MAGNIFICATION

Question 1

Method of increasing the retinal image so that enough of the retina is stimulated to send an impulse through the optic nerve to the brain, allowing an object to be perceived.

Answer 1

Magnification

Question 2

Ways of enlarging retinal image

Answer 2

*Moving the object closer
*Enlarging the object itself
*Optical magnification
*Electronic magnification

Question 3

4 Types of Magnification

Answer 3

*Relative distance magnification (RDM)
*Relative size magnification (RSM)
*Optical/Angular magnification
*Electronic/Projection Magnification

Question 4

Moving the object closer or a person approaches the object

Answer 4

Relative Distance Magnification (RDM)

Question 5

It is necessary to focus the image

Answer 5

with lenses or accommodation.

Question 6

The object becomes magnified by two times if we move it half-way closer to the observer’s eye from the original distance.

Answer 6

Relative Distance Magnification (RDM)

Question 7

Formula of Relative Distance Magnification (RDM)

Answer 7

reference distance/new distance (r/d)

Question 8

Increasing the size of an object.

Answer 8

Relative Size Magnification (RSM)

Question 9

Formula of Relative Size Magnification (RSM)

Answer 9

New size/reference size

Question 10

Makes an object at a distance appear closer to the eye, through the use of various lenses or lens systems.

Answer 10

Angular Magnification

Question 11

Increases the size of the image to be through the projection process.

Answer 11

Electronic/Projection Magnification

Question 12

Determination of the Needed Magnification

Answer 12

*What is the achieved visual acuity of the client?
*What is the goal or desired visual acuity of the client?

Question 13

Formula of magnification

Answer 13

Achieved VA/desired VA

Question 14

Formula of magnification

Answer 14

a/r

Question 15

80 wpm

Answer 15

To spot

Question 16

enables identification of a single word

Answer 16

To spot

Question 17

160 wpm

Answer 17

To be fluent

Question 18

enables reading accurately

Answer 18

To be fluent

Question 19

320 wpm

Answer 19

Maximum

Question 20

enables reading accurately at a high speed

Answer 20

Maximum

Question 21

Consider threshold rather than the goal acuity or print size

Answer 21

Reserve or Threshold Acuity

Question 22

one line smaller

Answer 22

Spot

Question 23

three lines smaller

Answer 23

Fluent

Question 24

fives line smaller

Answer 24

Maximum

Question 25

Kestenbaum’s Formula

Answer 25

Take the reciprocal of the best Snellen acuity distance to derive the initial power required to read 1M or standard news print