Effect of tilted metallic mesh on modulation transfer function of optical system
(0) In order to analyze the effect of a tilted metallic mesh on the modulation transfer function (MTF) of an optical system, the relation between the MTF and tilted angle of the mesh was established through calculating the point spread function (PSF) of the tilted mesh using a model based on Huygens-Fresnel diffraction theory and then conducting Fourier transform on the calculated PSF. It was found through analyses that the density of triangular spikes on the MTF curve is compressed by 1/cos(θ) times along axis x, and the MTF values are degraded due to the stretch and asymmetrical distribution of diffraction spots of the tilted mesh; moreover, when the aperture of the mesh is so small that it is the optical stop itself, the cutoff frequency of MTF along axis x decreases by cos(θ) times and the MTF values drop largely. The degradation effect on MTF caused by a tilted mesh can be reduced by using a large-size metallic mesh and increasing the porosity ratio of metallic mesh.
modulation transfer function tilted metallic mesh optical imaging Fraunhofer diffraction
Zhengang Lu Zhigang Fan Dandan Zheng
Postdoctoral Research Station of Optical Engineering, Harbin Institute of Technology,Harbin, P. R. C Postdoctoral Research Station of Optical Engineering, Harbin Institute of Technology,Harbin, P. R. C Department of Automation Measurement and Control, Harbin Institute of Technology, Harbin, P. R. Chin
国际会议
第五届仪器科学与技术国际学术会议(ISIST 2008)Fifth International Symposium on Instrmentation Science and Technology
沈阳
英文
1-6
2008-09-15（万方平台首次上网日期，不代表论文的发表时间）