Have TV Questions? Ask a TV Technician
Each spot (pixel) that you view in the picture is made by a single mirror moving back and forth on the DMD. In total, there are over a million of these tiny mirrors, and the white spots you see are those mirrors that have stuck in the "On" position. These mirrors get jammed and hence this problem.
You can contact Samsung Support for the same. You have to call 1.800.726.7864 and request a service. Since it is only 4 years old, they might consider it as a premature failure of light engine and give you a discount, but you will have to persuade for that. Usually it costs around $800 to fix the problem. Hope it helps. If you have any other queries then I would be glad to assist you further.
I'm sorry to give you such a bad news but it would have been unprofessional of me and unfair to you if I wouldn't have given an honest answer.
Please click the green ACCEPT button ONLY if you are SATISFIED with my help, so that I'll be credited for assisting you. Before leaving a negative feedback, give me one more chance to help you further. Positive Feedback and Bonuses are greatly appreciated!!