the most common mechanism for this is drying the cornea, when you use a TV, phone, computer , read your blink rate drops from once every 5-7 second to once every 15 seconds and the cornea dries out. There is a world wide epidemic of these due to how much time people spend on screens and reading. Try using preservative free artificial tears hourly waking hours for a week and see if that helps. Then every 15 minutes look away from the computer screen, the TV or the book, focus far away (greater than 20 ft or 6 meters) and blink your eyes forcefully 6-7 times. If this doesn't help you might return to your ophthalmologist, be sure an Macular OCT is done, and have the ophthalmologist look at your cornea before any drops put int.