The installation for scattering light level measurements in the shadow of the coronagraph's external occulting system

The design sophistication of optical instruments with low level instrumental (including diffraction) scattered illumination is very interesting not only for solar asrophysics. The construction of a laboratory installation for measuring intensity of a diffractio-swcattered illumination in a shadow of darkening system of a coronagraph with an exterior eclipse surveyed is described. The method of measuring, permitting to minimize influecing of a light, scattered from interior surfaces of installation is offered. Measuring of intensity of a diffraction-scattered illumination in a shadow of the single disk with different lateral views of edge is conducted. From the obtained experimental data follows that the change of the shape of scattering edge of exterior darkening system can essentially reduce intensity of a diffraction-scattered illumination in the field of an entrance pupil of an external occulted coronagraph.© (2005) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.