Ming-Ching Lin

Fiber Bragg Grating-Based Multiplexed Sensing System Employing Fiber Laser Scheme with Semiconductor Optical Amplifier

We propose and demonstrate experimentally a multipoint fiber Bragg grating (FBG) sensor system, based on fiber Bragg gratings (FBGs), using a semiconductor optical amplifier (SOA) as a gain medium. Multiple wavelength operation is based on the inhomogeneous broadening effect of the SOA of the sensing system. In addition, the behavior of the proposed sensor configuration is also studied.

Stabilized and wavelength-tunable S-Band erbium-doped fiber ring laser with single-longitudinal-mode operation.

A stable and wavelength-tunable S-band erbium-doped fiber (EDF) ring laser with single-longitudinal-mode oscillation over the operating range of 1480.6 to 1522.9 nm is proposed and experimentally demonstrated. The proposed ring laser provides a fine mode restriction and guarantees the single-frequency operation based on a shorter length EDF serving as auto-tracking filter. Therefore, the performances of output power of > 10 dBm, power stability of < 0.05 dB, central wavelength variation of <0.01 nm, and side-mode suppression ratio (SMSR) of > 49.1 dB have been experimentally demonstrated in the operating range of 1488.7 to 1505.7 nm.

A tunable erbium-doped fiber ring laser with power-equalized output.

We propose and demonstrate a tunable erbium-based fiber ring laser with power-equalized output. When a mode-restricting intracavity fiber Fabry-Perot tunable filter (FFP-TF) is combined, the proposed resonator can guarantee a tunable laser oscillation. This proposed laser can obtain the flatter lasing wavelength in an effectively operating range of 1533.3 to 1574.6 nm without any other operating mechanism. Moreover, the performances of the output power, wavelength tuning range, and side-mode suppression ratio (SMSR) were studied.

Simultaneously gain-flattened and gain-clamped erbium fiber amplifier

In this paper, we propose and demonstrate a simple erbium amplifier module based on an erbium-doped fiber amplifier (EDFA) and an erbium-doped waveguide amplifier (EDWA) in serial, having gain-flatted (GF) and gain-clamped (GC) functions simultaneously. In first proposed GF amplifier scheme, the maximum gain variation of 2.5 dB can be observed in the effective range of 1528 to 1562 nm and the entire gains are above 35 dB with the input signal power of −30 dBm. Hence, we investigate second scheme by optical feedback method in the proposed fiber amplifier achieving gain-flattened (GF) and gain-clamped (GC) efficiencies simultaneously. Thus, the maximum gain variations of ±0.8 and ±1.8 dB can be obtained in the operating range of 1530 to 1564 nm, when the input signal powers are −16 and −40 dBm, respectively. Moreover, the dynamic gain profile can be adjusted and dynamic input power range is also measured based on the proposed GF and GC fiber amplifier.

Stable single-longitudinal-mode grating-based S-band erbium-doped fiber laser

We propose and demonstrate a single-longitudinal-mode (SLM) grating-based erbium fiber laser with a passive multiple-ring cavity structure in S-band operation. The laser is fundamentally structured by adding three different short ring cavities, which serve as the mode filters, into a major ring cavity. When an S-band mode-restricting intracavity fiber Bragg grating is combined, the proposed resonator can guarantee a SLM laser oscillation. Proposed fiber laser effectively suppresses the side-mode frequencies of 1 GHz and provides an output power of 0.1 dBm with a side-mode suppression ratio (SMSR) of 48.6 dB at 1513.35 nm.

Long-distance strain-induced-grating-based fiber sensors with erbium-based amplifiers

We investigate and demonstrate experimentally a two-stage erbium-based amplifier with a larger amplified-spontaneous-emission light source for a long-distance fiber sensor by using strain-induced fiber Bragg gratings in the fiber systems. In a 20-km-long fiber sensor system, the sensor has a maximal ≈ 2.28-nm wavelength shift under a 1500-μm/m strain.

S-band gain-clamped grating-based erbium-doped fiber amplifier by forward optical feedback technique

An S-band gain-clamped erbium-doped fiber amplifier module, employing a fiber Bragg grating to serve as a reflected element for lasing a saturated tone injected into the module by forward optical feedback method, is proposed and investigated experimentally. Moreover, the performance and behavior of the gain and noise figure in the proposed gain-clamped S-band fiber amplifier have also been discussed in the effectively wavelength range of 1478 to 1520 nm.