NOCE Ophthalmic Products and Frames 5

Question 1

Which frame measurement describes the total horizontal width of the frame front, from the outermost edge of one endpiece to the other?

Accepted Answer

Total frame width (A + DBL + A)

Answer

The total frame width equals the sum of both eye sizes plus the DBL (A + DBL + A), spanning the full width of the frame front.

Question 2

A patient chooses polarized lenses. In which situation would polarized lenses be LEAST beneficial?

Accepted Answer

Looking at a car's LCD instrument cluster

Answer

Polarized lenses can make LCD screens appear dark or produce a black-out effect at certain angles, making instrument clusters or phone screens difficult to read.

Question 3

What is the primary optical purpose of a progressive addition lens (PAL)?

Accepted Answer

To provide a seamless gradient of power from distance at the top to near at the bottom

Answer

A PAL provides a continuous, invisible progression of plus power from the distance zone at the top to the reading zone at the bottom, eliminating the visible segment line.

Question 4

A patient's frame is made of memory metal (beta-titanium or Flexon). What is the key advantage of this material for active patients?

Accepted Answer

It returns to its original shape after bending, reducing breakage

Answer

Memory metal alloys (beta-titanium) are superelastic and return to their original shape after bending, making them very durable for active patients.

Question 5

When measuring a patient for frame fitting, the 'vertex distance' is measured from which two reference points?

Accepted Answer

The front of the cornea to the back surface of the lens

Answer

Vertex distance is the distance from the front surface of the cornea (apex) to the back vertex (posterior surface) of the ophthalmic lens.

NOCE - National Opticianry Competency Examination Practice Test

NOCE - National Opticianry Competency Examination Practice Test

NOCE Ophthalmic Products and Frames 5