Conventions and beam vergence Flashcards
Cartesian Sign Convention (right, left)
Right (+), Left (-) Object location, image location, focal length, radius of curvature
Cartesian sign convention (up, down)
up (+), down(-) Object height, image height
magnification
ratio of image height to the corresponding object height
M
image smaller
M>1
larger
M=1
no size change
minus magnification
inverted
plus magnification
upright
What are the units of magnification
no units
longitudinal magnification
ratio of image length, image length over object length
angular magnification
How big it appear
Virtual Object
Rays converge to, after the optical element
Real object
Rays originate from it, before the optical element
Real Image
Rays converge to it, After the optical element
Virtual Image
Rays originate from, before the optical elelment
What is the most critical parameter in optics
Beam Vergence. the inverse of the distance required to converge to a point
convering
+
Diverging
-
diopter
inverse of a meter 1/m
distance to focus
the larger the distance, the smaller the vergence. units m
vergence
units: diopters. the larger the distance the smaller the distance to focus
What is the property for changing mergence of beam?
optical power
What does NOT change the vergence?
plane
What kind of power does a lens have?
optical power, can bend and disperse beams
