Correction for errors in optical pulsed range measurements.

Corrections for the errors that occur in pulsed optical ranging such as satellite ranging are generally analyzed. It is shown that corrections for range errors can be described as a linear combination of the atmospheric correction, the spatial correction, and the corrections for the errors in electrical circuits. A method for the calibration and the correction of observed distances by using a standard target is presented. Particularly in local ranging, corrected distances are easily calculated by two standard targets, even if the atmospheric refractive index and the accuracy of the time base of the counter are unknown. Ranging experiments on earth from 100 m to 10 km were made with the laser system. The corrected distances, using two standard targets, agree well with distances measured accurately by a Geodimeter within the pulse width of the laser, 50 nsec (7.5 m), and the resolution of the time interval counter, 10 nsec (1.5 m).