Light and Eye Flashcards
Light
A narrow band of electromagnetic radiation that can be conceptualized as a wave or a stream of photons.
Photon
A quantum a visible light demonstrating both particle and wave properties.
Light can be:
-Reflected, -Refracted, -Scattered, -Transmitted, -Absorbed
Name the different parts of the eye.
- Cornea
- Aqueous humour
- Pupil
- Iris
- Crystaline lense
- Vitreous humour
- Retina
Cornea
Transparent film into the eye ball
Aqueous humour
Watery fluid into the anterior chamber
Pupil
The dark circular opening at the centre of the iris that lets the light enter the eye.
Iris
The coloured part of the eye. It regulates the amount of light that enters the eye by expanding and contracting.
Crystalline lens
Lense inside your eye that focuses light onto the back of the eye.
Vitreous humour
Transparent fluid that fills the large chamber in the posterior part of the eye.
Retina
A light-sensitive membrane at the back of the eye that contains rods and cones.
The lens focuses an image on the retina, which then sends the signal to the brain through the optic nerve.
Accomodation
A process where the lens changes its shape to alter the refraction.
True or false,
Do nearby objects require more refraction?
True
True or false,
Do maximal accommodation decreases with age?
True
Diopter
Unit of measure of the focusing force of a lense
Focal length
Distance between the lens and the point where the points converge.
Name 5 eye conditions linked with problems of refraction:
- Emmetropia
- Myopia
- Hyperopia
- Presbyopia
- Astigmatism
Emmetropia
No sight problem
Myopia
Can’t see the distant objects and the focal point is before the retina.
Hyperopia
Can’t see the close objects and the focal point is behind the retina.
Presbyopia
A type of hyperopia due to old age
Astigmatism
Mal-formation of the curves of a part of the eye, usually the cornea. This leads to having many multiple focal points and some lines won’t seem to converge to a common point.
