What are some optical magnifiers for near vision?
What are spectacle magnifiers? Ads and Disads?
What are SV specs? What is the pwr range?
WHat are spec mounted “plus” lens magnifiers?
hand magnifiers ads and disads
Ads and Disads of stand magnifiers
What is this type of near magnifier called?
What is this type of near magifier called?
One optical magnifier for distance vision is a telescope. Ads and Disads?
What do the markings on a telescope mean?
mag= 4x
diameter of objective lens = 12
eyepiece lens diameter = objective lens diameter /mag = 200mm
What do markings on magnifiers mean?
3x12D
mag = before x = 3
power of lens = 12D
Difference between galilean and Keplerian telescopes?
Non optical ways to maximise visual performance
larger print
high contrast watch faces
kitchen aids eg, audible liquid level indicator & talking tins
raised line note paper
phones - big buttons
TV audio description
audio books
EVES - printed objectes put under a camera and maginifed image displayed on screen
Ads: adjustable FOV, portable
Disads: expensive, requires power supply, difficult on round objects
TV readers
Improve lighting in house - open curtains, avoid net curtains, paint walls in light colours, LED lighting
Braille
guide dogs
canes
Last changed13 days ago
