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Refraction
The change of speed of light as it moves from one medium to a different medium
Refracted Ray
The light ray that changes its path after entering a new medium
Angle of Refraction
The angle made between the normal and the refracted ray
Refractive Index
The numerical value given to optical density. Can be calculated as a ratio of (sin i)/(sinr) OR as c/v
Optically Dense
A measure of how much light will slow down in a medium
Total Internal Reflection
The complete reflection of a light ray. Happens when the ray begins in the medium with the larger refractive index, and the angle of incidence is greater than the critical angle
Critical Angle
The angle after which total internal reflection will occur
Focus (Focal point)
The point light rays converge on after passing through a lens.
Principal Axis
Line that passes through the optical center of the lens
Focal Length
distance between the optical center and the focal point
Lens
A collectin of prisms, used to refract light
Optical Center
The middle of a lens
Upright
Position with the top on top, and the bottom on the bottom
Virtual Image
An image formed by the divergence of light rays
Laterally Inverted
Left-right switched
Real Image
An image created by the convergence of light rays.
Endoscope
A tool used by doctors to see inside of patients
Prism
A transparent tool used with light rays
Vacuum
A space that has no matter (including air)
Diverging Lens
A lens that sends light rays away from each other
Object distance
The distance between the lens and the object
Image distance
The distance between the image and the lens.
Boundary
The edge of separation between two things
Optical fiber
Thin glass or plastic that is used to transmit information by light
Magnified
Bigger
Diminished
Smaller
Inverted
Upside-down
Focal plane
The 2-D plane in which the focus lies