Optics
Diverging lens — virtual image
A diverging lens always makes a reduced, upright, virtual image.
Diverging lens — virtual image — interactive Optics simulation. A diverging lens always makes a reduced, upright, virtual image. Free browser-based virtual physics lab with live SI measurements and a guided tutorial.
Diverging lens
A diverging lens always makes a reduced, upright, virtual image.
Diverging lenses (and convex mirrors) spread rays as if from a focal point behind the element. Every object distance yields a virtual, upright, smaller image. Eyeglasses for myopia exploit this to push the far point outward.
- Always virtual image
- m < 1 upright
Investigation brief
Plan the question before you open the lab
The brief mirrors the prerendered page: driving question, competing predictions, variable roles, governing laws, setup, analysis and extension prompts remain visible and in this order.
Driving question
A diverging lens has a negative focal length. Does it ever form a real, enlarged image, the way a converging lens can?
Predictions to weigh
- No — a diverging lens always forms a smaller, upright virtual image, no matter the object distance.
- It forms a real image when the object is far enough away.
- It always forms a real, enlarged image.
Variable roles
What you set:
- Object distance d_o (cm)
What you measure:
- Image distance d_i (cm)
- Magnification m
How the investigation runs
- Open the diverging-virtual preset and press Reset. The lens's focal length is fixed at −10 cm.
- Enable the image-distance and magnification readouts.
- Set the object distance for each trial and record the image distance and magnification.
Governing equation
Diverging Lens Imaging — dᵢ = dₒ·f/(dₒ − f)
A diverging lens has negative focal length. Substituting f < 0 into 1/f = 1/d_o + 1/d_i always yields negative d_i (virtual) and 0 < m < 1 (reduced, upright) for any positive object distance.
What the printable worksheet asks students to work out
- For one trial, compute d_i from 1/f = 1/d_o + 1/d_i using f = −10 cm, then m = −d_i/d_o. Compare both to the table.
- Explain why, no matter how large d_o gets, d_i stays negative (virtual) and m stays positive and less than 1 for a diverging lens — unlike a converging lens's behavior in the converging-real experiment.
Where this shows up beyond the lab
- A door peephole uses a diverging lens (or a similar wide-angle design) to show a reduced, wide field-of-view image of whoever's outside. Explain why a reduced image is exactly what you'd want for a peephole's purpose.
- As d_o grows very large (object very far away), what does d_i approach? Compare it to the lens's focal length, and explain physically why a diverging lens's virtual image can never move past its own focal point.
- AP Physics 2 — Unit 13: Geometric Optics
- General High School Physics — Light & optics
- NGSS High School Physics — Wave properties
- Welcome to Diverging Virtual
- Select the object
- Press Play
- Always virtual
- Open the Properties panel
- You did it!
Open the interactive simulation to build the scene, press Play, and explore with live measurements and a guided tutorial.