Hi all!
Nathan-NIS I've finally resolved the problem.
If you want to detect the eye blink with your headset Mindwave you should do an unexpected manipulation of your headset ]
I'm joking! the tip is to detect when the EEG datas theta or the raw datas values reach a threshold because eye blinks are artifacts i.e some noise for these values.
When you blink your eyes, you should detect a peack between two raw datas 8)