高速调制光光折变自适应光外差探测系统实验研究

利用新型光折变自适应光外差探测系统，对相位畸变的高速振幅调制信号进行了光外差探测实验研究。获得了稳定的光外差输出．实验研究表明，提高本振光强度可提高光外差输出信号强度，所以该系统适用于对弱信号的探测；同时新型系统对高速振幅调制信号光有更高的探测灵敏度．因此，这种新型光折变自适应光外差探测系统可应用于空间相位畸变的时域高速调制弱信号光的外差探测．     

一种新型的光折变自适应光外差探测系统

通过研究光折变晶体内处泵浦与互泵浦相位共轭共存的特性，提出了一种新型的光折就自适应的光外差探测系统。与现有的光折变自适应光外差探测系统相比，该系统仅采用一块光折变晶体就能很好地实现自适应光外差探测，具有结构简单、易调整等特点，利用Ar^ 激光实验证实了系统在实际应用中的可行性，可观察到中频外差输出信号。     

调制电势脉冲型O2／CO2双组份电化学气体传感器研究

基于直接电流法检测ＣＯ２及Ｏ２干扰机理的研究,提出了调制电势脉冲－电流／库仑法快速同时测定Ｏ２和ＣＯ２的新原理,使用微电极并融合计算机控制的快速电势调制技术,建立了调制电势脉冲型Ｏ２／ＣＯ２双组份电化学气体传感器的原型装置,实现了常温下Ｏ２和ＣＯ２气体的快速同时检测。     

高速调制光束的互泵浦相位共轭器的研究

利用光折变晶体中高速振幅调制光束的简并四波混频（ＤＦＶＶＭ）理论和互泵浦相位共轭器（ＭＰＰＣ）的两作用区模型，对高速振幅调制光束的ＭＰＰＣ进行研究，给出了ＭＰＰＣ的共轭反射率、透过率以及作用区中光扇开系数的表示式及数值结果．实验上所得到的互泵浦相位共轭光的规律与理论相吻合．     

Compressive behavior and energy absorption of metal porous polymer composite with interpenetrating network structure

Interpenetrating phase composites （IPCs） are a new class of composite materials with improved combinations of mechanical and physical properties. This study was performed on a new type of IPC called metal porous polymer composite （MPPC） with an interpenetrating network structure. Aluminum-polypropylene （Al-PE） and Aluminum-epoxy resin （Al-Ep） composites were produced by infiltrating the polymer in the aluminum foam. The composite microstructures were characterized using SEM observation. The compressive behavior and energy absorption characteristics of MPPC were investigated and compared with the aluminum foams. The compressive modulus of composite was compared with the VOIGT-REUSS bounds and HASHIN-SHTRIKMAN （H-S） bounds models. The experimental modulus of compressive tests falls well within the theoretical models.     

基于MPPC阵列探测器的激光测距系统与试验

将4×4多像素光子计数器(MPPC)阵列作为回波 探测器,利用云南天文台升级后的1.2m望远 镜分光路卫星激光测距(SLR)系统,开展了地面漫反射靶和AJISAI卫星的SLR试验。地面靶目 标是60cm的 Al塑板,光程约为45m,用示波器采集单通道输出信号与16通道合并 输出信号,合并输出信号幅值明 显高于单通道输出信号,表明不止一个通道有响应;用事件计时器记录主波、回波时刻并进 行距离解算, 其RMS约为21.7cm,与激光脉冲宽度、漫 反射目标的形状效应引起的测距误差相当。实验结果表明,阵列型探测器较单 元型有一定优势,实验中采用的MPPC阵列探测器进行性能升级后可用于SLR。     

Beam tests of directly coupled scintillator tiles with MPPC readout

We report on the response to a proton beam of scintillator tiles directly coupled at the face of the tile to multi-pixel photon counters. Detailed measurements with protons show that flat tiles have high response near the photon counters while concave tiles have uniform response suggesting that tiles with this versatile configuration can be tailored to a desired uniformity. The beam response is in qualitative agreement with the response to a non-triggered radioactive source and reveals additional spatial features.     

The statistical properties of continuous wave photon counting based on a multi-pixel photon counter (MPPC)

Second and third order statistics are presented for continuous injected photons counted with a multi-pixel photon counter (MPPC). The number of thermal modes, μ, for the pseudo-thermal light has been acquired under different rotation velocity of the ground glass. At the same time, the MPPC detector's gain coefficient, γ, and cross-talk probability, ε, were achieved through theoretical curve fitting. Finally, we have given an analysis for the saturation effects of the MPPC under continuous injected photons. The results showed that the MPPC model is consistent with the experimental measurement while the photon counting rate was lower than 1200?kcps (threshold), but had larger differences while the photon counting rate was higher than this threshold.     

SIPM在脉冲光检测系统中的应用研究

为了实现硅光电倍增管(silicon photomultiplier,SIPM)对超出光子计数极限的微弱脉冲光信号的测量,建立了基于SIPM积分工作模式的脉冲光检测系统。测试了SIPM在同一光信号照射下,偏置电压与增益以及信噪比之间的关系,并测试了同一增益条件下,SIPM对不同光信号的响应特性。结果表明:SIPM在积分工作模式下,其增益可以达到104以上,并随着偏置电压的增加而指数增长;其信噪比也随着电压的增加而增加,在光强比较微弱的情况下,SIPM对光强是线性响应的。所设计的系统可以在一定程度上替代光电倍增管进行微弱脉冲光信号的测量。