ABO NOCE Basic Opticianry ABO NOCE MCQ 4 — Questions and Answers
Question 1: When adjusting metal frames, at what angle should the endpiece be set relative to the front to ensure proper temple alignment?
- The temple should extend straight back parallel to the ground (Correct answer)
- The temple should angle downward 10-15 degrees
- The temple should angle upward 5 degrees
- The temple should be bent inward toward the ear
Correct answer: The temple should extend straight back parallel to the ground
Properly adjusted temples should extend straight back from the hinge, parallel to the floor, before the earpiece bends over the ear.
Question 2: What is the formula for calculating the minimum blank size (MBS) for a single vision lens?
- MBS = ED + 2(decentration) + 2mm (Correct answer)
- MBS = A + DBL + 2mm
- MBS = B + decentration + 4mm
- MBS = PD + frame PD + 2mm
Correct answer: MBS = ED + 2(decentration) + 2mm
Minimum blank size = effective diameter (longest chord) + twice the decentration amount + a 2mm safety margin.
Question 3: A patient has a monocular PD of 32/30 mm. What does this notation indicate?
- 32 mm right eye distance PD and 30 mm left eye distance PD (Correct answer)
- 32 mm total PD and 30 mm near PD
- 32 mm right eye near PD and 30 mm left eye near PD
- 32 mm binocular distance PD and 30 mm segment height
Correct answer: 32 mm right eye distance PD and 30 mm left eye distance PD
In monocular PD notation, the first number represents the right eye measurement from the midline and the second represents the left eye measurement.
Question 4: What ANSI standard governs prescription ophthalmic lenses in the United States?
- ANSI Z80.1 (Correct answer)
- ANSI Z87.1
- ANSI Z80.3
- ANSI Z80.5
Correct answer: ANSI Z80.1
ANSI Z80.1 sets the tolerances and requirements for prescription ophthalmic lenses dispensed in the United States.
Question 5: A high-minus lens patient complains of 'jack-in-the-box' phenomenon. What is happening?
- Objects suddenly appear when entering the peripheral field due to the ring scotoma (Correct answer)
- Objects appear magnified in the center of the visual field
- The lens causes objects to jump when moving the eyes
- Prism causes vertical diplopia at the edges
Correct answer: Objects suddenly appear when entering the peripheral field due to the ring scotoma
High-minus lenses create a ring scotoma at the prismatic lens edge, causing objects to 'pop' into view suddenly as they cross this boundary.
Question 6: When dispensing progressive addition lenses, where should the fitting cross be positioned?
- At the pupil center with the eye in primary gaze (Correct answer)
- 4mm below the pupil center
- At the lower lid margin
- At the geometric center of the frame
Correct answer: At the pupil center with the eye in primary gaze
The fitting cross on a progressive lens is placed at the pupil center in primary gaze to ensure the distance zone is correctly aligned.
Question 7: What is the Abbé value, and how does it affect lens performance?
- A measure of chromatic dispersion; higher values mean less chromatic aberration (Correct answer)
- A measure of impact resistance; higher values mean more resistant
- A measure of refractive index; higher values mean thinner lenses
- A measure of UV absorption; higher values mean more UV blocked
Correct answer: A measure of chromatic dispersion; higher values mean less chromatic aberration
The Abbé value (or V-number) measures chromatic aberration; higher Abbé values (like crown glass at ~59) produce less color fringing than lower values (like polycarbonate at ~30).
ABO NOCE Basic Opticianry ABO NOCE MCQ 4
When adjusting metal frames, at what angle should the endpiece be set relative to the front to ensure proper temple alignment?