Fisheye Camera

A camera with an ultra-wide fisheye lens, often around 180° field of view, whose images bow visibly at the edges.

A fisheye camera uses an ultra-wide-angle fisheye lens, typically with a field of view of 100° to 180°, sometimes more. Unlike an ordinary lens, which keeps straight lines straight, it maps the scene through a specific projection (equidistant, equisolid-angle, and others) to compress a very wide view into one image, giving the image a convex, barrel-like distortion; the term ‘fisheye’ was coined by the physicist Robert W. Wood in 1906. The ordinary pinhole model can't describe distortion this severe, so calibration needs specialized models, such as the equidistant, double-sphere, and omnidirectional models supported by the Kalibr toolbox. Two uses are common in robotics: visual SLAM and panoramic sensing use fisheye lenses to widen the field of view and reduce tracking loss, while wrist cameras use them to add close-range environmental context — the UMI paper notes that a fisheye lens preserves resolution at the center of the image while compressing peripheral information into the frame.

ExampleUMI's handheld gripper adds a 155° fisheye lens to its wrist-mounted GoPro, so that even when the gripper gets close to an object, enough of the surrounding tabletop is still visible in frame.

Also called

Wide-Angle Camera, Fisheye Lens

Related

Field of View · Lens Distortion · Camera Calibration · Universal Manipulation Interface · Wrist Camera · Visual SLAM

Sources

Fisheye lens - Wikipedia
Kalibr: Supported camera and distortion models
Universal Manipulation Interface (arXiv:2402.10329)