Browsing by Author "Sien"

Now showing 1 - 17 of 17

All-optical 2R regenerator using self-seeded laser diode
(2009-04-14)
Chi
;
Sien
;
Lee
;
Chien-Chung
;
Chien
The present invention is a self-seeded laser diode. The laser diode obtains a gain by itself without using expansive erbium-doped fiber amplifiers. Hence, the cost is reduced and the system is simplified.
Evanescent-field optical amplifiers and lasers
(2007-02-27)
Chen
;
Nan-Kuang
;
Chi
;
Sien
;
Tseng
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
(2007-01-30)
Chen
;
Nan-Kuang
;
Chi
;
Sien
;
Tseng
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.
Fast wavelength-tunable laser system using Fabry-Perot laser diode
(2006-04-11)
Chi
;
Sien
;
Lee
;
Chien-Chung
;
Yeh
The invention relates to a laser system using a multi-longitudinal-mode Fabry-Perot laser diode as an inter-injection light source and a gain cavity formed by other laser diodes of such type so as to achieve the function of fast wavelength switching, so that it is possible to achieve repetitively fast switching of wavelength by varying and controlling the bias voltage of maximum optical gain in said inter-injection type multi-longitudinal-mode Fabry-Perot laser diode so as to achieve three different wavelengths with tuning range of 3.5 nm for a side-mode suppression ratio (SMSR) greater than 19 dB and a response time of wavelength switching in the order of nanosecond.
Fiber bragg grating sensor system
(2003-11-11)
Chi
;
Sien
;
Tseng
;
Hong-Yih
;
Peng
The present invention provides a fiber Bragg grating system, which employs a linear-cavity fiber laser scheme to develop a high resolution sensor system. The fiber Bragg grating sensor device is located in one end for fiber laser reflecting, and in the other end is a fiber loop mirror. It forms a linear-cavity fiber laser scheme basis. The end for laser output parallel connecting with two fiber Bragg grating filters. Because of the spectrum shift of the fiber Bragg grating sensor when temperature changed, it may detect the optic power reflectivity for the variation of the temperature. Furthermore, it can resolve the temperature up to 10.sup.-4.degree. C. theoretically and can be applied for strain and temperature sensing with high precision.
Fiber sensing system with self-detection mechanism
(2011-04-12)
Chow
;
Chi-Wai
;
Chi
;
Sien
;
Wang
The present invention discloses a fiber sensing system with self-detection mechanism which utilizes a central office to control secondary ring architecture formed by fiber sensor, remote node and optical coupler primarily. The secondary ring architecture is connected serially to form a primary ring architecture. The central office has a tunable laser light source that can deliver the light source to the fiber sensor. Since the fiber sensor has reflective ability, all light source signal sent by the tunable laser light source will be detected and measured by the fiber sensor. Thus central office can detect all signals reflected by the fiber sensor and produce a spectrum for analyzing fault point locations. The present invention can greatly enhance survivability and sensing capacity of all fiber sensors, so that when a fault point caused by environmental change within the fiber, it will not effect the overall operation of the sensing mechanism. The application of fiber sensor can also reduce cost and complexity of the overall fiber network topology.
Fiber-optic tunable filter and intensity modulater
(2006-04-04)
Chen
;
Nan-Kuang
;
Chi
;
Sien
;
Tseng
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.
Manufacturing method and apparatus of fiber coupler
(2006-02-07)
Chi
;
Sien
;
Tseng
;
Shiao-Min
;
Chen
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.
Method of enhancing spatial resolution for distributed temperature measurement
(2004-11-16)
Chi
;
Sien
;
Lee
;
Chien-Chung
;
Chiang
A method that utilizes a short sampling interval and a long-pulsewidth laser source to obtain the long sensing range and employs a signal processing technique of decomposing Brillouin spectrum to achieve high spatial resolution, high temperature resolution of the distributed temperature measurement is disclosed. The present method includes the steps of measuring the Brillouin spectra of an optical pulse applying to a sensing fiber and a overlapped area thereof, determining the length that the pulse enters according to the measured Brillouin spectra and a weighting factor and then determining a real Brillouin spectrum profile and a temperature distribution according to Brillouin frequency shifts thereof. For a 9500-m sensing range of standard single-mode fiber and a 100-ns pulsewidth laser source, spatial and positon resolutions of 20 cm and a temperature resolution of 1.degree. C. are simultaneously achieved by using this signal processing method.
Method of utilizing a fiber for simultaneously measuring distributed strain and temperature
(2004-03-02)
Chi
;
Sien
;
Lee
;
Chien-Chung
;
Chiang
A method that utilizes a dispersion-shifted fiber having compound compositions with different temperature coefficients in core to simultaneously measure the distributed strain and temperature based on Brillouin frequency shift is disclosed. The present method includes the steps of obtaining mean two peak frequencies in a multi-peak Brillouin spectrum of the dispersion-shifted fiber, determining a temperature change according to the formula of a Brillouin frequency shift of the peak relating to strain and temperature conditions of the fiber, and determining a strain change through the formula. In a 3682-m sensing length of Large-Effective-Area NZ-DS fiber, a temperature resolution of 5.degree. C., a strain resolution of 60 .mu..epsilon. and a spatial resolution of 2 m are achieve simultaneously.
Optical monitoring apparatus for use in wavelength division multiplexing network
(2006-03-07)
Chi
;
Sien
;
Lee
;
Chien-Chung
;
Yeh
An optical monitoring apparatus based on the scanning of the gain profile of erbium-doped fiber amplifiers (EDFA) and applied in a wavelength division multiplexing network has been proposed and experimentally demonstrated. The EDFA with an injected saturated tone can provide variable gain or loss profile by controlling the pump power. The components used in the present optical monitoring apparatus for use in a wavelength division multiplexing network are easily available and cost-effective, valuable for monitoring frequency and power of a WDM optical communication system, and capable of greatly enhancing resolution of monitoring frequency spectrum for the optical fiber network system.
Self-healing fiber Bragg grating sensor system
(2006-05-09)
Chi
;
Sien
;
Peng
;
Peng-Chun
;
Lin
The present invention is a self-healing fiber Bragg grating sensor system which comprises a central office, at least one network node, at least one 2×2 optical switch and at least one fiber Bragg grating. The network node can be made of optical switch. When the fiber for the sensor system is broken, sensing signals are discriminated in different paths provided by the network nodes to avoid stop working once the fiber is broken, by which the self-healing ability of the system is greatly improved. Besides, by using the structure of fiber laser in the present invention, the power output and the signal-to-noise ratio can be greatly increased. Accordingly, the present invention is to design a fiber sensor system with low cost and high capacity and with capability of self-healing.
Solar-pumped active device
(2008-08-26)
Chi
;
Sien
;
Chen
;
Nan-Kuang
;
Shy
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 laser
(2008-07-22)
Chi
;
Sien
;
Chen
;
Nan-Kuang
;
Shy
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.
Tunable fiber amplifier and laser
(2008-04-29)
Chi
;
Sien
;
Chen
;
Nan-Kuang
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.
Using intensity and wavelength division multiplexing for fiber Bragg grating sensor system
(2005-04-12)
Chi
;
Sien
;
Tseng
;
Hong-Yih
;
Peng
The present invention provides a fiber Bragg grating sensor system, which comprises a light-division device having receiving-sending terminals and sensing terminals, a light generating device and a photo detector coupled with receiving-sending terminal of a light-division device, sensing fibers coupled with the sensing terminals, said sensing fiber comprising a fiber Bragg grating, a information processor connecting with said photo detector. The light-division device distribute different optical energy ratio from said receiving-sending terminals to said sensing terminals. The intensity and wavelength division multiplexing can make different intensity for the information addressed of different sensing fiber on the same optical channel to enhance the sensing capacity of fiber Bragg grating sensor system.
Wide-band fiber-optic tunable filter
(2006-12-26)
Chi
;
Sien
;
Chen
;
Nan-Kuang
;
Tseng
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.