BRS Low Vision Aids & Devices 4

Question 1

A patient is prescribed a 6× Keplerian telescope. Which characteristic distinguishes this device from a Galilean telescope of equal power?

Accepted Answer

Keplerian telescopes provide a wider field of view and higher image quality but require an erecting prism

Answer

Keplerian (astronomical) telescopes produce an inverted image and require an erecting prism system, but they offer superior field of view and image quality compared to Galilean designs at the same power.

Question 2

Which patient characteristic is the MOST important contraindication for prescribing a bioptic telescope for driving in states where it is permitted?

Accepted Answer

Inability to rapidly shift gaze between the carrier and telescope

Answer

Safe bioptic driving requires the patient to quickly and reflexively alternate between the wide-field carrier lens and the telescope, and inability to do so is a primary contraindication.

Question 3

When evaluating a patient for a video magnifier (CCTV), which feature is MOST beneficial for a patient with extreme photophobia?

Accepted Answer

Reverse polarity (white text on black background)

Answer

Reverse polarity displays white text on a black background, dramatically reducing the amount of light emitted from the screen and alleviating photophobia.

Question 4

A BRS recommends a portable electronic magnifier (PEM) for a patient. What is a key LIMITATION of PEMs compared to desktop video magnifiers?

Accepted Answer

PEMs typically have smaller screens, limiting the area visible at one time

Answer

Portable electronic magnifiers have smaller screens than desktop units, which limits the amount of text or image visible at any magnification level.

Question 5

Which principle explains why increasing magnification with an optical device also reduces the field of view?

Accepted Answer

The inverse relationship between magnification and angular field in telescope optics

Answer

In telescope optics, field of view and magnification are inversely related — as magnification increases, the angular field of view proportionally decreases.

(BRS) Blind Rehabilitation Specialist Certification Practice Test

(BRS) Blind Rehabilitation Specialist Certification Practice Test

BRS Low Vision Aids & Devices 4