A multi-component system whose aperture stop is located at the front focus so that the chief rays are parallel to the optical axis in image space. For a telecentric lens, the exit pupil is at infinity.
A lens in which the aperture stop is located at the front focus, resulting in the chief rays being parallel to the optical axis in image space (i.e. the exit pupil is at infinity). This results in the apparent size of the object not changing with focus. A true telecentric lens maintains a constant viewing angle at any point across the clear aperture of the objective lens allowing the machine vision system to generate dimensionally accurate images for measurement.
Lens in which the exit pupil is at infinity. Applied, this means that within a certain range of working distances there is no viewing angle error or magnification error associated with features in the image that are at different heights or angles.
A lens that provides constant magnification at any object distance. They make accurate dimensional measurements over a larger range than conventional lens. Also, telecentric lenses view the whole field form the same perspective. Thus, a deep round hole looks round at the top and bottom of the hole.
Compound lens with an unusual property concerning its geometry of image-forming rays. In machine vision systems telecentric lenses are usually employed in order to achieve dimensional and geometric invariance of images within a range of different distances from the lens and across the whole field of view.
A telecentric lens is a compound lens with an unusual property concerning its geometry of image-forming rays.