The thin lens equation shows that when there is an object further than the focal point, there is a real image formed on the other side of the lens, and this principle is used for cameras, eyes, etc.
However, when I take a converging lens(that I got from some mobile VR headset), and hold it between me and an object, both of whom are more than the focal length away from the lens, I see an upside-down virtual image of the object.
So my question is, why do I see a virtual image instead of a blur that I would see at the point where the real image forms? What would the ray diagram look like for this?
Here is a picture of this phenomenon:
Best Answer
A converging lens (convex lens) will always create a real inverted image if the object is located at a point beyond the focal point (at a place on the opposite side of the lens). The only exception to this, is if the object is closer (to the lens) than the focal point is to the lens, in which case the image will appear to be on the same side of the lens as the object and the image will be a right side up and it will be a virtual image.
Just because you are not seeing the image at the exact point where the rays converge, does not mean it is a virtual image. This just means that image is out of focus.