Laser tracker having target-seeking functionality

Laser tracker for continuously tracking a reflective target and for determining the position of the target with

• a base defining a vertical axis,
• a beam deflecting unit for emitting a measurement radiation and for receiving at least a part of the measurement radiation reflected by the target as reflected illumination radiation bundle, with
• the beam deflecting unit pivoting around the vertical axis and a tilt axis relative to the base in a motorized manner and
• a measurement axis being defined by the emission direction of the measurement radiation,
• a position-sensitive fine targeting detector defining a fine targeting field of view for fine targeting and tracking the target by detecting the measurement radiation reflected by the target,
• a fine distance measurement unit for precisely determining the distance to the target with the help of the measurement radiation, and
• an angle measuring functionality for determining an orientation of the beam deflecting unit relative to the base, wherein:
• a target-seeking unit with
• at least a first illumination light for illuminating the target with electromagnetic illumination radiation,
• at least a first and a second optical mapping unit each defining a field of view, wherein
• the optical units can be used to acquire a picture,
• the optical mapping units are characterized by a fix distance to one another, defining a first basic length, and
• the optical mapping units are positioned so close to the first illumination light, that both optical mapping units are within the cross-section of the illumination radiation bundle reflected by the target,
• at least one position-sensitive detector,
• an optical axis, with the optical axis being offset regarding the measurement axis, and
• a control and evaluating unit with seeking functionality for finding the target depending on a first and a second light spot so that the measurement radiation can be directed towards the target based on finding the target,
• with, when executing the seeking functionality,
• one part of illumination radiation of the first illumination light reflected by the target being acquired by the first optical mapping unit as a first light spot and by the second optical mapping unit as a second light spot in the picture,
• at least one picture position being determined depending on the first and/or second light spot on the detector,
• a parallax correction information being determined by picture processing the picture taken, where a separation of the light spots is taken into account and that depends on a distance of the two light spots to one another, and
• the process of finding the target being performed using the at least one picture position and depending on the parallax correction information, so that a parallax defined by the measurement axis and the optical axis of the target-seeking unit is taken into account.

A laser tracker for continuously tracking a reflective target and for determining the position of the target with

• a base defining a vertical axis,
• a beam deflecting unit for emitting a measurement radiation and for receiving at least a part of the measurement radiation reflected by the target, with
• the beam deflecting unit pivoting around the vertical axis and a tilt axis relative to the base in a motorized manner and
• a measurement axis being defined by an emission direction of the measurement radiation,
• a position-sensitive fine targeting detector defining a fine targeting field of view for fine targeting and tracking the target by detecting the measurement radiation reflected by the target,
• a fine distance measurement unit for precise distance determination to the target with the help of the measurement radiation,
• an angle measurement functionality for determining an orientation of the beam deflecting unit relative to the base, and
• a target-seeking unit with
• an illumination light for illuminating the target with electromagnetic illumination radiation,
• a camera defining a field of view with a position-sensitive detector, with
• the camera, regarding its optical axis, being offset to the measurement axis,
• the camera being used in order to acquire a picture,
• the picture being used in order to determine a picture position X using the illumination radiation reflected by the target, and
• a control and evaluating unit including a seeking functionality for finding the target, configured in such a way that, when executing the seeking functionality, the process of finding the target depends on the picture position so that the measurement radiation can be directed towards the target on the basis of finding the target, wherein:
• the target-seeking unit is equipped with an omnidirectional means for target distance determination for sending and receiving a measurement signal that can be used to determine a roughly approximated distance to the target by capturing a time of flight, phase information, and/or strength of the measurement signal, when executing the seeking functionality, and
• the process of finding the target is performed depending on the picture position X using the determined roughly approximated distance so that a parallax defined by the measurement axis and the optical axis of the camera is taken into account.