National Yang Ming Chiao Tung University

National United University

Nan-Kuang Chen

Sien Chi

Shiao-Min Tseng

Yinchieh Lai

Jow-Tsong Shy

Hsi-Wen Yang

Jing-Shyang Horng

Zhi-Zheng Feng

Jim-Wein Lin

Fu-Yu Tsai

Chien-Yuan Han

The present invention provides a method for producing a Mach-Zehnder filtering device. The method includes the following steps: (a) providing an optical fiber having a jacket and a core containing rare earth element dopants; (b) stripping the jacket of a segment of the optical fiber; and (c) performing a fused-tapering to the stripped segment of the optical fiber to form a first and a second necks simultaneously, wherein the core exists in both the first and the second necks to form a Mach-Zehnder interferometer.

Single fiber mach-zehnder filter and method of manufacturing the same

A cladding-pumped gain optical fiber is provided. The cladding-pumped gain optical fiber includes a core transmitting a signal light; a first cladding covering the core and having an optical-gain dopant; a second cladding covering the first cladding for transmitting a pumping light; and a third cladding covering the second cladding for reflecting the pumping light.

Cladding-pumped evanescent gain optical fiber

A wavelength-tunable mode-locked fiber laser system is provided and includes an optical cavity. The optical cavity outputs an output laser pulse having an adjustable principal wavelength, and includes a short-wavelength-pass filter, a polarization controller, an optical gain fiber and a fiber. The short-wavelength-pass filter produces an intracavity laser pulse. The fiber has a length, and connects the short-wavelength-pass filter, the polarization controller and the optical gain fiber in series. The optical cavity has an anomalous dispersion range and a net group-velocity dispersion being within the anomalous dispersion range due to the length of the fiber. The optical cavity causes the intracavity laser pulse to propagate therein for providing the output laser pulse, providing a first laser pulse, a second laser pulse and a third laser pulse to the short-wavelength-pass filter, the polarization controller and the optical gain fiber respectively, and adjusting the intracavity laser pulse.

Wavelength or pulsewidth tunable mode-locked fiber laser system

The present invention provides a solar-pumped active device which utilizes a holographic antenna grating on a solar energy silicon substrate to select specific diffracted wavelength and couple pump wavelength in an approximately vertical way and converge the pump wavelength to excite an optical gain medium so that an optical amplifier or a laser can be obtained. The present invention requires no big size and is flexible over the surface shape and is suitable for free space optical communications on the ground and satellite optical communications. It means that the holographic antenna grating can be applied on the top floor of a building or on the glass surface of an outer wall. If it is applied to a satellite, the present invention can be deposited on a solar energy cell substrate to form a high optical amplification so that not only the electricity required in satellite optical communications can be reduced, but also a high-speed and large capacity of data can be transferred between satellites.

Solar-pumped active device

Solar-pumped laser

The present invention has a core and at least one cladding, where, by changing the temperature of the cladding, the material dispersion characteristic of the cladding is changed and a refractive index is varied to make fundamental-mode cutoff tunable as well; and the difference between dispersion slopes of core and cladding is crucial to the sharpness of the fundamental-mode cutoff.

Tunable fiber amplifier and laser

An optical amplifier and a laser generator based on the fiber side-polished technology having a high pumping efficiency, a low noise figure and a small footprint are provided in this application. The optical amplifier and the laser, which have a very long effective interaction length in conjunction with highly doped Erbium glass attached to its surface and an addition of a slanted fiber grating inscribed in the guiding core at the polished region can spatially separate the signal and pump power to simultaneously improve the pumping efficiency and optimize the penetrated depth of the signal evanescent-field. The spontaneous emission is kept from being amplified and therefore a high quality amplified signal is produced.

Evanescent-field optical amplifiers and lasers

An optical amplifier and a laser generator based on the fiber side-polished technology, having a high pumping efficiency, a low noise figure and a small footprint are provided in this application. The optical amplifier and the laser, which have a very long effective interaction length in conjunction with highly doped Erbium glass attached to its surface and an addition of a slanted fiber grating inscribed in the guiding core at the polished region can spatially separate the signal and pump power to simultaneously improve the pumping efficiency and optimize the penetrated depth of the signal evanescent-field. The spontaneous emission is kept from being amplified and therefore a high quality amplified signal is produced.

A wide-band fiber-optic tunable filter is provided. Dispersive polymers with different dispersion characteristics and side-polished fibers are used to fabricate wide-band tunable band-pass filters, band-rejection filters, short-wavelength-pass filters or long-wavelength-pass filters. This kind of wide-band fiber-optic tunable fiber filters is able to be used in the applications of fiber-to-the-home (FTTH) system networks. It is also able to be used in the applications of sensitive temperature sensors, high-resolution fiber refractometers, gain-flattened filters, fiber modal filters and fiber mode-field expanders/condensers.

Wide-band fiber-optic tunable filter

A fiber-optic tunable filter and an intensity modulator respectively includes: a fiber having a polished surface and an evanescent-field; and a photonic crystal having plural cavities and a filler filled therein and attached to the polished surface, wherein the plural cavities and the filler decide a photonic band-gap of the photonic crystal and the photonic band-gap is adjusted to reflect a light with a specific wavelength through the evanescent interaction with the photonic crystal material. Based on the fiber side-polishing technique, all kinds of fiber active and passive devices are able to be manufactured easily, especially for a high speed intensity modulator using an EO (Electro-Optic) polymer as the filler.

Fiber-optic tunable filter and intensity modulater

A manufacturing apparatus and method of a fiber coupler is provided. A movable electric arc is employed to fuse more than two stacked fibers for manufacturing a fiber coupler having a small size and good environment stability. It is advantageous that the fiber coupler can be used in a SDH (Synchronous Digital Hierarchy) communication system, and the method also be used to manufacture the all-fiber CWDM (Coarse Wavelength Division Multiplexing) multiplexer which covers the E-band wavelengths and the sub-components of the OADM (Optical Add/Drop Multiplexer). And, all these functions are difficult to be achieved by the conventional techniques.

Growing community of inventors

Miaoli, Taiwan

Nan-Kuang Chen