Since a long time, my screen sparkles sometimes to the vertical position. So I had charge my battery to 100% but it's same problem. And now during I'm write this post, the screen is good ! It's sparkles randomly... I'm in Custom Kikat Rom (From Demelza post) but it was the same problem with my old ROM in Jelly Bean.
Thank you for your response, I have downgrade my ROM to Lindenberg (Jelly Bean) because when i was on this ROM, he had sparkles just one time... I've installed just the necessary for 1 weeks, I will see if all is good.