Automatic aiming (ATR)
Description
Automatic aiming is the function which recognises and measures the position of a prism using a CCD array. A laser beam is transmitted and the reflected beam is received by the built-in CCD array. The position of the reflected spot with respect to the centre of the CCD is computed. These automatic aiming offsets are used to correct the horizontal and vertical angles. The automatic aiming offsets are also used to control the motors which turn the instrument to centre the crosshairs to the prism. In order to minimise the time for measuring, the crosshairs are not moved to the exact centre of the prism. The automatic aiming offset can be up to 500 cc depending on selected Measure mode. The automatic aiming function measures the offsets between the crosshairs and prism centre and corrects the horizontal and vertical angles accordingly. Therefore the horizontal and vertical angles are measured to the prism-centre, even if the crosshairs are not aimed precisely at the centre of the prism. Motorised instruments can be equipped with automatic aiming.
For Target aiming: Automatic the instrument can find a static prism and measure a distance once Meas or Dist is pressed. The instrument does not follow a moving prism. The crosshairs of the telescope may not fully coincide with the centre of the prism when viewed through the telescope. The remaining automatic aiming offsets for the horizontal and vertical angles are measured by the automatic aiming function and applied to the measured and displayed angles.
