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The reason of pulse amplitude unequalization at repetition rate multiplying via Fabry-Perot (F-P) filter is analyzed. Several original methods of suppressing the amplitude unequalization are proposed. Their suppressing effects and tolerance to the F-P instability are compared and investigated.

A time-interweaved sampling scheme for optical A/D conversion is proposed, and to demonstrate this technique 2.5 GHz sine microwave signal is sampled at a rate of 16×2.5 GHz. 29dB signal-to-noise rate is acquired after processing the experimental data. In this paper we analyse the impacts of the imperfect optical sampling pulses, including the waveform, pulse width, and time jitter, and then discuss the way to improve the sampling precision.

Detuning characteristics of the AM mode-locked fiber laser are studied both in analytic theory and numeric simulation. The analytic expression of the locking range is given and is additionally verified by the numeric study. Both the two theories reveal that the pulse width remains as a constant and the pulse position varies linearly versus the detuning, when the detuning is small enough. The laser characteristics both inside and outside the locking range are examined in detail.

Some characteristics of supercontinuum generation in the dispersion-shifted-fiber are studied both in theory and experiment. The theoretical research shows how the fiber nonlinearities, such as self-phase-modulation, four-wave-mixing and cross-phase-modulation, play their roles in the supercontinuum generation. Some dependent parameters of supercontinuum generation, such as the fiber length, the pump power are also discussed in this paper. The experimental results agree well with the theoretical simulations.

In this paper, the theoretical model of the UNI is proposed in detail, which counts on the ultrafast nonlinearities and longitudinal effects of semiconductor optical amplifier (SOA). The transfer function of UNI is also obtained. The switching window, which is a key parameter for demultiplexer, is then analyzed. It's shown that the switching window properties are determined by the length of SOA, the length of the birefringence fiber (BRF), and the parameters of control pulses such as control pulse energy, pulsewidth, power.

The time-domain ABCD matrix formalism is based on the propagation of a Gaussian pulse which is characterized by the pulsewidth and chirp. In this paper, we will perfect this method and derive time-domain ABCD matrices for more optical devices. Especially, we extend this perfected theory to analyze the principle of passive mode-locking by reasonable approximation though, as we know, the output pulse generated from passive mode-locking fiber laser is of sech-shape. It is attractive because it can present a fairly apparent view to understand the mechanism of fiber lasers as well as analytic results to understand the pulse characteristics.

Without any stabilization equipment, multiwavelength laser oscillation was obtained in Erbium-doped fiber laser, basing on a section of standard multimode optical fiber which was twined as a polarization controller (PC). The number of lasing wavelength and wavelength spaces can be controlled by changing the state of PC.

In this paper, the properties of the optical phase-locked loop(PLL) based on the four-wave mixing in the semiconductor laser amplifiers (SLAs) are discussed. The components that achieve the function of detecting the bit phase of the input optical signal are concerned and discussed in detail together as a function module named as the optical bit phase detector referred to the general electronic PLL. Therefore, most of the properties of the optical PLL can be analyzed by applying the general phase-locked theory. Here the stability of the optical PLL is discussed. It's shown that the variance of input signal power in the practical application will cause optical PLL system unstable because of its long loop delay. The influence on the output phase jitter of the optical PLL is also investigated.