摘要
从三维射线方程出发,经过分析和简化,得到水平非均匀大气条件下射线描迹的微分方程组,作为光学测量的理论基础。分析了温度梯度分布的一般特征;在射线弯曲的几何关系基础上,分析了折射角及折射角变化量和温度梯度的积分关系,讨论了路径加权特性,表明在非均匀并且温度梯度对光路中心不对称分布条件下,单边光学测量得不到温度梯度的区域平均值。需要通过双向对测,才能得到光路上温度梯度的算术平均。同时表明,多光源测量系统在非均匀大气近地面层得不到准确的平均温度廓线。
Equations are obtained which describe the trajectory of light ray through the unhomogeneous atmospheric surface layer when the three-dimensional equation of ray is analyzed and simplified.The equations can be used as the base of optical measurement.Characteristics of temperature gradient in the surface layer are discussed.The integral which relates the refraction angle and its variable to the temperature gradient based on the geometry of ray curve and the weighting function of temperature gradient are discussed.It was shown that the area-averaged value can not be obtained by means of unilateral measurement of angle when the distribution of temperature gradient is unhomogeneous and symmetrical.A bidirectional optical system is necessary.It was shown that the area-averaged temperature profile also can not be obtained by means of a system with multi-laser sources in the unhomogeneous atmospheric surface layer.
出处
《大气与环境光学学报》
CAS
2009年第1期1-7,共7页
Journal of Atmospheric and Environmental Optics
关键词
折射
温度梯度
大气近地面层
非均匀
refraction
temperature gradient
atmospheric surface layer
unhomogeneous
作者简介
曾宗泳(1940-),男,汉族,四川南充人,研究员,学士,研究方向为大气湍流和大气光学.E-mail:zyzeng@aiofm.ac.cn
