• Journal of the Institute of Convergence Signal Processing
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• v.22 no.3
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• pp.104-109
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• 2021

In this paper, we experimentally demonstrate a self-seeding FP-LD (Fabry Perot Laser Diode) to verify the possibility of a new tunable light source that can be used in WDM-PON (Wavelength Division Multiplexing - Passive Optical Network) system. The conventional implementation of WDM-PON using a tunable light source has a disadvantage that the center wavelength of the AWG (Arrayed Waveguide Grating) device and the tunable light source must be precisely aligned. However, the proposed tunable light source has the advantage that the tunable wavelength is automatically aligned with the center wavelength of the AWG as well as simple structure. The implemented tunable light source had a tunable band of about 14 nm or more, and the maximum RIN (Relative Intensity Noise) of about -124 dB/Hz, which showed the possibility of modulating 10 Gb/s signal by an external modulator.

• Journal of the Optical Society of Korea
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• v.9 no.2
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• pp.45-48
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• 2005

We investigate effects of the injected ASE (Amplified spontaneous emission) bandwidth on the performance of the wavelength-locked Fabry-Perot laser diodes (F-P LDs) under constant injection power density and constant injection power. For the constant injection power density, we can determine the minimum injection bandwidth by the required intensity noise or the bit-error rate (BER) performance. On the other hand, there exists the optimal ASE bandwidth for the constant injection power to minimize the intensity noise.

• Journal of the Optical Society of Korea
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• v.16 no.2
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• pp.101-106
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• 2012

We demonstrate a cost effective broadcast signal transmission at 1.25-Gb/s with 100 GHz channel spacing based on a broadband light source (BLS) for a wavelength division multiplexing-passive optical network (WDM-PON). The BLS is implemented by using mutually injected Fabry-Perot laser diodes (MI F-P LDs). The error-free transmission without a forward error correction (FEC) is achieved by its low relative intensity noise (RIN). The number of usable modes is determined by RIN and/or extinction ratio (ER) in the spectrum sliced light output.

• Journal of the Optical Society of Korea
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• v.9 no.3
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• pp.103-106
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• 2005

Recently, polymethyl methacrylate based plastic optical fibers (POFs) have attracted considerable attention as a potential medium for local area network (LAN) and home network applications. Since the POFs have very low optical loss at around 650mm, in particular, it becomes quite important to develop GHz transmitters operating at this wavelength for high bit rate optical transmission applications of the POFs. In this paper, we present generation of ${\geq}1.5 Gbps$ pseudo-random binary sequence optical signals by using a gain switched InGaA1P Fabry-Perot semiconductor laser with a high frequency filter, operating at 650mm, and the application of these signals to bandwidth measurement of POFs.

• Korean Journal of Optics and Photonics
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• v.1 no.2
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• pp.178-184
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• 1990

The fiber laser was fabricated using Nd doped single mode fiber. The fiber was made by MCVD and solution doping method, and the Fabry-Perot resonator was composed with two dichroic mirrors. It was operated at 1.096 um with 15 nm bandwidth. When the reflectivity of the output copuling mirror was 67.5%. the maxiurn output power 1.88 mw and its slope efficiency 1.28%. was obtained.

• Journal of the Optical Society of Korea
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• v.8 no.4
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• pp.163-167
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• 2004

We propose and demonstrate an external optical modulation method based on TE/TM-mode absorption nulls in a Multiple Quantum Well(MQW) Fabry-Perot laser diode(FP-LD). The center wavelength of the absorption nulls is rapidly shifted to short-wavelength by the small current change(~1mA) in the FP-LD, which can modulate an optical signal with more than 10 dB of extinction ratio(ER). The shift of the center wavelength comes from the refractive index change due to anomalous dispersion and the plasma effect in MQW FP-LD waveguide. Non-inverting and inverting signals are made by TE- and TM-mode absorption nulls at 155.52 Mbps and BERs for the signals are measured.

• Proceedings of the Optical Society of Korea Conference
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• 2005.02a
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• pp.112-113
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• 2005

• Proceedings of the Optical Society of Korea Conference
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• 1997.08a
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• pp.75-75
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• 1997

• Korean Journal of Optics and Photonics
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• v.8 no.1
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• pp.68-72
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• 1997

Using one of the absorption lines of $^{13}C_2H_2$ molecules near the zero dispersion wavelength(1549.49nm) of dispersion shifted fiber, we stabilized center frequency of an optical fiber Fabry-Perot filter. The free spectral range of the filter is 100 GHz for 100 GHz channel allocation. For equi-spaced three channel multiplexing, channel locking of three DFB-LDs to transmission peaks of the fiber Fabry-Perot filter was tried. To investigate the effect of dithering current applied to each DFB-LD, the change of DFB-LD linewidth was measured.

• Korean Journal of Optics and Photonics
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• v.15 no.1
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• pp.34-38
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• 2004

A fiber laser of which wavelength was scanned by an intra-cavity FP (Fabry-Perot) filter was used to interrogate a fiber Bragg grating strain sensor array. We calculated the wavelength variation of the fiber laser using quadrature signal processing with an unbalanced M/Z (Mach-Zehnder) interferometer and time-delayed sampling technique. The calculated wavelengths are mapped to corresponding temporal reflection peaks from the sensor array, which enables more accurate and stable interrogation without the problems caused by the FP filter's nonlinear characteristics. Wavelength resolution of ∼20 pm was obtained in our experimental setup, which could have been greatly enhanced with faster phase modulation.