Lab 10: Vision単語カード | Quizlet

Rotational nystagmus

fast: direction of spin

slow: opposite of spin

Post-rotational nystagmus

fast: opposite direction of spin

slow: direction of spin

rods

detect light and responsible for black-and-white vision. Rods

are useful in dim light, but they provide less visual acuity

cones

detect specific wavelengths of light and are responsible for

color

vision. Cones require bright light but provide high visual acuity

snellen chart

used to test visual acuity or the ability to focus

incoming light on the retina. A person with normal vision,

emmetropia

, has a visual acuity of 1 (20/20 vision).

emmetropia

normal vision 20/20

hyperopia or hypermetropia

focal point of the incoming light is behind the retina because

the eyeball is too short

farsighted

greater than 1 (20/10)

+

myopia

focal point of the incoming light is in from of the retina because

the eyeball is too long

nearsighted

less than 1 (20/200)

Jaeger chart

near visual acuity

testing for hyperopia

The larger the print must be in order to read it, the less near visual acuity the person has.

corna

responsible for the refracting or bending of light rays so they fall on one spot of the retina

lens

responsible for fine-tuning the focusing of the light on the retina

astigmatism

defective curvature of the cornea or lens of the eye

greens chart

test used for astigmatism

right eye

OD oculus dexter

left eye

OS (oculus sinister)

divergent corrective lenses

are used to correct vision in someone with myopia

near sighted

convergent corrective lenses

used to correct vision in someone with hyperopia

far sighted

amsler grid

used to detect changes in the retina as well as in the optic nerve and the pathway of visual information in the brain

ophtalmoscope activity

tool used to view the inside of the eye

close, contract converge, constrict

lens thicken

what are the 4 c's to focus on something close