Vision and Physiological Optics

Question 1

diverging lens, focuses light at point in front of the lens

Answer 1

concave

Question 2

converging lens, focuses light at a point behind the lens

Answer 2

convex

Question 3

lens power is the inverse of ___________

Answer 3

focal length

Question 4

light refracted at _______ and majority at the __________

Answer 4

natural crystalline lens, cornea

Question 5

parallel rays focused posterior to retina, need a stronger more (+) convex lens that converge earlier

Answer 5

hyperopic (farsighted)

Question 6

parallel rays focused anterior to retina, correct with a bi-concave lens that diverges rays then allows eye to converge

Answer 6

myopic (nearsighted)

Question 7

2 focal points

Answer 7

astigmatism

Question 8

increased curvature of lens due to ciliary muscle contraction

Answer 8

accommodation

Question 9

decreased accommodation causes _________

Answer 9

presbyopia

Question 10

angle of resolution on retina, determined by distinguishable objects in distance

Answer 10

minimum angular resolution (MAR)

Question 11

legal blindness defined as _______ or worse, or visual field of ______ degrees or less

Answer 11

20/200, 20 degrees

Question 12

Snellen denominator equal to ______ times 20

Answer 12

min arc

Question 13

a hyperopic eye is commonly known as _________, where parallel rays are focused _______ to retina

Answer 13

farsighted, posterior

Question 14

a myopic eye is also known _________, where parallel rays are focused _______ to retina

Answer 14

nearsighted, anterior