4 Spectacles

Question 1

(TP) TO FUNCTION AS CORRECTING LENS …

A. The lens primary focal point F coincides with the
far point of the eye
B. The lens secondary focal point F’ coincides with the far point of the eye
C. The lens primary focal point F distance is equal to the axial length of the eye
D. The lens secondary focal point F’ distance is equal to the axial length of the eye

Answer 1

B. The lens secondary focal point F’ coincides with the far point of the eye

Question 2

(TP) the unit of vergence is…

Meters
Centimeters
Arcmin
Diopters

Answer 2

M-1

Diopters

Question 3

What is the required optical power of a lens to produce the SAME optical effect at a DIFFERENT location?

Answer 3

The effective (downstream) optical power

Question 4

(TP) hyperopia picture with a +10D lens in front of the eye with a vertex distance 15mm. What’s the power of hyperopia?

Answer 4

+10.00 vertex distance 15mm

Question 5

(TP) myopia picture with a -10D lens in front of the eye with a vertex distance 15mm. What’s the power of myopia?

Answer 5

-10.00 vertex distance 15mm

Question 6

The _________ becomes significant if the spectacle prescription is +- 4.00D or more

Answer 6

Vertex distance

Question 7

If a person has a 12mm vertex and spectacle Rx of +12.00, what’s their cls power?

Answer 7

+14.00

Question 8

If a patient has a vertex distance of 8mm and spectacle Rx of -5.50D, what’s their cls Rx?

Answer 8

-5.25D