optics test - 4/22/24 Flashcards
for optics test on april 25; not all topics of test included
what is incandescence?
occurs when objects that are heated to high temperatures emit light. colours change with temp. examples include burning candles.
what type of light emission is produced when electric currents pass through gasses, causing them to glow?
electric discharge; examples include lightning and neon signs
what is fluorescence?
when objects emit light immediately after absorbing ultraviolet light. examples include laundry detergents, highlighter pens, etc…
what is phosphorescence?
when materials absorb ultraviolet (UV) light and emit it over time (ex: glow in the dark objects)
what is chemiluminescence?
Light produced as a result of a chemical reaction without producing heat. (ex: light sticks + glow sticks)
what is bioluminescence?
Chemiluminescence in living organisms (ex: certain bacteria, glow worms, fish)
what is triboluminescence?
light produced from friction with crystals, first observed by francis bacon
what is light-emitting diodes (LEDs)?
electronic devices that emit light when electric currents pass through them, more energy efficient than incadescent bulbs, used in things like traffic lights and christmas lights
what is the cornea?
clear tissue that refracts light; makes it go into eye
what is the lens?
focuses the image that cornea creates by fine tuning it
what are the ciliary muscles?
muscles that assist in the process of focusing the image (lens’ job) – they change the shape of the lens
what is the pupil?
entrance that allows light enter the eye
what is the iris?
controls size of pupil (coloured part of eye)
what is the retina?
screen that images are projected into; located in abck of eye
what is the optic nerve?
sends messages to the brain about what is seen by being the receptors in the retina