Transmission Of Light Through The Eye Flashcards
Function of dioptric apparatus
transmits and refracts visible light to focus it on the retina
Two types of refractive errors and what “causes” them
Myopia- elongated eyeball
Hyperopia- short eyeball/ cornea too flat
What is the protein making the main composition of the cornea
Collagen
What is the wavelengths absorbed by the cornea
Below 295nm
What wavelengths are absorbed by the lens
295-400nm
(Part of the UVB and full UVA)
What influences intraocular pressure
Rate at which aqueous humor is produced and drained away
What is presbyopia
Loss of accommodation
What is the range of wavelengths that humans can see as visible light
390-780nm
Why does you vision become blurred in water
The refractive index of water and the lens are almost similar
How does the pupil change its size in different light conditions
Bright light- pupil becomes smaller: sphincter muscles (encircles pupil) contract
Dim light- pupil becomes bigger: dilator muscles (radiates outwards from centre) contract
Which proteins densely packed in the lens are responsible for its high refractive index
Crystallin protein
3 main components of vitreous humor
Water
Carbohydrates called glycosaaminoglycans (GAGs)
Collagen
Types of Photoreceptors found in
1. Foveola
2. Fovea
3. Macula
- Foveola- cones only
- Fovea- cones and rods
- Macula- cones and rods
Give the diameters of 1. Macula
2. Fovea
3. Foveola
Macula- 5.5mm
Fovea- 1.5mm
Foveola- 0.35mm
What part of the infrared part of solar spectrum reaches the retina
700-1400nm
