thick and thin lenses

Define a lens

an image forming device

Define an Equi-convex lens

a lens which has the same radius of curvature on both surfaces

Define a double/bi-convex lens

a lens which has two different radiuses of curvature

Define a plano-convex lens

a lens which has one plane surface and one curved convex surface

Define a convex meniscus lens

two curved spherical surfaces concave on one side and convex on the other

what does f (little f) represent

focal length

What does F represent ( capital F)

principal focus point

what does n represent

Lens material refractive index

when the object positioned beyond twice the focal length what happens to the image

• image is between f and 2f on the opposite side

• image is real and inverted

• size of the image is reduced

when the object is positioned at 2x the focal length what happens to the image

• image is positioned at 2f on the opposite side

• image is real and inverted

• image size is the same

when the object is positioned between f and 2f what happens to the image

• image is beyond 2f on the opposite side

• image is real and inverted

• image is magnified

when the object is at 2f what happens to the image

no image is formed

when an object is inside the focal length what happens to the image

• image is further away on the same side

• image is virtual and upright

• image is magnified

what does a positive focal length indicate

a converging lens

what does a negative focal length indicate

a diverging lens

what is the lens maker equation

1/f = (n−1)(1/R1 − 1/R2)

f is the focal length (half the radius of curvature)

n is the refractive index of the material used

R1 is the radius of curvature of sphere 1

R2 is the radius of curvature of sphere 2