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Next: Calibrating the Latitudinal Angle. Up: Calibration. Previous: Calibration.

Calibrating the Range.

The rangefinder is well calibrated by the manufacturer to return accurate measurements over a wide range of values (0 to 15m). Still, there are a few steps a user can take to improve the range values read. First, the rangefinder can return a more confident value if it has a longer period to make a measurement. Knowing this, we typically set the collection rate to 1/2 to 1/3 of the peak rate, and have seen dramatic improvements in the data.

The second is limiting the maximum range value that the rangefinder will return. The rangefinder modulates the laser light to create an interference pattern, so to avoid harmonics, it must look at the longest possible distances first. If this distance is set to be shorter than the maximum, the device can settle on a modulation frequency more quickly, returning a better indication of the range.

Lars S. Nyland