The incident occurred Monday at approximately 8:45 a.m.
Police say the male suspect approached the victim's car on the eastbound Route 30 bypass off-ramp to Route 100 after a traffic incident.
Once at the driver's door window, police say the suspect punched the 44-year-old woman in the forehead and stole her prescription glasses.
The suspect then returned to his vehicle, fled southbound on Route 100, and took the Pottstown Pike exit ramp towards West Chester.
The male was operating a mid-1980's Dodge Ram 50 pickup. The pickup was blue in color and weathered. The word "Dodge" on the tailgate was a different color, possibly tan.
The suspect is described as a white male between 25 and 30 years of age. He was approximately 5'10 tall and weighed approximately 200 pound. He had light brown or dirty blond hair that was down to his shoulders. He was wearing a blue hooded sweatshirt, brown Carhartt pants, and tan boots.
Police have released a sketch of the suspect.
Anyone with information on the suspect is asked to contact the West Whiteland Township Police Department at 610-363-0200 or 610-692-5100.