IGCSEPhysicsCambridge (CIE)Revision Notes3. WavesLightVirtual Images

Virtual Images (Cambridge (CIE) IGCSE Physics): Revision Note

Exam code: 0625 & 0972

Written by: Katie M

Reviewed by: Tim

Updated on 7 September 2026

Converging lens - virtual image

Extended Tier Only

Constructing converging ray diagrams of virtual images

A single lens placed at a distance less than the focal length of an object can be used as a magnifying glass

A converging lens ray diagram for an object placed less than f

Diagram showing a frog viewed through a converging lens as a magnifying glass, with rays spreading out to form a larger upright virtual image. — **Ray diagram showing light converging through a magnifying glass to form a magnified virtual image**

The image that forms will have the following properties:

The image forms...	at 2f (on the same side as the object)
The nature of the image is...	virtual
The orientation of the image is...	upright
The size of the image is...	magnified

Diverging lens - virtual image

Image formation by a diverging lens

No matter the position of the object, all images formed by diverging lenses are:
- virtual (and not real)
- upright (the same as the object)
- diminished (smaller than the object)
- on the same side of the lens as the object
For an object placed at any distance away from the lens (further than the focal point or closer than):
- The ray of light incident on the centre of the lens does not change direction
- The rays of light parallel to the principal axis are refracted
- These rays can be extrapolated backwards
  - It appears that they come from a virtual focus
- A visible projection cannot be formed on a screen

Virtual image produced by a diverging lens with object beyond f

Ray diagram of a diverging lens forming an upright, reduced virtual image from an object placed beyond the focal length f, with focal points marked and an eye viewing the refracted rays. — **A diverging lens always produces a virtual image no matter the position of the object in relation to the focal point or the lens. Here the object is further away from the lens than the focal point.**

Virtual image produced by a diverging lens with object closer than f

Ray diagram of a diverging lens showing an upright diminished virtual image from an object placed inside the focal length f, with real and virtual rays traced from the object. — **A diverging lens always produces a virtual image no matter the position of the object in relation to the focal point or the lens. Here the object is closer to the lens than the focal point.**

Comparing converging and diverging lenses

The image produced by a converging lens can be either real or virtual
- This means the image can be inverted (real) or upright (virtual)

The image produced by a diverging lens is always virtual
- This means the image will always be upright

Worked Example

An object is placed outside the focal point of a diverging lens.

A diverging lens is shown at the centre of a graph. The focal points are located four grid squares left and four grid squares right of the diverging lens. An upright object is placed five grid squares left of the diverging lens.

Complete the ray diagram by drawing where the image of this object will be seen.

[3]

Answer:

$A diverging lens is shown at the centre of a graph. The focal points are located four grid squares left and four grid squares right of the diverging lens. An upright object is placed five grid squares left of the diverging lens. A ray is drawn from the top of the object towards the optical centre of the lens and is undeflected. A ray parallel to the principal axis is refracted outwards to the top right of the graph. The point at which the extension of this refracted ray intersects with the other ray is where the virtual image is formed.$

Step 1: Draw a line from the top of the object through the middle of the lens

The top of the image lies somewhere along this line [1 mark]

Step 2: Draw a line from the focal point through the top of the lens

The dashed line shows the continuation of the upward arrow [1 mark]
The top of the image is where the two lines cross [1 mark]

Examiner Tips and Tricks

You are not expected to draw ray diagrams for a diverging lens but you must be able to explain how the virtual images are formed.

Unlock more, it's free!

Join the 100,000+ Students that ❤️ Save My Exams

the (exam) results speak for themselves:

I would just like to say a massive thank you for putting together such a brilliant, easy to use website.I really think using this site helped me secure my top gradesin science and maths. You really did save my exams! Thank you.

Beth
IGCSE Student

This website is soooo useful and I can’t ever thank you enough for organising questions by topic like this. Furthermore, the name of the website could not have been more appropriate as it literally did SAVE MY EXAMS!

Fathima
A Level Student

Incredible! SO worth my money, the revision notes have everything I need to know and are so easy to understand. I actually enjoy revising! It makes me feel a lot more confident for my GCSEs in a few months.

Kate
GCSE Student

Absolutely brilliant, both my girls used it for A levels and GCSE. It's saves on paper copies, also beneficial exam questions ranked from easy to hard. It's removed a lot of stress from the exams.

Sameera
Parent

Just to say that your resources are the best I have seen and I have been teaching chemistry at different levels for about 40 years

Mark
Chemistry Teacher

Excellent