Real Image
An optical image formed by actual convergence of light rays, which can be projected onto a physical screen.
Governing formula
v > 0 (for real image), m < 0 (inverted)
SI unit
m
In depth
Real images are always inverted relative to the object. Formed by converging elements (concave mirrors, convex lenses) when object is outside focal length ($u > f$).
Examples in the real world
The inverted real image projected onto a cinema screen or camera digital sensor.