Study On Tesing Method For Optical Performance Of The Solar X-ray Grazing Incidence Telescope

In recent years,solar activity and space weather are increasingly focused on with the development of space technology.The solar X-ray grazing incidence telescope is able to observe the solar corona.The soft X-ray grazing incidence telescope can observe the solar corona at the soft X-ray waveband,which has irreplaceable advantages in observing solar activities and is an important instrument to monitor solar activities and to forecast space weather.This paper studied the ground testing method for the solar soft X-ray grazing incidence telescope,which provided a testing method for the development of the telescope.The main contents and conclusions were listed as follows.1.Research on the method for characterizing surface roughness of Wolter type I grazing incidence mirror.The surface roughness characterizing method for surface roughness such as mechanical probe scanning method,white light interference method,atomic force microscope,and optical scattering method were compared.And then the X-ray scattering method was chosen to characterize the surface roughness of Wolter type I grazing incidence mirror according to the structure of it.The influence on the angular distribution of the total scattering intensity due to the surface figure was analyzed according to the Harvey-Shack surface scattering theory and imaging theory when the incident beam is narrow on the condition of smooth surface approximation.And then,it was determined that the medium and high frequency components of the surface roughness can be accurately measured by X-ray scattering method when the incident beam is narrow on the condition of smooth surface approximation.The scheme for characterizing the surface roughness by X-ray scattering method was designed considering the influence of the refractive index of Wolter type I grazing incidence mirror.The feasibility and accuracy of the scheme were verified by simulation,which lay a solid theoretical foundation for characterizing the surface roughness of Wolter type I grazing incidence mirror by X-ray scattering method.2.The soft X-ray grazing incidence reflectometer was designed and constructed to characterize the effective area of the solar X-ray grazing incidence telescope.The energy dispersion system was scaled,and the accuracy of the energy scale was verified since the transmission of the pre-filter measured by experimental device was consistent with that measured by the synchrotron radiation source of the institute of high energy physics of the Chinese academy of sciences,which proved the accuracy of the energy scale of the dispersion system.The reflectivity of super-smooth planar mirror was measured and the measured results agree with the theoretical values which verified the accuracy of the reflectometer.The effective area of soft X-ray grazing incident telescope at channel X₃ was characterized to be 15.13mm² by soft X-ray grazing incident reflectometer at wavelength of 1.33nm.And the relative error to the theoretical value of 15.98mm².3.A fast method was proposed for characterizing angular resolution of soft X-ray grazing incidence telescope according to the image quality analysis model.First,a resolution test target for a soft X-ray grazing incidence telescope was imaged at the visible light waveband.Second,the aperture diffraction effect was removed from the resolution test target image by the image restoration method,which leads to a resolution test target image that does not include the aperture diffraction effect.Third,the scattering point spread function of the telescope due to the surface roughness of the grazing incidence mirror was calculated by the surface scattering theory.Finally,the resolution test target image of the telescope in the working band is obtained by convolution of the resolution test plate image without the aperture diffraction effect,the diffraction point spread function of the working band and the scattering point spread function,according to which the angular resolution is calculated to be 9.72".