The Study Of Dual-beam Amplification Of Brillouin Scatting In Single Cell

At present, because of the high resolution of detection accuracy and detection resolution, Brillouin scattering techniques are used widely. In the technology, the signal of light which it detected has become very weak by water attenuation, and it is difficult to be detected by detector. People proposes a method to enlarge the signal light of Brillouin scattering , which is a two-cell Brillouin scattering amplification technology. the technology can effectively improve intensity of the Brillouin scattering signal. However, the device is too complex to adapt the practical environment.A new Brillouin amplification technology is presented in this paper: dual-beam Brillouin scattering amplification technology in single-pool. The technology can enhance intensity of the signal light, and also can guarantee the quality of the signal light. The amplification technique using two beams of coherent light pulse to make Brillouin amplification. In this method, one of pulse t is used to generate stimulated Brillouin scattering in water, and the other is used for amplify the SBS signal light. We can get a higher signal intensity of Brillouin light, and it can avoid the high-energy laser producing other non-linear process in water.On the study of dual beam amplification of Brillouin scattering in single-cell, this paper made the following work: 1) Using two pulse lasers obtain two beams pulse which meet the requirements of the program. The two beams of light are coaxial, with same polarization and phase and frequency and pulse width. 2) Design and build a double-beam Brillouin scattering amplification experimental, realized the thinking of SBS signal amplification. This paper analysis the experimental results comparative to which of single-beam Brillouin scattering. 3) Though theoretical analysis and experimental validation we have know that double-beam angle effect the amplification efficiency : Under certain energy ratio,SBS gain coefficient decreases with increasing the angle. But in the range of 0～2mrad of the double-beam angle , the relatively small changes.4) Study the amplification efficiency about polarization of double-beam on the amplification system. Get a best enlarge polarization angle about 10 degree. 5) Improved signal reception system, Joined a cylindrical lens in the system.According to the theoretical results and experimental analysis, we know the technology which this paper discussed is Superior than the traditional laser detection technology .its can reduce the nonlinear processes of the high-energy pulse . The nonlinear processes will cost laser energy when it produces in the water .so the method can improve the signal-noise ratio and the intensity of signal light.