小波在基于功率谱密度特征曲线评价中的应用

为了解决功率谱密度仅仅是一种强激光条件下光学元件表面质量评价指标,无法对通过加工来消除某频段误差进行确定性指导这一问题,采用小波理论对光学元件表面误差进行了分析和试验验证,在利用功率谱密度特征曲线找到表面误差不合格频率带的基础上,利用二维连续小波变换得到了能作为加工过程反馈的不合格频率带的对应区域.结果表明,利用此方法能有效地找到特定误差频段对应的区域,从而指导加工,提高加工的效率.

The use of wavelet in evaluating optics based on power spectral density character curve

In order to solve the problem that power spectral density function(PSD) is only an evaluation guideline to specify large aperture optical components' quality of laser system and can't provide effective guidance for eliminating certain frequency segment error,a wavelet method was used to analysis the optical surface errors.Firstly,PSD character curve was used to find the unqualified frequency range;secondly,two-dimensional continuous wavelet transform was used to find the corresponding region of this frequency segment,which can use as feedback to a machining process.The experiments' results show the use of wavelet can find the corresponding region of certain frequency segment effectively.