answers
A condition of the eye in which light focuses in front of the retina. Caused by either
the eye being too strong or the globe of the eye being too long - ANSWER Myopia
Difficulty accommodating* due to the crystalline lens becoming less elastic. -
ANSWER Presbyopia
Around what wavelenght of light is thought to cause cataracts - ANSWER 460 nm
Axis pliers are meant to do what - ANSWER Turn and rotate a lens
Cr39 Index and abbe - ANSWER Index 1.49 Abbe 59
Crown glass index and abbe - ANSWER Index 1.523 Abbe 60
Trivex Index and abbe - ANSWER Index 1.54 Abbe 43-45
Polcarbanate index and abbe - ANSWER Index 1.58 Abbe 30
Hight index 1.60- 1.67 index and abbe - ANSWER 1.6 abbe 36, 1.67 abbe 32
Ultra high index 1.70- 1.7.4 index and abbe - ANSWER 1.7 abbe 36, 1.74 abbe 33
If somone chose a pair of lenses to put in a frame for primary sports use what
orginazation would have checked the safety of the lenses - ANSWER ASTM
What indication on a frame or glass indicates a pair of saftey glasses - ANSWER
ANSI Z87.1
how thick does a lens from a pair of safety glasses have to be - ANSWER 3 mm
thick or on a perscription higher than +3 at its thinest part needs to be 2 mm
Where is the concentric circles in a lensometer ? - ANSWER Within the recticle
What is a distometer used for? - ANSWER Measuring vertex distance between the
front of the eye and the back of the lens
What is a phoropter used for ? - ANSWER measures the eye's refractive error to
help determine and eye prescription
What is a poalriscope used for? - ANSWER it measures internal stress within lens
, A condition of the eye in which light rays are focused behind the retina Caused by
the eye being too weak or the globe of the eye being too short - ANSWER
Hyperopia
A condition where the eyes have unequal refractive power, greater than 1 diopter. -
ANSWER Anisometropia
A condtion where the two eyes have opposite signs. One eye is Hyperopic and the
other eye is Myopic. - ANSWER Antimetropia
ANSI standards for horizonal prism - ANSWER 0.66△
ANSI standarda for vertical prism - ANSWER 0.33△
an inability to see clearly through one eye. It occurs during childhood, typically when
the nerve pathway between the brain and eye doesn't develop normally. -
ANSWER Amblyopia
Cloudy or opaque crystalline lens due to aging. - ANSWER Cataract
Having a fake crystaline lens or implant from surgery. A patient is given an
intraocular lens implant after cataract surgery - ANSWER Pseudophakia
Missing the crystalline lens - ANSWER Aphakia
Double vision is called - ANSWER Diplopia
Exphoria is what? - ANSWER Tendency to turn outward
Esotropia is what? - ANSWER Permanent turn inward
MBS size equation - ANSWER MBS= ED+Decentration+2
5/8 stell ball, drop ball test is perfomed by who? - ANSWER FDA
At what height is the drop ball test performed? - ANSWER 50 Inches
The drop ball test is meant to test for? - ANSWER Impact resistance
Most wrap around frames are made from what material? - ANSWER Nylon
What frame material is made of a mix of metals - ANSWER Monel
What is the depth of a 7x28 trifocal lens - ANSWER 7mm
What is the first step to netrulize a frame in lensometer? - ANSWER Focus the
eyepiece, turn the eyepiece counter clockwise till blurry and clockwise till clear
What is a lens caliper used for? - ANSWER to measure the thickness of a lens