Lens Distortion, Radial Distortion

Related Concepts

Camera Calibration; Lens Distortion, Radial Distortion

Definition

Lens distortion is a form of optical aberration that causes lenses to deviate from rectilinear projection. Commonly, it is caused by defects in lens design and manufacturing.

Background

In many cameras, optical errors or the construction of the lens by nature itself does not allow for rectilinear projection (projection that maps 3D lines onto 2D lines). The deviation from rectilinear projection is termed lens distortion.

In most common lens systems designed for rectilinear projection, this occurs because of optical errors and is primarily radial in nature. This phenomenon, also called radial distortion, is of two types: barrel distortion (Fig. 1) and pincushion distortion (Fig. 2). In barrel distortion, image magnification increases nonlinearly with distance from the optical axis resulting in lines “bulging outward.” Pincushion distortion has the opposite effect (lines bend radially inward), caused by...