NOCE Optical Instrumentation Usage 3

Question 1

When calibrating a lensometer, a technician uses a standard lens of known power. If the reading differs from the known value, the next step is to:

Accepted Answer

Adjust the eyepiece diopter compensation first, then recalibrate

Answer

Before calibrating the instrument, the eyepiece must be properly focused for the examiner's eye to eliminate measurement error from accommodation.

Question 2

An optical coherence tomographer (OCT) used in an optical setting primarily helps the optician by:

Accepted Answer

Detecting macular pathology that may affect vision correction outcomes

Answer

OCT imaging can detect retinal pathology such as macular degeneration that may explain reduced visual acuity not correctable with spectacles.

Question 3

A lensometer with an automated printout system marks a dot on the lens. This dot represents the:

Accepted Answer

Optical center of the lens

Answer

The lensometer marks the optical center (or reference point) of the lens so the optician can verify correct placement relative to the patient's pupil.

Question 4

Which of the following correctly describes the function of the axis wheel on a manual lensometer?

Accepted Answer

It rotates the target to align the cylinder axis of the lens

Answer

The axis wheel rotates the lensometer target to align with the cylinder axis of the lens being measured, allowing the cylinder meridians to be properly read.

Question 5

When measuring a progressive addition lens on a lensometer, the reference point for the distance power should be:

Accepted Answer

The prism reference point (fitting cross)

Answer

For progressive lenses, distance power is measured at the prism reference point (fitting cross), which is marked by the manufacturer.

NOCE - National Opticianry Competency Examination Practice Test

NOCE - National Opticianry Competency Examination Practice Test

NOCE Optical Instrumentation Usage 3