Optical surveying instrument

Optical surveying instrument, comprising:

• an optical arrangement defining a field of view and a viewing axis;
• a first image sensor configured to obtain, using light in a first wavelength range, a first image of the field of view;
• a light emitter configured to emit light in a second wavelength range towards the field of view;
• a second image sensor configured to obtain, using light in the second wavelength range, a second image of the field of view;
• a first image processing unit configured to identify a target position of a reflecting target in the first image by detecting a known image pattern of the reflecting target in the first image, wherein the reflecting target includes a rotational body, and detecting the known image pattern in the first image includes processing the first image using a neural network to identify the rotational body;
• and
• a second image processing unit configured to:
• define a region of interest in the second image based on the identified target position in the first image;
• and
• detect a reflector position of a reflector of the reflecting target in the region of interest;
• a tracking unit configured to:
• determine a positional deviation of the reflecting target in the second image relative to the viewing axis, wherein the viewing axis passes through a defined position of the second image;
• and
• orient the viewing axis towards the reflecting target by executing a rotation of the optical arrangement to compensate for the positional deviation.