Focusing the Image. Infants and children with high refractive errors require glasses. or contact lenses to achieve good vision and avoid amblyopia. The ophthalmologist can objectively quantify an abnormal refractive error by altering the quality of the red reflex obtained with a retinoscope. Although parents are often anxious that their infant will not tolerate glasses, any infant who has a visual problem that can be corrected optically does extremely well.