Abstract: A method for determining a distance to a target by a geodetic instrument is disclosed. The method comprises emitting an optical pulse towards a target at an emission time, applying a bias adjustment to a photodiode that is arranged to receive a return optical pulse reflected at the target, obtaining a reference signal that is indicative of a transient behavior of the photodiode for the bias adjustment, obtaining a difference signal by subtracting, from a signal output from the photodiode, a signal that resembles, or is equal to, the transient behavior of the photodiode in response to the bias adjustment based on the reference signal, extracting a reception time that corresponds to reception of the return optical pulse at the photodiode based at least in part on the difference signal, and determining the distance to the target based on the emission time and the reception time.

Abstract: A method for determining a distance to a target by a geodetic instrument is disclosed. The method comprises emitting an optical pulse towards a target at an emission time, applying a bias adjustment to a photodiode that is arranged to receive a return optical pulse reflected at the target, obtaining a reference signal that is indicative of a transient behavior of the photodiode for the bias adjustment, obtaining a difference signal by subtracting, from a signal output from the photodiode, a signal that resembles, or is equal to, the transient behavior of the photodiode in response to the bias adjustment based on the reference signal, extracting a reception time that corresponds to reception of the return optical pulse at the photodiode based at least in part on the difference signal, and determining the distance to the target based on the emission time and the reception time.