Same…but different
An ophthalmologist is an eye doctor specializing in the medical and surgical treatment of eye diseases…and can certainly issue a Rx for a pair of glasses as well.
An optician is supposed to fill spectacle Rxs issued by an ophthalmologist or an optometrist…but in the absence of Government legislation to regulate the practice of refraction, has traditionally been engaged in sight testing process as well despite the fact that he is not institutionally-trained.
An optometrist, on the other hand, is an expert in eye refraction examination and the issuance of a Rx for a pair of glasses (and its dispensing as well)…having undergone prescribed course in optometry at an accredited institution. more