A closer look at the eye of a butterfly

Ultrastructure and adaption in the Rectina of Aglais Urticae, Ledidoptera. By, Springer. Also a big thank you, to Iris Scientist for pointing this out to me.

Some butterfly's eyes are covered in tiny hairs, known as Interfacial hairs. These hairs are believed to help orientate light which penetrates the butterfly's eye and, so are expected to perform like that of Corneal Nipples. [Springer] For more information, please go to... Link.Springer.com

This Peacock Butterfly's eye showing the Interfacial hairs covering the
surface area of the eye, also showing some minuscule particles of debris
caught up with-in the interfacial hairs.

I always thought that these hairs were to protect the delicate eye of the Butterfly from tiny particles found floating in the atmosphere, as minuscule particles of dust/debris have shown-up in amongst these hairs in the few photographs i have taken of Butterfly eyes. So this seems to be another effective use for these Interfacial hairs.

The eye of the Red Admiral butterfly, again the hairs
covering the surface area of the eye acting as a trap
for tiny particles of debris.