Does a chickens eyes turn white when they sleep?

[Labbec]

My chicken has a white film over her eyes that lifts when she turns her head and is startled. She is laying on a nest and has not got up. She has the white film over her eyes while she is laying there. Is this normal for when a chicken sleeps? or is something wrong with her?

 

[XxMingirlxX]

Chickens have a translucent third eyelid that goes across the eye, could this be what you are seeing?