The pupillary<unk>  acts to increase the size of the pupil to allow more light to enter the eye. It works in opposition to the pupillary constrictor. Pupil dilation occurs when there is insufficient light for the normal function of the eye, and during heightened sympathetic activity, for example in the "fight-or-flight reflex". this muscle also do it's action in fight and flight situation (sympathetic nervous system)
Iris dilator muscle
Iris sphincter muscle
Oculomotor nerve
Iris pigment epithelium
Corneal endothelium
Scleral lens
Choroid glomus
Corneal limbus