To observe the solar corona, stray light in the coronagraph, arising primarily from an external occulter and diaphragm illuminated directly by the Sun, should be strongly suppressed. A toothed occulter and diaphragm can be used to suppress stray light because they diffract much less light in the central area than a circular disk. This study develops a method of computing the light diffracted by a toothed occulter and diaphragm, obtaining the optimum shape using this method. To prove the method’s feasibility, the diffracted fields of circular and rectangular disks are computed and compared with those calculated by a conventional method.
© 2013 Optical Society of America
Diffraction and Gratings
Original Manuscript: April 10, 2013
Revised Manuscript: September 1, 2013
Manuscript Accepted: September 2, 2013
Published: September 30, 2013
Mingzhe Sun, Hongxin Zhang, Heyang Bu, Xiaoxun Wang, Junlin Ma, and Zhenwu Lu, "Computation of the diffracted field of a toothed occulter by the semi-infinite rectangle method," J. Opt. Soc. Am. A 30, 2140-2149 (2013)