Blurred vision at stoplights can be caused by poor distance vision or abnormal color vision. There are many reasons for poor vision. Most patients may have a refractive error that requires an optometric correction to see if glasses are needed. This is especially true for patients with high myopia who have difficulty seeing traffic lights when walking or driving in dim or foggy weather. It may also be caused by abnormal color vision, which includes color weakness and color blindness. Most patients are born with genetic predisposition and cannot improve their symptoms through treatment. The first thing to do is to check your eyesight to determine the cause of the vision loss, and you can also undergo a color blindness test to rule out the possibility of color vision abnormalities. Patients with abnormal color recognition are not allowed to work as drivers.