I noticed especially in oncoming sunlight a residue on the inside of my windshield. After cleaning thouroghly, it still keeps reappearing. I have a 99 Camry. Is there some sort of filter that this car is equipped with that filters the inside air? Could this be the reason for the residue?

If you drive with the ventilation on "Recirculate" instead of bringing in outside air, you will have this problem. Is this the solution?