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A structure of optical arbitrary waveform generation (OAWG) based on an array of tunable apodized waveguide Bragg gratings (WBGs) is proposed. The WBGs array on lithium niobate (LN) consists of several apodized gratings, waveguides and electrodes deposited on both sides of gratings and waveguides. The properties of OAWG are analyzed using transfer matrix method. Due to the electro-optic effect of LN, the amplitude and phase of incident light source are controlled via adjusting the voltages on electrodes. Consequently, the optical pulses with different waveforms are obtained and the amplitude is linearly tuned. In addition, voltages compensating amplitude and phase distortion are demonstrated.

A multi-wavelength tunable filter is designed. It consists of multiple waveguides among multiple waveguide gratings. A pair of electrodes were placed on both sides of each waveguide. The tunable filter uses the electro-optic effect of Lithium Niobate to tune the phase caused by each waveguide. Consequently, the wavelength and wavelength spacing of the filter are tuned by changing external voltages added on the electrode pairs. The tunable property of the filter is analyzed by phase matching condition and transfer-matrix method. Numerical results show that not only multiple wavelengths with narrow bandwidth are tuned with nearly equal spacing by synchronously changing the voltages added on all electrode pairs, but also the number of wavelengths is determined by the number of phase shifts caused by electrode pairs. Furthermore, due to the electro-optic effect of Lithium Niobate, the tuning speed of the filter can reach the order of ns.

An optical modulation format generation scheme based on spectral filtering and frequency-to-time mapping is experimentally demonstrated. Many modulation formats with continuously adjustable duty radio and bit rate can be formed by changing the dispersion of dispersion element and the bandwidth of shaped spectrum in this scheme. In the experiment, non-return-to-zero (NRZ) signal with bit rate of 29.41 Gbit/s and 1/2 duty ratio return-to-zero (RZ) signal with bit rate of 13.51 Gbit/s are obtained. The maximum bit rate of modulation format signal is also analyzed.

This work deals with the variation of urinary metabolite of patients suffering from premenstrual syndrome (PMS) and the function of Jingqianping granules (JG) in intervening liver-Qi invasion by metabonomic. The metabonomic characteristics and the micromolecular marking compound, which are closely related to the pathogenesis of PMS liver-Qi invasion cases, are also investigated. PMS liver-Qi invasion cases are calibrated according to the diagnostic criteria, including criteria, and excluding criteria. The urine samples from PMS liver-Qi invasion patients are analyzed at different times using UPLC-Q-TOF in combination with PCA pattern analysis, followed by discrimination of the metabolic outline and searching for the possible biological tags and metabolic pathways. The metabolic outline of premenstrual urine samples has significant difference among the control group, the PMS liver-Qi invasion group, and the PMS liver-Qi invasion treatment group. The metabolic outline of premenstrual urine sample of the PMS liver-Qi invasion group diverges from the premenstrual and postmenstrual urine samples of the control group and the postmenstrual urine sample of the PMS liver-Qi invasion group. Compared with the control group, N-acetyl-2-glutamate-5-semialdehyde has decreased greatly in the N-acetyl-2-glutamate-5-semialdehyde liver-Qi invasion group, and histidine and 3-methoxy-4-hydroxymandelaldehyde have increased significantly. This research, for the first time, deals with the metabolic pattern differences between the control group and the administration group. It shows that JG may repair metabolic disturbance of endogenous micromolecules in PMS liver-Qi invasion cases in terms of metabonomics. It also demonstrates that symptoms present before menstruation in PMS patients and the characteristic of PMS is that the symptoms appear before menstruation and disappear after it among PMS liver-Qi invasion cases.

A width-tunable pulse laser via an optical injection induced gain modulation of a semiconductor optical amplifier (SOA) is demonstrated. When the pump current of the SOA is 330 mA or 400 mA and a continuous wave is injected into the laser cavity with different powers, bright or dark pulses with different pulse widths and frequency repetition rates are obtained. The bright and dark pulses are formed by the effect of gain dispersion and cross-gain modulation of the SOA.