Dispensing Instrumentation Questions and Answers Flashcards
6 cards from real ABO NOCE Basic Opticianry practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 6 Dispensing Instrumentation Questions and Answers flashcards as text
When using a frame tracer (frame pattern maker), what information is captured for use by an edger?
Answer: The exact shape (silhouette) of the lens opening, including its size, position, and geometric center
A frame tracer digitally captures the lens shape from the frame (or demo lens), producing a data file used by the edger to cut the lens to the exact required shape.
An optical bench is used to measure:
Answer: The focal length and optical properties of lens systems, including back vertex distance and focal power
An optical bench is a laboratory instrument for measuring lens system properties including focal lengths, vergence, and back vertex power with precision.
The purpose of a segment height gauge (seg height ruler) is to:
Answer: Measure the vertical distance from the lowest point of the lens to the top of the bifocal segment
A seg height gauge measures the height of the bifocal or progressive addition segment from the bottom of the lens, used to verify correct placement per the dispensing prescription.
What is the function of a spectacle frame warmer (frame heater)?
Answer: To heat plastic frames to make them pliable for adjustment and lens insertion
Frame warmers (salt pans, hot air, or bead warmers) heat plastic frames to 60–80°C, making the material soft enough to safely adjust the frame and insert or remove lenses without cracking.
The purpose of a thickness caliper in opticianry is to:
Answer: Measure lens center thickness and edge thickness to verify they meet ANSI Z80.1 minimum thickness requirements
Thickness calipers measure the center and edge thickness of finished lenses to ensure they meet minimum thickness requirements per ANSI Z80.1 and are safe for dispensing.
During lensometer verification, 'base-in' prism is confirmed when the mire target is displaced:
Answer: Toward the nose (toward the optical center from the nasal side)
Base-in prism displaces the mire nasally (toward the nose) when the lens is held in standard position. The prism base is opposite to the mire displacement direction.