Hello to all,
I'm in brainstorming for a project with very noble applications. I wanted to talk to you so I could find the most direct way to my goal.
How do I, in your opinion, recognize the movement of the eyelids using arduino?
Thank you all,
Ing. Icus89
Look into openCV. Good luck 
Are you allowed to attach anything to said eyelid?
You need to give a lot more detail about your 'noble application' if you actually want help.
Otherwise you'll be getting a lot of different suggestions and you'll just spend your time being a pain in the ass by saying 'no that won't work' when it's because you failed to give detail.
Hi,
Do you need know if they are up or down?
Check to see if you get a change in IR radiation from the eye and eyelid.
What is the application?
Tom.. 
Sorry for my English.
NeilSawhney:
Look into openCV. Good luck
I don't have any skills with OpenCV
INTP:
Are you allowed to attach anything to said eyelid?
You need to give a lot more detail about your 'noble application' if you actually want help.
Otherwise you'll be getting a lot of different suggestions and you'll just spend your time being a pain in the ass by saying 'no that won't work' when it's because you failed to give detail.
Yes, allowed. You are right, my project is about a ocular reader for disable people. It is important that is cheap and open source, accuracy is not important at moment.
TomGeorge:
Hi,
Do you need know if they are up or down?
Check to see if you get a change in IR radiation from the eye and eyelid.What is the application?
Tom..
I need only to take the movement. Check the change of IR radiations are my principal goal for the moment
Most blink sensors I know of use an IR emitter and camera on a glasses frame or baseball hat.
The camera is necessary because it is looking for the bright spot reflected off the eyeball, not total reflection.
I expect there are more options. Probably an iPhone app for it. An iPhone can measure your pulse rate with its camera looking at your face.