image formation in lens

Objectives:

Compare the object and image in terms of

a. size

b. location from the lens

c. orientation

d. type

Objectives:

1. Locate the image in a lens through ray diagram.2. Describe the image in terms of

a. size b. location from the lensc. orientation d. type

Rules1. Any incident ray traveling parallel to the principal axis of a converging lens will refract through the lens and travel through the focal point on the opposite side of the lens.

2. Any incident ray traveling through the focal point on the way to the lens will refract through the lens and travel parallel to the principal axis.

2F F F’ 2F’

OBJECT OUTSIDE 2F

IMAGE: between F’ and 2F’, smaller, inverted, real

2F F F’ 2F’

OBJECT: BETWEEN 2F and F

IMAGE: OUTSIDE 2F’ and F’, bigger, inverted Real

2F F F’ 2F’

OBJECT AT 2F

IMAGE: AT 2F’, same size, inverted, real.

2F F F’ 2F’

OBJECT at F

IMAGE: No image

2F F F’ 2F’

OBJECT between F and lens

IMAGE: INFRONT of the lens, bigger, UPRIGHT, VIRTUAL

IMAGE: Just a point, Real and Inverted

OBJECT: at INFINITY

OBJECT: At any point.

IMAGE: smaller, upright, virtual.

OBJECT LOCATION IMAGE DESCRIPTION

CONVEX LENS

OUTSIDE 2F

AT 2F

BETWEEN F and 2F

AT F

BETWEEN F and LENS

AT INFINITY

CONCAVE LENS

At any distance from the lens

Between F’ and 2F’, smaller, inverted, real

At 2F’, same size, inverted, real

Outside 2F’, bigger, inverted, real

No image

In front of the lens, bigger, upright, virtual

In front of the lens, bigger, upright, virtual

In front of the lens, bigger, upright, virtual

Assignment:

1. What are the equations in solving problems about lens?

2. Bring scientific calculator