光谱色散匀滑对焦斑光强频谱的影响

基于焦斑光强的空间频谱分析方法，建立了光谱色散匀滑技术（SSD）对焦斑匀滑的影响模型，提出了控制焦斑空间频率调制的响应函数.揭示了SSD参量对空间频率响应函数的影响规律.理论推导和数值模拟结果都表明：SSD对焦斑光强的频率响应具有周期调制性质，调制特性和色散角、光谱形状等相关.一般地，光谱形状控制空间响应函数形状，色散角决定所能匀滑的最低频率，色循环数可改变响应函数特点，调整对空间低频和高频的匀滑效果.空间频率响应函数的特点为多维SSD应用提出了应用准则. 关键词： 光谱色散匀滑 空间频谱 焦斑 响应函数

Effect of smoothing by spectral dispersion on the spatial spectrum of focal spot

The model of laser spectrum used in the method of smoothing by spectral dispersion （SSD） affecting the beam smoothing was theoretically discussed based on the analysis of spatial frequency spectrum, and the response function to the spatial frequency modulation was put forward to describe the effects. With theoretical derivation and numerical simulation, it is concluded that the spatial frequency response function by SSD has periodical property and is determined by dispersion angle and spectrum shape. More generally, spectrum shape was related with the shape of response function, the dispersion angle affects the lowest spatial frequency, and color cycle number can modify the distribution of low and high spatial frequency to change the smoothing effect. Applied to multidimensional SSD, the response function characters can give the guiding principle for optimization.