Convex lens – object at `2F`
This means the object is two principal focal lengths from the convex lens.
A ray diagram can be constructed using the two standard rules
- From the object, pass a parallel line through the principal focal point
- From the object, pass a ray line through the centre of the convex lens.
We can see that when the object is two principal focal lengths from the convex lens, the image can appear on a screen exactly at two principal focal lengths on the other side of the lens. The image will be inverted but can be captured on a screen.
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