Basic Prism And Characteristics Of Opthalmic Lenses Flashcards
When light strikes a prism, the light Ray is bent (deviated) toward the——, and the image is displaced toward the—-
Base / apex
How far will 2 prism diopters deviate light at 1 M?
2 CM
When light passes from a medium of lesser density, such as air to a medium of greater density, such as glass, the path of the light is bent toward the——
Normal
Some characteristics of plus lenses include:
Magnifies images, converge images, power weakens as vertex shortens
Some characteristics of minus lenses include:
Minifies images, diverges images, power strengthens as vertex shortens
Which lens would produce with motion?
Minus
Which lens would produce against motion?
Plus
Compound lenses (Sphero-cylinder lenses) combine a spherical surface with a ——
Toric or cylindrical surface
The principles meridians on a compound lens are——-
90 degrees apart
Plus cylinder lenses————
Have the cylinder generated on the front surface
Minus cylinder lenses———
Have the cylinder generated on the back surface
Where would the full cylinder power be located on this Rx? -1.00 -1.50 X 045
135 degrees
Where would the full cylinder power be located on this Rx? -1.00 -1.50 X 090
180 degrees
Where would the thickest edge be located on this Rx? -1.00 -1.50 X 135
045 degrees
Where would the thickest edge be located on this Rx? -1.00 -1.50 X180
090 degrees
