| 1. | Direct measurement of ch4 absorption spectrometer by means of tunable frequency modulated diode laser
激光频率调制光谱法测量甲烷的吸收光谱 |
| 2. | Utilizing quasi - phasematched ( qpm ) technique to achieve a given useful laser frequency conversion is a practical and challenging topic
利用准相位匹配( qpm )技术在光学超晶格中实现特定的可实用化的激光频率变换，在目前是一个富有实际意义和挑战性的课题。 |
| 3. | This paper describes the important breakthrough of laser frequency measurements technology since 1999 , i . e . the absolute frequency value of laser frequency standards can be directly measured by femtosecond modelocked laser
摘要简述了自1999年以来激光频率测量技术出现的重大突破，用飞秒锁模激光可以直接测量激光频标的绝对频率值。 |
| 4. | It presents the mathematical models for the ppm modulation and demodulation circuits system . author gives out the conditions of linear modulation and demodulation , and educes its connection between the modulation factor and maximal laser frequency excursion
建立了ppm调制与解调的数学模型，给出了实现线性调制与解调的条件以及调制深度与最大激光频率偏移之间的关系。 |
| 5. | The main works and results we have accomplished are as follows : 1 ) red - detuned locking of cooling / trapping laser to the cycling transition of cesium cooling has been accomplished by means of a double - passed acoustic - optical frequency shifting system and the technique of saturated absorption spectroscopy . the short - term residual frequency jitter is less than 350khz ; 2 ) automatic controlling system by computer programs has been established for laser cooling and trapping and cavity qed experiment . the laser and magnetic fields can be controlled by the acoustic - optical modulator and the electronic - controlled logic gate respectively
具体如下： 1 )采用了往返两次通过的声光频移系统结合饱和吸收光谱技术的实验方案，实现了冷却俘获激光频率相对于铯原子冷却循环跃迁的负失谐锁定，短期频率稳定度约在350khz以内，并可方便地调节其负失谐量而无须对后续光路再作调整； 2 )建立了一套基于计算机程序控制的、铯原子激光冷却与俘获实验所需的时序控制系统。 |
| 6. | 4 . the theory of cavity enhanced absorption spectroscopy is studied in detail and the numerical simulation is firstly demonstrated . in addition , we analyze the variation of sensitivity and linearity of this technique with the scan speed of incident light frequency or absorption cavity length
深入研究了腔内增强吸收光谱的理论，首次给出了具体的解析表达形式及数值模拟计算结果，分析了腔内增强吸收光谱测量的灵敏度、线性度与激光频率扫描速度、吸收腔长改变速度的关系。 |
| 7. | Because p - si is of more special characteristics , comparing to a - si and c - si , firstly , i set forth electrical features of p - si film and acknowledge profoundly electrical mechanism of p - si film . then three parameters of laser annealing , including laser frequency - , accepted - pulse - times and laser power density are studied how to influence crystallization of p - si
因为多晶硅和非晶硅及晶体硅相比具有更独特的特点，所以我们先阐述了多晶硅薄膜的电学特点，对多晶硅的导电机理有了深刻的了解；然后研究了激光频率、受光次数和激光功率密度三个参数对晶化多晶硅的影响。 |
| 8. | The definition of stability and repeatability of the laser frequency and factors affecting the stability of laser frequency were analysed . the normal methods used to stabilise frequency and produce double - frequency were explained . after analysing the working conditions and related parameters of the laser device , it was concluded that the laser tube should be put inside an insulating cover and an electric discharge tube with a bigger diameter and length , smaller wall thickness and a higher thermal conductivity coefficient should be chosen
分析了激光频率的稳定性、复现性的定义及影响激光频率稳定的因素；介绍了常见的稳频及产生双频的方法；分析论证了激光器双纵模热稳频的使用条件和有关参数的关系，得到结论是：应将激光管装在保温罩内；选用放电管直径及长度大、壁厚小、材料导热系数大的放电管。 |
