Color & Light Notes
Table of Contents
page#
1,2
Light Vocabulary
Electromagnetic
Spectrum
3
The Eye
4
Lenses and Mirrors
5,6
Color
7
Telescopes
8
Light Vocabulary
Photon - "packet of energy" released by an electron when it moves to another energy level in an atom.
Frequency - number of waves produced in a given amount of time.
Amplitude - maximum distance a wave vibrates from the rest position.
Transverse wave - a wave in which the particles of the wave's medium vibrate perpendicular to the
direction the wave is traveling.
Light energy - the energy produced by the vibrating electrically charged particles.
Electromagnetic Spectrum - the entire range of electromagnetic waves.
Radiation - the transfer of energy through matter or space as electromagnetic waves, such as visible
light and infrared waves.
Reflection - the bouncing back of a wave after it strikes a barrier or an object.
Law of reflection - the law that states the angle of incidence is equal to the angle of reflection.
Absorption - the transfer of energy carried by light waves to particles of matter.
Scattering - the release of light energy by particles of matter that have absorbed energy.
Refraction - the bending of a wave as it passes at an angle from one medium to another.
Diffraction - the bending of waves around a barrier or through an opening.
Interference - a wave interaction that occurs when two or more waves overlap.
Transmission - the passing of light through matter.
Transparent - the term describing matter through which light is easily transmitted.
Translucent - the term describing matter that transmits light but also scatters the light as it passes
through the matter.
Opaque - the term describing matter that does not transmit any light.
Pigment - a material that gives a substance its color by absorbing some colors of light and reflecting
others.
Luminous - the term that describes objects that produce visible light.
Illuminated - the term describing visible objects that are not a light source.
1
Incandescent light -light produced by hot objects.
Fluorescent light - visible light emitted by a phosphor particle when it absorbs energy such as
ultraviolet light.
Neon light -light emitted by atoms certain gases, such as neon, when they absorb and then release
energy.
Vapor light - light produced when atoms combine with gaseous metal atoms.
Plane mirror - a mirror with a flat surface.
lens - a curved transparent object that forms an image by refracting light.
Concave mirror/Iens - a lens or mirror that is thinner in the middle than at the edges.
Focal point - the point on the axis of a mirror or lens through which all incident parallel light rays are
focused.
Convex mirror/Iens - a lens or mirror the is thicker in the middle than at the edges.
Cornea - a transparent membrane that protects the eye and refracts light.
Pupil - the opening to the inside of the eye.
Iris - the colored part of the eye.
Retina - the back surface of the eye.
Laser - a device that produces intense light of only one wavelength and color.
Hologram - a piece of film on which an interference pattern produces a three-dimensional image of an
object.
2
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EM Spectrum
Radio
Microwaves
Infrared
Visible
Ultraviolet
X-Rays
Low Energy
Gamma Rays
High Energy
Low Frequency - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -High Frequency
Long Wavelength ---------------------------------------------------------------
3
Short Wavelength
Parts of the Eye
DIIAGRA.M O'F THE EYE
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Parts of the eye and their function:
Iris - the part of the eye that controls the size of the pupil.
Pupil- the opening in the eye that light passes through to the inside of the eye.
Lens - a curved transparent object that forms an image by refracting light.
Cornea - a transparent membrane that protects the eye.
Retina - the back surface of the eye where light and images are focused.
Vitreous Humor - clear gelatinous matter that fills the section between the retina and the lens.
Sclera - tough, white, outer layer of the eyeball that covers everything except the cornea.
Optic Nerve - either of two sensory nerves connecting the retinas of the eyes with the brain.
4
Lenses and Mirrors
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Color
Primary colors of light - red, blue, and green
Primary colors of pigments - cyan, magenta, and yellow
Transmission - is the passing of light through matter.
Transparent - matter through which light is easily transmitted.
Translucent - matter through which light passes but is scattered.
Opaque - matter that does not transmit any light. (ie. Solid)
Color Addition - when colors of light combine, more wavelengths of light are present.
Color Subtraction - each pigment absorbs at least one color of light. When you mix more colors of
pigments together, more colors of light are absorbed, or subtracted.
Pigment - a material that gives a substance its color by absorbing some colors of light and reflecting
others.
7
Telescopes
Eye;pieca
Reflecting
Light
G
(b)
a. Refracting Telescope - a refracting telescope uses a pair of convex lenses to gather and focus light.
b. Reflecting Telescope - a reflecting telescope uses a concave mirror, flat mirror, and lens to collect
and focus light.
Parts
F - Double Convex Lens
G - Concave mirror .
H - Plain (flat) mirror
Eyepiece - focus
8