Patent ID: 8081297
Filing Date: 2011-12-20
Classification: G01B,G01C,G01S

Abstract:
1. A laser tracker that digitizes an image of a target, comprising: a structure rotatable about a first axis and a second axis, the structure including a first optical system and at least a portion of a distance meter, wherein the distance meter launches a beam through a portion of the first optical system to the target, the distance meter configured to measure a first distance from the laser tracker to the target based at least in part on the speed of light; a position detector that collects from a portion of the first optical system a portion of the beam reflected by the target; a first electronics system that causes the beam to track the target based at least in part on a signal from the position detector, wherein the tracking is obtained by rotating the structure about the first axis and the second axis; a first encoder that measures a first angle of rotation about the first axis; a second encoder that measures a second angle of rotation about the second axis; a second optical system that forms the image of the target on a photosensitive array, the second optical system having a transverse magnification and including, on an optical axis, a plurality of lens elements, the lens elements including a first lens element and a second lens element, the second optical system also including an actuator, the transverse magnification equal to a size of the image of the target divided by a corresponding size of the target when the image of the target is focused onto the photosensitive array; a second electronic system configured to drive the actuator to focus the image of the target onto the photosensitive array and to realize a first value for the transverse magnification by setting a distance between the first and second lens elements in response to a second distance from the laser tracker to the target; and third electronics system that converts the image of the target into a digital data set.