Shared Flashcard Set

Details

abo optical
optical review seminar part 2
67
Other
Not Applicable
10/31/2012

Additional Other Flashcards

 


 

Cards

Term
when you incease the index of a lens do you  change the speed of light traveling through the lens medium
Definition
yes the speed of light will decrease
Term
what part of the retain is concerned with visual acuity and color perception
Definition
fovea
Term
an emmetropic eye is a
Definition
normal eye (eye with no reft error )light focus on the retain
Term
directing the visual axis of the eyes to near point is  
Definition
convergence
Term
it is not recommended to heat treat lenses stronger than
Definition
7.00D
Term
it would be necessary to ? the lens to mount it in a nylon suspension type frame
Definition
groove
Term
warpage may be removed from a plastic lens by placing the frame and the lens in a
Definition
salt pan
Term
the RX of patient is OU -9.25 -0.75X180 what are the recommended precautions to take in prder ti insure proper fitting
Definition
monoculat PD and OCHT measurements
Term
which of the following is not a cause of one lens being higher than the other
Definition

a bent earpiece

a bend in the temple shaft

a skewed bridge

one ear higher than the other

ALL OF THEM ARE POSSIBLE CAUSE

Term
if the wearer complains of the bifocal line being some what in his way  when driving the problem may be alleviated by decreasing the distance between pads
Definition
false
Term
the fitting triangle is
Definition
a triangle representing the main supporting point for a pair of glasses
Term
if the eyelashes rub the lenses  the fitter should
Definition
increase the vertex distance
Term
if the wearer complains that the glasses feel snug but still slip down the nose one likely cause is that
Definition
pressure is being applied by the temple shafts anterior to the ear
Term
when viewing the wearer from the front it is discovered that the frame sits too far to the left (wearer's right )on the wearer's face .this could be cause by ?
Definition

both pads shifted to wearer's left or

the wearer's nose being crooked

Term
if both nose pads press the nose or indent too much what is probably not a possible cause
Definition
temple spread is not even
Term
to eliminate a gap between the lens and a metal eyewire ,the best alternative is to
Definition
place a strip of lens liner at the point exactly opposite the gap
Term
which factor is nonessential in dispensing the progressive add lens
Definition

a good pantoscopic angel

short vertex distance

large b dimension

good monocular lens centration

ALL OF THE ABOVE ARE ESSENTIAL

Term
what is the geometrical center distance of frame marked A 50/DBL 17
Definition

add the a with the dbl 50+17=69

that is the geometrical center distance

Term
the larger the frame difference ? the lens shape
Definition
norrower
Term
if a frame dimensions are A 50 and the ED 55 with frame difference of 8 ,what is the B
Definition

take the A 50 mearsurement - 8 the difference and the is the B

 

ANSRW IS 42

Term
a frame is marked 52/18 the lens shape is round ,what is the effective diameter of the lens ?
Definition
52 mm lens is round
Term
which error is of no consequence in verifying correctness of frame and lenses
Definition

air space between lens and frame

chips in the lens edge between bevel and lens surface

distortion (unevenness)in lens edge between bevel lens surface

ALL OF THE ABOVE ARE OF CONSEQUENCE

Term
when the wearer's PD is less than the frame FD
Definition
positive face form is required
Term
the new bifocal wearer must
Definition
drop the eye to read a book
Term
when the frame front is tested for four point touch but only touches in the two temporal eyesores the frame
Definition
has face form
Term
which of following errors will not be detected by a four point touch test
Definition
skewing
Term
it is unnecessary to use heat in adjusting a zly frame when
Definition
changing the pantoscopic angel
Term
if the pad arms bent up and the pads re-aligned this adjustment will
Definition
drop the front
Term
what is the final step in fiiting a frame to a patient
Definition
adjusting the temples
Term
if the frame is crooked with the right side higher then the left which is not a possible cause
Definition
the pantoscopic tilt of the right side needs to be increased
Term
the main for the use of lenticular lenses for high powers would be
Definition
they are lighter in weight
Term
a patient come back to the optician complaining of pain behind the ears possible  causes are
Definition

temple tension too great

uneven pressure

temple end pieces angled in too much

ALL OF TH E ABOVE

Term
what type of frame may be heated until it bends under its own weight
Definition
optyl
Term
the step fro finishing a lens (in correct are )
Definition
calculation spotting centeration blocking edging
Term
why is it necessary to take the B measurement
Definition
vertical decentration  
Term
for every 2 degrees of pantoscopic tilt the optical center should be
Definition
lowered 1 mm
Term
usual reading level is considered to be ? below
Definition
8mm
Term
a bifocal wearer having difficulty accommodating could most ofter be helped by adding ? to his prescription
Definition
a plus power
Term
which of the following is essential to place a prescription
Definition

lens prescription

frame name size and color

customers fitting dimensions

ALL OF THE ABOVE

Term
excessive up prism
Definition
makes people feel like they are walking downhill
Term
which statement is correct
Definition
polycarbonate lenses block UV radiation
Term
a number 3 tint is absords
Definition
80%of the light entering the lens
Term
a lens is AR coated to
Definition

increase transmission

reduce reflection

increase vision

Term
a patient complains that his old glasses have better visual acuity than the new glasses (same RX)what should an optician do ?
Definition
check the base curve
Term
a patient complains of too much pantoscopic tilt .what should the optician do
Definition
angel the temples upward from the endpieces 
Term
a patient with a perscription should wear a small frame to minimize
Definition

decentration

thinkeness

weight

ALL  OF THE ABOVE

Term
what shape frame should be worn by high minus power
Definition
rounded corners
Term
active people should wear what type of temple
Definition
comfort cable or riding bow
Term
people that have glasses on and off should wear ? types temples
Definition
library
Term
within the first few minutes of contact with a new patients
Definition
generate in the patient confidence in your ability
Term
what can you expect medicare to cover
Definition
corrective lenses following cataract surgery
Term
diopter is
Definition

1m 

 

and 1m is

100cm

1000mm

40in

Term
prism tolerance in the vertical meridian is
Definition
1/3 prism diopter
Term
as a general rule patient tolerance for prism imbalance in horizontal meridian is
Definition
2/3 prism diopter
Term
the cylinder axis tolerance for a 0.25D cylinder is
Definition
7degress
Term
the cylinder axis tolerance for a 0.75D cylinder is
Definition
5 degrees
Term
the cylinder axis tolerance for a 1.00D cylinder
Definition
3degrees
Term
the cylinder axis tolerance for a 2.00D cylinder is
Definition
2degrees
Term
the tolerance for lens thickness when specified for special prescription purposes is
Definition
+/- .3 mm
Term
the segment location tolerance in vertical (segment  height )meridian in a mounted
Definition
pairs should match within 1.0mm of specification
Term
lens calipers are used to measure lenses for
Definition
lens thickness
Term
the prism measurement indicator found in a lensometer is called
Definition
reticle
Term
the  instrument that can help you determine a heat temperd glasslens or stress in the lens is
Definition
polariscope
Term
line axis pliers are used fro purpose of
Definition
strightening lens axis in zyl frames
Term
glass lenses for stander use must with stand
Definition
5/8inc steel ball dropped from a height of 50inc
Term
plastic frame materials
Definition

zylonite/zyl orignally the most used material for plastic frames

cellulose propionte can be made thinner and lighter then zly

nylon lightweight hypollergenic and relatively unbreakable (good for sport wear gl)

rubber sometimes used for sport eyewear and sungl

carbon fiber adding carbon power gives plastic frame the streng5h of mental frame while keeping them lightwight

polyamide/copolymideblend of nylon that features durability reduced weight and flexbility considered hypo allergenic (never place in salt pan ,shinkage occurs when heated,dont clean with isoproply alcohol or products containing alcohol)

opty opty is considered thermoelastic has memory

kevlar also used for bullet prof vests and sports equlpments because of high tensile strength

polycarbonate reduced weight and fixibity hold translucent color well highly scr resistast

cellulose nitrate the first plastic uses it is flammable and unstable it is no longer used

Term
frame material plastic
Definition

zylonite /zyl orginally the most used material for plastic frame

cellulose propionate can be made thinner and lighter then zly

nylon lightweight hypoallergenic and relatively unbreakable (especially effective for sports and safety frame )

robber sometime used sports eye wear and sunglasses

carbon fiber adding carbon power gives plastic frame the straight of mental frame while keeping them light wight

polyamide/copolyamide blend of nylon that features durabilty reduced weight .flexibility considered hypo-allergenic ,never place poly amide frame in salt pans shrinkage occurs when heated ,don't clean with isopropy alcohol or products containing alcohol

opty  opty is considered thermoplastic has memory

kevlar also used for bullet proof vest and sports equlpment because high tensite strength

ploycarbonte reduced weight and flexibility holds translucent color well and highly scratch resistant

cellulose nitrate the first plastic used it is flammable and unstable (no longer used )

Supporting users have an ad free experience!