in the present invention. Specifically, two loops are coupled together, and one of the two loops consists of a non-linear amplifying loop of the existing passively mode-locked scheme, while the other loop includes an optical modulator and an optical gain medium for the loop to perform the function of an actively mode-locked scheme. Further the other loop includes a time delay line so as to adjust the laser oscillation repetition rate.

Abstract: The wavelength tunable mode-locking optical fiber laser comprises non-linear amplifying loop mirror part having a light pumping lase diode, a gain medium doped optical fiber having the gain medium for oscillating the rambling light wave sequentially, a dispersion shifted optical fiber, and first polarization controller for making the continuous oscillation light wave to be maximized by adjusting the polarization of said propagating light. All elements of the non-linear amplifying loop mirror part are combined to each other in loop type on the above clock direction.

Abstract: An optical fiber laser is disclosed capable of generating an ultrashort pulse which has intensive energy and is stable against polarization by using a sagnac loop mirror and a Faraday rotator mirror, which includes a light pumping laser diode; an erbium doped fiber-added optical fiber; a wavelength division multiplier fiber coupler; a dispersion shifted fiber; and an optical fiber directional coupler; a nonlinear amplifier loop mirror; a second polarization controller; a linear mirror having a Faraday rotator mirror for rotating the polarization plane of a proceeding light wave; and a directional coupler being connected between the nonlinear amplifier loop mirror and the linear mirror.

Abstract: A fiber-optic address detector comprises fiber-optic delay lines on one surface of which a metal thin film is evaporated, the fiber-optic delay lines being connected in a melting state to fiber-optic couplers, wherein inputting address photonic signals are tapped by the inputting fiber-optic couplers, reflected by the metal thin films at the end portion of the fiber-optic delay line and then re-combined by the inputting fiber-optic coupler, whereby it can reduce the number of the fiber-optic coupler used in the conventional fiber-optic address detector to one half as well as obtain the same address detection effect.