Light and Optical Systems: Topics 4-5 Flashcards
Concave
A lens that is thinner and flatter in the middle than around the edges, causing the refracting light rays to diverge or spread out.
Convex
A lens that is thicker in the middle than around the edges, causing the refracting light rays to converge or come together
Near-sighted
Eyes are too long, image forms in front of the retina. Have trouble seeing distant objects. Vision is corrected with concave lens.
Far-sighted
Eyes are too short, images do not form by the time the light reaches the retina. Have trouble seeing close up objects. Vision is corrected with convex lens.
Optic nerve
Connects the eye to the brain, sends signals from the eye to the brain
Retina
Light sensitive area at the back of the eye. Forms images from light
Vitreous Humour
Gel like substance that fills the space in between the lens and the retina of the eye. Allows the eye to keep it’s shape
Ciliary Muscles
Muscle in the eye that focuses/controls the lens
Lens
The film or material that focuses the light onto the retina
Aqueous Humour
A clear fluid that fills the space between the cornea and the lens.
Cornea
Transparent front part of the eye that covers the iris and pupil. It helps refract light
Iris
Coloured ring, works like the diaphragm of a camera
Pupil
The opening of the eye, appears as a dark circle. Let’s light in
Refracting telescope
A telescope having a convex lens to collect and focus light from a distant object and an eye piece lens to magnify the image
Objective lens
A convex lens in a refracting telescope or microscope
