When an object is located outside the sphere center of a concave spherical mirror, it becomes an inverted and reduced real image, which is located between the focus and the sphere center; when the object is located between the focus and the sphere center, it becomes an inverted and enlarged real image, which is located outside the sphere center; when the object is located within the focus, it becomes an upright and enlarged virtual image, which is on the other side of the mirror. This software can help users calculate the focal length. The software is easy to operate. The interface is concise and worth using.
