Hehe. interesting question
On one hand its completely unrealistic. Light dispersion only occurs because of the atmosphere. Space = no atm. = no flares, flashes no nothing. The Sun would be just a really bright spot, like any other star we see on a night sky.
On the other hand its totally realistic. The light source of such intensity would blind the viewer, burning through his eyes, indeed resulting in a loss of vision effect. Permanent though.
Then again the solution to such a problem would be a top priority to find, so it is to assume that future pilots dont suffer from that.
