Fig. 7
From: Performance of Akatsuki/IR2 in Venus orbit: the first year
Point-spread function (PSF) of IR2. a Pre-launch H-band image, taken in the evening through the window of the laboratory, exhibiting halation rings around the bright city lights (three in row). b Mathematical approximation of the IR2 PSF as described in the text. This is intended to be similar to the pattern seen in the real image