Geometry of Image Formation

Pinhole camera

The focal length is the distance from the pinhole to the image plane. The size of the projected image $(x,y)$ is related by the focal length $f$ and the distance to the pinhole $Z$.

$$x = f*\frac{X}{Z}$$

$$y = f*\frac{Y}{Z}$$

Rays captured by a lens converge on a focal plane. The distance from the lens to the image plane is twice the distance from the lens to the focal plane.


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