Lecture 6: Telescopes

which telescope is for higher powers (3x-14x)...keplarian or galilean

keplarian

where is the exit pupil located in keplarian telescope

outside

where is the exit pupil located in galilean telescope

inside

is the ocular lens pos or neg in keplarian telesscope

positive

is the ocular lens pos or neg in galilean telesscope

negative

which one has a wider FOV, keplarian or galilean

keplarian

which telescope will show an img blurry at the edges?

galilean

which telescope shows the img sharp from edge to edge

keplarian

is the image more bright in a keplarian or galilean telescope?

galielan

if BCVA is 20/160 and the goal is 20/40, what telescope mag to rx?

160/40 = 4x

does a lower powered telescope have a bigger or smaller FOV?

bigger

who is a telescope in reverse useful for?

pts who already have good acuity

if a myope is uncorrected, what happens to mag when looking through a keplarian telescope

increased mag

if a myope is uncorrected, what happens to mag when looking through a galilean telescope

decreased mag

if a hyperope is uncorrected, what happens to mag when looking through a keplarian telescope

decreased mag

if a hyperope is uncorrected, what happens to mag when looking through a galilean telescope

increased mag

equation for img brightness

img brightness = exit pupil area / eye pupil area

the bigger the pupil, the _ the image will appear

brighter

do nystagmus pts do well w telescopes?

yes

nystagmus pts use their _ when looking through telescopes

null point

what are Eschenbach MaxTV glasses

distance magnifying glasses

good for low mag

spectacle mounted telescopes work well for pts w _ refractive error

high

equation for telescope mag equivalent power

TM equiv power = telescope mag x reading cap

reasons to not rx a telescope

poor CS

poor VA

constricted VFs

unrealistic expectations

what is normal CS

1.7 weber log units