c'est quoi la lumiere?

une forme d'energie - lumineuse

types de lumiere

phosphorescence

fluorescence

bioluminescence

chimioluminescence

incandescence

fluorescnece

absorbe les particules uv et emet sous forme de lumiere

bioluminescence

light that comes from living things

chimioluminescence

lumiere emi a cause d'une reaction chimique

incandescence

light emitted because of heat

phosphorescence

absorbs the light and then emits it later (like the paint on car buttons)

sources de lumiere

chimique

naturel

artificiel

things that use light

microscope

loupes

lentilles portatifs

proprietes de lumiere

light travels in a straight line

light travels in waves

light refracts

light reflects

electromagnetic spectrum

gamma rays

x rays

uv rays

visible light

infrared

microwaves

radio waves

what happens to light when it hits something opaque

the rays bounce off (some get absorbed)

what happens to light when it hits something translucid

some go through, some bounce off

what happens when light hits something transparent

the rays go directly through it

parts of a reflection

normale, angle d'incidence, angle de reflexion, rayon d'incidence, rayon de reflexion

concave mirror

curved inwards, makes the light rays converge

convex mirror

curved outwards, makes the light rays diverge

refraction

the bending of light due to change in density

more dense substance to less dense substance

light refracts away from the normale

less dense substance to more dense substance

light refracts towards the normal

mirages

since light refracts, changes in density can make the light bend so you think something is closer

concave lens

curved inwards, makes the rays diverge

convex lens

curved outwards, makes the rays converge

nearsightedness / myopia

concave LENS

farsightedness / hypermyopia

convex LENS

lens/mirrors: microscopes

lenses

lens/mirror: binoculars

prisms/lenses

lens/mirror: refracting telescopes

lenses

lens/mirror: reflecting telescopes

mirrors

how the eye works

light enters the eye through the cornea and pupil, reaching the lens which is bent by the muscle ciliaire. the light is then refracted to converge at the retina, where batonnets and cones respond to the light level and colours. the invformation then travels to the brain by the optic nerve. the brain flips the image it receives, as when the light converges at the retina it also flips the image.

circular pupil eyes

depth perception, but less field of vision - predator

horizontal pupil eyes

this prioritizes vertical field of vision - predator

vertical pupil eyes

prioritizes depth perception close to the ground - predator

horizontal pupil eyes (not curtain like)

prioritizes a large field of vision

why can birds see tiny things far away?

their muscle ciliaire can bend their lens so much to focus on things very far away

how does a laser work?

rays of light reflect inside the laser to give it more energy, and then exit through one side that is very slightly translucid (2%) to make a concentrated beam of light

laser eye surgery steps

1 - peel off the top part of your eye

2 - shave off a small piece of your cornea ( changes the shape )

3 - changes the focus of your eye

nocturnal imagery

intensifies the light that it absorbs

infrared imagery

detects heat, and then makes an image out of information they get from each point of the area