LIGHT!
REFLECTION Every object sends light to your eyes. Some can produce its own light – sun, light bulbs, candles, fireflies, fish, lightening. This is called luminescence. Other objects take the light that’s produced and reflects it in certain wavelengths. To model light’s path, we use light “rays” to represent light traveling through space. The particles of light are called PHOTONS!
TYPES OF REFLECTION Diffuse reflection – reflection off of a bumpy surface Smooth surface reflection – reflection off of a smooth surface
MIRRORS Mirrors that bulge = convex (the outside of a spoon) (like funhouse mirrors)
Mirrors that indent = concave (the “caved in” side of the spoon)
The image we see from a regular mirror is called the VIRTUAL IMAGE – an image that forms at a point from which light rays appear to come but do not actually come The REAL IMAGE is an image of an object formed by many light rays coming together in a specific location
COLOR Color is produced because light produces different wavelengths. The color we see on an object is the wavelength that is reflected off of the object. All other wavelengths (colors) are being absorbed.
REFRACTION Refraction is what happens when light waves pass from one medium to another. When this happens with light, many times you see a MIRAGE.
LIGHT MOVING FROM AIR TO GLASS light ray bends inward (towards the “normal”)
LIGHT MOVING FROM GLASS TO AIR light ray bends outward (away from the “normal”)
THE EYE If the lens refracts light differently, nearsightedness or farsightedness results. Nearsighted – can’t see far (myopia) Farsighted – can’t see near (hyperopia) These result in needing corrective lenses
Nearsighted people have lenses in their eyes that focus light in front of the retina. They need DIVERGING LENSES (bends light outward) Also called concave lenses
Far sighted people have lenses in their eyes that focus light behind the retina. They need CONVERGING LENSES (bends light inwards). Also called convex lenses
Physiology of the Eye (3 min) Light: Visible and Invisible (6 min)