- Concave Mirror Ray Diagram lets us understand that, when an object is placed at infinity, a real image is formed at the focus. The size of the image is much smaller compared to that of the object.

When an object is placed behind the center of curvature, a real image is formed between the center of curvature and focus. The size of the image is smaller than compared to that of the object.

When an object is placed at the center of curvature and focus, the real image is formed at the center of curvature. The size of the image is the same as compared to that of the object.

When an object is placed in between the center of curvature and focus, the real image is formed behind the center of curvature. The size of the image is larger than compared to that of the object.

When an object is placed at the focus, the real image is formed at infinity. The size of the image is much larger than compared to that of the object.

When an object is placed in between focus and pole, a virtual and erect image is formed. The size of the image is larger than compared to that of the object.

Summary
S. No | Position of Object | Position of Image | Size of Image | Nature of Image |
1 | At infinity | At the focus F | Highly Diminished | Real and Inverted |
2 | Beyond the center of curvature C | Between F and C | Diminished | Real and Inverted |
3 | At the center of curvature C | At C | Same Size | Real and Inverted |
4 | Between C and F | Beyond C | Enlarged | Real and Inverted |
5 | At focus F | At Infinity | Highly Enlarged | Real and Inverted |