A retinoscope is a handheld device used by eyecare professionals to determine whether your eyes are “20/20,” or have difficulties in seeing things up close or far away.
By shining a light back and forth across your eye, eye doctors are able to determine (usually with great accuracy) if your vision needs corrective lenses by “dialing” the retinoscope so that the light focuses properly at the back of the eye on the retina.
This simple procedure is called a retinoscopy.
