Frame measurements, fitting, and adjustment techniques tested on optician certification exams.
30 cards · basic cards · AI-written, checked twice. Edit anything.
- What is pupillary distance (PD)?
- Distance between the centers of the pupils, measured in millimeters, for lens positioning.
- What does pantoscopic angle refer to?
- The angle of the eyeglass frame tilted downward at the temples, typically 8-10 degrees.
- Define face form angle.
- The angle at which the frame sits on the face in profile, typically 8 degrees for standard fitting.
- What is wrap angle in frame fitting?
- The angle at which the frame temples curve around the sides of the head, typically 0-3 degrees.
- What is vertex distance?
- Distance from the back surface of the lens to the front of the cornea, standard is 12 mm.
- How is bridge width measured?
- Distance in millimeters between the inner edges of the two lenses where they meet at the bridge.
- What is the typical PD for an adult?
- 54-74 mm for distance, with 58-68 mm being most common.
- How are temple lengths measured?
- From the hinge to the end of the temple arm, measured in millimeters.
- What is meant by frame alignment in fitting?
- Positioning the frame so lenses are centered on pupils and frame sits symmetrically on the face.
- What is the purpose of adjusting pantoscopic angle?
- To position lenses properly for correct viewing angle and to reduce unwanted prism effects.
- What tool measures pupillary distance?
- A pupillometer or PD ruler is used for direct measurement from the patient.
- Define temple bend in frame adjustment.
- The bend at the temple where it angles downward from the frame front.
- What is the standard bridge width range?
- Typically 14-24 mm, with 18-20 mm being most common.
- How should a frame sit on the nose?
- The bridge should rest evenly across the nose with equal pressure on both sides, leaving no gaps.
- What is the purpose of nosepads?
- To provide a comfortable base for the frame to rest on the nose and distribute weight evenly.