Mitsubishi Big screen

This problem could be as simple as dirt or dust inside on the lens of the picture tubes or on the mirrors inside the projection tv. It could also be the blue tube is on its way out or the focus on the blue tube needs alighnment . This set has extremly high voltage inside, so its not for the do-it your selfer to mess with!! Now theres nothing wrong with a do-it your selfer but in this case save a life, and call a tech in to see if it just needs cleaning or light alighnment. If you call one, watch how they take apart the screen assy. from the tv and see how they clean the set ,so you can do it next time. Now like I said it could be a picture tube going bad too so please dont be too disapointed when they tell ya that. But depending on how old the set is ?? It might be worth investing in the set?? Also another thing , when the tech comes in they MAY say the set needs to go to the shop to be looked at . This is a way to get more cash out of ya as Ive seen simple cleaning or adjustment repairs turn into 500 to 700 bucks when in reality, it could have been done in the home for a hundred or so. Dont be afraid to pay someone a hundred or two, if they fix a broken set in the home, as believe me you saved a bundle when you let them, cause when it goes out the door (the set) tack on an extra 200 at least. Good luck