论文部分内容阅读
为提高光学表面的功率谱密度检测精度,研究了白光干涉仪仪器传递函数(ITF)的产生机理和标定方法。将白光干涉仪作为非相干成像系统,对正弦表面干涉光强进行Bessel函数展开,通过干涉光强的频谱强度变化研究白光干涉仪对正弦表面高度的作用机理,利用数值仿真计算了白光干涉仪对正弦表面的衰减程度。采用30、80、120 nm高度的台阶标准板对商品白光干涉仪的传递函数进行标定,并提出了一种可靠的ITF计算方法。理论分析、数值仿真和实验结果表明:ITF随表面高度的增加而增大,此时白光干涉仪对表面高度的响应表现出明显的非线性;表面高度小于λ/10得到的ITF曲线与白光干涉仪光学系统调制传递函数非常接近,白光干涉仪对表面高度的响应接近线性。文中对于白光干涉仪频域传递特性研究和光学表面功率谱密度检测具有重要意义。
In order to improve the detection accuracy of power spectral density on optical surface, the generation mechanism and calibration method of white light interferometer instrument transfer function (ITF) are studied. As a non-coherent imaging system, the white interferometer is used to carry out the Bessel function of the interference intensity of the sine surface. The mechanism of the white-light interferometer’s influence on the height of the sine surface is studied by the change of the spectral intensity of the interference light intensity. The degree of sinusoidal surface attenuation. The transfer function of the commercial white light interferometer is calibrated using a step standard plate with a height of 30, 80 and 120 nm, and a reliable ITF calculation method is proposed. The theoretical analysis, numerical simulation and experimental results show that the ITF increases with the increase of the surface height, and the white light interferometer shows a significant nonlinear response to the surface height. The ITF curve with the surface height less than λ / 10 and the white light interference The optical system modulation transfer function is very close, white light interferometer response to the surface height close to linear. In this paper, the research on the frequency-domain transfer characteristics of white-light interferometer and the detection of optical surface power spectral density are of great significance.