Cal. Bus. & Prof. Code § 2542

A registered dispensing optician shall dispense contact lenses, including plano contact lenses, only on the valid prescription of a physician and surgeon or optometrist, and acting on the advice, direction, and responsibility of the physician and surgeon or optometrist. The registrant shall also comply with the requirements of Section 2560. A registered dispensing optician shall not dispense a contact lens or lenses, or a plano contact lens or lenses, unless the prescription specifically refers to and authorizes contact lenses. A registered dispensing optician shall not fit a generic type of contact lens or mode of wear for a contact lens contrary to the type or mode, if any, referred to in the prescription.