VISUAL PHYSICS ONLINE WAVES RAY MODEL OF LIGHT IMAGE FORMATION DIVERGING LENSES OPTICAL INSTRUMENTS

DIVERGING LENSES A diverging lens produces a virtual image since the rays of light do not pass through the image. Fig. 1. Diverging Lenses. N.B. The eye does not distinguish between real and virtual images both are visible. Fig. 2. A virtual image is formed by a diverging lens. the image is reduced in height and upright. The bright and dark patterns that seem to move across bottom of a swimming pool are a result of the surface of the water acting like a blanket of undulating lenses. Why stars twinkle has a similar explanation - the irregularities in the atmosphere produces the twinkling.

Thinking Exercise Compound Microscope

Study the ray tracing diagram of the microscope shown in figure 3. Write a careful explanation of how the microscope produces a magnified virtual image of the object.

Fig. 3. Compound microscope.

Thinking Exercise Telescope

Study the ray tracing diagram of the telescope shown in figure 4. Write a careful explanation of how the telescope produces a magnified virtual image of the object.

Fig. 4. Refracting telescope.

Magnificent magnified images

Computer simulation activity

Use the computer simulation to review your understanding of the formation of images using a converging lens or a diverging lens.

Check the numbers displayed in the simulation using the equations:

(2) lens equation (thin lens)

(3) lateral magnification

Lens simulation

You can only change the position of the focal point.

VISUAL PHYSICS ONLINE

If you have any feedback, comments, suggestions or corrections please email:

Ian Cooper School of Physics University of Sydney

ian.cooper@sydney.edu.au