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Optical Lecture Test 1
Optical Lecture Fall 2021 Test 1
42
Other
Graduate
10/08/2021

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Cards

Term
What ophthalmic lens company invented photocromic lenses?
Definition
Corning
Term
Why was the invention of spectacles not a major event?
Definition
Not many people can read and there was not much use of printed media back then
Term
What name do we give to ophthalmic lenses when they are created on a 6.00 D base curve?
Definition
Meniscus
Term
If a patient is given aspheric lenses, what might they enjoy about them optically?
Definition
Wider field of view

Spherical aberration correction (makes corrected image less blurry)

Improved peripheral vision
Term
Why were minus cylinder lenses created?
Definition
They couldn't fit the base curve on front so they put it on the back
Term
What is the difference between today's AR coatings and the original?
Definition
Back in the day the AR coatings were 1 coating and today at least 5 coats are used
Term
ROYGBIV

The colors of the visible spectrum are?
Definition
Red
Orange
Yellow
Green
Blue
Indigo
Violet
Term
Same BC stands for?
Definition
Same Base Curve
Term
Which wavelength of light immediately follow the visible spectrum?
Definition
Short Infrared
Term
Whose theory of light from the 1600's explains all that we know about the behavior of light today?
Definition
Huygens
Term
The first bent lens had what dioptric value for its curvature where the lenses used to be flat?
Definition
+1.25
Term
What is the speed of light in the Hoya Profection lens?
Definition
1.70 is the n for Hoya so 186,000 miles per second divided by 1.70

109,412
Term
When light rays enter a polycarbonate lens they will bend?
Definition
Towards the normal
Term
What is the lowest specific gravity of any lens ever made?
Definition
Polycarbonate or Trivex
Term
What are the ingredients of Crown glass?
Definition
Silica sand
Potassium oxide
Soda
Lime
Arsenic/others
Term
The difference with Flint glass?
Definition
Flint has lead oxide
Term
Which glass is the most difficult to manufacture?
Definition
Barium. Has better optics but difficult to manufacture just like flint imagine chandeliers chips easily
Term
Pittsburgh plate glass makes what?
Definition
CR-39
Term
Polycarbonate is the go to recommendation by opticians because?
Definition
It is the safest lens in the world
Term
Who is the biggest lens manufacturer today?
Definition
Essilor
Term
The FDA decided you have to temper glass and had what kinds of tests for them?
Definition
Drop ball test.

But you couldn't test plastic that way as it would scratch. So the FDA said lets let the manufacturer test and they did batch testing
Term
Light is divergent meaning?
Definition
Light spreads in all directions
Term
20 feet =
Definition
20/20 vision

Because of diverging light we do eye exams at 20 feet
Term
Why does light bend when it hits a lens
Definition
Its being slowed down and being pushed. Imagine it crashing at 186,000 then it hits the lens and instantly goes to 124,000
Term
When light hits a lens at 186,000 miles per second what is the new speed on contact?
Definition
124,000 and that is a 62k drop. The faster one is pushing on the slower one
Term
Incident upon surface is not right the words we want to see are?
Definition
Angle of incidence
Term
What is the definition of angle of incidence
Definition
The angle which an incident line or ray makes with a perpendicular to the surface at the point of incidence.
Term
1.80 is what?
Definition
Index 8 the highest glass index in the U.S.
Term
Plus lenses have what type of motion?
Definition
Against Motion (Move to the right it goes left)

Some patients call is "Swing"
Term
What is gods gift to opticianry
Definition
Presbyopia

farsightedness caused by loss of elasticity of the lens of the eye, occurring typically in middle and old age.
Term
farsightedness caused by loss of elasticity of the lens of the eye, occurring typically in middle and old age. is called what?
Definition
Presbyopia
Term
If the index is higher than light will do what when it hits the lenses?
Definition
Slow down more
Term
If the globe is "too short" then its?
Definition
Hyperopia

eye too weak
globe too short
Term
What is the age where you don't really see myopics?
Definition
Before the age of 7
Term
Everyone is born basically what?
Definition
Hyperopic
Term
The perfect human eye should be
Definition
59 diopters of power
Term
How do we correct hyperopia?
Definition
Plus lenses
Term
1875 was when?
Definition
The diopter was invented
Term
If light goes from a dense to a denser medium it?
Definition
Will be bent towards the normal
Term
If light goes from a dense to a less dense medium it?
Definition
Will be bent away from the normal

unless THE INCIDENT LIGHT STRIKES THE SURFACE AT A PERFECT 90 DEGREE ANGLE
Term
What is the definition of refraction?
Definition
The bending of light as it passes obliquely from one medium to another of a different index of refraction (N)
Term
Who discovered refraction?
Definition
Claudius Ptolemy
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