?Foggy Windshield?

[Bill Lee/Virginia]

My windshield is completely clean and clear of any dirt, dust or any RainX. The inner sandwiched material is completely clear. When the sun shines directly on the windshield in the early morning hours and during late evening sun, my windshield appears to fog up and I cannot see thru it. What is the problem? How can I correct it? Thanks in advance.
Bill Lee/Virginia Peninsula