Magnifying Glass Magic: How Does It Work?
How does a simple magnifying glass create an image?
When a magnifying glass is used to magnify ... for example, to inspect the markings on a dime, or to read the fine print in an insurance policy ... no image is formed. That is, no real image. What type of image is actually formed?
Answer:
A simple magnifying glass creates a magnified virtual image by making the image subtend a larger angle on the eye than the object does when viewed without the lens.
When a simple magnifying glass, which is a converging lens, is used properly, the image formed is virtual, upright, and larger than the object. This occurs when the object is placed within the focal length of the lens. The magnified virtual image is produced because the image produced by the lens subtends a larger angle on the eye compared to the object without a lens, resulting in the perception of a larger image.
This angular magnification is the ratio of the angle subtended by the image to that subtended by the object when viewed without the magnifying glass.