1. The image formed by a lens
A converging lens can form a real image (can be projected on a screen) or a virtual image (e.g. a magnifying glass).
In a real image, light rays from the object actually come together.

2. Rules for drawing ray diagrams
These are the rules for how light rays are bent by the lens:
Parallel Ray (red): a light ray parallel to the axis refracts through the far focal point (principal focus).
Centre Ray (blue): A light ray passing through the center of the lens is not refracted at all.
Focal Ray (green): A light ray passing through the secondary focus refracts parallel to the axis.

3. Drawing a Ray Diagram Draw Ray 1
Draw Ray 1 (parallel  principal focus)
Principal Axis
Principal Axis
Draw Ray 2
Draw Ray 2 (through optical centre)
Draw Ray 3
Draw Ray 3 (secondary focus  parallel)
Principal Axis
Principal Axis

4. Principal Axis

5. Describing Images with SALT
A ray diagram is a way to understand:
whether the image is bigger, smaller or the same size as the object (Size)
whether the image is upright or inverted (Attitude)
where the image is (Location)
and whether the image is real or virtual (Type)

6. Principal Axis

8. PRACTICE!
Complete Example 2 on your worksheet, and check in with Ms. Pasic.
Complete Ray Diagram practice on your worksheet
Page 561 Questions 1, 2,iv 5, 6
Review tomorrow’s lab assignment sheet.