Optical Prescribing Considerations Flashcards
3 types of Progressive lens.
Standard
Short corridor length
Variable corridor length
Short corridor length type of PAL
Minimum fitting height is 10mm to 14mm
Standard corridor type of PAL
Normally classified as being 15 mm to 18 mm minimum fitting heights
Variable PAL type
Based on several factors including frame design, power, position of wear
The longer the corridor length the ______ (wider/narrorwer) the corridor and _____ (more/less) unwanted peripheral astign
Wider
Less
The shorter the corridor length the _____ (narrower/wider) corridor and _____ (more/less) the unwanted peripheral astigma
Narrower, more
The higher the add power_____ (higher/lower) the unwanted peripheral astignma
Higher
You cannot confidently recommend the correct computer lens without knowing their …….
Working distance
If your pt is spending more than ____ hours a day on computer, recommend a computer lens in addition to their standard lens.
4 hours
Which type of lens is best for computer lens
FT bifocal,
What type of computer or office lens are out there
Which is best for wide dual monitors
FT Bifocals, single visions
Bifocals best for wide dual monitors
In a varilux computer lens how much of the add power is the intermediate power
60%
Computer lens can come in three ranges. T/f
True
Near, intermediate, distance
Hoya tract puts their design on the front or back?
Back.
There’s two designs: 40% of total reading power in intermediate or 60% of total reading power in intermediate.
What’s the difference between computer lens and anti fatigue lens?
Computer lens we recommend if they are using the computer more than 4 hrs a day. We add a wider intermediate zone with a certain percentage of add power. Computer lens are good for presbyopes.
Anti fatigue lens are good for the non presbyopes. Teens, young adults. People who are not presbyopia and are contantly using hand held tablets, phones, and laptops. They do pretty well with these because they can still accommodate pretty.
